• 제목/요약/키워드: Model-drug distribution

검색결과 79건 처리시간 0.024초

Radiosensitivity Enhancement by Arsenic Trioxide in Conjunction with Hyperthermia in the EC-1 Esophageal Carcinoma Cell Line

  • Cui, Yan-Hui;Liang, Hai-Jun;Zhang, Qing-Qin;Li, Si-Qing;Li, Xiao-Rui;Huo, Xiao-Qing;Yang, Qing-Hui;Li, Wei-Wei;Gu, Jian-Fa;Hua, Qin-Liang;Lu, Ping;Miao, Zhan-Hui
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권4호
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    • pp.1693-1697
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    • 2012
  • Objective: To explore the effect on radiosensitivity of arsenic trioxide ($As_20_3$) in conjunction with hyperthermia on the esophageal carcinoma EC-1 cell line. Method: Inhibition of EC-1 cell proliferation at different concentrations of $As_20_3$ was assessed using the methyl thiazolyl blue colorimetric method (MTT method), with calculation of $IC_{50}$ value and choice of 20% of the $IC_{50}$ as the experimental drug concentration. Blank control, $As_20_3$, hyperthermia, radiotherapy group, $As_20_3$ + hyperthermia, $As_20_3$ + radiotherapy, hyperthermia + radiotherapy and $As_20_3$ + hyperthermia + radiotherapy groups were established, and the cell survival fraction (SF) was calculated from flat panel colony forming analysis, and fitted by the 'multitarget click mathematical model'. Flow cytometry (FCM) was used to detect changes in cell apoptosis and the cell cycle. Results: $As_20_3$ exerted inhibitory effects on proliferation of esophageal carcinoma EC-1 cells, with an $IC_{50}$ of 18.7 ${\mu}mol/L$. After joint therapy of $As_20_3$ + hyperthermia + radiotherapy, the results of FCM showed that cells could be arrested in the $G_2$/M phase, and as the ratio of cells in $G_0/G_1$ and S phases decreased, cell death became more pronounced. Conclusion: $As_20_3$ and hyperthermia exert radiosensitivity effects on esophageal carcinoma EC-1 cells, with synergy in combination. Mechanistically, $As_20_3$ and hyperthermia mainly influence the cell cycle distribution of EC-1 esophageal carcinoma cells, decreasing the repair of sublethal damage and inducing apoptosis, thereby enhancing the killing effects of radioactive rays.

MIA로 골관절염 유발된 동물모델에서 산수유(山茱萸) 30% Ethanol 추출물의 개선 효과 (Improvement Effect of Corni Fructus 30% Ethanol Extract by MIA-Induced Osteoarthritis Animal Model)

  • 김민주;이진아;신미래;박해진;노성수
    • 대한본초학회지
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    • 제35권1호
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    • pp.35-44
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    • 2020
  • Objectives : The objective of this study was to investigate the therapeutic effect of Corni Fructus 30% ethanol extract (CFE) on the monosodium iodoacetate (MIA)-induced osteoarthritis rats. Methods : The subjects were divided into 4 groups ; Normal group (N, n=10), MIA-induced osteoarthritis control group (Con, n=10), indomethacin 5 mg/kg treated group (INDO, n=10), CFE 200 mg/kg treated group (CFE, n=10). Blood and articulation tissues were collected after two weeks of drug administration. Oxidative stress was analyzed with reactive oxygen species (ROS), peroxynitrite (ONOO-). And the Nuclear factor erythroid-2 (Nrf2), heme oxygenase-1 (HO-1), superoxide dismutase (SOD), catalase, glutathione peroxidase-1/2 (GPx-1/2), Nuclear Factor Kappa B p65 (NF-κBp65), cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), tumor necrosis factor-alpha (TNFα), interleukin-6 (IL-6), Interleukin 1β (IL-1β), matrix metalloproteinase-1 (MMP-1), and tissue inhibitor of metalloproteinases-1 (TIMP-1) were investigated by western blot. Results : The administration of CFE showed a significant reduction of changes in relative hind paw weight distribution. Reactive oxygen species (ROS) and peroxy nitrite (ONOO-) levels of articulation tissues were significantly decreased in CFE compared to the control group. Western blot measurements of Nrf2, HO-1, SOD, catalase, GPx-1/2 showed that the CFE group was increased compared to the Con group. And western blot measurements of NF-κBp65, COX-2, iNOS, TNFα, IL-6, IL-1β showed that the CFE group was reduced compared to the Con group. Also CFE group decreased MMP-1 and increased TIMP-1. Conclusion : Based on the above results, it can be seen that osteoarthritis is improved when Corni Fructus 30% ethanol extract treated.

측두하악관절에서의 골관절염 유도 동물모델 비교연구 (A Comparison Study on Animal Models for Osteoarthritis in Temporomandibular Joint)

  • 유선녕;이영철;박혜련;유미현;전혜미;김광연;김상헌;옥수민;고명연;안용우;안순철;정성희
    • Journal of Oral Medicine and Pain
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    • 제36권4호
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    • pp.261-271
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    • 2011
  • 측두하악관절에서 발생하는 골관절염은 저작시 통증, 개구제한, 관절잡음, 교합변화를 유발하여 환자의 삶의 질을 저하시키는데 관여하는 주요한 질환이다. 골관절염의 진행과정과 그에 따른 제어방법을 연구하기 위하여 다양한 연구방법이 시도되고 있다. 이 중 골조직면에서의 조직변화, 활막액의 성분변화, 활막의 조직변화, 주변조직의 변화, 통증에 대한 반응을 확인할 수 있는 동물모델이 주로 많이 이용된다. 본 연구에서는 실험동물에서 다양한 방법으로 측두하악관절 골관절염을 유도하여 하악관절표면에서 일어난 조직변화를 비교 관찰하였으며 각 동물모델의 연구 활용방안에 대하여 탐색하였다. 측두하악관절의 관절강에 monosodium iodoacetate (MIA) 와 interleukin-$1{\alpha}$(IL-$1{\alpha}$)를 직접 주입하여 약물로 관절염을 유도하여 관절조직면을 관찰하였다. 또한 여성호르몬인 에스트로겐에 의한 골변화를 확인하기 위하여 난소절제술로 인한 골다공증 유발모델에서의 하악관절을 관찰하였으며, 노화된 백서의 관절면을 확인함으로써 노화로 인한 골변화를 관찰하였다. Safranin-O 염색 법과 Masson's trichrome 염색법을 이용하여 각각의 관절면에서 세포배열의 변화, 콜라겐의 변화, 골조직의 변화 및 파괴양상에 대하여 확인하였고 Safranin-O의 양성반응을 확인하여 proteoglycans (PGs)의 조직내 분포를 추적하였다.

제조업체 Private Labels 도입의 선행요인 : 전략적 시장관리 관점을 중심으로 (Antecedents of Manufacturer's Private Label Program Engagement : A Focus on Strategic Market Management Perspective)

  • 임채운;이호택
    • 한국유통학회지:유통연구
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    • 제17권1호
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    • pp.65-86
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    • 2012
  • 우리나라에 유통업체상표(Private Label)가 도입된 지 10년이 넘었음에도 불구하고 유통업체 상표에 대한 대부분의 연구는 소비자 관점에서 진행되어져 왔다. 본 연구는 유통업체상표를 소비자 관점이 아닌 제조업체의 관점에서 바라본 연구로, 제조업체의 유통업체상표 생산에 영향을 미치는 내외부적 요인들에 대해서 자원기반이론과 S-C-P Paradigm의 통합적인 연구모형인 전략적 시장관리 관점을 제시하였다. 연구결과를 보면, 제조업체의 마케팅 역량이 높을수록 전체 매출에서 유통업체상표가 차지하는 매출이 적은 것으로 나타났으며, 마케팅 역량에는 제조업체 브랜드명성, 마케팅 투자, 제품포트폴리오 등이 영향을 미치는 것으로 나타났다. 또한 제조업체의 마케팅 역량과 유통업체 상표 생산 간의 관계에는 제조업체의 경쟁강도가 조절효과를 미치는 것으로 나타났는데, 이는 일반적으로 마케팅 역량이 높은(낮은) 기업일수록 전체 매출에서 유통업체상표가 차지하는 비율이 낮지만(높지만), 이러한 기업들 중 경쟁강도를 낮게 지각하는 제조업체의 전체매출 중 유통업체상표가 차지하는 매출은 경쟁강도를 높게 지각하는 제조업체들에 비해 상대적으로 높게 나타났다. 이러한 연구결과를 바탕으로, 본 연구는 유통업체상표 생산에 대한 이론 및 실무적인 시사점을 제시하고 있다.

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집단치료사업에 따른 간흡충증의 역학적 변동에 관한 조사 (Studies on the Epidemiological Change of Clonorchiasis After Mass Chemotherapy in Highly endemic Areas)

  • 주경환;주봉덕;임한종;이준상
    • 농촌의학ㆍ지역보건
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    • 제12권1호
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    • pp.80-93
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    • 1987
  • Mass chemotherapy of Clonorchis sinensis infection in Korea was started in 1982 with 40mg/kg body weight single dose administration scheme of praziquantel. The purpose of this study was to investigate the efficiency of current mass chemotherapy project and compare the epidemiological changes in endemic area of Ckmorchis sinensis. This study was performed at Kimhae-city and Samrangjin-eup of Miryang-gun, Kyongnam province, highly endemic area of C. sinensis located southeastern part of Korea from July to October of 1986. The therapy project of Kimhae area was performed in 1984, whereas that of Samrangjin was done in 1985 by stool examination of the Korea Association for Parasite Eradication(KAPE) and drug administration of local health centre. The results obtained were as follows; 1) As a results of stool examination from 234 specimens obtained in Kimhae area, the infection rate has decreased to 34.2%from 45.6p in 1983, but the infection rate of C. sinensis from 341 specimens obtained in Samrangjin area did not decrease (58.1%in 1986 490%in 1983). 2) The study in Kimhae area showed that the average EPG decreased remarkably from 4,858 to 1,340 and those classified above the category of heavy infection decreased also from 14.0pp to 1.7%. The study in Samrangjin area showed that the average EPG did decrease drastically from 9,597 to 6,498 and those classified above the category of heavy infection did not go down drastically from 25.2% to 14.2%. 3) The study in Kimhae area showed decrease of Cs.$D._{50}$ in comparison to that in 1983, wheareas Cs.$D._{50}$ in Samrangjin area showed no much difference compared to that in 1983. The intensities of endemicity were represented with the regression equation calculated with the cumulative percentages of EPG count. Regression equation was Y=4.49+1.19 log x in Kimhae area and Y=3.66+127 log x in Samrangjin area. 4) The two stage catalytic model was applied and the calculation lead to the equation $Y=5.33(e^{-0.018t}-e^{-0.016t})$ in Kimhae area and $Y=1.25(e^{-0.010t}-e^{-0.018t})$ in Kimhae area and $Y=125(e^{-0.010t}-e^{-0.050t})$ in Samrangjin area 5) The infection rate of cercaria in P.manchouric-us studied in Kimhae area showed 1.25% which is not much different from that in previous years, wheareas the infection rate of metacercaria in P. parva studied in the same area this year showed 2.5-20.2/gm of flesh in comparison to 64/gm of flesh in 1983. 6) Data of C. sinensis infection on the reservoir host in Kimhae area showed 4 out of 18 dogs, 1 out of 18 rats and that in Samrangjin area showed 2 out of 18 dogs respectively. 7) Among the inhabitants who were under mass chemotherapy in Kimhae area, 71out of them, upon stool examination, showed infection rate of 66.2% and those classified above the category of heavy infection, 2.4%. In comparison to infection rate of 33.7% and those classified above the category of heavy infection, which is 1.0%, obtained from those not under mass chemotherapy showed higher infection rate and somewhat equal distribution of intensity of infection. The above statements reflect the fact that individual therapy besides mass chemotherapy was prevalent in that area. 8) On the other side, the studies in Samrangjin area showed infection rate of 68.7% and those above the category of heavy infection, which is 6.1%, in comparison to infection rate of 58.3% and those above the category of heavy infection, which is 16.5%, in those not under mass chemotherapy. the above reflects that although a good deal of inhabit-ants were classified under light or moderate infection category, those above the category of heavy infection, yet, numbered a lot, and individual chemotherapy has not been going on. In conclusion, it was suggested that the number of reinfected inhabitants among those under mass chemotherapy were numerous. Accordingly, the reinforcement of health education should be followed with mass chemotherapy. The facts of high infection rate exemplified by 65% and high number of those above the category of heavy infection in Samrangjin area say that reevaluation of dosage, number of medication and intervals should be necessarily made.

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병원중심 가정간호사업 관리대상범위 확대를 위한 기초연구 (A Preliminary Study for Expending of Hospital-Based Horne Health Care Coverage - Focused on Accident Inpatients Who has the Workers Compensation Insurance -)

  • 이숙자;이진경;유호신
    • 가정간호학회지
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    • 제6권
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    • pp.5-18
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    • 1999
  • This study was attempt to encourage for developing on rehabilitation delivery system and programs as a substitute service instead of hospitalization for accident patients at work, such as hospital based home health care nursing service. It needs vary substitutes service of hospitalization to curtail the length of stay for inpatients who were hospitalized with workers compensation insurance. It focused on developing an estimation of early discharge day of accident inpatients based on a detail statement of treatment for 115 inpatients who were hospitalized at General Hospital in 1997. This study has four specific purpose as follows. First, to find out the status of health service utilization. Second, to estimate the early discharge days and income increasing effect based on the early discharge for those patients. Third, to identify the factors to affect total medical expenditure and the length of stay for those inpatients. Forth, to figure out the need of utilizing home health care nursing service for accident patients. In order to analyze of the length of stay and medical expenditure for inpatients who were hospitalized due to the accident, the authors conducted with micro-analysis and macroanalysis from medical records and medical expenditure records. Micro-analysis was done by nominal group discussion of 4 expertise with the critical criteria. such as a decrease in the amount of treatment after surgery, treatments, tests, drugs and changes in the tests consistency, drug methods, vital signs, start of ROM exercise, doctor's order, patient's outside visiting ability, stable conditions. In addition to identify affected variables for medical expenditure. the length of stay and income effect due to early discharge day, the data was analyzed with multiple regression analysis and linear regression analysis model by SPSS-PC for windows and Excell program. Results of this study as follows. First, the mean length of stay was 37.1 days, whereas the mean length of stay due to early discharge was 28.2 days at the hospital. The estimation of early discharge days were shown that depends on the length of stay. The longer length of stay, the longer length of early discharge days, such as under 7 days length of stay patients was to estimated the mean length of stay was 4.9 days and early discharge days was 4.6. whereas the mean length of stay was 122.6 days and early discharge days was 92.0 respectively. The mean medical expenditure per day were found to be 133.409 Won. whereas the mean medical expenditure per day was shown negative linear trends according to the length of stay at the hospital. The estimation results of the income effect due to 11 early discharge days per bed was around 2,150,000 won. However, it means not the real benefits from early discharge, but the income increasing amount without considering medical prime cost in general hospital. Therefore, it needs further analysis on the cost containments and benefits under the considering as well turn over rates per bed as the medical prime costs. The length of stay was most significant and the sign was positive to the total medical expenditure, as expected. Surgery and patient's residential area also an important variable in explaining medical expenditure. The level of complications was most significant variable in explaining the length of stay. The level of the needs on horne health care nursing service which can be used for early discharge accident patients were shown very high. The needs distribution varied from 65.5% of patients and 88.9% of caregivers, to 96.4% of doctors, and 99.1% of nurses. In addition horne health nurse responded that they can be managed the accident inpatients from early discharge. From these research findings. the following suggestions has been drawn it needs to develop strategies on rehabilitation delivery system in order to focused on consumer's side which is planned for 21 century health policy in Korea. Vary intermediate facilities and horne health care would have been developed in the community based for comprehensive rehabilitation services as a substitutes of hospitalization for shortening the length of stay of hospitalizations. In hospital based horne health care nursing service, it's available immediately to utilize for the patients who wanted rehabilitation services as a substitutes of hospitalization under the cooperations with workers compensation insurance company.

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고혈압 환자에서 혈장 고분자량 아디포넥틴 농도와 심장-대사위험인자와의 관련성 연구 (Plasma Levels of High Molecular Weight Adiponectin are Associated with Cardiometabolic Risks in Patients with Hypertension)

  • 정혜경;신민정
    • Journal of Nutrition and Health
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    • 제41권8호
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    • pp.733-741
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    • 2008
  • 고혈압 환자 110명을 대상으로 혈장 고분자량 아디포넥틴과 총 아디포넥틴 농도를 측정하고 심장-대사위험인자와의 관련성을 비교 평가한 연구 결과를 요약하면 다음과 같다. 1) 비만군과 비비만군으로 나누어 비교한 결과, 고분자량 아디포넥틴 농도는 비만군에서 유의적으로 낮았으나 총 아디포넥틴 농도는 두군간 유의적인 차이를 보이지 않았다. 2) 비만도를 나타내는 BMI 및 허리둘레의 경우 고분자량 아디포넥틴과 음의 상관관계를 보였으나 혈장 아디포넥틴과는 유의적인 상관관계를 보이지 않았다. 3) 혈액 지질 수준과의 상관성 평가시, 고분자량 아디포넥틴은 중성지방과 음의 상관관계를, 고밀도 콜레스테롤과는 양의 상관관계를 보였으며 혈장 아디포넥틴의 경우 단지고밀도 콜레스테롤과 유의적인 양의 상관관계를 보였다. 4) 인슐린 저항성 지표인 HOMA-IR의 경우 고분자량 아디포넥틴 및 혈장 아디포넥틴 모두와 음의 상관관계를 보였다. 5) 염증지표와의 상관성 분석 시, 고분자량 아디포넥틴은 C-반응성 단백질, IL-6과 강한 음의 상관 관계를 TNF-${\alpha}$, ICAM-1과 음의 경향을 보였으나 혈장 아디포넥틴은 C-반응성 단백질외에는 상관관계를 보이지 않았다. 또한 회귀분석 결과, 혈장 고분자량 아디포넥틴 농도는 C-반응성 단백질 수준을 예측하는 독립적 인자였다. 위의 결과로 보아 고분자량 아디포넥틴은 혈장 아디포넥틴보다 전반적으로 심장-대사위험인자와 더 많은 상관성을 보여주었다. 따라서 심혈관 질환 및 대사성증후군을 예측하고 반영하는 데 혈장 고분자량 아디포넥틴 수준이 총 아디포넥틴 수준보다 민감하고 정확한 지표로 활용될 수 있을 것이다.

Sensory Information Processing

  • Yoshimoto, Chiyoshi
    • 대한의용생체공학회:의공학회지
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    • 제6권2호
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    • pp.1-8
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    • 1985
  • The wall shear stress in the vicinity of end-to end anastomoses under steady flow conditions was measured using a flush-mounted hot-film anemometer(FMHFA) probe. The experimental measurements were in good agreement with numerical results except in flow with low Reynolds numbers. The wall shear stress increased proximal to the anastomosis in flow from the Penrose tubing (simulating an artery) to the PTFE: graft. In flow from the PTFE graft to the Penrose tubing, low wall shear stress was observed distal to the anastomosis. Abnormal distributions of wall shear stress in the vicinity of the anastomosis, resulting from the compliance mismatch between the graft and the host artery, might be an important factor of ANFH formation and the graft failure. The present study suggests a correlation between regions of the low wall shear stress and the development of anastomotic neointimal fibrous hyperplasia(ANPH) in end-to-end anastomoses. 30523 T00401030523 ^x Air pressure decay(APD) rate and ultrafiltration rate(UFR) tests were performed on new and saline rinsed dialyzers as well as those roused in patients several times. C-DAK 4000 (Cordis Dow) and CF IS-11 (Baxter Travenol) reused dialyzers obtained from the dialysis clinic were used in the present study. The new dialyzers exhibited a relatively flat APD, whereas saline rinsed and reused dialyzers showed considerable amount of decay. C-DAH dialyzers had a larger APD(11.70$\pm$1.32mmHg/min)compared to CF dialyzers(4.32$\pm$0.55mmHg/min)(p<0.05). However, there was no observable difference in the UFR between the two dialyzers. Neither APD nor UFR showed any significant increase with an increasing number of reuses for up to more than 20reuses. A substantial number of failures observed in APD(larger than 20mmHe/min)on the reused dialyzers(2 out of 40 CP and S out 26 C-DAK) were attributed to the Possible damage on the fibers. The CF 15-11 HFDs which failed APD test did not show changes in the UFR compared to normal dialyzers indicating that APD is a more sensitive test than UFR test to evaluate the integrity of the fibers. 30527 T00401030527 ^x For quantitative measurement of reflected light from a clinical diagnostic strip, a prototype old reflectance photometer was designed. The strip loader and cassette were made to obtain more accurate reflectance parameters. The strip was illuminated at 45˚c through optical fiber and the intensity of reflected light was determined at rectanguLat angle using a photodiode. The kubelka-munk coefficient and reflection optical density were determined ar four different wavelengths(500, 550, 570 and 610nm) for blood glucose strip. For higher concentration than 300mg/41 about glucose, a saturation state of abforbance was observed at 500, 550 and 570nm. The correlation between glucose concentration and parameters was the best at 610nm. 30535 T00401030535 ^x Radiation-induced fibrosarcoma tumors were grown on the flanks of C3H mice. The mice were divided into two groups. One group was injected with Photofrin II, intravenously (2.5mg/kg body weight). The other group received no Photofrin II. Mice from both groups were irradialed for approximately 15 minutes at 100, 300, or 500 mW/cm2 with the argon (488nm/514.5 nm), dye(628nm) and gold vapor (pulsed 628 nm) laser light. A photosensitizer behaved as an added absorber. Under our experimental conditions, the presence of Photolfrin II increased surface temperature by at least 40% and the temperature rise due to 300 mW/cm2 irradiation exceeded values for hyperthermia. Light and temperature distributions with depth were estimated by a computer model. The model demonstrated the influence of wavelength on the thermal process and proved to be a valuable tool to investigate internal temperature rise. 30536 T00401030536 ^x We investigated the structural geometry of thirty-eight Korean femurs. The purpose of this study is to identify major geometrical differences between Korean femurs 3nd others that we believe belong to Caucasians so that we would be able to get insights into the femoral component design that fits Asians including Koreans. We utilized computerized tomography (CT) images of femurs extracted from cadavers. The CT images were transformed into bitmap data by using a film scanner, and then analyzed by using a commercially available software called Image v.1.0 and a Macintosh IIci computer.The resulting data were compared with already published data. The major results show that the geometry of the Korean femurs is significantly different from that of Caucasians: (1) the anteversion angle and the canal flare index are greater by the amount of approximately 8˚ and 0.5, respectively, (2) the shape of the isthmus cross section is more round, and (3) the distance between the teaser trochanter and the proximal border of the isthmus is shelter by about 15 mm. The results suggested that the femoral component suitable for Asians should be different from the currently-used components designed and manufactured mostly by European or American companies. 30537 T00401030537 ^x It is well known that nonlinear propagation characteristics of the wave in the tissue may give very useful information for the medical diagnoisis. In this paper, a new method to detect nonlinear propagation characteristics of the internal vibration in the tissue for the low frequency mechanical vibration by using bispectral analysis is proposed. In the method, low frequency vibration of f0( = 100Hz) is applied on the surface of the object, and the waveform of the internal vibration x (t) is measured from Doppler frequency modulation of silmultaneously transmitted probing ultrasonic waves. Then, the bispectra of the signal x (t) at the frequencies (f0, f0) and (f0, 2f0) are calculated to estimate the nonlinear propagation characteristics as their magnitude ratio, w here since bispectrum is free from the gaussian additive noise we can get the value with high S/N. Basic experimental system is constructed by using 3.0 MHz probing ultrasonic waves and the several experiments are carried out for some phantoms. Results show the superiority of the proposed method to the conventional method using power spectrum and also its usefulness for the tissue characterization. 30541 T00401030541 ^x This paper describes the implementation of a computerized radial pulse diagnosis by aids of a clinical expert. On this base, we composed of the radial pulse diagnosis system in korean traditional medicine. The system composed of a radial pulse wave detection system and a radial pulse diagnosis system. With a detection system, we detected Inyoung and Cheongu radial pulse wave and processed it. Then, we have got the characteristic parameters of radial pulse wave and also quantified that according to the method of Inyoung-Cheongu Comparison Radial Pulse Diagnosis. We defined the jugement standard of radial pulse diagnosis system and then we confirmed the possibility for realization of automatic radial pulse diagnosis in korean traditional medicine. 30545 T00401030545 ^x Microspheres are expected to be applied to biomedical areas such as solid-phase immunoassays, drug delivery systems, immunomagnetic cell separation. To synthesize microspheres for biomedical application, "two stage shot growth method" was developed. The uniformity ratio of synthesized microspheres was always smaller than 1.05. And the surface charge density (or the number of ionizable functional groups) of the microspheres synthesized by "two stage shot growth method" was 6~13 times higher than that of the microspheres synthesized by conventional seeded batch copolymerization. As a previous step for biomedical application, adsorption experiments of bovine albumin on microspheres were carried out under various conditions. The maximum adsorbed amount was obtained in the neighborhood of pH 4.5. Isoelectric point of bovine albumin is pH 5.0, so experimental result shows that it shifted to acid area. The adsorption isotherm was obtained, the plateau region was always reached at 2.Og/L (bulk concentration of bovine albumin).The effect of the kind and the amount of surface functional group was also examined. 30575 T00401030575 ^x A medical image workstation was developed using multimedia technique. The system based on PC-486DX was designed to acquire medical images produced by medical imaging instruments and related audio information, that is, doctors' reporting results. Input information was processed and analyzed, then the results were presented in the form of graph and animation. All the informations of the system were hierarchically related with the image as the apex. Processing and analysis algorithms were implemented so that the diagnostic accuracy could be improved. The diagnosed information can be transferred for patient diagnosis through LAN(local area network). 30592 T00401030592 ^x In the conventional infrared imaging system, complex infrared lens systems are usually used for directing collimated narrow infrared beams into the high speed 2-dimensional optic scanner. In this paper, a simple reflective infrared optic system with a 2-dimensional optic scanner is proposed for the realization of medical infrared thermography system. It has been experimentally proven that the intfrared thermography system composed of the proposed optic system has the temperature resolution of 0.1˚c under the spatial resolution of lmrad, the image matrix size of 256 X 240, and tile imaging time of 4 seconds. 30593 T00401030593 ^x In this paper, MIIS (Medical Image Information System) has been designed and implemented using INGRES RDBMS, which is based on a client/server architecture. The implemented system allows users to register and retrieve patient information, medical images and diagnostic reports. It also provides the function to display these information on workstation windows simultaneously by using the designed menu-driven graphic user interface. The medical image compression/decompression techniques are implemented and integrated into the medical image database system for the efficient data storage and the fast access through the network. 30594 T00401030594 ^x In this paper, computerized BEAM was implemented for the space domain analysis of EEG. Trans-formation from temporal summation to two-dimensional mappings is formed by 4 nearest point inter-polaton method. Methods of representation of BEAM are two. One is dot density method which classify brain electrical potential 9 levels by dot density of gray levels and the other is colour method which classify brain electrical 12 levels by red-green colours. In this BEAM, instantaneous change and average energy distribution over any arbitrary time interval of brain electrical activity could be observed and analyzed easily. In the frequency domain, the distribution of energy spectrum of a special band can easily be distinguished normality and abnormality. 30608 T00401030608 ^x Laboratory information system (LIS) is a key tool to manage laboratory data in clinical pathology. Our department has developed an information system for routine hematology using down-sized computer system. We have used an IBM 486 compatible PC with 16MB main memory, 210 MB hard disk drive, 9 RS-232C port and 24 pin dot printer. The operating system and database management system were SCO UNIX and SCO foxbase, respectively. For program development, we used Xbase language provided by SCO foxbase. The C language was used for interface purpose. To make the system use friendly, pull-down menu was used. The system connected to our hospital information system via application program interface (API), so the information related to patient and request details is automatically transmitted to our computer. Our system interfaced with fwd complete blood count analyzers(Sysmex NE-8000 and Coulter STKS) for unidirectional data tansmission from analyzer to computer. The authors suggests that this system based on down-sized computer could provide a progressive approach to total LIS based on local area network, and the implemented system could serve as a model for other hospital's LIS for routine hematology. 30609 T00401030609 ^x To develop an artificial bone substitute that is gradually degraded and replaced by the regenerated natural bone, the authors designed a composite that is consisted of calcium phosphate and collagen. To use as the structural matrix of the composite, collagen was purified from human umbilical cord. The obtained collagen was treated by pepsin to remove telopeptides, and finally, the immune-free atelocollagen was produced: The cross linked atelocollagen was highly resistant to the collagenase induced collagenolysis. The cross linked collagen demonstrated an improved tensile strength. 30618 T00401030618 ^x This paper is a study on the design of adptive filter for QRS complex detection. We propose a simple adaptive algorithm to increase capability of noise cancelation in QRS complex detection with two stage adaptive filter. At the first stage, background noise is removed and at the next stage, only spectrum of QRS complex components is passed. Two adaptive filters can afford to keep track of the changes of both noise and QRS complex. Each adaptive filter consists of prediction error filter and FIR filter The impulse response of FIR filter uses coefficients of prediction error filter. The detection rates for 105 and 108 of MIT/BIH data base were 99.3% and 97.4% respectively. 30619 T00401030619 ^x To develop an artificial bone substitute that is gradually degraded and replaced by the regenerated natural bone, the authors designed and produced a composite that is consisted of calcium phosphate and collagen. Human umbilical cord origin pepsin treated type I atelocollagen was used as the structural matrix, by which sintered or non-sintered carbonate apatite was encapsulated to form an inorganic-organic composite. With cross linking atelocollagen by UV ray irradiation, the resistance to both compressive and tensile strength was increased. Collagen degradation by the collagenase induced collagenolysis was also decreased. 30620 T00401030620 ^x We have developed a monoleaflet polymer valve as an inexpensive and viable alternative, especially for short-term use in the ventricular assist device or total artificial heart. The frame and leaflet of the polymer valve were made from polyurethane, To evaluate the hemodynamic performance of the polymer valve a comparative study of flow dynamics past a polymer valve and a St. Jude Medical prosthetic valve under physiological pulsatile flow conditions in vitro was made. Comparisons between the valves were made on the transvalvular pressure drop, regurgitation volume and maximum valve opening area. The polymer valve showed smaller regurgitation volume and transvalvular pressure drop compared to the mechanical valve at higher heart rate. The results showed that the functional characteristics of the polymer valve compared favorably with those of the mechanical valve at higher heart rate. 30621 T00401030621 ^x Explosive evaporative removal process of biological tissue by absorption of a CW laser has been simulated by using gelatin and a multimode Nd:YAG laser. Because the point of maximun temperature of laser-irradiated gelatin exists below the surface due to surface cooling, evaporation at the boiling temperature is made explosively from below the surface. The important parameters of this process are the conduction loss to laser power absorption (defined as the conduction-to-laser power parameter, Nk), the convection heat transfer at the surface to conduction loss (defined as Bi), dimensionless extinction coefficient (defined as Br.), and dimensionless irradiation time (defined as Fo). Dependence of Fo on Nk and Bi has been observed by experiment, and the results have been compared with the numerical results obtained by solving a 2-dimensional conduction equation. Fo and explosion depth (from the surface to the point of maximun temperature) are increased when Nk and Bi are increased.To find out the minimum laser power for explosive evaporative removal process, steady state analysis has been also made. The limit of Nk to induce evaporative removal, which is proportional to the inverse of the laser power, has been obtained. 30622 T00401030622 ^x N1 and N2 gross neural action potentials were measured from the round window of the guinea pig cochlea at the onset of the acoustic stimuli. N1-N2 audiograms were made by means of regulating stimulant intensities in order to produce constant N1-N2 potentials as criteria for different input tone pip frequencies. The lowest threshold was measured with an input tone pip I5 dB SPL in intensity and 12 KHz in frequency when the animal was in normal physiological condition. The procedure of experimental measurements is explained in detail. This experimental approach is very useful for the investigation of the Cochlear function. Both noN1inear and active functions of the Cochlea can be monitored by N1-N2 audiograms. 30623 T00401030623 ^x In electrical impedance tomography(EIT), we use boundary current and voltage measurements toprovide the information about the cross-sectional distribution of electrical impedance or resistivity. One of the major problems in EIT has been the inaccessibility of internal voltage or current data in finding the internal impedance values. We propose a new image reconstruction method using internal current density data measured by NMR. We obtained a two-dimensional current density distribution within a phantom by processing the real and imaginary MR images from a 4.77 NMR machine. We implemented a resistivity mage reconstruction algorithm using the finite element method and sensitivity matrix. We presented computer simulation results of the mage reconstruction algorithm and furture direction of the research. 30624 T00401030624 ^x A new method of digital image analysis technique for discrimination of cancer cell was presented in this paper. The object image was the Thyroid eland cells image that was diagnosed as normal and abnormal (two types of abnormal: follicular neoplastic cell, and papillary neoplastic cell), respectively. By using the proposed region segmentation algorithm, the cells were segmented into nucleus. The 16 feature parameters were used to calculate the features of each nucleus. A9 a consequence of using dominant feature parameters method proposed in this paper, discrimination rate of 91.11% was obtained for Thyroid Gland cells. 30625 T00401030625 ^x An electrical stimulator was designed to induce locomotion for paraplegic patients caused by central nervous system injury. Optimal stimulus parameters, which can minimize muscle fatigue and can achieve effective muscle contraction were determined in slow and fast muscles in Sprague-Dawley rats. Stimulus patterns of our stimulator were designed to simulate electromyographic activity monitored during locomotion of normal subjects. Muscle types of the lower extremity were classified according to their mechanical property of contraction, which are slow muscle (msoleus m.) and fast muscle (medial gastrocneminus m., rectus femoris m., vastus lateralis m.). Optimal parameters of electrical stimulation for slow muscles were 20 Hz, 0.2 ms square pulse. For fast muscle, 40 Hz, 0.3 ms square pulse was optimal to produce repeated contraction. Higher stimulus intensity was required when synergistic muscles were stimulated simultaneously than when they were stimulated individually. Electrical stimulation for each muscle was designed to generate bipedal locomotion, so that individual muscles alternate contraction and relaxation to simulate stance and swing phases. Portable electrical stimulator with 16 channels built in microprocessor was constructed and applied to paraplegic patients due to lumbar cord injury. The electrical stimulator restored partially gait function in paraplegic patients. 30626 T00401030626 ^x Two-Dimensional modelling of the Cochlear biomechanics is presented in this paper. The Laplace partial differential equation which represents the fluid mechanics of the Cochlea has been transformed into two-dimensional electrical transmission line. The procedure of this transformation is explained in detail. The comparison between one and two dimensional models is also presented. This electrical modelling of the basilar membrane (BM) is clearly useful for the next approach to the further. Development of active elements which are essential in the producing of the sharp tuning of the BM. This paper shows that two-dimension model is qualitatively better than one-dimensional model both in amplitude and phase responses of the BM displacement. The present model is only for frequency response. However because the model is electrical, the two-dimensional transmission line model can be extended to time response without any difficult. 30627 T00401030627 ^x A method has been proposed for the fully automatic detection of left ventricular endocardial boundary in 2D short axis echocardiogram using geometric model. The procedure has the following three distinct stages. First, the initial center is estimated by the initial center estimation algorithm which is applied to decimated image. Second, the center estimation algorithm is applied to original image and then best-fit elliptic model estimation is processed. Third, best-fit boundary is detected by the cost function which is based on the best-fit elliptic model. The proposed method shows effective result without manual intervention by a human operator. 30628 T00401030628 ^x The intelligent trajectory control method that controls moving direction and average velocity for a prosthetic arm is proposed by pattern recognition and force estimations using EMG signals. Also, we propose the real time trajectory planning method which generates continuous accelleration paths using 3 stage linear filters to minimize the impact to human body induced by arm motions and to reduce the muscle fatigue. We use combination of MLP and fuzzy filter for pattern recognition to estimate the direction of a muscle and Hogan's method for the force estimation. EMG signals are acquired by using a amputation simulator and 2 dimensional joystick motion. The simulation results of proposed prosthetic arm control system using the EMf signals show that the arm is effectively followed the desired trajectory depended on estimated force and direction of muscle movements. 30638 T00401030638 ^x A new neural network architecture for the recognition of patterns from images is proposed, which is partially based on the results of physiological studies. The proposed network is composed of multi-layers and the nerve cells in each layer are connected by spatial filters which approximate receptive fields in optic nerve fields. In the proposed method, patterns recognition for complicated images is carried out using global features as well as local features such as lines and end-points. A new generating method of matched filers representing global features is proposed in this network. 30659 T00401030659 ^x An implementation scheme of the magnetic nerve stimulator using a switching mode power supply is proposed. By using a switching mode power supply rather than a conventional linear power supply for charging high voltage capacitors, the weight and size of the magnetic nerve stimulator can be considerably reduced. Maximum output voltage of the developed magnetic nerve stimulator using the switching mode power supply is 3, 000 volts and switching time is about 100 msec. Experimental results or human nerve stimulations using the developed stimulator are presented. 30768 T00401030768 ^x In this paper, we describe the design methodology and specifications of the developed module-based bedside monitors for patient monitoring. The bedside monitor consists of a main unit and module cases with various parameter modules. The main unit includes a 12.1" TFT color LCD, a main CPU board, and peripherals such as a module controller, Ethernet LAN card, video card, rotate/push button controller, etc. The main unit can connect at maximum three module cases each of which can accommodate up to 7 parameter modules. They include the modules for electrocardiograph, respiration, invasive blood pressure, noninvasive blood pressure, temperature, and SpO2 with Plethysmograph.SpO2 with Plethysmograph.

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High Resolution HC$_3$N Observations toward the Central Region of Sagittarius B2

  • H.S-Ching;Oh, M.ishi;M.Morimoto
    • 한국우주과학회:학술대회논문집(한국우주과학회보)
    • /
    • 한국우주과학회 1993년도 한국우주과학회보 제2권2호
    • /
    • pp.17-17
    • /
    • 1993
  • The wall shear stress in the vicinity of end-to end anastomoses under steady flow conditions was measured using a flush-mounted hot-film anemometer(FMHFA) probe. The experimental measurements were in good agreement with numerical results except in flow with low Reynolds numbers. The wall shear stress increased proximal to the anastomosis in flow from the Penrose tubing (simulating an artery) to the PTFE: graft. In flow from the PTFE graft to the Penrose tubing, low wall shear stress was observed distal to the anastomosis. Abnormal distributions of wall shear stress in the vicinity of the anastomosis, resulting from the compliance mismatch between the graft and the host artery, might be an important factor of ANFH formation and the graft failure. The present study suggests a correlation between regions of the low wall shear stress and the development of anastomotic neointimal fibrous hyperplasia(ANPH) in end-to-end anastomoses. 30523 T00401030523 ^x Air pressure decay(APD) rate and ultrafiltration rate(UFR) tests were performed on new and saline rinsed dialyzers as well as those roused in patients several times. C-DAK 4000 (Cordis Dow) and CF IS-11 (Baxter Travenol) reused dialyzers obtained from the dialysis clinic were used in the present study. The new dialyzers exhibited a relatively flat APD, whereas saline rinsed and reused dialyzers showed considerable amount of decay. C-DAH dialyzers had a larger APD(11.70${\pm}$1.32mmHg/min)compared to CF dialyzers(4.32${\pm}$0.55mmHg/min)(p<0.05). However, there was no observable difference in the UFR between the two dialyzers. Neither APD nor UFR showed any significant increase with an increasing number of reuses for up to more than 20reuses. A substantial number of failures observed in APD(larger than 20mmHe/min)on the reused dialyzers(2 out of 40 CP and S out 26 C-DAK) were attributed to the Possible damage on the fibers. The CF 15-11 HFDs which failed APD test did not show changes in the UFR compared to normal dialyzers indicating that APD is a more sensitive test than UFR test to evaluate the integrity of the fibers. 30527 T00401030527 ^x For quantitative measurement of reflected light from a clinical diagnostic strip, a prototype old reflectance photometer was designed. The strip loader and cassette were made to obtain more accurate reflectance parameters. The strip was illuminated at 45˚c through optical fiber and the intensity of reflected light was determined at rectanguLat angle using a photodiode. The kubelka-munk coefficient and reflection optical density were determined ar four different wavelengths(500,550,570 and 610nm) for blood glucose strip. For higher concentration than 300mg/41 about glucose, a saturation state of abforbance was observed at 500,550 and 570nm. The correlation between glucose concentration and parameters was the best at 610nm. 30535 T00401030535 ^x Radiation-induced fibrosarcoma tumors were grown on the flanks of C3H mice. The mice were divided into two groups. One group was injected with Photofrin II, intravenously (2.5mg/kg body weight). The other group received no Photofrin II. Mice from both groups were irradialed for approximately 15 minutes at 100,300, or 500 mW/cm2 with the argon (488nm/514.5 nm), dye(628nm) and gold vapor (pulsed 628 nm) laser light. A photosensitizer behaved as an added absorber. Under our experimental conditions, the presence of Photolfrin II increased surface temperature by at least 40% and the temperature rise due to 300 mW/cm2 irradiation exceeded values for hyperthermia. Light and temperature distributions with depth were estimated by a computer model. The model demonstrated the influence of wavelength on the thermal process and proved to be a valuable tool to investigate internal temperature rise. 30536 T00401030536 ^x We investigated the structural geometry of thirty-eight Korean femurs. The purpose of this study is to identify major geometrical differences between Korean femurs 3nd others that we believe belong to Caucasians so that we would be able to get insights into the femoral component design that fits Asians including Koreans. We utilized computerized tomography (CT) images of femurs extracted from cadavers. The CT images were transformed into bitmap data by using a film scanner, and then analyzed by using a commercially available software called Image v.1.0 and a Macintosh IIci computer.The resulting data were compared with already published data. The major results show that the geometry of the Korean femurs is significantly different from that of Caucasians: (1) the anteversion angle and the canal flare index are greater by the amount of approximately 8˚ and 0.5, respectively, (2) the shape of the isthmus cross section is more round, and (3) the distance between the teaser trochanter and the proximal border of the isthmus is shelter by about 15 mm. The results suggested that the femoral component suitable for Asians should be different from the currently-used components designed and manufactured mostly by European or American companies. 30537 T00401030537 ^x It is well known that nonlinear propagation characteristics of the wave in the tissue may give very useful information for the medical diagnoisis. In this paper, a new method to detect nonlinear propagation characteristics of the internal vibration in the tissue for the low frequency mechanical vibration by using bispectral analysis is proposed. In the method, low frequency vibration of f0( = 100Hz) is applied on the surface of the object, and the waveform of the internal vibration x (t) is measured from Doppler frequency modulation of silmultaneously transmitted probing ultrasonic waves. Then, the bispectra of the signal x (t) at the frequencies (f0, f0) and (f0, 2f0) are calculated to estimate the nonlinear propagation characteristics as their magnitude ratio, w here since bispectrum is free from the gaussian additive noise we can get the value with high S/N. Basic experimental system is constructed by using 3.0 MHz probing ultrasonic waves and the several experiments are carried out for some phantoms. Results show the superiority of the proposed method to the conventional method using power spectrum and also its usefulness for the tissue characterization. 30541 T00401030541 ^x This paper describes the implementation of a computerized radial pulse diagnosis by aids of a clinical expert. On this base, we composed of the radial pulse diagnosis system in korean traditional medicine. The system composed of a radial pulse wave detection system and a radial pulse diagnosis system. With a detection system, we detected Inyoung and Cheongu radial pulse wave and processed it. Then, we have got the characteristic parameters of radial pulse wave and also quantified that according to the method of Inyoung-Cheongu Comparison Radial Pulse Diagnosis. We defined the jugement standard of radial pulse diagnosis system and then we confirmed the possibility for realization of automatic radial pulse diagnosis in korean traditional medicine. 30545 T00401030545 ^x Microspheres are expected to be applied to biomedical areas such as solid-phase immunoassays, drug delivery systems, immunomagnetic cell separation. To synthesize microspheres for biomedical application, "two stage shot growth method" was developed. The uniformity ratio of synthesized microspheres was always smaller than 1.05. And the surface charge density (or the number of ionizable functional groups) of the microspheres synthesized by "two stage shot growth method" was 6~13 times higher than that of the microspheres synthesized by conventional seeded batch copolymerization. As a previous step for biomedical application, adsorption experiments of bovine albumin on microspheres were carried out under various conditions. The maximum adsorbed amount was obtained in the neighborhood of pH 4.5. Isoelectric point of bovine albumin is pH 5.0, so experimental result shows that it shifted to acid area. The adsorption isotherm was obtained, the plateau region was always reached at 2.Og/L (bulk concentration of bovine albumin).The effect of the kind and the amount of surface functional group was also examined. 30575 T00401030575 ^x A medical image workstation was developed using multimedia technique. The system based on PC-486DX was designed to acquire medical images produced by medical imaging instruments and related audio information, that is, doctors' reporting results. Input information was processed and analyzed, then the results were presented in the form of graph and animation. All the informations of the system were hierarchically related with the image as the apex. Processing and analysis algorithms were implemented so that the diagnostic accuracy could be improved. The diagnosed information can be transferred for patient diagnosis through LAN(local area network). 30592 T00401030592 ^x In the conventional infrared imaging system, complex infrared lens systems are usually used for directing collimated narrow infrared beams into the high speed 2-dimensional optic scanner. In this paper, a simple reflective infrared optic system with a 2-dimensional optic scanner is proposed for the realization of medical infrared thermography system. It has been experimentally proven that the intfrared thermography system composed of the proposed optic system has the temperature resolution of 0.1˚c under the spatial resolution of lmrad, the image matrix size of 256 X 240, and tile imaging time of 4 seconds. 30593 T00401030593 ^x In this paper, MIIS (Medical Image Information System) has been designed and implemented using INGRES RDBMS, which is based on a client/server architecture. The implemented system allows users to register and retrieve patient information, medical images and diagnostic reports. It also provides the function to display these information on workstation windows simultaneously by using the designed menu-driven graphic user interface. The medical image compression/decompression techniques are implemented and integrated into the medical image database system for the efficient data storage and the fast access through the network. 30594 T00401030594 ^x In this paper, computerized BEAM was implemented for the space domain analysis of EEG. Trans-formation from temporal summation to two-dimensional mappings is formed by 4 nearest point inter-polaton method. Methods of representation of BEAM are two. One is dot density method which classify brain electrical potential 9 levels by dot density of gray levels and the other is colour method which classify brain electrical 12 levels by red-green colours. In this BEAM, instantaneous change and average energy distribution over any arbitrary time interval of brain electrical activity could be observed and analyzed easily. In the frequency domain, the distribution of energy spectrum of a special band can easily be distinguished normality and abnormality. 30608 T00401030608 ^x Laboratory information system (LIS) is a key tool to manage laboratory data in clinical pathology. Our department has developed an information system for routine hematology using down-sized computer system. We have used an IBM 486 compatible PC with 16MB main memory, 210 MB hard disk drive, 9 RS-232C port and 24 pin dot printer. The operating system and database management system were SCO UNIX and SCO foxbase, respectively. For program development, we used Xbase language provided by SCO foxbase. The C language was used for interface purpose. To make the system use friendly, pull-down menu was used. The system connected to our hospital information system via application program interface (API), so the information related to patient and request details is automatically transmitted to our computer. Our system interfaced with fwd complete blood count analyzers(Sysmex NE-8000 and Coulter STKS) for unidirectional data tansmission from analyzer to computer. The authors suggests that this system based on down-sized computer could provide a progressive approach to total LIS based on local area network, and the implemented system could serve as a model for other hospital's LIS for routine hematology. 30609 T00401030609 ^x To develop an artificial bone substitute that is gradually degraded and replaced by the regenerated natural bone, the authors designed a composite that is consisted of calcium phosphate and collagen. To use as the structural matrix of the composite, collagen was purified from human umbilical cord. The obtained collagen was treated by pepsin to remove telopeptides, and finally, the immune-free atelocollagen was produced: The cross linked atelocollagen was highly resistant to the collagenase induced collagenolysis. The cross linked collagen demonstrated an improved tensile strength. 30618 T00401030618 ^x This paper is a study on the design of adptive filter for QRS complex detection. We propose a simple adaptive algorithm to increase capability of noise cancelation in QRS complex detection with two stage adaptive filter. At the first stage, background noise is removed and at the next stage, only spectrum of QRS complex components is passed. Two adaptive filters can afford to keep track of the changes of both noise and QRS complex. Each adaptive filter consists of prediction error filter and FIR filter The impulse response of FIR filter uses coefficients of prediction error filter. The detection rates for 105 and 108 of MIT/BIH data base were 99.3% and 97.4% respectively. 30619 T00401030619 ^x To develop an artificial bone substitute that is gradually degraded and replaced by the regenerated natural bone, the authors designed and produced a composite that is consisted of calcium phosphate and collagen. Human umbilical cord origin pepsin treated type I atelocollagen was used as the structural matrix, by which sintered or non-sintered carbonate apatite was encapsulated to form an inorganic-organic composite. With cross linking atelocollagen by UV ray irradiation, the resistance to both compressive and tensile strength was increased. Collagen degradation by the collagenase induced collagenolysis was also decreased. 30620 T00401030620 ^x We have developed a monoleaflet polymer valve as an inexpensive and viable alternative, especially for short-term use in the ventricular assist device or total artificial heart. The frame and leaflet of the polymer valve were made from polyurethane, To evaluate the hemodynamic performance of the polymer valve a comparative study of flow dynamics past a polymer valve and a St. Jude Medical prosthetic valve under physiological pulsatile flow conditions in vitro was made. Comparisons between the valves were made on the transvalvular pressure drop, regurgitation volume and maximum valve opening area. The polymer valve showed smaller regurgitation volume and transvalvular pressure drop compared to the mechanical valve at higher heart rate. The results showed that the functional characteristics of the polymer valve compared favorably with those of the mechanical valve at higher heart rate. 30621 T00401030621 ^x Explosive evaporative removal process of biological tissue by absorption of a CW laser has been simulated by using gelatin and a multimode Nd:YAG laser. Because the point of maximun temperature of laser-irradiated gelatin exists below the surface due to surface cooling, evaporation at the boiling temperature is made explosively from below the surface. The important parameters of this process are the conduction loss to laser power absorption (defined as the conduction-to-laser power parameter, Nk), the convection heat transfer at the surface to conduction loss (defined as Bi), dimensionless extinction coefficient (defined as Br.), and dimensionless irradiation time (defined as Fo). Dependence of Fo on Nk and Bi has been observed by experiment, and the results have been compared with the numerical results obtained by solving a 2-dimensional conduction equation. Fo and explosion depth (from the surface to the point of maximun temperature) are increased when Nk and Bi are increased.To find out the minimum laser power for explosive evaporative removal process, steady state analysis has been also made. The limit of Nk to induce evaporative removal, which is proportional to the inverse of the laser power, has been obtained. 30622 T00401030622 ^x N1 and N2 gross neural action potentials were measured from the round window of the guinea pig cochlea at the onset of the acoustic stimuli. N1-N2 audiograms were made by means of regulating stimulant intensities in order to produce constant N1-N2 potentials as criteria for different input tone pip frequencies. The lowest threshold was measured with an input tone pip I5 dB SPL in intensity and 12 KHz in frequency when the animal was in normal physiological condition. The procedure of experimental measurements is explained in detail. This experimental approach is very useful for the investigation of the Cochlear function. Both noN1inear and active functions of the Cochlea can be monitored by N1-N2 audiograms. 30623 T00401030623 ^x In electrical impedance tomography(EIT), we use boundary current and voltage measurements toprovide the information about the cross-sectional distribution of electrical impedance or resistivity. One of the major problems in EIT has been the inaccessibility of internal voltage or current data in finding the internal impedance values. We propose a new image reconstruction method using internal current density data measured by NMR. We obtained a two-dimensional current density distribution within a phantom by processing the real and imaginary MR images from a 4.77 NMR machine. We implemented a resistivity mage reconstruction algorithm using the finite element method and sensitivity matrix. We presented computer simulation results of the mage reconstruction algorithm and furture direction of the research. 30624 T00401030624 ^x A new method of digital image analysis technique for discrimination of cancer cell was presented in this paper. The object image was the Thyroid eland cells image that was diagnosed as normal and abnormal (two types of abnormal: follicular neoplastic cell, and papillary neoplastic cell), respectively. By using the proposed region segmentation algorithm, the cells were segmented into nucleus. The 16 feature parameters were used to calculate the features of each nucleus. A9 a consequence of using dominant feature parameters method proposed in this paper, discrimination rate of 91.11% was obtained for Thyroid Gland cells. 30625 T00401030625 ^x An electrical stimulator was designed to induce locomotion for paraplegic patients caused by central nervous system injury. Optimal stimulus parameters, which can minimize muscle fatigue and can achieve effective muscle contraction were determined in slow and fast muscles in Sprague-Dawley rats. Stimulus patterns of our stimulator were designed to simulate electromyographic activity monitored during locomotion of normal subjects. Muscle types of the lower extremity were classified according to their mechanical property of contraction, which are slow muscle (msoleus m.) and fast muscle (medial gastrocneminus m., rectus femoris m., vastus lateralis m.). Optimal parameters of electrical stimulation for slow muscles were 20 Hz, 0.2 ms square pulse. For fast muscle, 40 Hz, 0.3 ms square pulse was optimal to produce repeated contraction. Higher stimulus intensity was required when synergistic muscles were stimulated simultaneously than when they were stimulated individually. Electrical stimulation for each muscle was designed to generate bipedal locomotion, so that individual muscles alternate contraction and relaxation to simulate stance and swing phases. Portable electrical stimulator with 16 channels built in microprocessor was constructed and applied to paraplegic patients due to lumbar cord injury. The electrical stimulator restored partially gait function in paraplegic patients. 30626 T00401030626 ^x Two-Dimensional modelling of the Cochlear biomechanics is presented in this paper. The Laplace partial differential equation which represents the fluid mechanics of the Cochlea has been transformed into two-dimensional electrical transmission line. The procedure of this transformation is explained in detail. The comparison between one and two dimensional models is also presented. This electrical modelling of the basilar membrane (BM) is clearly useful for the next approach to the further. Development of active elements which are essential in the producing of the sharp tuning of the BM. This paper shows that two-dimension model is qualitatively better than one-dimensional model both in amplitude and phase responses of the BM displacement. The present model is only for frequency response. However because the model is electrical, the two-dimensional transmission line model can be extended to time response without any difficult. 30627 T00401030627 ^x A method has been proposed for the fully automatic detection of left ventricular endocardial boundary in 2D short axis echocardiogram using geometric model. The procedure has the following three distinct stages. First, the initial center is estimated by the initial center estimation algorithm which is applied to decimated image. Second, the center estimation algorithm is applied to original image and then best-fit elliptic model estimation is processed. Third, best-fit boundary is detected by the cost function which is based on the best-fit elliptic model. The proposed method shows effective result without manual intervention by a human operator. 30628 T00401030628 ^x The intelligent trajectory control method that controls moving direction and average velocity for a prosthetic arm is proposed by pattern recognition and force estimations using EMG signals. Also, we propose the real time trajectory planning method which generates continuous accelleration paths using 3 stage linear filters to minimize the impact to human body induced by arm motions and to reduce the muscle fatigue. We use combination of MLP and fuzzy filter for pattern recognition to estimate the direction of a muscle and Hogan's method for the force estimation. EMG signals are acquired by using a amputation simulator and 2 dimensional joystick motion. The simulation results of proposed prosthetic arm control system using the EMf signals show that the arm is effectively followed the desired trajectory depended on estimated force and direction of muscle movements. 30638 T00401030638 ^x A new neural network architecture for the recognition of patterns from images is proposed, which is partially based on the results of physiological studies. The proposed network is composed of multi-layers and the nerve cells in each layer are connected by spatial filters which approximate receptive fields in optic nerve fields. In the proposed method, patterns recognition for complicated images is carried out using global features as well as local features such as lines and end-points. A new generating method of matched filers representing global features is proposed in this network. 30659 T00401030659 ^x An implementation scheme of the magnetic nerve stimulator using a switching mode power supply is proposed. By using a switching mode power supply rather than a conventional linear power supply for charging high voltage capacitors, the weight and size of the magnetic nerve stimulator can be considerably reduced. Maximum output voltage of the developed magnetic nerve stimulator using the switching mode power supply is 3,000 volts and switching time is about 100 msec. Experimental results or human nerve stimulations using the developed stimulator are presented. 30768 T00401030768 ^x In this paper, we describe the design methodology and specifications of the developed module-based bedside monitors for patient monitoring. The bedside monitor consists of a main unit and module cases with various parameter modules. The main unit includes a 12.1" TFT color LCD, a main CPU board, and peripherals such as a module controller, Ethernet LAN card, video card, rotate/push button controller, etc. The main unit can connect at maximum three module cases each of which can accommodate up to 7 parameter modules. They include the modules for electrocardiograph, respiration, invasive blood pressure, noninvasive blood pressure, temperature, and SpO2 with Plethysmograph.

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