• 제목/요약/키워드: Co-polymer

검색결과 1,925건 처리시간 0.028초

Ganoderma lucium IY009 유래 단백다당류의 분자량 차이에 따른 면역증강활성 (Immunomodulatory Activities by Difference in Molecular Size of the Proteoglycan Extracted from Ganoderma lucidum IY009)

  • 이준우;백성진;방광웅;김용석;김광수;전억한
    • 한국균학회지
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    • 제29권1호
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    • pp.15-21
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    • 2001
  • 본 연구는 Ganoderma lucidum IY009 유래 단백다당류의 분자량 차이에 따른 면역증강활성을 조사하였다. 이것의 분자량은 12kD와 2,000kD의 분자량 분포를 지닌 단백다당류이며, 이 둘 중 어느 분획이 주 약리활성을 나타내는지 규명하기 위해, ultrafiltration 및 column chromatography를 실시하여 고분자 및 저분자 분획으로 분획화를 실시하여 이들에 대한 약리활성을 조사하였다. 항보체 활성화 정도는 항암 활성이 높았던 GMPG-CH 분획에서 가장 높은 393%의 활성능을 보였으며. 고분자 분획이 저분자 분획보다 높은 항보체 활성을 나타내어 단백다당류의 항보체 활성은 항암 활성과 어떠한 관계가 있는 것으로 추정된다. 대식세포에 미치는 영향을 알아보기 위하여 Raw 264.7 세포에 고분자 및 저분자 분획을 첨가하고 nitric oxide 생성 능을 측정한 결과, ${\beta}$-결합 당의 함량이 높은 고분자 분획이 대식세포에 대한 NO 생성능이 높게 나타나는 것을 알 수 있었으며, 대식세포의 활성화 인자인 $IFN-{\gamma}$의 병용 첨가시에는 $IFN-{\gamma}$ 단독 첨가시 보다 약 $5{\sim}26{\mu}M$의 nitric oxide 생성을 증가시키는 것을 알 수 있었다. 종양세포의 괴사 및 NK 세포의 활성화에 관여하는 것으로 알려진 $TNF-{\alpha}$의 생성을 알아본 결과, 고분자 분획인 GMPG-UH와 GMPG-CH는 각각 $3,068.0{\rho}g/ml$$2,975.3 {\rho}g/ml$였고, 저분자에서는 GMPG-UL과 GMPG-CL은 각각 $1,400{\rho}g/ml$를 생성하는 것으로 조사되었다.m}0.25\;Oe$로 전형적인 연자성 재료의 범위로 나타났다. 초투자율, 손실계수, 및 큐리온도는 각각 $2,948{\sim}2,997,\;171{\sim}208,\;191{\sim}202^{\circ}C$로 나타나 Ni-Zn ferrite에서 측정되는 값들과 대동소이했다. 물리적인 특성값(고유저항, 자기유도, 초투자율, 손실계수, 큐리온도 등)으로 미루어보아 각종 microwave 통신기기 core 및 고 투자율 deflection yoke core 등으로 사용이 가능하다.의 쐐기를 사용할 때 MU값이 크다. 결론: 수집된 광자선 빔 데이터를 분석하여 빔데이터의 정확성과 치료계획용 시스템의 계산 정확성을 대략적으로 점검 할 수 있는 기준 값을 제시하였다.동결이 요구되며 본 연구에서 이용된 OPS 동결 방법이 폭넓게 활용될 것으로 사료된다.며 이 때가 최상의 교배 적기로 사료되며, 혈장 progesterone농도가 4.0 ng/ml 이상으로 증가한 날(Bay 0)을 기준으로 하였을 때부터 CI는 혈장 estradiol-$17{\beta}$ peak 후 1일째인 최고치를 나타내었고, CI peak 후 1일째인 Day 0에 혈장 progesterone 농도가 최초로 4.0 ng/ml 이상으로 증가하여 CI가 90% 이상으로 지속된 시기가 최상의 교배 적기임이 확인되었다. 따라서 혈장 progesterone농도 측정으로 정확한 배란 시기 및 교배 적기를 판정할 수 있으나, 시설비가 저렴하고 검사 방법이 간단한 질 세포 검사가 Shih-tzu 견에서 발정 주기, 교배 적기 및 배란 시기의 판정에 응용될 수 있음을 시사하는 결과라고 사료된다.골계가 높은 경향을 보였다. 3) Fe의 함량은 백봉오골계와 연산오골계 모두 다리살이 가슴살보다 더 높았으며, 다리살 중의 Fe 함량을 비교해 보았을 때 백봉오골계가 3.9

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감마선을 이용한 고기능성 히알루론산/연어추출물 제형개발 (Development of High-Functional Hyaluronic Acid/Salmon Extract Formulation Using Gamma-Ray)

  • 권동건;심재구;하만
    • 한국방사선학회논문지
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    • 제12권1호
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    • pp.9-16
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    • 2018
  • 음주 후 숙취는 사람에 따라 증상과 정도가 상이 하지만 일반적으로 갈증, 피로감, 두통, 전신권태, 위장장애, 구토, 설사, 비타민 결핍 등이 나타난다. 이러한 숙취현상은 간세포와 체내에 축적된 알코올 및 알코올에 함유되어 있는 발효 부산물인 에틸아세테이트, 아세트알데히드 등의 전구물질들의 작용에 의해 발생한다. 이에 숙취현상을 해소하기 위한 연구로 연어 추출물 중 정액 또는 정소 추출물인 핵산-당-인산으로 이루어진 고분자이며 다당체인 Polydeoxyribonucleotide(PDRN)과 동일한 Origin, 동일 구조를 가지며 PDRN에 비해 가격이 저렴한 수용성 연어 추출물 분말을 사용하였다. 그리고 D-Glucuronic acid와 N-Acetyl glucosamine으로 구성된 고분자 다당체로 뛰어난 생체 적합성, 점탄성 및 보습력을 보유하고 있어서 숙취현상 중 나타나는 생체수분 감소량 및 피부수분 함유량저하에 대한 부분에 효과가 있어 항산화 및 피부보습효과를 제공하는 히알루론산(Hyaluronic acid)을 감마선으로 조사하여 사용하였다. 연어추출물 분말과 히알루론산 등을 이용하여 조성물을 제조한 후 체내 에탄올, 아세트알데히드 감소량, 혈중 아세트알데히드 농도와 초산 농도를 측정하여 알코올 분해효과를 평가하였고, 피부 수분 증발량과 피부 수분량을 조사하여 피부개선을 평가하고 항산화 및 피부보습효과를 제공하는지 여부를 판단하였다. 이에 에탄올은 연어추출물을 첨가하였을 때가 무첨가에 비해 5배에서 7배의 감소량을 보였고 아세트알데히드 3배에서 5배 이상의 감소량을 보였다. 또한 혈중 아세트알데히드 농도와 초산 농도의 변화에서는 무첨가 대조군에 비해 급격한 저하 변화를 보여 알코올 분해효과가 있음을 확인하여 숙취해소 효과가 있음을 확인할 수 있었다. 그리고 히알루론산 원료를 첨가하여 사용하였을 때 피부 수분함유량이 높았으며, 피부 수분 증발량이 감소됨이 확인되었다. 이에 고분자 다당체인 히알루론산은 뛰어난 점탄성 및 보습력을 보유하고 있어서 숙취현상 중 나타나는 생체수분 감소량 및 피부수분 함유량저하에 효과가 있어 항산화 및 피부보습효과를 제공하는 것으로 사료되어 연어추출물 분말과 히알루론산을 주원료로 하는 조성물이 음주 후 나타나는 숙취현상에 효과가 있다고 할 수 있다.

이중 고온용융 압출 성형된 이중 방출능을 가지는 제형의 개발 (Development of Pharmaceutical Dosage Forms with Biphasic Drug Release using Double-Melt Extrusion Technology)

  • 김동욱;강진양;강창민;박준범
    • 한국산학기술학회논문지
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    • 제17권9호
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    • pp.228-234
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    • 2016
  • 본 이 연구의 목적은 이중 고온용융 압출법을 이용하여 기존의 방법으로 가지기 어려운 이상성의 약물방출 양상을 가지는 제형을 개발하는 것이다. 이 고온용융 압출물은 동회전 능을 가지는 두 개의 스크류가 장착된 압출기를 이용하여 제조되었다. Hydroxpropylmethylcellulose(HPMC) 같은 상대적으로 유리전이 온도가 높은 고분자를 이용하여 1차로 고온용융 압출물이 제조되었고, 이 1차 압출물과 상대적으로 유리전이 온도가 낮은 HPMC-AS(Acceate succinate)나 PEO(polyethlene oxide)를 이용하여 2차로 고온용융 압출물이 제조되었다. 또한 이중 고온용융 압출물과의 비교시험을 위해 같은 조성과 같은 조건하에서 일반적인 한 번의 고온용융 압출물도 제조되었다. 시차주사 열량계를 통해 물리적인 성질이 평가되었고, 미국약전의 제 1법에 따라 $37{\pm}0.5^{\circ}C$와 100 rpm의 조건에서 약물방출 시험이 진행되었으며 그 약물방출은 유사성인자($f_2$)를 이용하여 평가되었다. 시차주사 열량계 결과는 이부프로펜의 결정성이 이중 고온용융 압출법에서나 한번 고온용융 압출법 모두에서 무정형으로 변화된 것을 확인할 수 있었으며, 용출시험에서는 이중 고온용융 압출법에서 더욱 더 이상적인 이부프로펜의 방출을 인공위액(pH 1.2)에서 2시간, 0차 방출을 인공장액(pH 6.8)에서 6시간 동안 확인할 수 있었다. 빠른방출이 요구되는 글리메피라이드의 경우는 이중 고온용융 압출물에서는 60분에 80% 이상의 빠른 약물 방출을 보인 반면, 한번 고온용융 압출물에서는 약물방출이 HPMC와의 상호작용 때문에 느려져서 기준을 만족하지 못했다. 유사성 인자($f_2$) 값도 28.5로 매우 다른 방출을 보여주고 있음이 통계적으로 확인되었다. 이상의 결과들을 종합해 볼 때, 이중 고온용융 압출법은 완건성이 좋은 또 원하는 약물방출을 얻을 수 있는 방법이라 할 수 있다.

설비공학회 분야의 최근 연구 동향 : 2015년 학회지 논문에 대한 종합적 고찰 (Recent Progress in Air-Conditioning and Refrigeration Research : A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2015)

  • 이대영;김사량;김현정;김동선;박준석;임병찬
    • 설비공학논문집
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    • 제28권6호
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    • pp.256-268
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    • 2016
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2015. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering were carried out in the areas of flow, heat and mass transfer, cooling and heating, and air-conditioning, the renewable energy system and the flow inside building rooms. Research issues dealing with air-conditioning machines and fire and exhausting smoke were reduced. CFD seems to be spreading to more research areas. (2) Research works on heat transfer area were carried out in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the economic analysis of GHG emission, micro channel heat exchanger, effect of rib angle on thermal performance, the airside performance of fin-and-tube heat exchangers, theoretical analysis of a rotary heat exchanger, heat exchanger in a cryogenic environment, the performance of a cross-flow-type, indirect evaporative cooler made of paper/plastic film. In the area of pool boiling and condensing, the bubble jet loop heat pipe was studied. In the area of industrial heat exchangers, researches were performed on fin-tube heat exchanger, KSTAR PFC and vacuum vessel at baking phase, the performance of small-sized dehumidification rotor, design of gas-injection port of an asymmetric scroll compressor, effect of slot discharge-angle change on exhaust efficiency of range hood system with air curtain. (3) In the field of refrigeration, various studies were carried in the categories of refrigeration cycle, alternative refrigeration/energy system, system control. In the refrigeration cycle category, a cold-climate heat pump system, $CO_2$ cascade systems, ejector cycles and a PCM-based continuous heating system were investigated. In the alternative refrigeration/energy system category, a polymer adsorption heat pump, an alcohol absorption heat pump and a desiccant-based hybrid refrigeration system were investigated. In the system control category, turbo-refrigerator capacity controls and an absorption chiller fault diagnostics were investigated. (4) In building mechanical system research fields, eighteen studies were reported for achieving effective design of the mechanical systems, and also for maximizing the energy efficiency of buildings. The topics of the studies included energy performance, HVAC system, ventilation, and renewable energies, piping in the buildings. Proposed designs, performance tests using numerical methods and experiments provide useful information and key data which can improve the energy efficiency of the buildings. (5) The field of architectural environment was mostly focused on indoor environment and building energy. The main researches of indoor environment were related to the user and location awareness technology applied dimming lighting control system, the lighting performance evaluation for light-shelves, the improvement evaluation of air quality through analysis of ventilation efficiency and the evaluation of airtightness of sliding and LS window systems. The subjects of building energy were worked on the energy saving estimation of existing buildings, the developing model to predict heating energy usage in domestic city area and the performance evaluation of cooling applied with economizer control. The studies were also performed related to the experimental measurement of weight variation and thermal conductivity in polyurethane foam, the development of flame spread prevention system for sandwich panels, the utilization of heat from waste-incineration facility in large-scale horticultural facilities.

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

  • H.S-Ching;Oh, M.ishi;M.Morimoto
    • 한국우주과학회:학술대회논문집(한국우주과학회보)
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    • 한국우주과학회 1993년도 한국우주과학회보 제2권2호
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    • pp.17-17
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    • 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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