• Journal of Chest Surgery
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• v.31 no.8
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• pp.739-748
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• 1998

Background: It has been well documented that transient occlusion of the coronary artery causes myocardial ischemia and finally cell death when ischemia is sustained for more than 20 minutes. Extensive studies have revealed that ischemic myocardium cannot recover without reperfusion by adequate restoration of blood flow, however, reperfusion can cause long-lasting cardiac dysfunction and aggravation of structural damage. The author therefore attempted to examine the effect of postischemic reperfusion on myocardial ultrastructure and to determine the rationales for recanalization therapy to salvage ischemic myocardium. Materials and methods: Young Holstein-Friesian cows(130∼140 Kg body weight; n=40) of both sexes, maintained with nutritionally balanced diet and under constant conditions, were used. The left anterior descending coronary artery(LAD) was occluded by ligation with 4-0 silk snare for 20 minutes and recanalized by release of the ligation under continuous intravenous drip anesthesia with sodium pentobarbital(0.15 mg/Kg/min). Drill biopsies of the risk area (antero-lateral wall) were performed at just on reperfusion(5 minutes), 1-, 2-, 3-, 6-, 12-hours after recanalization, and at 1-hour assist(only with mechanical respiration and fluid replacement) after 12-hour recanalization. The materials were subdivided into subepicardial and subendocardial tissues. Tissue samples were examined with a transmission electron microscope (Philips EM 300) at the accelerating voltage of 60 KeV. Results: After a 20-minute ligation of the LAD, myocytes showed slight to moderate degree of ultrastructural changes including subsarcolemmal bleb formation, loss of nuclear matrix, clumping of chromatin and margination, mitochondrial destruction, and contracture of sarcomeres. However, microvascular structures were relatively well preserved. After 1-hour reperfusion, nuclear and mitochondrial matrices reappeared and intravascular plugging by polymorphonuclear leukocytes or platelets was observed. However, nucleoli and intramitochondrial granules reappeared within 3 hours of reperfusion and a large number of myocytes were recovered progressively within 6 hours of reperfusion. Recovery was apparent in the subepicardial myocytes and there were no distinct changes in the ultrastructure except narrowed lumen of the microvessels in the later period of reperfusion. Conclusions: It is likely that the ischemic myocardium could not be salvaged without adequate restoration of coronary flow and that the microvasculature is more resistant to reversible period of ischemia than subendocardium and subepicardium. Therefore, thrombolysis and/or angioplasty may be a rational method of therapy for coronarogenic myocardial ischemia. However, it may take a relatively longer period of time to recover from ischemic insult and reperfusion injury should be considered.

• Journal of Life Science
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• v.8 no.5
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• pp.509-519
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• 1998

The effect of N-Nitrosodimethylamine(NDMA) on the glycoconjugates of rat lingual salivary gland was examined by prelectin histochemical methods. Sprague-Dawley rats weighing about 250-300g were divided into control and experimental groups. Each rat of experimental groups was administrated NDMA(17mg/kg) orally and sacrificed in 3, 6, 12, 24, 48, 72, 96 and 120 hours after NDMA administration. The regional differences and change of glycoco-njugates were elucidated by prelectin histochemical methods, such as periodic acid Schiff's(PAS) reaction, alcian blue (AB) pH 2.5, AB pH 0.4, AB pH 2.5-PAS, aldehyde fuchsin(AF) pH 1.7-AB pH 2.5 and high iron diamine(HID)-AB pH 2.5 staining. The major morphological changes in the von Ebner’s gland of NDMA administrated groups were withering and des-truction of serous acini, diminution and disappearance of cytoplasmic granules and vacuolation in cytoplasm of serous cells, and mucinous changes of duct epithelial cells. These changes were noted in NDMA administrated groups for 12 to 72 hours. In the lingual mucous gland of NDMA administrated groups, the major morphological changes were enlargement, fusion and destruction of mucous acini, loss of cytoplasmic granules and vacuolated generation in cytop-lasm of mucous cells, and mucinous change of duct epithelial cells. These changes were severe in NDMA administra-ted groups for 12 to 72 hours. In NDMA administrated groups of lingual von Ebner's gland for 12 and 72 hours, the neutral glycoconjugates be-come diminished remarkably compared to the control group. The decreased amount of neutral glycoconjugates tended to be gradually recovered from 96 hours group. The acidic glycoconjugates which were not detected in control group were found in a few serous cells of these gland of NDMA administrated groups for 6 to 48 hours and 120 ho-urs. The remarkable decrease of neutral and acidic glycoconjugates was observed in the lingual mucous glands 3, 24 and 48 hours after NDMA administration, and the striking decrease of acidic glycoconjugates was found in 72 hours groups. Among acidic glycoconjugates, sulfated glycoconjugates tended to decrease in NDMA administrated groups for 72 hours, while sialic glycoconjugates were increased in NDMA administrated groups for 3, 12 and 48 hours.

• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.716-723
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• 1995

The fucoidan purified from Korean brown seaweed, Ecklonia stolonifera was characterized on molecular structure and blood anticoagulant activities. Extraction was conducted at $100^{\circ}C$ with water and repeated twice. The crude fucodian was 151.1g out of 20.0 kg of Ecklonia stolonifera. The Fucoidan-1, which was purified from crude fucoidan using calcium chloride and cetyl pyridium chloride (CPC), was 35.2% against crude fucoidan. Fucoidan-5 was obtained approximately 28.1% from Fucoidan-1 through DEAE-Toyopearl 650 M ion-exchange column chromatography and showed one band by cellulose acetate electrophoresis. The molecular weight of Fucoidan-5 was estimated to be about 21,000∼23,000 dalton by Sephacryl S-300 gel filtration chromatography. Fucoidan-5 consists of 35.7% of fucose and 4.3% of galactose and the molar ratio of fucose and sulfate was about one to one. IR spectrum of Fucoidan-5 showed absorption at $1240\;cm^{-1}\;and\;850\;cm^{-1}$ and specific rotation value, $[\alpha]$, was $[\alpha]$. These results suggests that the sulfate maybe bind at $C_{4}$ carbon on ${\alpha}-L-fucose$. Gas chromatograph of methyl alditol acetate revealed that Fucoidan-5 is a fucose containing sulfated polysaccharide with $({\alpha}l-2)\;or\;({\alpha}l-2)$ glycosidic linkage. Anti-thrombin activity of the Fucoidan-5 was estimated as 1.4 time stronger than heparin. From above results, the purification methods using CPC and ion exchange chromatography is effective tools for obtaining highly purified fucoidan from Gompi, Ecklonia stolonifera.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.2
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• pp.100-108
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• 2000

High sodium contents in food-waste compost(FWC) is the greatest limitation to recycle it to arable lands in Korea. The effects of the FWC application to paddy soil on the growth of rice plants, cationic balance in plants, and the sodicity of soil have been studied in pot trials. The effects of FWC application were compared with those of NaCl compound and swine manure compost(SMC) application. $Na_2O$ contents of FWC were high as 2.2%. Immediately after transplanting, rice plants in three treatments showed severe wilting in the order of 40Mg FWC $ha^{-1}$ > NPK+900kg $NaClha^{-1}$ > 20Mg FWC $ha^{-1}$. The high EC value and volatile acid contents of soil solution were regarded as the cause of severe wilting of young rice plants. Increase of NaCl application rate upto $900kgha^{-1}$ showed no significant reduction of dry matter yield at harvesting stage. Regardless of application rates FWC reduced the dry matter yield at harvesting stage, while SMC increased it with increase of application rates upto $40Mgha^{-1}$. In NPK+NaCl and FWC treatments, Na contents and equivalent ratio in plants increased linearly with increase of Na application rates. Between Na and K equivalent ratio negative correlation with high significance was shown. In contrast to much difference of Na, K, and Na/K equivalent ratio among treatments, little difference of Na+K indicated the physiological substitution of Na for K in rice plants. Na use efficiency in NPK+NaCl and FWC treatments showed 12-22%.

• Journal of Society of Preventive Korean Medicine
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• v.8 no.2
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• pp.141-156
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• 2004

Objectives : JianTeng-Yuan(交藤圓) is said to be a prescription for preservation of health in ${\ulcorner}$HuaTuo ZhongZangJing(華陀 中藏經)${\lrcorner}$. It is known to have the effect of Bu-Shen(補腎: strengthening kidney) and Yi-Shou(益壽: prolonging the span of one's life). This study investigates whether JTY is effective on inhibition of oxidation stress. Methods : Sprague-Dawley Rats(12-week-old, weight $300{\pm}20g$) were divided into 3 groups. Normal group(n=8) was injected PBS(1ml/body, s.c) at the back neck's skin. Control group(n=8) was injected D-galactose(50mg/kg, 1ml PBS/body, s.c) to induce pathological animals. JTY group was injected the same treatment for the Control group, and fed containing JTY(10%). The whole groups were treated 1 time per day for 6 weeks. After rats were sacrificed and anti-oxidant enzyme(SOD, CAT, G-px) activity, GSH quantity of RBC and tissue(heart, liver and kidney), plasma Vit-C quantity were examined. Besides, the MDA levels of liver and kidney, lipofuscin of heart and endurance of erythrocyte membrane were measured. Results : In the JTY group, RBC's SOD activity decline was halted by 21% of the normal level, compared to the control group ; G-px activity(unit/g of Hb) increased significantly, compared to the normal group ; and the level of Vit-C in plasma increased by 16%. Heart's SOD activity was kept at the same level as that of the normal group ; and CAT activity decline was halted by 26%. Kidney's CAT and G-px activities were kept at the same level as that shown in the normal group, implying the existence of halting effect. Liver also showed a slight halting effect against the decline of anti-oxidant ability, but the effect was not significant(a=0.05). A comparison between the levels of peroxide in SD rats showed that the level of TBARS in plasma increased significantly in the control group and that it was normal in the JTY group. The livers in the JTY group, compared to those in the control group, showed 36% halting effect of the normal level while their kidney's indicated the level significantly lower than the normal level. Heart's lipofuscin increased significantly in the control group, but was alike in both the JTY and the normal groups. Endurance of erythrocyte membrane(%) decreased significantly in the control group while it was kept at the similar level in both the JTY and the normal groups, indicating the halting effect. Conclusions : This study suggests that JTY is effective to defend oxidation stress caused by D-galactose in the animals. It showed that the anti-oxidant ability was maintained and strengthened. On the other hand, it reduced the level of peroxide in animals. In sum, JTY appeared to have the equilibrium normal physiological function in SD rat.

• Journal of Preventive Medicine and Public Health
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• v.28 no.4 s.51
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• pp.863-873
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• 1995

This report describes a preperation and characterization of canine blood lead(Pb) standard reference material(SRM). Three adult beagle dogs(A, B, and C)were orally dosed with gelatin capsules containing $Pb(NO_3)_2$, equivalent to $10\sim80mg$ Pb/kg body weight. Blood was drawn 24 hours after the dose from the cephalic vein into lead free 500ml Pyrex beaker in which EDTA.K was contained as an anticoagulant. The amount of lead given to individual dog was varied arbitrarily. Three month later, 3 canine animals were orally dosed with lead secondarily to make mixed SRM(D1) which was mixed different concentrations of lead in bloods with A1, B1, and C1 in vitro. The SRMs for A, B, C, A1, B1, C1, and D1 were distributed 2ml each into more than 300 lead free bottles, and were stored in refregerator at $4^{\circ}C$. The amount of lead in canine whole blood samples were determined using a Varian 30A atomic absorption spectrophotometer(AAS) with a model GTA-96 graphite tube atomizer with D2 background correction and a Hitachi Z-8100 AAS with Zeeman background correction. The sensitivity and detection limits for lead determination of Varian 30A were $0.46{\mu}g/L,\;0.34{\mu}g/L,\;and\;0.56{\mu}g/L,\;0.14{\mu}g/L$ of Hitachi Z-8100, respectively. Day to day variations in determination of blood lead concentration in a certain sample were $31.11{\pm}1.36{\mu}g/100ml$ by Varian 30A, and $33.08{\pm}0.82{\mu}g/100ml$ by Hitachi Z-8100, showing the difference of 3% between the two results. At the blood lead concentrations of $56.31{\pm}1.98{\mu}g/100ml(A),\;40.89{\pm}0.80{\mu}g/100ml(B),\;59.01{\pm}1.38{\mu}g/100ml(C)$, the precisions of replicated measurements by AAS were 3.52%, 1.96%, and 2.34%, respectively. Coefficient variation(CV) of SRMs(A, B, and C) within a standard sample were ranged from 0.92% to 7.50%, and those between 5 standard samples were 1.21%, 2.64%, and 1.11%, respectively, showing inter-vial variation of $1{\mu}g/100ml$. Lead levels in SRMs during one month storage were unchanged. The overall recoveries were $89.6\sim100.4%,\;91.6\sim101.9%,\;90.3\sim100.0%$ for A, B, and C SRMs, means were $56.46{\pm}2.69{\mu}g/100ml,\;39.35{\pm}1.89{\mu}g/100ml,\;57.40{\pm}2.31{\mu}g/100ml$, and measurement ranges were$52.88{\pm}59.26{\mu}g/100ml,\;37.47{\pm}41.68{\mu}g/100ml,\;54.80{\pm}60.69{\mu}g/100ml$, respectively. Those results were laid within confidence limits values. The lead concentrations in the mixed sample(D1) stored over one month period were ranged from $32.76{\mu}g/100ml\;to\;33.54{\mu}g/100ml$, with CV ranging from 1.2% to 2.7%. The results were similiar to each of single samples(A1, B1, and C1) in respect of homogeneity and stability. Results of the mixed blood sample analysed after 1 month storage at $4^{\circ}C$ by four other laboratories(L1, L2, L3, L4) were similar with those of our laboratory($L5;31.18{\pm}0.24{\mu}g/100ml$, acceptable range by $CDC;25.18\sim37.18{\mu}g/100ml$), showing the concentrations of $25.91{\pm}1.19{\mu}g/100ml(L1),\;34.16{\pm}0.22{\mu}g/100ml(L2),\;35.68{\pm}0.85{\mu}g/100ml(L3),\;30.95{\pm}0.46{\mu}g/100ml(L4)$ in a each samples.

• Journal of the Korea Organic Resources Recycling Association
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• v.30 no.4
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• pp.67-83
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• 2022

Biochar is a carbon material produced through the pyrolysis of agricultural biomass with limited oxygen condition. It has been suggested to enhance the carbon sequestration and mineralization of soil carbon. Objective of this study was to investigate soil potential carbon mineralization and carbon dioxide(CO₂) emissions in different soils cooperated with barely straw and livestock manure biochars in the closed chamber. The incubation was conducted during 49 days using a closed chamber. The treatments consisted of 2 different biochars that were originated from barley straw and livestock manure, and application amounts were 0, 5, 10 and 20 ton ha^-1 with different soils as upland, protected cultivation, converted and reclaimed. The results indicated that the TC increased significantly in all soils after biochar application. Mineralization of soil carbon was well fitted for Kinetic first-order exponential rate model equation (P<0.001). Potential mineralization rate ranged from 8.7 to 15.5% and 8.2 to 16.5% in the barely straw biochar and livestock manure biochar treatments, respectively. The highest CO₂ emission was 81.94 mg kg^-1 in the upland soil, and it was more emitted CO₂ for barely straw biochar application than its livestock biochar regardless of their application rates. Soil amendment of biochar is suitable for barely straw biochar regardless of application rates for mitigation of CO₂ emission in the cropland.

• Korean Journal of Radiology
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• v.2 no.1
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• pp.28-36
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• 2001

Objective: To provide a systematic overview of the effects of various parameters on contrast enhancement within the same population, an animal experiment as well as a computer-aided simulation study was performed. Materials and Methods: In an animal experiment, single-level dynamic CT through the liver was performed at 5-second intervals just after the injection of contrast medium for 3 minutes. Combinations of three different amounts (1, 2, 3 mL/kg), concentrations (150, 200, 300 mgI/mL), and injection rates (0.5, 1, 2 mL/sec) were used. The CT number of the aorta (A), portal vein (P) and liver (L) was measured in each image, and time-attenuation curves for A, P and L were thus obtained. The degree of maximum enhancement (Imax) and time to reach peak enhancement (Tmax) of A, P and L were determined, and times to equilibrium (Teq) were analyzed. In the computed-aided simulation model, a program based on the amount, flow, and diffusion coefficient of body fluid in various compartments of the human body was designed. The input variables were the concentrations, volumes and injection rates of the contrast media used. The program generated the time-attenuation curves of A, P and L, as well as liver-to-hepatocellular carcinoma (HCC) contrast curves. On each curve, we calculated and plotted the optimal temporal window (time period above the lower threshold, which in this experiment was 10 Hounsfield units), the total area under the curve above the lower threshold, and the area within the optimal range. Results: A. Animal Experiment: At a given concentration and injection rate, an increased volume of contrast medium led to increases in Imax A, P and L. In addition, Tmax A, P, L and Teq were prolonged in parallel with increases in injection time The time-attenuation curve shifted upward and to the right. For a given volume and injection rate, an increased concentration of contrast medium increased the degree of aortic, portal and hepatic enhancement, though Tmax A, P and L remained the same. The time-attenuation curve shifted upward. For a given volume and concentration of contrast medium, changes in the injection rate had a prominent effect on aortic enhancement, and that of the portal vein and hepatic parenchyma also showed some increase, though the effect was less prominent. A increased in the rate of contrast injection led to shifting of the time enhancement curve to the left and upward. B. Computer Simulation: At a faster injection rate, there was minimal change in the degree of hepatic attenuation, though the duration of the optimal temporal window decreased. The area between 10 and 30 HU was greatest when contrast media was delivered at a rate of 2 3 mL/sec. Although the total area under the curve increased in proportion to the injection rate, most of this increase was above the upper threshould and thus the temporal window was narrow and the optimal area decreased. Conclusion: Increases in volume, concentration and injection rate all resulted in improved arterial enhancement. If cost was disregarded, increasing the injection volume was the most reliable way of obtaining good quality enhancement. The optimal way of delivering a given amount of contrast medium can be calculated using a computer-based mathematical model.

• Journal of Chest Surgery
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• v.39 no.12 s.269
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• pp.879-890
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• 2006

Background: The dysfunction of multiple organs is found to be caused by reactive oxygen species as a major modulator of microvascular injury after hemorrhagic shock. Hemorrhagic shock, one of many causes inducing acute lung injury, is associated with increase in alveolocapillary permeability and characterized by edema, neutrophil infiltration, and hemorrhage in the interstitial and alveolar space. Aggressive and rapid fluid resuscitation potentially might increased the risk of pulmonary dysfunction by the interstitial edema. Therefore, in order to improve the pulmonary dysfunction induced by hemorrhagic shock, the present study was attempted to investigate how to reduce the inflammatory responses and edema in lung. Material and Method: Male Sprague-Dawley rats, weight 300 to 350 gm were anesthetized with ketamine(7 mg/kg) intramuscular Hemorrhagic Shock(HS) was induced by withdrawal of 3 mL/100 g over 10 min. through right jugular vein. Mean arterial pressure was then maintained at $35{\sim}40$ mmHg by further blood withdrawal. At 60 min. after HS, the shed blood and Ringer's solution or 5% albumin was infused to restore mean carotid arterial pressure over 80 mmHg. Rats were divided into three groups according to rectal temperature level($37^{\circ}C$[normothermia] vs $33^{\circ}C$[mild hypothermia]) and resuscitation fluid(lactate Ringer's solution vs 5% albumin solution). Group I consisted of rats with the normothermia and lactate Ringer's solution infusion. Group II consisted of rats with the systemic hypothermia and lactate Ringer's solution infusion. Group III consisted of rats with the systemic hypothermia and 5% albumin solution infusion. Hemodynamic parameters(heart rate, mean carotid arterial pressure), metabolism, and pulmonary tissue damage were observed for 4 hours. Result: In all experimental groups including 6 rats in group I, totally 26 rats were alive in 3rd stage. However, bleeding volume of group I in first stage was $3.2{\pm}0.5$ mL/100 g less than those of group II($3.9{\pm}0.8$ mL/100 g) and group III($4.1{\pm}0.7$ mL/100 g). Fluid volume infused in 2nd stage was $28.6{\pm}6.0$ mL(group I), $20.6{\pm}4.0$ mL(group II) and $14.7{\pm}2.7$ mL(group III), retrospectively in which there was statistically a significance between all groups(p<0.05). Plasma potassium level was markedly elevated in comparison with other groups(II and III), whereas glucose level was obviously reduced in 2nd stage of group I. Level of interleukine-8 in group I was obviously higher than that of group II or III(p<0.05). They were $1.834{\pm}437$ pg/mL(group I), $1,006{\pm}532$ pg/mL(group II), and $764{\pm}302$ pg/mL(group III), retrospectively. In histologic score, the score of group III($1.6{\pm}0.6$) was significantly lower than that of group I($2.8{\pm}1.2$)(p<0.05). Conclusion: In pressure-controlled hemorrhagic shock model, it is suggested that hypothermia might inhibit the direct damage of ischemic tissue through reduction of basic metabolic rate in shock state compared to normothermia. It seems that hypothermia should be benefit to recovery pulmonary function by reducing replaced fluid volume, inhibiting anti-inflammatory agent(IL-8) and leukocyte infiltration in state of ischemia-reperfusion injury. However, if is considered that other changes in pulmonary damage and inflammatory responses might induce by not only kinds of fluid solutions but also hypothermia, and that the detailed evaluation should be study.

• Journal of Biomedical Engineering Research
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• v.6 no.2
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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.