• 제목/요약/키워드: HOST

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내독소처치 흰쥐에서 Tumor Necrosis Factor-$\alpha$치 상승에 따른 폐손상 악화 및 35 kDa 단백질 합성 (Lung Injury Indices Depending on Tumor Necrosis Factor-$\alpha$ Level and Novel 35 kDa Protein Synthesis in Lipopolysaccharide-Treated Rat)

  • 최영미;김영균;권순석;김관형;문화식;송정섭;박성학
    • Tuberculosis and Respiratory Diseases
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    • 제45권6호
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    • pp.1236-1251
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    • 1998
  • 연구배경 : 급성폐손상의 병태생리학적 기전에는 염증세포들이 분비하는 다양한 염증성 매개물질들이 매우 중요한 역할을 한다. 이중 특히 tumor necrosis factor-$\alpha$ (TNF-$\alpha$) 는 다른 염증세포들의 화학주성 및 각종 염증성 매개물질 분비에 영향을 미치는 proin-flammatory cytokine으로 작용하는 한편, 직접적으로 세포손상을 야기시키는 세포독성 cytokine으로도 작용하는데, 급성폐손상에서 TNF-$\alpha$와 폐조직 손상과의 직접적인 관련성에 대해서는 아직 구체적으로 확인된 바가 많지 않다. 또한, 최근에 생체내 방어기전으로 스트레스 단백질에 대한 관심이 높아지면서, 단핵구에 내독소를 처치하거나, 동물에 내독소를 투여하기 전에 미리 스트레스 단백질을 합성시킨 경우, 내독소에 의한 손상을 감소시켜 준다는 연구가 보고되었지만, 내독소 자극 자체만으로 스트레스 단백질 합성이 유도되는지는 아직 분명하지 않다. 이에 저자들은 내독소 유도성 급성 폐손상에서 TNF-$\alpha$ 분비와 폐조직 손상을 포함한 일련의 염증반응과의 관계를 분석하고, 생체내 내독소 자극에 대하여 폐포대식세포에서 스트레스 단백질을 포함한 새로운 단백질 합성이 유도되는지 여부를 분석하고자 하였다. 연구방법 : 흰쥐의 기관내로 내독소를 투여한 후 시간별로 기관지폐포세척액내 TNF-$\alpha$농도, 염증세포 백분율 변화, 병리조직학적 소견을 관찰하고, 또한 각 시간대의 폐포대식세포에서 sodium dodesyl sulfate-polyacrylamide gel electrophoresis와 inducible heat stress protein72에 대한 면역화학염색을 시행하여 단백질 합성양상을 분석하는 한편, 폐포대식세포에 다양한 농도의 내독소 자극과 열처리를 가한 후, 배양상층액에서 tumor necrosis factor-a 농도를 측정하고, 폐포대식세포의 단백질 합성양상을 분석하였다. 연구결과 : 내독소 투여 후 tumor necrosis factor-$\alpha$는 첫 1시간째부터 현저하게 증가하여 (p< 0.0001) 3시간째 최고치에 이르렀고 6시간째는 감소하기 시작하여 12시간째는 정상 대조군 수준으로 감소하였다. 내독소 투여 후 염증세포 백분율의 변화는 2시간째부터 시작하여 6시간째 최고에 이르러 12시간째까지 지속하였으며, 장시간째에 정상 대조군 수준으로 회복하였다. 병리조직학적 소견상 폐손상 지표 점수는 내독소 투여후 6시간째 최고치에 이르러 24 시간째까지 지속하였다. 내독소 투여 후 분리한 폐포대식세포에서 첫 1시간째부터 장시간째까지 정상 대조군에서는 관찰할 수 없던 35kDa의 새로운 단백질 띠가 관찰되었으며, 면역화학염색상 inducible heat stress protein72는 관찰되지 않았다. 내독소 자극을 가하지 않은 정상 대조세포군에 비해 내독소 자극을 가한 세포군의 배양상층액에서 tumor necrosis factor-$\alpha$ 농도가 유의하게 높았으며 (p<0.001), 내독소 자극만 가한 세포군에 비해 열충격 전처치후 내독소 자극을 가한 세포군의 배양상층액에서 tumor necrosis factor-$\alpha$ 농도가 10 ${\mu}g/ml$ 내독소 자극군만 제외하고 모두 유의하게 감소하였다 (p<0.05). 내독소 자극만 가한 세포군은 10 ${\mu}g/ml$의 고농도에서만 35 kDa 의 단백질 띠가 합성되었고 inducible heat stress protein72는 관찰되지 않았다. 열충격 전처치후 내독소 자극을 가한 세포군은 모두 inducible heat stress protein72가 관찰되었다. 결 론 : 기관내 내독소 투여에 의한 급성 폐손상에서 tumor necrosis factor-$\alpha$는 폐손상 정도와 밀접한 관련이 있다. 또한 내독소 자극에 의해서는 폐포대식세포에서 inducible heat stress protein72 합성이 유도되지 않으며, 35 kDa의 새로운 단백질 합성이 유도되었는데, tumor necrosis factor-$\alpha$ 농도 및 병리조직소견과의 관계를 볼 때, 급성 폐손상에 있어 35 kDa 단백질이 방어적인 역할을 담당하지는 않을 것으로 보이며, 이에 대해서는 향후 더 연구가 필요할 것으로 생각된다.

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산화질소 공여물과 산화질소 합성효소 길항제가 백서 폐미세혈관 내피세포 산화제 손상에 미치는 영향 (The Effect of Nitric Oxide Donor or Nitric Oxide Synthase Inhibitor on Oxidant Injury to Cultured Rat Lung Microvascular Endothelial Cells)

  • 장준;;김세규;김성규;이원영;강경호;유세화;채양석
    • Tuberculosis and Respiratory Diseases
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    • 제45권6호
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    • pp.1265-1276
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    • 1998
  • 연구배경 : NO는 생체내에서 생성되는 유리 반응기로서 혈관 긴장도외 완화, 혈소판 응집 저지, 혈관 내피세포에 대한 백혈구 유착 방해, 감염에 대한 숙주 방어 등에서 중요한 역할을 한다. NO는 전이 금속(transition metal), 산소, 기타 반응기 등과 쉽게 반응하므로 여러 생체내 반응에 관여하여 산화제 손상을 촉진시키거나 감소시킬 가능성이 제기되었다. 급성 폐손상 및 급성 호흡곤란 증후군에서는 폐혈관 내피세포 및 호중구의 상호작용 및 산화제 손상이 매우 중요한 병인으로 알려져 있으며, NO를 급성 호흡곤란 증후군에서 흡입하여 치료하는 것은 산화제에 의한 혈관 내피세포 손상에서 외부로부터 NO를 공급하는 상황이다. 본 연구에서는 외인성 NO의 공여나 내인성 NO 억제가 산화제에 의한 폐미세혈관 내피세포의 손상을 악화시키거나 완화시킬 수 있는지를 관찰하였다. 방 법 : 산화제에 의한 세포손상은 백서 폐미세혈관 내피세포에 과산화수소를 생성하는 glucose oxidase(GO)를 투여하여 야기시키고 이를 $^{51}Cr$ 방출 측정으로 평가하였다. 산화제에 의한 폐혈관 내피세포의 손상에 외인성 NO가 미치는 영향은 NO 공여물인 SNAP 혹은 SNP를 산화제와 동시에 투여하여 평가하였다. 산화제에 의한 폐혈관 내피세포의 손상에 내인성 NO 억제가 미치는 영향은 NOS 길항제인 L-NMMA을 추가로 투여하여 평가하였다. INF-$\gamma$, TNF-$\alpha$ LPS 등으로 내인성 NO 생성을 자극한 후 L-NMMA의 효과도 관찰하였으며, NO 공여물이나 내피세포로 부터의 NO생성은 nitrite 측정으로 평가하였다. 결 과 : 백서 폐 미세혈관 내피세포에서 $^{51}Cr$ 방출이 GO 5mU/ml에서 $8.7{\pm}0.5%$, 10 mU/ml에서 $14.4{\pm}2.9%$, 15 mU/ml에서 $32.3{\pm}2.9%$, 20 mU/ml에서 $55.5{\pm}0.3%$. 30 mU/ml에서 $67.8{\pm}0.9%$로 GO 15 mU/ml 이상에서 대조군의 $9.6{\pm}0.7%$에 비하여 유의하게 증가하였으며 (P<0.05; n=6). 이에 0.5mM L-NMMA를 추가하여도 영향이 없었다. INF-$\gamma$ 500 U/ml, TNF-$\alpha$ 150 U/ml, LPS 1 ${\mu}g/ml$을 배양액에 첨가하여 24시간 경과시 배양액 중 nitrite 농도가 $3.9{\pm}0.3\;{\mu}M$로 증가하였으며, 이에 L-NMMA 0.5 mM을 첨가하면 $0.2{\pm}0.l\;{\mu}M$로 유의하게 억제되었다(p<0.05 ; n=6). INF-$\gamma$, TNF-$\alpha$ LPS 자극후 GO에 의한 $^{51}Cr$ 방출에 L-NMMA는 영향을 주지 않았다. GO 20 mU/ml에 의한 $^{51}Cr$ 방출이 SNAP 100 ${\mu}M$의 추가로 대조군 수준으로 현저히 억제되었으나, SNP, potassium ferrocyanide, potassium ferricyanide 등의 추가는 영향이 없었다. Hanks' balanced salt solution(HBSS) 중의 SNAP 100 ${\mu}M$로 부터 4 시간 동안 nitrite가 $23.0{\pm}1.0\;{\mu}M$ 농도로 축적되었으나, SNP는 1 mM에서도 nitrite가 검출되지 않았다. SNAP은 HBSS 중의 GO가 과산화수소를 시간 경과에 따라 생성하는데 영향이 없었다. 결 론 : 결론적으로 폐미세혈관 내피세포에서 GO에 의하여 생성되는 과산화수소로 산화제 손상을 야기하였으며, NO 공여물인 SNAP으로부터 제공된 외연성 NO가 산화제 손상을 방지하고 이 보호효과는 NO 방출 능력에 의할 가능성이 시사되었다. 따라서 생체내 환경에 따라 외인성 NO가 내피세포에 대한 산화제 손상에 보호 효과가 있을 수 있다고 추정된다.

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벼줄무늬잎마름바이러스의 대 발생과 발생 요인 (Severe Outbreak of Rice Stripe Virus and Its Occurring Factors)

  • 김정수;이관석;김창석;최홍수;이수헌;김미경;곽해련;남문;김정선;노태환;강미형;조점덕;김진영;강효중;한종우;김병련;정성수;김주희;고숙주;이중환;김태성
    • 농약과학회지
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    • 제15권4호
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    • pp.545-572
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    • 2011
  • 벼줄무늬잎마름바이러스(Rice stripe virus, RSV)에 대하여 유전자 진단기술인 RT-PCR과 VC/RT-PCR 기술을 개발하였다. ELISA 진단법은 유묘 검정법 보다 평균 40.5%, RT-PCR 진단법은 ELISA 진단법 보다 21%의 진단 효율이 높았다. 2009년 경기도 김포, 평택, 시흥 지역에서 채집한 애멸구의 보독충률을 VC/RT-PCR 진단법과 ELISA 진단법으로 검정한 결과 전체 평균 보독충률은 9.2%로 동일하였다. 벼줄무늬잎마름바이러스가 감염된 벼 포장에서 수집한 13개 분리주의 유전자 유연성은 RNA1과 RNA2는 중국+한국, 중국+한국+일본의 2개의 군으로 구분되었다. 또한 병원성 발현에 관여하는 RNA3는 중국, 중국+한국, 한국+일본의 3개 군으로, RNA4는 중국, 한국, 중국+한국+일본, 한국+일본의 4개의 군으로 구분되었다. 경기도 등 7개 도의 주요 28개의 재배지역에서 채집한 애멸구의 전국 평균 보독충률은 2008년 4.3%, 2009년 6.1%, 2010년 7.2%로 매년 상승하였다. 2008년에는 경기도가 11.3%로 가장 높았으며, 2009년에는 전라남도가 20.1%, 2010년에는 경기도 12.0%, 충청북도 14.2%로 가장 높았다. 보독충률이 가장 높았던 지역은 2008년에는 전북 부안 지역이 22.1%, 2009년에는 전남 완도와 진도가 36%, 2010년에는 충북 보은이 30.0%였다. 월동 애멸구의 전국 평균 밀도는 2008년 13.1 마리, 2009년 13.9 마리, 2010년 5.6 마리였으며, 월동 애멸구의 밀도는 전북 부안 지역이 2008년 39.1 마리, 2009년 60.4 마리로 가장 높았으며, 2010년에는 경기 평택 지역이 14.0 마리로 가장 높았다. 2008년 RSV 발생은 전남 진도, 해남 지역을 중심으로 869 ha가 발생하였으며, 2009년에는 전국적으로 21,541 ha가 발생하였으며, 특히 서해안 지역의 경우 경기도, 인천시, 충남, 전북, 전남의 19개 시군, 39개 읍면, 53개 리에서 3,025 포장을 조사한 결과 55.2%가 부분 고사 이상의 피해가 발생하였다. 2008년부터 3년간 전북 부안, 전남 진도 등에서 월동 애멸구의 시기별 발육을 조사한 결과 5월 20일에서 6월 10일 경에는 월동 후 1세대는 대부분 3령과 4령 이었으며 성충은 6월 하순경에 최성기였다. 2009년 5월 31에서 6월 1일에 태안, 서산, 부안, 신안, 진도 등에서 공중 포충망에 채집한 애멸구는 모두 성충이었으며 밀도는 태안 지역이 963 마리, 서천 919 마리, 신안 819 마리 등으로 매우 많이 포획되었으며, 공중 포충망에 채집된 애멸구는 국내에서 월동한 애멸구 집단이 아니고 중국에서 비래한 애멸구 집단으로 확인되었다. 2010년에는 5월 중순에서 6월 중순까지 공중 포충망에 애멸구 성충이 거의 채집되지 않았다. 2009년 충남 홍성, 전북 부안, 전남 영광 등 서해안 8개 지역의 공중 포충망에서 채집한 애멸구 성충의 RSV 보독충률은 2.1%에서 9.5%로 변이가 컸으며, 보령이 9.5%로 가장 높았으며, 다음으로 충남 홍성 7.9%, 전남 영광 6.5%, 충남 태안 6.4%였다. 애멸구 비래 후 약 10일 후에 공중 포충망 주변의 논에 심겨진벼에 대하여 RSV의 유전자 진단 결과 태안 84.6%, 부안 65.4%, 진도 92.9% 이었으며, 평균 감염률은 81% 이었다. 보리는 RSV의 주요 월동 기주식물로 알려져 있으나 RSV의 감염률은 경기 평택 등 전국에서 530점을 채집하여 유전자 진단 결과 감염률이 0.2%로 매우 낮았다. RSV의 새로운 자연 기주식물로 29종이 확인되었다. 하계 일년생 식물은 조개풀 등 13종, 동계 일년생은 들묵새 등 11종, 다년생으로는 우산잔디 등 5종 이었다. RSV 감염률은 동계 일년생인 들묵새 24.9%, 하계 일년생인 바랭이 44.9%, 물피 95.2%, 가을강아지풀 65.5%이었으며, 다년생인 물억새는 33.3%였다. RSV에 감수성인 동진1호 등 8개 품종과 저항성인 삼광벼 등 17개 품종에 대하여 2009년 부안, 익산, 김제 지역의 자연 포장에서 병징 발현 여부를 조사한 결과 감수성 8개 품종은 모두 감수성이었으며, 진성 저항성 품종 중 온누리 등 12개 품종은 감수성이었으며 삼광벼 등 5개 품종은 포장 저항성이었다. RSV에 저항성인 남평벼 등 4 품종과 감수성인 동진1호 등 3 품종을 대상으로 바이러스를 인공접종한 결과 RSV의 병징 발현률은 감수성 품종의 경우 평균 53.3%이었으며 저항성 품종의 경우 평균 34.0%로 19.3% 낮았다. 감수성인 흑남벼와 저항성인 남평벼를 이용하여 병징 발현률과 바이러스 감염률을 조사한 결과 병징 발현률은 흑남벼 28%, 남평벼 12%로 감수성 품종이 병징 발현률이 2배 이상 높았다. 그러나 체내 바이러스 감염률은 흑남벼 85%, 남평벼 97%로 오히려 저항성 품종에서 12%의 높은 감염률을 보였다. 저항성 품종에서의 저항성 기작은 병징 발현에 대한 저항성이며 바이러스 증식에서는 저항성이 아니었다. RSV에 저항성 품종인 남평벼, 온누리와 감수성 품종인 동진1호, 운광벼를 이용하여 생육시기별로 인공접종하여 수량 감소를 2008년부터 3년간 조사한 결과 감수성 품종에서는 주당 수량을 보면 유묘기 감염시 7.8 g, 분얼기 감염시 8.5 g, 최고 분얼기 감염시 13.8 g으로 무처리에 비하면 수량 감소율이 유묘기 51%, 분얼기 46%, 최고 분얼기 13%로 일찍 감염될수록 수량 감소 영향이 컷다. 저항성 품종에서는 시기별 감염과 수량 감소가 통계적으로 상관이 없었다. 자연 발병된 농가 포장에서 운광 품종을 대상으로 태안과 진도지역에서 조사한 결과 발병경률 23.4% 이상이면 발병경률의 증가에 따라서 상관계수 0.94로 수량 감소율도 동일하게 증가하였다.

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)
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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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