• 제목/요약/키워드: Failure detection

검색결과 850건 처리시간 0.033초

조직판막을 이용한 승모판 치환술의 중기 성적 (Midterm Results of the Bioprosthesis in Mitral Position)

  • 조현진;이재원;정성호;제형곤;주석중;송현;정철현
    • Journal of Chest Surgery
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    • 제41권6호
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    • pp.695-702
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    • 2008
  • 배경: 심장 판막 수술에서 조직판막 혹은 기계판막의 선택은 중요한 문제이고, 조직판막의 내구성이 그 결정에 주요한 역할을 한다. 본 연구는 승모판에서 조직판막 이식 후 중기 결과를 알아보고자 하였다. 대상 및 방법: 1989년 7월부터 2007년 8월까지 조직판막을 이용하여 승모판 치환술을 받은 모든 환자를 대상으로 하였다. 216명의 환자에서 236예의 수술을 시행하였으며 평균 연령은 $63{\pm}15$세, 남녀 비는 1 : 3이었다. 술 후 총 추적 관찰 기간은 760.2 patient-years, 평균 추적 관찰 기간은 $41.9{\pm}40.7$개월 ($0{\sim}212$개월)이었고, 외래 경과 기록과 의무 기록을 통해 후향적으로 분석하였다. 결과: 조기 사망은 18명(8.3%)이었고, 13명은 승모판 치환술과 다른 동반 수술을 같이 시행한 경우였다. 5년, 8년에서 생존율은 각각 $79.9{\pm}3.5%$, $65.5{\pm}5.5%$이었으며, 구조적 판막 손상으로부터의 5년, 8년 회피율(freedom from structural valve deterioration, SVD)은 각각 $96.2{\pm}2.2%$, $85.9{\pm}5.3%$이었다. 재수술의 5년, 8년 회피율(freedom from Reoperation)은 $96.0{\pm}1.7%$$, $90.4{\pm}4.2%$, 구조적 판막 손상으로 인한 재수술의 회피율(freedom from Reoperation for, SVD)은 $98.1{\pm}1.2%$$, $92.3{\pm}4.1%$이었다. 수술 전 위험인자의 다변량 분석에서 작은 판막(Valve size 25 and 27 mm)을 사용한 경우가 재수술의 유의한 위험 인자였으며, 중등도 이상의 좌심실 기능부전(Left ventricle ejection fraction, LVEF < 40%)은 구조적 판막 손상과 사망률의 유의한 위험인자였다. 결론: 승모판의 조직판막 치환술에서 생존율과 재수술의 회피율은 만족할 만한 중기 성적을 보여주나, 구조적 판막 손상의 회피율은 비교적 낮은 성적을 보였다. 수술 후 8년을 전후해서 급격한 손상의 진행을 보이므로, 8년을 기준으로 해서 잦은 경과 관찰과 심초음파 검사는 판막 손상의 조기 발견에 도움이 될 것이며, 더 많은 환자 수에서 보다 장기적인 연구가 필요할 것이다.

초기 동맥혈 Carboxyhemoglobin 농도가 높았던 화상 환자들의 예후지표에 관한 연구 (The Early Prognosis of Burn Patients with Elevated Initial Arterial Carboxyhemoglobin Level)

  • 최창순;김철홍;김근숙;이태유;정연손;엄광석;박용범;장승훈;김동규;박명재;이명구;현인규;정기석;김종현
    • Tuberculosis and Respiratory Diseases
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    • 제55권2호
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    • pp.188-197
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    • 2003
  • 연구배경 : 고열과 유독가스에 의한 흡입 폐 손상은 화상 환자에서 화재와 관련한 주된 사망원인이다. 따라서 조기진단과 적절한 치료가 중요한데, 본 연구는 초기 COHb 농도가 증가한 화상 환자의 임상 특성 및 경과를 관찰하고 흡입 폐 손상에 대한 예후인자를 알아보고자 하였다. 방 법 : 2001년 8월부터 2002년 7월까지 응급실 통해 내원한 1,416명 환자 중 동맥혈 가스검사에서 COHb 농도가 5% 이상인 39명을 사망군(12명)과 생존군(27명)으로 나누어, 임상특성, 임상적 흡입 손상 정도, 흉부 X-선 소견, 화상 체표 면적, APACHE II 점수, SAPS II 점수 등을 후향적으로 비교하였다. 결 과 : 생존군과 사망군 사이에 COHb 농도는 각각 $10.3{\pm}8.8%$, $9.7{\pm}5.7%$, 화상 체표면적은 $16.6{\pm}17.8%$, $60.7{\pm}28.8%$였다. 임상적 흡입 폐 손상 정도 및 초기 흉부 X-선 소견은 생존군과 사망군 사이에 유의한 차이점을 관찰할 수 없었다. 두 군사이의 사망관련 인자로는 화상 체표면적, APACHE II 점수, SAPS II 점수, 기계 호흡 및 총 입원기간이 관여하고 있었으나 다변량 분석에서 화상 체표 면적이 가장 중요한 사망관련 인자였다. 결 론 : 초기 동맥혈 COHb 농도가 증가되어 있는 화상환자의 예후는 불량할 것으로 기대되기 때문에 치료에 많은 관심을 기울여야 할 것으로 사료된다. 하지만, COHb이 흡입 폐 손상을 동반한 화상 환자의 예후에 미치는 효과에 대해서는 향후 전향적 연구를 통해서 검토되어져야 할 것으로 생각된다.

일측성 신발생이상 환아에 동반된 반대측 방광요관역류 (Contralateral Vesicoureteral Reflux in Children with Abnormal Unilateral Renal Development)

  • 오성욱;이재승;김명준;한상원;배기수
    • Childhood Kidney Diseases
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    • 제1권1호
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    • pp.53-59
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    • 1997
  • 목적 : 한쪽 신장이 완전히 기능이 없는 무형성신이나 거의 기능이 없는 다낭성이형성신 환아에서 하나 남은 신장마저 방광요관역류가 동반되어 손상되는 사례가 최근 많이 보고되고 있어 일측성 무형성신, 저형성신, 다낭성이형성신을 일측성 신발생 이상이라는 하나의 군으로 묶어 일측성 신발생 이상 반대측으로 방광요관역류가 잘 동반되는지를 조사하고자 하였다. 방법 : 1987년 1월 1일부터 1996년 12월 31일까지 세브란스 병원, 영동 세브란스 병원에서, 또 1994년 1월1일부터 1996년 12월 31일까지 아주대학 병원에서 일측성 무형성신, 저형성신, 다낭성이형성신으로 진단받은 96명의 소아를 대상으로 후향적 연구를 시행하였다. 진단은 방사선 소견에 근거하였으며, 96명의 대상 환아 중 48명의 환아가 배뇨성 방광요도조영술을 시행하였다. 결과 : 1. 일측성 신발생 이상을 가진 96명 환아군의 성별 분포는 남아가 58명으로 60%였고, 여아가 38명으로 40%였다. 2. 일측성 신발생 이상의 분포는 좌측이 45례로 47%였고, 우측이 51례로 53%였다. 3. 일측성 신발생 이상을 진단받게 된 동기를 보면 총 96례 중 산전 진단에 의한 경우가 41례로 가장 많았으며, 요로 감염의 검사 도중이나 다른 동반 기형의 평가 도중 발견된 경우가 각각 18례, 16례로 많았다. 질환별로 볼 때 일측성 무형성신이나 저형성신은 요로 감염의 검사 도중이나 다른 동반 기형의 평가 도중 발견된 경우가 많았으나 다낭성이형성신은 산전 진단으로 발견된 경우가 대부분이었다. 4. 배뇨성 방광요도조영술을 시행한 환아들의 경우 일측성 신발생 이상의 진단 연령은 $1.8{\pm}3.3$세였고, 배뇨성방광요도 조영술의 시행 연령은 $2.5{\pm}3.8$세로 통계적으로 유의한 격차가 있었다(P<0.01). 5. 일측성 무형성신으로 진단받은 18명의 환아 중 9명, 일측성 저형성신으로 진단받은 11명의 환아 중 5명, 일측성 다낭성이형성신으로 진단받은 19명의 환아 중 3명에서 반대측 방광요관역류가 있었다. 6. 방광요관역류가 있었던 환아들은 역류의 정도가 평균 3등급 이상으로 중등도 이상이었다. 반대측 방광요관역류가 있었던 17명의 환아 중 3명은 만성 신부전 상태에 있었고, 6명은 방광요관문합술을 시행받았다. 결론 :한쪽 신장의 기능이 없거나 거의 없다고 여겨지는 일측성 신발생 이상 환아에서 반대측 방광요관역류를 조기에 발견하기위해 선별적 검사로 배뇨성 방광요도조영술을 반드시 시행해야 한다고 결론지을 수 있었다.

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반복 집단 치료에 의한 간흡충증의 관리 및 진단에서 초음파검사의 저효용성 (Control of clonorchiasis by repeated praziquantel treatment and low diagnostic efficacy of sonography)

  • Sung-Tae HONG;Kisung YOON;Mejeong LEE;Min SEO;Min-Ho CHOI;Jung Suk SIM;Byung Ihn CHOI;Chong Ku YUN;Soon-Hyung LEE
    • Parasites, Hosts and Diseases
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    • 제36권4호
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    • pp.249-254
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    • 1998
  • 간흡충은 현재 국내에서 가장 충란양성률이 높은 인체기생충으로 우수한 구충효과를 보이는 국산 프라지콴텔이 사용되고 있음에도 여전히 유행도가 높아 관리대책이 필요하다. 이 연구는 간흡충이 유행하는 한 마을에서 충란양성자를 6개월 간격으로 반복 검사 및 투약하면서 관리효과를 파악하고 간흡충증의 진단에서 복부초음파검사의 유용성을 검토하였다. 충북 괴산군의 한 마을에서 충란양성률이 처음 22.7%이었으나, 치료를 반복하면서 6개월 후에 19.6%, 12개월 후에 15.1%, 18개월 후에 12.2%, 24개월 후에 6.3%, 30개월 후에 11.4%, 42개월 후에 6.3%를 나타내었다. 한 번 이상 초음파 검사와 검변에 참여한 피검사자 총 123명 중에서 61명 (49.6%) 이 간내 담관이 관찰되어 양성소견을 보였으나, 이들 중에서 충란양성률은 18.7% (23/123)이었다. 충란양성자 중에서 52.5%, 충란음성자 중에서 49%가 초음파 양성소견을 보여 충란양성 여부와 초음파 양성소견은 관련성이 없었다. 또한 치료 후에 초음파로 검사한 결과 치료 후 6개월 64.3%, 12개월 50%, 18개월 50%, 24개월 66.7%의 초음파 양성소견을 보였다. 비유행지에서 주민 64명의 충란음성자를 대상으로 초음파로 검사한 결과 20 (31.3%)명이 양성으로 관찰되었다. 이 연구의 결과에 의하면 6개월 간격으로 충란양성자를 3년 6개월간 지속적으로 투약하여도 간흡충증의 집단관리가 충분하지 못하며, 초음파검사는 유용성이 낮은 진단법임을 확인하였다.

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원발성 폐암의 외과적 치료 (Surgical Treatment of Primary Lung Cancer)

  • 김성완;구본원;이응배;전상훈;장봉현;이종태;김규태;강덕식
    • Journal of Chest Surgery
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    • 제31권2호
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    • pp.134-141
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    • 1998
  • 최근 원발성 폐암의 유병률이 점점 증가하고 있으며, 비소세포폐암의 완치 목적의 치료로 외과적 폐절제술이 가장 좋은 방법으로 알려져있다. 저자들은 1992년 1월부터 1995년 7월까지 경북대학교병원 흉부외과에서 원발성 비소세포폐암으로 폐 절제술을 받은 환자중 100례의 임상기록을 분석하여 다음과 같은 결과를 얻었다. 남자가 86례, 여자가 14례로 남녀비는 6 : 1이었고, 60대가 43%로 환자의 대부분을 차지하였고 최소 34세 및 최고 81세였다. 수술수기는 단엽절제술 55례(55%), 전폐절제술 22(22%), 쌍엽절제술 15례(15%), 구역절제술 2례(2%) 및 기관지성형술이 필요했던 수상엽절제술, 수상전폐절제술 및 쐐기전폐절제술이 각각 4례, 1례 및 1례였다. 수술후 조직학적 분류는 편평상피세포암 67례(67%), 선암 26례(26%), 거대세포암 6례(6%) 및 선평편상피세포암 1례(1%)였다. 종격림프절로 전이가 있었던 예는 총 18례(18%)였으며, 편평상피세포암이 8/67(11.9%)례, 선암이 9/26(34.6%)례, 거대세포암이 1/6(16.7%)례였다. 술후 병리학적 병기는 1병기 45례(45%), 2병기 13례(13%), 3a병기 36례(36%), 3b병기 5례(5%) 및 4병기 1례(1%)였다. 전체 환자에서의 12개월, 24개월, 36개월 및 43개월의 생명표법에의한 생존률은 각각 77.5%, 56.1%, 43.7% 및 43.7%였으며, 병기별 43개월의 생존률은 1병기에서 81.3%, 2병기에서 20.8%, 3a병기에서 27.9%, 3b병기에서 25.0%였다. 수술후 병원사망은 패혈증 2례, 호흡부전 1례 및 급성 심경색에 의한 급사가 1례로 총 4례(4%)였다. 원발성폐암의 절제술후 생존률을 향상시키기 위해서는 조기 발견 및 수술적응 환자의 적극적인 수술이 필요한 것으로 판단되었다.Hg로 감소하였고 폐동맥압의 평균은 수술전에 11.4$\pm$5.68 mmHg에서 25.94$\pm$11.53, 29.67$\pm$9.31 mmHg로 증가 하였으나 모두 통계적 의의는 없었다(p>0.05). 양측 폐이식수술에서인 폐동정맥문합부위의 파열, 협착, 뒤틀림 등의 수술수기상의 문제점을 예방하면서 우측폐를 먼저 이식하면서, 폐수술시야를 충분히 확보하고, 재관류손상을 방지하는 경우 cystic fibrosis, pulmonary hypertention, emphysema와 같은 심한 호흡부전증 환자의 치료방법으로 적합하리라 사료된다.에서 선택수술 (elective coronary artery bypass graft)에 비하여 특별한 위험 요소의 증가 관상 동맥 우회술을 적용하여 좋은 결과를 얻을 수 있었으며 이들에 대한 장기 추적이 릴요할 된다.착군에 비하여 의미있게 작았는데 이는 아마도수술 당시 협 착 부위의 완전제거가 이루어지지 않은 것이 원인이라고 사료되었다. 본 분석에서는 어린 연령(3개월 이하), 3개월이하에 시행한 쇄골하동맥편 교약성형술이 의미있는 재협착의 위험요소로 밝혀졌다. 결론 적으로 저자등은 본연구를 통하여 대동맥협부지수, 횡대동맥 지수 등이 개개 대동맥교약 환아의 해부학 적, 임상적 특징을 파악하는데 도움이 되는 도구라는 사실을 발견하였고 아울러 교약의 해부학적 특성, 동반 심기 형, 연령, 수술방법 등이 수술사망 및 재협착에 영향한다는 사실을 입증하였다.t was resulted from increase of weight of single cocoon. "Manta"2.5ppm produced 22.2kg of cocoon. It is equal to 9% increase in index, as compared to that of control. In case

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우연히 발견된 무증상 구루병 8예 (Eight cases of incidentally diagnosed as subclinical rickets)

  • 서지영;김규리;이희우;안영민
    • Clinical and Experimental Pediatrics
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    • 제51권8호
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    • pp.812-819
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    • 2008
  • 목 적 : 비타민 D는 뼈의 무기질화에 필수적인 역할을 하는 호르몬으로 부족하게 되면 구루병이 생길 수 있다. 본 연구는 비타민 D 결핍증이 잘 발생하는 위험군을 알아보고 그 예방 대책에 대한 관심을 고지하고자 계획하게 되었다. 방 법 : 2003년 3월부터 2007년 7월까지 노원을지병원 소아과에 내원한 환아들중에서 검사 상 우연히 알칼리성인산분해효소가 증가해 있으면서 방사선사진으로 무증상 구루병으로 진단받은 환아들에 대하여 후향적으로 그 특징과 치료 경과를 조사하였다. 결 과 : 남아 6명과 여아 2명의 총 8명이 무증상 구루병으로 진단되었다. 이들의 진단 시 연령은 $12.6{\pm}5.8$개월이었으며, 1월부터 7월 사이에 진단되었고 동반질환으로 폐렴, 요로감염, 장염, 철결핍성 빈혈이 있었다. 이들은 모두 모유 수유를 위주로 하고 있었고, 진단당시 2명의 환아가 몸무게가 3백분위수 미만으로 성장 장애를 보이고 있었다. 진단 시 평균 혈중 알칼리성인산분해효소는 $1,995.8{\pm}739.5IU/L$로 증가되어 있었고, 평균 혈중 칼슘은 $9.5{\pm}0.6mg/dL$, 평균 혈중 인은 $3.6{\pm}1.5mg/dL$였다. 평균 intact-PTH는 $214.8{\pm}155.9pg/mL$로 증가되어 있었고 25-hydroxyvitamin D는 2명을 제외한 6명의 환아에서 30 ng/mL 미만으로 감소되어 있었다. 모든 환자들은 손목 방사선 촬영에서 구루병양 변화를 보이고 있었으나 외관상 골기형이나 발달 장애는 없었다. 이들 중 6명은 3개월간 calcitriol을 투여한 후 생화학적인 검사와 손목 방사선 사진 상의 변화는 호전되었고 정상적으로 성장하였다. 2명은 치료하지 않은 채 저절로 호전되었으며 역시 외관상 성장장애를 보이지는 않았으나 2년간의 추적 관찰 후 현재 1명은 무릎 관절면의 골간단 이형성을 보이고 있으며 다른 1명은 일시적인 척추 측만증을 보였다가 호전되고 있다. 결 론 :무증상 구루병으로 진단된 환아들이 비타민 D 결핍이나 부족으로 인한 것으로 생각되며 모유 수유아에서 비타민 D 결핍증의 빈도가 높으므로 알칼리성인산분해효소가 높은 환자에서는 이를 의심하여 25-hydroxyvitamin D와 손목 방사선 사진을 검사하여 확인하여야 하며 이들 중 일부는 비타민 D 결핍성 구루병으로 진행할 수 있으므로, 모유 수유아에서 비타민 D 보충에 대한 교육이 필요하리라 생각된다.

선천성 방광요관역류 환아의 형제자매에서 방광요관역류와 신반흔의 유병률 (Incidence of Vesicoureteral Reflux and Renal Scar in Asymptomatic Siblings of Patients with Primary Vesicoureteral Reflux)

  • 유재은;석효정;송준영;박문성;김영수;배기수
    • Childhood Kidney Diseases
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    • 제7권2호
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    • pp.181-188
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    • 2003
  • 목적 : 방광요관역류는 역류성 신병증의 주된 원인으로 작용하여 소아기 고혈압과 신부전을 유발하는 주요 원인으로 기여한다. 방광요관역류는 가족적 발생경향이 있어, 고위험군인 환자의 형제자매를 대상으로한 역류 선별검사의 시행이 국외에서는 보편적이나 국내에서는 아직 연구보고가 적어 그 시행이 제한되고 있다. 본 연구에서는 방광요관역류 환아의 형제자매에서 역류와 신손상의 유병률을 조사하여 형제자매 선별검사의 의의를 살피고자 하였다. 또한 지표환자의 임상경과를 분석하여 형제자매의 유병률에 영향을 미치는 요인이 있는지를 살펴보았다. 방법 : 1994년 6월부터 2001년 5월까지 아주대학교 병원 소아과에서 일차성 방광요관역류로 진단받은 지표환아 37명과 그들의 형제자매 50명을 대상으로 임상양상을 조사하고 배뇨 중 방광 요도조영검사, $^{99m}Tc-DMSA$ 신주사 검사, 요화학 및 요배양 검사를 시행하였다. 결과 : 지표환자 37명은 평균 $3.35{\pm}1.13$등급의 역류상태를 나타냈고 이들 중 59.5%에서는 신주사 검사상 신피질 결손을 보였다. 지표환자의 형제자매 50명 중 8명(16%)에서 방광요관역류가 있었고, 이들 중 7명(87.5%)에서는 신피질 결손을 보였으며 2명은 비가역적인 신반흔이 있었다. 역류가 없이 신피질 결손이 있는 경우도 1례 있었다. 형제자매의 방광요관역류 존재를 예측할만한 지표환자의 임상적 요인은 없었다. 결론 : 선별검사로 발견된 방광요관역류 환아의 형제자매에서 방광요관역류와 신피질손상의 유병률은 각각 16.0%, 16.0%로 형제자매가 '신손상의 고위험군'에 속함을 알 수 있었다. 따라서 방광요관역류 환아를 진료할 때, 그들의 형제자매에 대한 선별검사를 추천 시행하는 것이 가능한 신손상을 예방할 수 있는 효과적인 방법이라 판단된다. 또한 형제자매 선별검사를 할 때, 과거 시점의 역류로 인하여 형성된 신손상의 존재도 밝혀내기 위하여, 배뇨 중 방광요도조영 검사뿐만이 아니라 신주사 동위원소 검사도 포함시켜야 함을 주장하는 바이다.

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대량 모근 시료 DNA 분리 체계 확립과 11 microsatellite maker를 사용하는 한우 생산이력제로의 적용가능성 검증 (Establishment of the High-Throughput Hair Roots' DNA Isolation System and Verification of Its Appicability for Hanwoo Traceability Using the 11 Microsatellite Makes)

  • 임현태;이상호;유채경;선두원;조인철;윤두학;양대용;정일정;이정규;전진태
    • 농업생명과학연구
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    • 제44권6호
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    • pp.91-99
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    • 2010
  • 한우 이력추적제에 적용되는 11개의 MS marker (TGLA227, BM2113, TGLA53, ETH10, SPS115, TGLA126, TGLA122, ETH3, ETH225, BM1824 and INRA23)와 성감별을 위한 2개의 sexing primer로 조합된 하나의 Multiplex PCR set를 이용하여 모근에서 추출한 genomic DNA를 이용해 3510두의 대량 시료를 분석한 결과 3.93%의 genotyping 실패율로 성공적인 분석결과를 얻었다. 무작위교배집단으로 가정 시 동일개체출현확률 (PI)은 $1.31{\times}10^{-23}$, 반형매교배집단으로 가정 시 동일개체출현확률 ($PI_{half-sibs}$)은 $2.52{\times}10^{-16}$ 그리고 전형매교배집단으로 가정 시 동일개체출현확률 ($PI_{sibs}$)은 $1.09{\times}10^{-6}$으로 나타나 현재 사용 중인 11종의 MS marker는 범용적으로 사용하여도 무방할 것으로 재확인 되었다. 또한 생산 및 사육단계의 생우의 경우 모근을 이용하여 DNA를 추출하는 것은 시료 채취 시 소에게 주어지는 스트레스를 최소화 시킬 수 있을 뿐만 아니라 대립유전자형 분석에 있어서 시간적, 경제적인 효율성을 높일 수 있었다. 또한 모근 채취 부위 중 등, 배, 꼬리상부와 꼬리하부를 이용하여 검정한 결과 꼬리하부의 모근을 이용하여 5~13가닥을 사용했을 때 최적의 분석결과를 보였다. 최종적으로 한우의 사육단계 대량 유전자형 분석에 적용 가능한 96 well 단위를 기본으로 하는 모근 DNA분리 체계를 확립하였다.

Sensory Information Processing

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

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

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

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