급성심근경색후 발생한 심실중격결손 2례

김태희,이재호,김애란,허민영,문치숙,정수룡,김대경,김두일,김동수 인제대학교 백병원 2002 仁濟醫學 Vol.23 No.4

Ventricular septal defect remains an infrequent but devastating complication of acute MI. Approximately 1∼3% of cases of acute myocardial infarction are complicated by ventricular septal rupture in the prethrombolytic era and the incidence has decreased to 0.2% with reperfusion therapy. This mechanical complication usually occurs within the first 10 to 14 days when necrotic tissue is most abundant and the collateral coronary circulation is not well developed. This lesion is generally associated with complete coronary obstruction rather than severe stenosis. Rupture of the ventricular septum is a severe mechanical complication of acute myocardial infarction, usually resulting in death unless surgical repair is performed. The bad prognosis of this event within the first 2 weeks indicates the need for early surgical rapair. This complication is more frequent after the first acute myocardial infarction in the elderly and secondary to a transmural myocardial infarction. We report two cases of ventricular septal rupture after acute myocardial infarction.

실리카흄을 흔입한 고강도 콘크리트 개발

홍창우,김태경,김경진,김성환,김남윤,심도식,이정호,윤청호,백민경,원치문,박제선,이주형,정경일 강원대학교 석재복합신소재제품연구센터 1996 석재연 논문집 Vol.1 No.-

콘크리트 구조물이 대형화됨에 따라 설계단면이 증대되어 상대적으로 많은 경제적 손실을 부담하게 된다. 따라서 단면을 감소시키면서도 소요의 하중에 안전한 구조물을 건설하기 위해서는 우선적으로 구조물 건설에 기초가 되는 고품질, 고내구성의 고강도 콘크리트 개발이 절실히 요구된다 본 연구에서는 일정 시멘트비 및 혼화재 비율하에서 소요의 워커빌리티가 확보되는 고강도 콘크리트를 시간과 온도의 변화에 따라 증기 양생하여, 압축, 인장, 휨강도 뿐만 아니라 파괴특성을 실험적으로 연구하였다. 시료 제작시 시멘트 입자 사이의 공극 및 불연속 영역을 충전하여 고밀도화하기 위한 콘크리트용 혼화재로 시멘트 비표면적이 상당히 작은 초미립 분말인 실리카흄을 이용하였다. 또한 AE감수제 및 고성능 유동화제를 사용하여 혼화재의 첨가에 의하여 발생될 수 있는 워커빌리티의 감소를 방지하였다. 실험결과에 의하면 일정 양생 지속 시간하에서 온도의 증가에 따라 콘크리트의 압축, 인장 및 휨강도가 전반적으로 증가하였다. 동일하게 일정 온도하에서 양생 지속시간이 커짐에 따라 강도들이 증가됨을 알 수 있었다. 따라서 상대적으로 높은 온도와 긴 지속 양생 조건하에서 파괴에 대한 저항력이 크게 나타났다. The compressible, tensible, and flexibleresistance of the high strength concrete is analyzed by the experimentation in the present study. For the test, we cure several samples with the silica fume as a mixture being become dense the spaces between the particle of cement under the variation of both the temperature and the curing-interval. Then, the superplasticizer and the ezcon are also used to satisfy the required workability for construction. The compressible, tensible, and flexible resistances to a stress are increased as increasing the temperature and the time interval for the curing. Therefore it is concluded that the overal fractural and mechanical properties is improved by mixing the silica fume into the cement.

오스테나이트系 스테인레스鋼의 熔接 入熱이 殘留應力과 收縮.變形量에 미치는 影響에 관한 硏究

李允景,金治遠 慶南大學校 附設 工業技術硏究所 1992 硏究論文集 Vol.10 No.-

오스테나이트系 스테인레스鋼(STS 304)은 여러가지 長點으로 인해 高級 製品의 素材로 각광을 받고 있는 반면에 또한 一般炭素鋼에 비해 낮은 熱傳導率과 큰 熱膨脹係數 때문에 鎔接施工時에 鎔接入熱에 의해 殘留應力 및 收縮, 變形量의 影響이 크게 나타난다. 이런 鎔接 施工上의 애로를 最少化하기 위해 鎔接入熱에 의해 殘留應力과 收縮 및 變形量에 대해서 검토하였다. Recently, the use of Austenite Stainless Steel has been increasing in wide applications, such as pressure vessels, heat excahngers for chemical plants, and especially component material of nuclear power plants, due to the good characteristics of high anti-corrosion, beautiful external appearance. richful dutility and high heat-resistance. etc. However, many difficulties have been encountered in the field welding and fabrication, because of the large residual stresses and shrinkage-deformations due to the heat-input during welding caused by the very low heattransfer compared with that of general carbon steel. In order to assist for the reduction of these quality problems, this study demonstrates the relationship between residual stresses and shrinkage-deformations caused by the heat-input of several typical welding processes and types of joint for Austenite Stainless Steel(STS304). And, for improving quality and satisfactory welding during field fabrication, the results of this experimental study for minimizing the residual stresses and shrinkage-deformations due to weld heat-input.

냉동 건조 탈회 동종골 이식시 조직 접착제가 골 치유 과정에 미치는 영향에 관한 실험적 연구

민승기,김수남,김치경 大韓顎顔面成形再建外科學會 1995 Maxillofacial Plastic Reconstructive Surgery Vol.17 No.4

Allogeneic bone grafting has recently been used in oral and maxillofacial regions to restore the cosmetic and functional problem. There are several types of allogeneic bone grafts ; bone powder, bone chips, bone blocks. Empirically, it is thought to be better to combine the allogeneic bone chips to any type of tissue adhesive not to displace during packing and condensing. But, there are no reports about using tissue adhesive in allogeneic bone grafting. This experimental study is designed to investigate the effect of the fibrin adhesive on bone healing process after demineralized allogeneic bone grafting in 60 rats. In control groups (30 rats), routine demineralized allogeneic bone grafting were done in 7×7mm calvarial bone defects which were drilled intentioally. And we used the fibrin adhesive for holding the bone particle in experimental groups 930 rats). Each experimental specimen was sacrified at 1, 2, 4, 6, 8 weeks postoperatively The results were as follows : 1. The degree of inflammatory cell infiltrations were more prominent in experimental than in control groups till 2 weeks. 2. Early fibroblast proliferation and new capillary proliferation were uncorporated around graft sites in the experimental groups later than in control groups at early stages. 3. Osteoblastic activity in control group was more prominent at 2 weeks. 4. Osteoblastic activity in experimental groups was more prominent than in control group till 4 weeks. 5. New bone formation was more in control group than experimental group till 3 weeks, but similar appearance after that time. As above results, initial bone healing within 2 weeks were more processed in without adhesive group than with adhesive group. But above 4 weeks; similar bone healing were observed.

첨가질량이 존재하는 변단면 4변고정 적층복합판으 진동해석

박제선,김경진,원치문,심도식 江原大學校 産業技術硏究所 1995 産業技術硏究 Vol.15 No.-

A method of calculating the natural frequency corresponding to the first mode of vibration of beams and tower structures, with irregular cross-sections and with arbitrary boundary conditions was developed and reported by D. H. Kim in 1974. This method has been developed for two-dimensional problems including the laminated composite plates and was proved to be very effective for the plates with arbitrary boundary conditions and irregular sections. In this paper, the result of application of this method to the clamped composite plates with non-uniform cross-section and with attached point mass/masses is presented.

축하중과 첨가질량이 작용하는 적층복합판의 진동해석

이봉학,김경진,원치문,성기태 江原大學校 産業技術硏究所 1995 産業技術硏究 Vol.15 No.-

A method of calculating the natural frequency corresponding to the first mode of vibration of beams and tower structures, with irregular cross-sections and with arbitrary boundary conditions was developed and reported by D. H. Kim in 1974. IN this paper, hte result of application of this method to the laminated plates with axial forces and with attached point mass/masses is presented. Both N? and N? forces are considered. The solution for the laminated plates with arbitrary boundary conditions and irregular section can be obtained by simply obtaining the deflection influence coefficients by any method. The effect of neglecting the mass of the plates on the natural frequency, as the ratio of the point mass/masses to the plate mass increases, is thoroughly studied. The influence of N? and N? is also carefully investigated.

복합구조물의 파괴에 관한 치수효과의 중요성

정영화,김경진,원치문,심도식 江原大學校 産業技術硏究所 1995 産業技術硏究 Vol.15 No.-

In this paper, the importance of the size effects on the strength ratio is demonstrated by numerical results. The rate of decrease of tensile strength is for glass fiber, based on the experience of a composite manufacturing specialist. For other material, similar procedure may be used until detailed test result on such material is available. The strength criteria used is that of Tsai-Wu for stress space. The factors influencing the ratio are, reducing the tensile strength alone or both tensile and compression strengths, selection of the normalized interaction term, that is, the generalized Von Mises criterion or the Hill's criterion, and the status of applied stresses. Some of the numerical results are presented for a guideline for the furture study.

EGR 및 터보과급이 디젤기관의 성능특성에 미치는 효과에 관한 실험적 연구

윤창식,이윤경,김치원 慶南大學校 附設 工業技術硏究所 1997 硏究論文集 Vol.14 No.2

압축점화기관은 높은 열효율, 내구성, 신뢰성 및 고출력을 요구한다. 하지만, 디젤기관은 가솔린기관에 비해서 보다 많은 양의 오염물질을 방출해 왔다. 본 실험적연구에서는, 기관성능, 연소특성 및 배기배출물을 터보과급기를 사용한 경우와 사용하지 않고 실험을 하였고, 기관운전변수로는 EGR과 기관회전수에 대해서 실험을 행하여 비교분석함으로써 성능향상을 위한 최적의 기관운전조건을 규명하였다. Mostly, the CI engines are demanded due to high thermal efficiency, endurance, reliablity and power. However, since a Diesel engine emits more amount of pollution than a Gasoline engine dies. In this experimantal study, engine performance, combustion charactristics and exhaust emission were tested with and without turbocharger, and then, the tested parameters were EGR and engine speed.

한국인 정신분열병 환자의 지연성 운동장애와 $CYP2D6^*4$ 및 $CYP2D6^*10$ 다형성들의 연합에 대한 고찰

우성일,강동우,서한길,김봉조,이인상,정근화,박소영,정치영,이환철,정경천,손진욱,Woo, Sung-Il,Kang, Dong-Woo,Seo, Han-Gil,Kim, Bong-Jo,Lee, In-Sang,Jeong, Geun-Hoa,Park, So-Young,Jung, Chi-Yeong,Lee, Hwan-Cheol,Jeong, Kyeong-Cheon,Sohn, 대한생물정신의학회 2000 생물정신의학 Vol.7 No.2

P450 CYP2D6 enzyme(=debrisoquine hydroxylase) is known to metabolize many neuroleptics and some genetic polymorphisms in the CYP2D6 gene were reported to be associated with tardive dyskinesia(TD). We investigeted the association of two genetic polymorphisms in the CYP2D6 gene, $CYP2D6^*4$ and $CYP2D6^*10$, with TD in Korean schizophrenic subjects. Subjects consisted of 71 Korean schizophrenics and TD was evaluated using the Abnormal Involuntary Movement Scale (AIMS). There were no statistically significant differences in the demographic variables of age, male to female percentage and the current antipsychotic(CPZ equivalent) dose between the group with TD and the group without TD. But the duration of antipsychotic drug exposure was significantly higher in the group without TD(p=0.000, by independent t-test). The mean AIMS score in the group with TD was $11.2{\pm}6.6$(S.D.). Genotypings for the presence of $CYP2D6^*4$ and $CYP2D6^*10$ were done using PCR amplifications and endonuclease digestions. There were no statistically significant genotypic and alleleic associations between TD and $CYP2D6^*4$(by chisquare tests), and between TD and $CYP2D6^*10$(by chi-square tests). These results indicate that the $CYP2D6^*4$ and $CYP2D6^*10$ polymorphisms have no significant roles in the causation of TD.

Efficient isolation of sperm with high DNA integrity and stable chromatin packaging by a combination of density-gradient centrifugation and magnetic-activated cell sorting

Chi, Hee-Jun,Kwak, Su-Jin,Kim, Seok-Gi,Kim, Youn-Young,Park, Ji-Young,Yoo, Chang-Seok,Park, Il-Hae,Sun, Hong-Gil,Kim, Jae-Won,Lee, Kyeong-Ho The Korean Society for Reproductive Medicine 2016 Clinical and Experimental Reproductive Medicine Vol.43 No.4

Objective: This study was carried out to investigate the correlations of the sperm DNA fragmentation index (DFI) with semen parameters and apoptosis, and to investigate the effects of density-gradient centrifugation (DGC) and magnetic-activated cell sorting (MACS) on reducing the proportion of sperm with DNA fragmentation and protamine deficiency. Methods: Semen analysis and a sperm DNA fragmentation assay were performed to assess the correlations between semen parameters and the DFI in 458 semen samples. Sperm with progressive motility or non-apoptosis were isolated by DGC or MACS, respectively, in 29 normozoospermic semen samples. The effects of DGC or MACS alone and of DGC and MACS combined on reducing the amount of sperm in the sample with DNA fragmentation and protamine deficiency were investigated. Results: The sperm DFI showed a significant correlation (r=-0.347, p< 0.001) with sperm motility and morphology (r=-0.114, p< 0.05) but not with other semen parameters. The DFI ($11.5%{\pm}2.0%$) of semen samples was significantly reduced by DGC ($8.1%{\pm}4.1%$) or MACS alone ($7.4%{\pm}3.9%$) (p< 0.05). The DFI was significantly further reduced by a combination of DGC and MACS ($4.1%{\pm}1.3%$, p< 0.05). Moreover, the combination of DGC and MACS ($1.6%{\pm}1.1%$, p< 0.05) significantly reduced the protamine deficiency rate of semen samples compared to DGC ($4.4%{\pm}3.2%$) or MACS alone ($3.4%{\pm}2.2%$). Conclusion: The combination of DGC and MACS may be an effective method to isolate high-quality sperm with progressive motility, non-apoptosis, high DNA integrity, and low protamine deficiency in clinical use.