Glow放電法에 의한 α-Si蒸着裝置의 製作과 그 試料의 特性

유동선,현옥배,고년규,황정남,정원모,이철주 연세대학교 자연과학연구소 1981 學術論文集 Vol.7 No.-

Glow방전법에 의해서 SiH_4를 분해하여 α-Si 박막을 얻을수 있는 장치를 제작하였다. 이 SiH_4기체는 수소기체속에서 10%로 희석되였으며, 진공방전함속에서 rf 전압에 의하여 분해된 Si는 유리기판위에 증착된다. α-Si박막은 1~1.6 A˚/sec의 증착율로 약 7000 A˚의 두께까지 증착되였다. α-Si 박막의 흡수계수는, 2.3 eV의 photon energy 영역에서 약 10^4 cm^-1이고, 그 optical gap은 약 2.1 eV였다. 이 박막의 증착율은 전극간격에 따라 변하고 있으나, 최적전극간격과 기체유입량은 각각 2.6cm와 1~2cc/min였다. Apparatus capable of producing α-Si film by the glow discharge method was designed and constructed in this study. The monosilane gas which is diluted in H_2 gas to 10% is decomposed in the reaction chamber by rf oscillation. The apparatus is composed of a reaction chamber, a rf generator, a cooling system, etc. The α-Si thin film is produced at a deposition rate of 1~1.6 A˚/sec to a thickness of about 7000 A˚. Its absorption coefficient is about 10^4 cm^-1 in the photon energy region of ~2.3 eV, and its optical gap is about 2.1 eV. The deposition rate for the film is controlled by varying the distance between electrode and substrate. The optimum distance and gas flow is about 2.6 cm and 1~2 cc/min, respectively.

마이크로그로브 형태에 따른 평활근 세포 운동 측정

유소영,박찬영,정석,김동익,이병붕,허세호,한동철,장준근 대한혈관외과학회 2002 Vascular Specialist International Vol.18 No.2

Purpose: The spreading, orientation, and chemotaxis the gradient of a chemoattractant of smooth muscle cells (SMCs) were studied on the micro-grooved substrata by the light, fluorescence and scanning electron microscopy. Method: Vertical-walled grooves were produced in silicon wafers by the micromachining technique. All grooves were 4~20㎛ deep and 10~80㎛ wide, SMCs were cultured on each microgroove and examined under stereo-microscope. Result: Cell clusters were markedly oriented by all the grooved substrata examined. Tim-lapse images acquired from CCD (Charge Coupled Device) showed that the grooves directed the migration of SMCs. There was no prominent difference in the migration speed of SMCs according to the grooves. All the cytoskeletal fibers were reoragnized in the same direction with grooves. Especially the alignments of microtubule and intermediate filaments were distinguished in the SMCs on the micro grooves. Conclusion: These results could be applied to the analysis of vascular restenosis and the development of artificial blood vessels.

Cyclosporine과 Ketoconazole의 약물상호작용을 이용한 아토피 피부염 치험 2예

김동원,표형찬,은희철,이유신 大韓臨床藥理學會 1993 臨床藥理學會誌 Vol.1 No.1

Cis-Dichlorodiammineplatinum이 Mouse 간장의 인산염 분해효소활성에 미치는 영향

유신철,이동준,정호삼,이규식 漢陽大學校環境科學硏究所 1987 環境科學論文集 Vol.8 No.-

cis-Dichlorodiammineplatium(Ⅱ)(cis-DDP)은 최근에 개발된 효과적인 종양화합 요법제인 금속화합물로서 그 작용기작은 아직 불명하나 bifunctional alkylating agent와 유사한 작용 기전을 갖는 것으로 알려져 있다. cis-DDP는 체내에서 가수분해되어 DNA와 반응함을 핵산의 합성을 억제하여 암세포 뿐만 아니라 정상세포에도 영향을 미쳐 출혈성장염, 임파조직과 골수의 저세포증, 신손상, 단백뇨 및 혈뇨등의 부작용을 유발한다. 이에 저자는 cis-DDP가 mouse 간장에서 세포독성으로 작용하여 간실질세포의 변성을 일으키리라 사료되어 간실질세포내의 acid phosphatase, alkaline phosphstase 및 aden-osine triphosphatase의 변동을 조직화학적으로 관찰하였다. 실험동물은 DDY계의 웅성(체중 20g)mouse를 사용하였으며 체중 kg당 6mg의 cis-DDP를 투여한 후, 6시간, 12시간, 24시간 및 48시간 경과후에 희생하여 간조직을 적출하고 10% formalin용액에 고정하고 cryostat로 16㎛두께로 동결절편을 만들었다. 조직화학적인 연구를 위하여 acid phosphatase와 alkaline phosphatase의 활성은 Gomori 방법으로 그리고 adenosine triphosphatase의 활성은 Wachstein-Meisel 방법으로 이들 효소활성을 관찰하여 다음과 같은 결과를 얻었다. 1. Acid phosphatase 활성은 간소엽주변대에서 cis-DDP투여 6시간 경과군의 mouse에서는 약한 양성반응을 12시간 경과군의 mouse에서는 중등도의 양성반응을 48시간 경과군의 mouse에서는 약한 양성반응을 나타내었다. 2. Alkaline phosphatase 활성은 간소엽 주변대에서 cis-DDP투여 12시간, 24시간, 및 48시간 경과군의 mouse에서 중등도의 양성반응을 나타내었다. 3. Adenosine erihosphatase 활성은 간소엽 중심대에서 cis-DDP투여 6시간 경과군의 mouse에서 미약한 양성반응을 나타내었고, 12시간 경과군의 mouse에서는 중등도의 양성반응을 나타내었고, 24시간 및 48시간 경과군의 mouse에서는 각각 중등도 및 강한 양성반응을 나타내었다. 이상의 소견을 종합한바 cis-DDP의 투여로 mouse의 간장 손상을 일으켜 acid phosphstase, alkaline phospatase 및 adenosine triphosphatase 활성은 일시적으로 저하되었다가 회복되는 것으로 사료된다. cis-Dichlorodiammineplatinnm(Ⅱ) (cis-DDP), known as cisplatin, is a metallic compound that has recently been developed as an effective cancer chemotherapeutic agent. The precise mechanism of action of cis-DDP is still unknown. Similarities between the mechanism of action of this drug and bifunctional alkylating agents have been suggested. Upon entering the cell, the platinum compounds will become hydrolyzed, and then they can react with DNA. They act on tumor cells as well as normal cells. Side effects included severe hemorrhagic enterocolitis, severe hypocellularity of the bone marrow and lymphoid tissues, renal lesions, proteinuria and (microscopic henaturia). In this experiment, the author studied the effect of cis-DDP on the mouse liver, histochemically observing the changes in the activities of acid phosphatase, alkaline phosphatase, and adenosine triphosphatase. Male mice (the weight 20g), DDY strain, were used as experimental animals. The experimental animals were sacrificed at 6,12,24 and 48 hours after administration of 6mg of cis-DDP per kilogram of body weight. The specimens obtained from the liver were fixed in 10% formalin solution and sliced at 16㎛ thickness in a frozen cryostat. The activities of acid and alkaline phosphatases were observed by the Gomori's method and the activity of adenosine triphosphatase was observed by the Wachstein Meisel's method for histochemical study. The results are as follows. 1. The acid phosphatase activity was weakly positive at 6 hours and moderately positive at 12 hours and weakly positive at 48 hours after administration in the peripheral zone of the hepatic lobule. 2. The alkaline phosphatase activity was decreased to moderately positive at 12,24 and 48 hours after administration in the peripheral zone of the hepatic lobule. 3. The adenosine triphosphatase activity was trace positive at 6 hours after administration in the central zone of the hepatic lobule and moderately positive at 12 hours after admnistration in the central and peripheral zone of the hepatic lobule. It is suggested that cis-DDP causes changes in activities of acid phosphatase, alkaline phosphatase and adenosine triphophsatase in the liver, due probably to the cytotoxic effect in the parenchymal cells of the liver in mice.

수종의 유기용제가 사람 정자의 점액 침투능, 운동성과 생존율에 미치는 영향

유동철,최달웅 한국환경독성학회 2004 환경독성보건학회지 Vol.19 No.2

Alcohol consumption and exposure to endocrine disruptors and industrial solvents have been implicated in impaired spermatogenesis, increase in the incidence of malformed sperm and decrease in the percentage of moving sperm. The aim of this study was to determine and compare the direct effects of some organic solvents(bisphenol A; BPA, dibutyl phthalate; DBP, formaldehyde; HCHO, dimethylsulphoxide; DMSO, ethanol) on mucus penetration distance, motility and survival rate of human sperm in vitro. Semen samples from 3 health subjects were prepared using swim-up method and 0.0005~0.5% organic solvents were added to the test medium. BPA, DBP, HCHO and DMSO produced significant decreases in the motility and survival rate with a different potency. The most potent inhibition of mucus penetration distance, motility and survival rate was observed after exposure to HCHO. A concentration of 0.0005% HCHO significantly inhibited sperm motility. When ethanol is added directly to sperm, at concentrations equivalent to that in serum after heavy drinking, these damaging effects were lowest compared with other solvents. Present study shows that each compound has different toxic potency to human sperm and we need special caution for the use of HCHO.

Ketoprofen 첩포제(Ketotop : )의 경피적용에 따른 혈장농도 및 피부자극의6 검토

임동석,장인진,신상구,유재학,은희철 大韓臨床藥理學會 1994 臨床藥理學會誌 Vol.2 No.1

이하선에 발생한 양성 림프상피성 병소

최순철,박태원,유동수,박래정 大韓口腔顎顔面放射線學會 1996 Imaging Science in Dentistry Vol.26 No.2

The authors diagnosed a 33 years old female as benign lymphoepithelial lesion after undergoing clinical, radiological and histopathological examinations and the characteristics were as follows: 1. Clinically, the patient complained of painless bilateral swelling of the parotid glands and dryness of the palate. Rheumatoid factor was detected in her serum. 2. Sialograms showed punctate or globular collections of contrast media distributed evenly throughout the parotid glands in so-called "cherry blossom"or "leafless fruit-laden tree" appearance. 3. A salivary gland scan showed no uptake of radioisotopes by the parotid glands. 4. At Tl-weighted imaging of PNS MRI, the lesions had the same signal intensity as the rest of the gland. At t2-weighted imaging, the lesions could be seen as high signal intensity 1.3 cm and 2.1 cm in diameter in the left and the right parotid gland respectively. 5. Ultrasonogram showed sonolucent lesions 20×15mm and 17×14mm in size in the lower part of the left parotid gland and another 18×11mm in size in the lower part of the parotid gland as well as many other small sonolucent lesions. 6. Histopathologically, lymphocytic infiltration replacing the normal acini and lymphoid follicles containing germinal centers could be seen. Epimyoepithelial islands were scattered throughout the lesion and benign lymphoepithelial cysts were also observed.

발달장애학생을 위한 웹기반 의사소통능력신장 프로그램의 개발과 적용 사례

김동현,유영환,김좌중,천경철,이청용,김봉수 국립특수교육원 2005 연구보고서 Vol.- No.10

발달장애학생의 의사소통능력은 단순한 언어문제 이상의 의미를 지닌다. 의사소통능력은 모든 학습의 기초가 되고 결국 인간의 삶의 질을 좌우하게 하는 중요한 요소가 되고 있기 때문에 의사소통능력에 문제가 많은 발달장애학생에게 있어서 의사소통능력 신장은 매우 중요하다. 발달장애학생의 언어 및 의사소통능력의 결함은 사회적 결함과 인지적 결함에 상호 관련성이 있어 다른 사람으로부터의 의사소통을 이해하는 능력과 자신의 생각을 표현하는 능력이 제한되어 다른 사람과의 상호관계를 맺는데 어려움이 많았다. 따라서 발달장애학생의 언어지도는 생활 장면에서 교수하는 것이 가장 바람직하다고 하겠다. 그러나 지금까지 주로 활용된 전통적인 언어지도 방법은 어휘를 증가시키고, 발화의 길이를 널리는 데는 효과가 있었지만, 학습된 내용을 생활 장면에서의 일반화에는 문제점이 있는 것으로 지적되고 있다. 발달장애학생의 언어지도 방법은 일상생활 속에서 학습 내용을 선정하고 이를 실생활 장면 혹은 이와 유사한 환경에서 효과적으로 지도할 수 있는 적절한 교수 방법이 필요하다. 그래서 발달장애학생의 의사소통능력 신장을 위한 환경중심 언어지도 방법을 활용한 웹(Web)기반 언어지도 프로그램을 개발하였다. 웹(Web)기반 언어지도 프로그램은 제7차 특수학교 기본교육과정과 국립특수교육원에서 발간한 ‘발달장애학생의 언어교육 프로그램(1998)’ 분석을 통하여 개인 · 가정생활, 학교 · 사회생활, 경제 · 여가생활 등의 6개 영역으로 구분하여 각 영역별 학습주제를 선정하였으며, 학습주제에 대한 학습의 진행 형태는 학습목표, 낱말학습, 상황학습, 평가로 진행할 수 있도록 하였으나, 학습자의 현재 수행 능력을 고려하여 능력에 따른 진행의 절차를 학습자가 선택할 수 있게 하였다. 본 프로그램을 적용해본 결과 다음과 같은 교육적인 효과를 얻을 수 있었다. 첫째, 웹을 활용한 가상체험을 통하여 적극적이고 흥미 있는 참여를 유도하며, 학습자 중심의 주도적인 학습과 안내자, 촉진자로서의 교사의 역할을 통해 발달장애학생의 의사소통 능력을 신장시킬 수 있었다. 둘째, 교실에서 이루어지는 지금까지의 수업방식을 탈피하여 학습자가 언제, 어디서나, 누구든지 학습할 수 있는 열린 학습체제의 교육환경을 조성할 수 있었다. 셋째, 문자정보, 그래픽, 애니메이션, 사진, 음성, 비디오 등 다양한 형태의 정보가 상호대화 형식으로 활용되며, 수준별 반복학습을 실시함으로써 교수-학습 방법의 개선뿐만 아니라 양질의 수업을 진행하는데 도움을 줄 수 있었다. 본 프로그램을 활용한 언어지도가 발달장애학생의 의사소통능력 신장을 위한 최선의 방법이라고 말할 수는 없으며, 언어지도의 한 가지 방법이라고 말할 수 있다. 따라서 본 프로그램의 활용한 언어지도는 학교에서 교사가 학생의 능력과 흥미를 고려하여 지도한다면 발달장애 학생의 의사소통능력 신장에 많은 도움이 될 것이다. The developmental disability of the metal handicapped children means more than simple linguistic problem. The developmental disability is the base of all the learning and important factor which decides the happiness of the human being finally, so the extension of mutual understanding ability is so important, in the case of the metal handicapped children who have a problem of the mutual understanding ability. In the case of the metal handicapped children, the defects of the mutual understanding and linguistic ability are related with the social defect and the defect of recognition, and the ability of understanding about mutual relations with other people and self-expression ability are limited. So they have many problems in mutual relations with other people. Therefore, the linguistic instruction of the metal handicapped children is recommended to be done in the living. But, the traditional linguistic instruction which's used mainly as yet, is effective in increase of a vocabulary and the length of a locutionary act, but it has a problem in the popularization of the learning in the real life. The method of the linguistic instruction for the metal handicapped children, should be selected as contents in the real life, and the right learning method which can be done under the real life or the similar environment with it, is needed. Because of the above realities, the linguistic teaching web-based program is developed, using the linguistic instruction which is focused on the environment, for the extension of the mutual understanding ability of the metal handicapped children. In the linguistic teaching web-based program, it is divided with 6 field (personal · home life, school · social life, economical · leisure life) and the educational subject classified by each field is selected, by the analysis of 'The linguistic educational program for the children who have developmental disability' published by the 7th basic education course of special school and the national special education organization. Besides, the progress form of learning about the educational subject is directed by educational goal, word learning, situation learning and valuation, but a learner can choose a procedure followed by ability, regarding to his accomplishment ability. As the result of the application of this program, the educational effects that we could get are the following : 1. We could lead a positive and interesting participation by virtual experience through WEB, and the communication ability of the metal handicapped children was extended by a role of a teacher, as a guide and promoter and a leading learning focused on a learner. 2. The teaching method which is done in school now, is dismissed and we could form the educational environment of the learning system that a learner could learn, without distinction of time, a place and a person. 3. The various form of information, like text, graphic, animation, photo, sound, video and so on, is applied as a form of communication. Therefore, the program was useful in not only the improvement of the teaching-learning method, but also the proceeding of the effective lesson. The linguistic teaching which use this program, can not be the best method of the extension of the mutual understanding ability and it's just one method of linguistic teaching. if the linguistic teaching which use this program is conducted, regarding to a ability and a interest of a student, it will be so useful in the extension of the mutual understanding ability, for the children who have developmental disability.

반도체 레이저의 이득곡선에서의 비포물선형 효과

김동철,유건호 慶熙大學校 레이저 工學硏究所 1997 레이저공학 Vol.8 No.-

Use of one-band model in the calculation of gain of semiconductor lasers is convenient because it is easy to understand and takes less time to implement. However, it gives an error in the gain by neglecting the nonparabolicity. In this paper, we study the limit of the one-band model by comparing the gain calculated by the one-band model with that by a multiband model. We find that, if the active layer is bulk, the peak gain by the one-band model is approximately same as that by a multiband model. However, if the active layer is a quantum well, the peak gain by the one-band model is much larger, and the one-band model may not be used for a quantitative analysis.

Congo Red에 의한 이질균 세포막 단백의 변화

강동민,이상화,이유철,설성용,조동택 慶北大學校 醫科大學 1991 慶北醫大誌 Vol.32 No.1

To study the correlation between virulence and Congo red binding capacity of Shigella, 2 invasive strains of Shigella flexneri to HeLa cell were subjected to investigate the regulation of levels of membrane proteins mediated by Congo red. Two tested strains were pigmented on the agar plate containing Congo red. Virulent S. flexneri grown in the presence of Congo red at 37℃ showed increased levels of three proteins with molecular weight of 43,000, 58,000, 63,000 daltons in the sodium lauryl sarcosinate(SLS) soluble membrane fractions and those proteins were also found in the total membrane fractions. But those proteins were not found in the SLS insoluble fractions. At 32℃ or 42℃, the protein levels in the SLS soluble fractions or SLS insoluble fractions unaffected by the presence of Congo red. The expression of these proteins was dependent to the incubation temperature.