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        SV40 T 항원의 온도조건부 변이형 유전자가 포함된 Amphotropic Retrovirus 에 의한 사람 태아 간세포의 불멸화

        이정일(Joung Il Lee),동석호(Seok Ho Dong),김효종(Hyo Jong Kim),김병호(Byung Ho Kim),장영운(Young Woon Chang),장린(Rin Chang),성세라(Se Ra Seong),박재경(Jae Kyung Park),김승보(Seung Bo Kim),이상목(Sang Mok Lee) 대한내과학회 1999 대한내과학회지 Vol.57 No.1

        N/A Human cells are almost never spontaneously immortalized in vitro. We tried to immortalize human fetal hepatocytes (h-FH) and evaluate the differentiational status and its change. Methods : Hepatocytes were isolated from a liver fragment of 20 week old fetus and infected with amphotropic recombinant retrovirus containing a temperature- sensitive mutant of SV40 large T antigen and neomycin phosphotransferase gene. G418 resistant colonies were cloned and expanded. The cells which were able to divide more than 30 times were used to analyze various functions. Results : The immortalization rate was 3.3 x 10-8 and two cell lines (C11, D21) were established. C11-60, C11-80, D21-30 and D21-60 (suffix number means the cell division counts) were evaluated. D21-30 was thougt to be imcompletely immortalized because a considerable portion of cells died during culture. The morphology was similar to that of epithelial cells except for D21-30 which looked like fibroblast. The cells grew rapidly at 33oC but stopped growing at 39oC. T antigen and p53 was expressed at 33oC but disappeared at 39oC, which suggest that T antigen binds to p53. Chromosomal changes were so marked that it was impossible to discriminate exact number. Albumin was secreted as about 1/10 as that of h-FH, but alpha-fetoprotein secretion stopped after immortalization. Telomerase was activated in both cell lines except for the incompletely immortalized cells D21-30. Telomere was elongated in competely immortalized cell lines, but it was rather shortened in D21-30 compared to that of h-FH. Macroscopic colonies did not develop in soft agar assay. Conclusions : We successfully immortalized human fetal hepatocytes. Although the cells are not likely to have oncogenicity, the functions are not so good, possibly due to marked chromosomal changes which are thought to occur before telomerase is activated during immortalization step.

      • 154kV용 활선 안전 경보기 개발에 관한 연구

        정민규,조현광,우종수,안창회,서영석,김응태,박창기,오세득 영남대학교 공업기술연구소 2000 工業技術硏究所論文集 Vol.28 No.1

        In this report we developed a high voltage alarm for the safety of workers who check and repair the 154kV power line. This high voltage alarm we developed is attached on workers' helmet and alarms automatically in order to let workers know when workers work over the safety distance near 154kV power line. Until now the exact safety distance hasn't been regulated and high voltage alarm we've been using was for the range of 6∼22.9kV power line. We fabricated this high voltage alarm on the basis of electric density and actual measurement of power line. The experimental result was that high voltage alarm at 66kV power line alarmed near 90cm, at 154kV power line alarmed near 160cm from the line. Accordingly, we developed the new high voltage alarm which is operated in the range of 66∼154kV power line.

      • X-band 주파수대역에서 동작하는 다이오드 주파수 혼합기 설계 및 제작

        정민규,서영석,안창회 영남대학교 공업기술연구소 2000 工業技術硏究所論文集 Vol.28 No.2

        In this paper reports on the design and performance of microstrip single balanced diode mixer, using GaAs Schottky diode, at X-band. A single balanced diode mixer is designed and implemented using Harmonic balance simulation(MW-office). The diode model parameters are extracted by SPICE model of diode. The diode impedances for the LO, RF, and IF frequencies and Powers are calculated for diode matching network design. The mixer consists of branch line coupler, Low pass filter and RF&LO choke for bias circuit. The Passive circuits are simulated for accuracy by EM-simulation of MW-office. The Mixer requires 10dBm local oscillator(LO) power without dc bias and achieves a conversion loss of about 7.5dB, 17dB LO-to-RF isolation, 40dB LO-to-IF isolation, 30dB RF-to-IF isolation, and 1.16 LO VSWR.

      • 작업구역의 합리적 분할에 의한 택트공정관리 개선

        정영권,윤유상,서상욱,신동우,김창덕,김경래 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.1

        The purpose of this study is to increase the operational efficiency of Tact Planning and Scheduling through effective labor control based on fairly reasonable creation of work area. The main result of the study are as follows: 1) Specific section of work area for electric work lead to no division of zone between internal residence area and bathroom. And designate the work area of each floor so that it would manage labor control effectively. 2) When it comes to equipment work. It set up work area according to "floor" taking account into more frequent unit work comparatively than floor work. The study recommends that. As a future research, eventually aims at establishment of integrated system of labor control Tact Planning and Scheduling by combining respectively divided system into one.

      • 여행속도에 따른 Q-V관계식 산정에 관한 연구

        임채문,정우영,공창환,홍익상 대구대학교 과학기술연구소 1995 科學技術硏究 Vol.2 No.1

        The purpose of this study is to estimate a suitable traveling speed model based on using the traffic data collected by test-vehicle traveling method and the data on road geometric and operating characteristics. The conclusions of this study are as follows. In travel speed model(Q-V), regression model (V=9.635+0.0169L - 0.00045Q - 2.1926N, R²=0.76) the important independent variables are speed is closely related with distance, traffic volume and the number of traffic lane, form the result of speed-flow regression analysis, link travel speeds are influenced by link distance, traffic volume, and the number of lanes. As expectedly by the most significant factor influencing link travel speeds. The changing of traveling speed according to section distance is appeared large. According to the result of analysis of travel speed and traffic density model(Q-K), as according the that density increases the travel speed is decreases, on the other hand travel speed increases, the density decreases. The speed equation (u=68.72e^(-k/22.6)) is derived by form the Q-K relationships founded form the study, traffic volume increases as traffic speed increase up to the critical traffic density. If traffic volume decreases when traffic density is abduce the critical traffic density. Using Q-V equation estimated by regression analysis and Q-K equation estimated by density, Traffic value test was accomplished by computer program(TRANPLAN). There were difference between too test, however, the deviation was small. On case of using program, the application extent we considered, is between 25Km/h - 60Km/h. Traffic volumes obtained from TRANPLAN are governably 10% larger than traffic volume estimated form Q-K model. However the difference of the critical traffic density bow Q-K model and TRANPLAN, are relatively small. It is desirable to reduce traffic volume by 0.7∼9% over all, speed range when TRAPLAN is applied in Q-K relationship.

      • 대구시 간선가로망 구축에 의한 입체 교차로의 효율성에 관한 연구

        임채문,공창환,정우영 大邱大學校 科學技術硏究所 1994 科學技術硏究 Vol.1 No.-

        It is necessary to establish a link organization to device the transportion planning relieving traffic congestion. Therefore, this study has established a principal link centering around Taegu city, and reviewed the efficienay of the grade intersations and the 3-Dimensional intersations. The results of this study are as fallow; This study has established each circulation lane by Grid partition and Daiiy Traffic Volume (the 1st circulation lane; 000m, the 2nd circulation lane; 800m, the 3rd circulation lane; 1000m) The delay model of a length is t₂= exp(3.0091 +0.001242x)k (R²=0.78). The conversion of traffic volume into turning point the grade and 3-Dimensional intersection at single intersection is different by the distance between intersections. The decrease of total link delay is minute by one or two 3-Dimension on a intersection, and the 3-Dimension on the 2nd and and circulation lane is more effective than the 1st circulation lane. In the case of multi-intersections, passing time on the 3-Dimension passing throuth the urban center and the bypassing road has a little difference. For that reason, the bypassing route must be considerd instead of the 3-Dimension passing throuth the unban center. So an examination and re-settlement of the future pricipal link is necessary to organze the principal link on Taegu city using other factor.

      • 활성형 Vitamin D₃ 전환능을 소유한 방선균에서 P-450 Hydroxylase유전자의 클로닝 전략

        서주원,현창구,김정미,김승영,홍순광 명지대학교 자연과학연구소 1998 자연과학논문집 Vol.17 No.-

        비타민 D₃는 포유동물이나 새의 간에서 25-hydroxyvitamin D₃[25(OH)D₃]로 전환되는데, 이 hydroxylation은 P-450 hydroxylase에 의해 촉매된다고 알려져있다. 본 연구에서는 활성형 비타민 D₃전환능을 소유한 방선균에서P-450 hydroxylase효소를 신속하게 분리가능한 PCR방법을 보고하고자 한다. Primer는 방선균에서 보고된 P-450 hydroxylase들 사이의 아미노산 서열의비교를 통해 산소결합부위와 heme-ligand pocket 주의에서 제작되었고,5종의 방선균에서 효과적으로 PCR증폭산물을 획득할 수 있었다. 증폭산물을 획득할 수 있었다.증폭 산물들의 아미노산서열을 분석한 결과 기존에 밝혀진 많은P-450 hydroxylase유전자들과 상동성을 보이고 있었으며, 특히 Streptomyces griseolus에서 분리되어 sulfonylurea 등의 제초제의 분해능력을 가진 SuaC, SubC 효소 등과 높은 아미노산 상동성을 지니고 있었다. 이러한 PCR전략은 방선균에서 유용한 물질의 대사에 관여하는 P-450 hydroxylase효소의 클로닝에 도움을 줄 것이라 사료된다 In mammals and birds, vitamin D₃is converted to 25-hydroxyvitamin D₃[25(OH)D₃] and then to 1α25-dihydroxyvitamin D₃[25(OH)₂D₃]in the liver and kideny, respectively these hydroxylating reactions are known to be catalyzed by P-450 hydroxylases. In this paper we report a PCR method which can be used for the repid amplification of DNA fragments for _450 hydroxylase from actinomycetes which can convert to active from of vitamin D₃. Primers were designed based on several regions sharing strong similarities in amino acid sequence of P-450 hydroxylases from a variety of actinomycetes, primarily in the regions of an oxygen binding site and a heme ligand pocket. These primers were used to amplify DNA fragments from five different actinomycetes. The deduced amino acid sequences of the isolated fragments revealed significant similarities to known P-450 hydroxylase including the product of the suaC or subC genes from Streptomyces griseolus that is capable of metabolizing a number of sulfonylurea herbicides and to the product of the P450sca2 from S. carbophilus that produces a specific HMG-CoA reductase inhibitor. This method will be helpful for the researchers in cloning the genes for P-450 hydroxylase involved in the biosynthesis of useful compounds.

      • 주의력 결핍 과잉행동 장애 아동에서의 집단 프로그램의 치료 효과

        심세훈,오창근,권자영,정유숙,홍성도 순천향의학연구소 2003 Journal of Soonchunhyang Medical Science Vol.9 No.1

        Background : The authors attempted to introduce group program for improving interpersonal relationship and evaluate the effects of that program. Material and Methods : This program had been held twice a week for 8 weeks for children and parents training had been for times on the treatment and continued from 2001 to 2002. Twenty-five ADHD children in school age were selected as subjects from child psychiatric clinic of a general hospital in Seoul. Treatment outcomes were evaluated by comparing at pre- and post- treatment using the various rating scale. Result : According to the results of statistical analysis, paired t-test, the score of total self-concept including popularity was increased and family environment and parenting stress were improved significantly. These results suggest that this program is useful for its orginal goal. The parents evaluated also that children's total problem behaviors were decreased. Conclusion : These results suggest that the designed and performed group program in this study would be effective in facilitating ADHD children's emotional and interpersonal growth, and decreasing their parents stress. Finally they would have healthy interpersonal reationship.

      • KCI등재

        SWS 490A 강의 용접 열영향부 음향방출 특성에 대한 연구(1)

        이장규,우창기,박성완,윤종희,조진호,김봉각,구영덕 한국공작기계학회 2004 한국생산제조학회지 Vol.13 No.4

        The object of this study is to investigate the effect of compounded welding through the AE(Acoustic Emission) characteristics for weld HAZ(Heat Affected Zone) under the static tensile test. This study was carried out an SWS 490A, high tension steel for electric shield metal arc welding(SMAW), CO₂gas arc welding and TIG welding. Data displays are based on the measured parameters of the AE signals, along with environmental variables such as time and load. The accumulated AE event curve of HAZ definitely have the point of inflection subject to tensile test. The results of the tensile test of HAZ come out electric shield arc welding > CO₂ gas arc welding >TIG welding in case of single welding, but generally the tensile test of HAZ come out electric shield arc welding > TIG welding > CO₂ gas arc welding. These history plots give us useful and powerful information to analyze the results of material evaluation testing.

      • 信號交叉路의 交通特性과 左回轉 禁止에 따른 運營效果에 관한 硏究

        홍익상,공창환,정우영,임채문 대구대학교 산업기술연구소 1993 産業技術硏究 Vol.12 No.-

        This study analyzed the characteristics of the operation of left turns at intersections of the streets in Taegu City. The points of the study were as follows: increase of traffic capacity, decrease of delay time, and to do so this study aims at seeking a way for the most appropriate signal cycle and an effective way to operate intersections. The following are the results: 1st The arterials of Taegu City have a high rate of left turns, and yet are not divided into specific functions, which impairs the efficient use of the functions. It is required that a study be made on the way of utilizing the left turn to the maximum of the operational functions of signalized intersections. 2nd As traffic volume and left turn ratio increase, it was revealed that the optimum signal cycle and delay increased, adoption of efficient lanes was analysed to be most effective at the intersection which have a great of traffic volume and a high or rate of left turns. 3rd On the independent intersection in Taegu city, when left turn is prohibited, it may give poor approaches, but according to analyses this will bring a phenomenal decrease in the optimum signal cycle and delay.

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