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51.
Li YANG Jiang CHEN Catherine C. Y. CHANG Xin-Ying YANG Zhen-Zhen WANG Ta-Yuan CHANG and Bo-Liang LI* State Key Laboratory of Molecular Biology Institute of Biochemistry Cell Biology Shanghai Institutes for Biological Sciences the Chinese Academy of Sciences Shanghai China Department of Biochemistry Dartmouth Medical School Hanover NH USA 《Acta biochimica et biophysica Sinica》2004,(4)
Acyl-coenzyme A:cholesterol acyltransferase (ACAT)is an integral membrane protein, which is mainly locatedin rough endoplasmic reticulum (ER), and is responsiblefor catalyzing the intracellular formation of cholesterylester from cholesterol and long-chain fatty acyl-coenzymeA [1,2]. Human ACAT1 cDNA K1 was firstly cloned andfunctionally expressed in 1993 [3]. Further studies withspecific anti-ACAT1 antibody (DM10) illustrated that onemajor 50 kD ACAT1 protein was expressed in various… 相似文献
52.
张更谦 王艳 张艳霞 徐晓莉 邢小平 王英元 贠克明ZHANG Geng-Qian WANG Yan ZHANG Yan-Xia XU Xiao-Li XING Xiao-Ping WANG Ying-Yuan YUN Ke-Ming 《遗传》2004,26(3):0-297
为了应用更多的Y染色体特异性STR基因座以用于法医学和人类遗传学研究,本文用PCR结合PAGE技术检测128例山西汉族无关男性DYS605等位基因分布状况。结果显示:山西地区汉族男性DYS605基因座观察到22,21,20,19,18共5个等位基因,基因频率分别为0.0156;0.1797;0.4531;0.2891;0.0625。等位基因20和19之间的电泳距离在非变性胶上非常接近,要有足够的电泳距离才能区分。测序表明该基因座包括3个串联重复区,其中一个为可变重复区。20例女性DNA未发现扩增产物。Abstract: We study the polymorphism at DYS605 ,a new tetranucleotide Y-STR locus,in a Chinese Han population of Shanxi to meet the need of more genetic markers in forensic practice and genetic analysis. DNA were extracted from 128 unrelated male venous blood, and amplified using GDB primers. PCR products were detected using non-denaturing polyacrylamide gel electrophoresis and silver staining. Five alleles named 22,21,20,19,18 were observed with frequency of 0.0156;0.1797;0.4531;0.2891;0.0625. PCR products were not found in female DNA. Using a long enough gel for a long electrophoresis time is strongly encouraged because the rung between allele 20 and allele19 is smaller than expected. Allele sequences show that the repetitive units of DYS605 were composed with the variant units and non-variant units. 相似文献
53.
王吉振 储明星 王爱国 李宁 傅金恋 谢芳 陈国宏WANG Ji-Zhen CHU Ming-Xing WANG Ai-Guo LI Ning FU Jin-Lian XIE Fang CHEN Guo-Hong 《遗传》2004,26(5):637-647
分析了4个微卫星基因座BM143、OarHH35、OarAE101、BMS2508在7个绵羊群体(小尾寒羊、湖羊、乌珠穆沁羊、萨福克羊、多赛特羊、夏洛来羊、多赛特公羊×小尾寒羊母羊F1代杂种羊)286只绵羊中的遗传多态性。结果表明,这4个微卫星标记在7个绵羊群体中的等位基因数分别为9、11、14和9,其多态信息含量/有效等位基因数/杂合度分别为0.7073/3.7231/0.7314、0.8267/6.4399/0.8447、0.5743/2.5178/0.6028、0.6172/3.0712/0.6744,其中OarHH35的遗传变异最大,OarAE101最小。7个绵羊群体中小尾寒羊的遗传变异最大,湖羊的最小。基于Nei氏DA距离和DS标准遗传距离,采用UPGMA方法构建了系统发生树。该发生树将中国地方品种(小尾寒羊、乌珠穆沁羊、湖羊)和法国的夏洛来羊归为一类,将F1杂种羊、英国品种(萨福克羊和多赛特羊)归为另一类。绵羊微卫星基因分型技术为检查品种(群体)之间的遗传关系提供了一个有用的工具。
Abstract:The genetic polymorphisms of four microsatellite loci BM143,OarHH35,OarAE101,and BMS2508 were analyzed in 286 sheep of seven sheep populations (Small Tail Han sheep, Hu sheep, Ujumqin sheep, Suffolk sheep, Dorset sheep, Charolais sheep, F1 of Dorset♂ × Small Tail Han sheep♀). The numbers of alleles for BM143,OarHH35,OarAE101,and BMS2508 are 9, 11, 14 and 9 in seven sheep populations, respectively. The polymorphism information content/number of effective alleles/ heterozygosity of BM143,OarHH35,OarAE101 and BMS2508 were 0.7073/3.7231/0.7314, 0.8267/6.4399/0.8447,0.5743/2.5178/0.6028,0.6172/3.0712/0.6744
in 286 sheep, respectively. The results revealed the greatest genetic variation at OarHH35 locus and the lowest at OarAE101, the greatest genetic variation in Small Tail Han sheep and the lowest in Hu sheep among seven sheep populations. In the unweighted pair group method with arithmetic mean (UPGMA) dendrograms based on Nei's DA distance and Nei's DS standard genetic distance, the Chinese native breeds (Small Tail Han sheep, Ujumqin sheep, Hu sheep) were grouped together, then with Charolais sheep. The F1 crossbred sheep, and the two British native sheep (Suffolk sheep, Dorset sheep) also clustered together. Microsatellite genotyping in sheep provided a useful tool for examining the genetic relationships among breeds(populations). 相似文献
54.
The complete mitochondrial genomes sequences of Asio flammeus and Asio otus and comparative analysis 总被引:2,自引:0,他引:2
SUN Yi MA Fei XIAO Bing ZHENG Junjie YUAN Xiaodong TANG Minqian WANG Li YU Yefei & Li Qingwei . College of Life Sciences Liaoning Normal University Dalian China . TaKaRa Biotechnology 《中国科学:生命科学英文版》2004,47(6):510-520
Mitochondrial DNA (mtDNA), as a model sys-tem, has been extensively used for molecular phy-logenetic and evolutionary analysis[1]. With the ad-vances in DNA sequencing technology, more andmore researchers prefer to use complete mitochondrialgenome for phylogenetic analysis[2—4]. Since the com-plete sequencing of human mtDNA in 1981 (Andersonet al., 1981)[5], 342 vertebrate mitochondrial genomeshave so far been sequenced. Up to now the completesequences of 29 avian mitochondrial genomes h… 相似文献
55.
WANG Fengqiang SHANG Boyang & ZHEN YongsuInstitute of Medicinal Biotechnology Chinese Academy of Medical Sciences & Peking Union Medical College Beijing China 《中国科学:生命科学英文版》2004,47(1):66-73
Type IV collagenase plays an important role in tumor invasion and metastasis through cleaving type IV collagen in the basement membrane and extracellular matrix. In this study a molecule-downsized immunoconjugate (Fab'-LDM) was constructed by linking lidamycin (LDM), a highly potent antitumor antibiotic, to the Fab' fragment of a monoclonal antibody directed against type IV collagenase and its antitumor effect was investigated. As assayed in 10% SDS-PAGE gel, the molecular weight of Fab'-LDM conjugate was 65 kD with a 1 : 1 molecular ratio of Fab' and LDM. The Fab'-LDM conjugate maintained most part of the immunoreactivity of Fab' fragment to both type IV collagense and mouse hepatoma 22 cells by ELISA. By MTT assay, Fab'-LDM conjugate showed more potent cytotoxicity to hepatoma 22 cells than that of LDM. Administered intravenously, Fab'-LDM conjugate proved to be more effective against the growth of subcutaneously transplanted hepatoma 22 in mice than free LDM in two experiment settings. In Experiment 相似文献
56.
SHI Zhaoxing* WANG Hengliang* HU Kun FENG Erling YAO Xiao HUANG Liuyu SU Guofu HUANG Peitang & HUANG Cuifen . Beijing Institute of Biotechnology Beijing China . College of Life Science Shandong Normal University Jinan China . College of Environmental Chemical Engineering Xi’an Jiaotong University Xi’an China Correspondence should be addressed to Huang Liuyu 《中国科学:生命科学英文版》2004,47(6):494-502
~~Screening and identification of Shigella flexneri 2a virulence-related genes induced after invasion of epithelial cells1. Jin, Q., Yuan, Z., Xu, J., Wang, Y., Shen, Y., Lu, W., Wang, J., Liu, H., Yang, J., Yang, P., Zhang, X., Zhang, J., Yang, G, Wu, H., Qu, D., Dong, J., Sun, L., Xue, Y, Zhao, A., Gao, Y., Zhu, J., Kan, B., Ding, K.. Chen, S., Cheng, H., Yao, Z., He, B., Chen, R., Ma, D., Qiang, B., Wen, Y, Hou, Y., Yu, J., Genome sequence of Shigella flexneri 2… 相似文献
57.
WANG JI WU JIA RUI WU State Key Laboratory of Molecular Biology Institute of Biochemistry Cell Biology Shanghai Research Center of Life Science Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Yue- Yang Road Shanghai 《Cell research》2001,(4)
INTRODUCTIONDNA replication is a fundamenial process thatmust occur only once at each ce1l cycle. This restrictcontrol appears to be achieved through the coordi-nated actiVities of numerous proteins. The buddingyeast Saccharompes cerevhaae provides an excellenteukaryotic model fOr study of proteins invo1ved inthe control of DNA replication.In the budding yeast, minichromosome mainte-nance (MCM) proteins, MCM2-7, are a family of strsequence-related proteins that play crucia1 roles inr… 相似文献
58.
ZAMORANO JOSE Unidad de Investigacion Hospital San Pedro de Alcantara Avda Millan Astray Caceres ANN E KELLY JONATHAN AUSTRIAN HELEN Y WANG ACHSAH D KEEGAN 《Cell research》2001,(1)
INTRODUCTIONThe inappropriate enhancement of lymphocytesurviVal due to a block in programmed cell deathand/or an enhancement of entry into the cell cyclecan contribute to the abnormal expansion of clonesresulting in tumorigenesis or the breakdown of pe-ripheral self-toleranced, 2]. Proper lymphocytehomeostasis is critical for normal immune functionand is maintained by a complex series of cellularinteractions and the action of secreted cytokines.Illterleukin-4 (IL-4), a cytokine produced … 相似文献
59.
我们创建了一个新的染色体模型:YR-黏和染色体模型,30nm螺线管通过JW-梯(或YR-梯)、染色线经螺旋化形成染色体[1].通过包装比、长度的推算、染色体结构的推算、以及碱基对的推算都与实验观测值吻合,确认了YR-黏和模型的可信度.YR-染色体模型能自然、合理地解释所有遗传现象,如交换、着丝粒、全身着丝粒或弥散型着丝粒染色体、同源染色体联会及联会复合体的中央区、多线染色体与膨突、灯刷染色体、染色体分带、姊妹染色体由前期到中期不分开、花粉管会导入外源遗传物质、高等生命是怎样从原始生物进化而来的等等。
Abstract:We provide a chromosome model YR-cohesion chromosome model.30nm solenoid fold and bent through JW-ladder and chromonema spiraling to chromosomeIll.It is checked by this calculation of picked ration,length,chromosomal structure and DNA base pairs,which are all consonant with practical resultsIll.YR-cohesion chromosome model will give a better answer to the questions such as exchange,centromere,holocentromere,synaptonemal complex,polytene chromosome,puff,lampbrush chromosome,chromosome banding,non-segregation of sister chromatid,pollentube pathway and biological evolution. 相似文献
60.
本文参阅有关文献及十多年遗传学教学中所使用的不同版本的教材,对郭德栋主编的<遗传学>教材中的若干问题进行了商榷。
Abstract:Consulted some reference books and textbooks of different versions used over ten years,we are about to discuss some problems in the textbook “Genetics” edited by Guo De-dong in this paper. 相似文献