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71.
The effects of proteasome inhibitor lactacystin on mouse oocyte meiosis and first cleavage 总被引:1,自引:0,他引:1
TAN Xin PENG An WANG Yongchao & TANG Zuoqing . School of Life Sciences Technology Beijing Institute of Technology Beijing China . College of Life Sciences Beijing Normal University Beijing China . College of Basic Medicine Capital University of Medical Sciences Beijing China 《中国科学:生命科学英文版》2005,48(3):287-294
Many studies have shown that the ubiq-uitin-proteasome pathway (UPP) for the degradation of short-lived proteins plays a key role in regulating cell cycle progression[1—3]. At least two distinct prote-olytic pathways are required for cell cycle process. The first pathway promotes transition from G1 to S phase, and the second initiates the onset of anaphase and exit from mitosis. The inhibition of UPP will re-sult in the blockage of cell cycle process. The knowl-edge of the role of UPP in… 相似文献
72.
SUN Xiangqing * JIA Yanbin * ZHANG Xuegong XU Qi SHEN Yan & LI Yanda . Ministry of Education 《中国科学:生命科学英文版》2005,48(3):263-269
Schizophrenia is a serious neuropsychiatric illness affecting about 1% of the world’s population. Family, twin and adoption studies have demonstrated that 65%―85% of the susceptibility to schizophrenia can be attributed to genes. On the basis of genetic model-ing of epidemiological data and recent results of a number of whole-genome screens for susceptibility genes, schizophrenia has been considered a complex disorder. A number of genes with small to moderate effects are involved in combinat… 相似文献
73.
CHEN Ruijuan JIANG Jiangang XIAO Xiao & WANG Daowen . The Institute of Hypertension Department of Internal Medicine Tongji Hospital Tongji Medical College Huazhong University of Science & Technology Wuhan China . Departments of Molecular Genetics Biochemistry & Gene Therapy Center University of Pittsburgh Pittsburgh PA USA 《中国科学:生命科学英文版》2005,48(5):495-505
Vascular endothelial cells play crucial roles in regulating cardiovascular function, maintaining car-diovascular homeostasis and preventing the occur-rence of cardiac and cerebral vascular diseases. All these protective effects are fulfilled through various vasoactive products secreted by endothelium including nitric oxide (NO), prostacyclin (PGI2) and endothe-lium-derived hyperpolarizing factor (EDHF). NO, pro-duced from L-arginine by endothelial nitric-oxide synthase (eNOS), is an impor… 相似文献
74.
REN Yuanyuan DAI Xiuyu ZHOU Jian LIU Jingfang PEI Huadong & XIANG Hua . State Key Laboratory of Microbial Resources Center for Molecular Microbiology Institute of Microbiology Chinese Academy of Sciences Beijing China . Graduate School of Chinese Academy of Sciences Beijing China 《中国科学:生命科学英文版》2005,48(3):221-227
Trehalose is a non-reducing disaccharide of glucosewidely distributed in microorganisms, plants and in-sects. It usually functions as a compatible solute in thestabilization of biological structures under several en-vironment stresses[1,2]. Trehalose has proved to be anactive stabilizer of enzymes, proteins, biomasses, pharmaceutical preparations and even organs fortransplantation. Thus much attention has been paid tothe synthesis pathway of trehalose and the develop-ment of novel and economic… 相似文献
75.
Tyroserleutide tripeptide affects calcium homeostasis of human hepatocarcinoma BEL-7402 cells 总被引:1,自引:0,他引:1
FU Zheng LU Rong LI Guoli ZHAO Lan GAO Weizhen CHE Xuchun JIAN Xu ZHOU Chunlei & YAO Zhi . Department of Immunology Tianjin Medical University Tianjin China . Shenzhen Kangzhe Pharmaceutical Co. Ltd. Shenzhen China . Department of Pharmacy Tianjin Medical University Tianjin China . Central Laboratory of Tianjin Medical University Hospital Tianjin China 《中国科学:生命科学英文版》2005,48(5):523-530
Copyright by Science in China Press 2005 Primary hepatocarcinoma is one of the most fre-quent digestive-tract cancers, particularly in China. The incidence and death rate of primary hepatocarci-noma in China is the highest in the world, with about 1100 thousands people dying from primary hepatocar-cinoma per year[1]. Although the chemotherapeutic agents are the main therapeutic approach for hepato- carcinoma, they are relatively ineffective and result in many toxic and side effects. Accordin… 相似文献
76.
Comparative analysis of the pig BAC sequence involved in the regulation of myostatin gene 总被引:2,自引:2,他引:0
YU Zhengquan LI Yan MENG Qingyong YUAN Jing ZHAO Zhihui LI Wei HU Xiaoxiang YAN Bingxue FAN Baoliang YU Shuyang & LI Ning .State Key Laboratory for Agrobiotechnology China Agricultural University Beijing China .Beijing Genomics Institute / Genomics Bioinformatics Center Institute of Genetics Development Biology Chinese Academy of Sciences Beijing China 《中国科学:生命科学英文版》2005,48(2):168-180
Myostatin (GDF-8, MSTN) is a member of trans- forming growth factors (TGF-β) superfamily, which was first described by McPherron et al. in 1997[1]. Myostatin appears to act as a negative regulator of muscle development and controls not only fibre size but also fibre number[2,3]. Mutations in the third exon of the myostatin gene have been shown to cause dou- ble muscling in cattle[4]. By knocking out the gene of myostatin in mice, they were able to show that the transgenic mice developed … 相似文献
77.
从二色补血草中分离出一条含有完整开放读码框(ORF)序列的OEE2基因。该基因全长994bp,其中5’非翻译区27bp,3’非翻译区160bp,ORF全长807bp,共编码264个氨基酸,编码蛋白的分子量为28.2kDa,理论上的等电点为7.66。BlastP分析表叽二色补血草OEE2与马铃薯OEE2序列同源性最高,与喇叭水仙OEE2序列同源性最低,从9个物种的氨基酸多序列比对中可以看出,OEE2的氨基酸序列保守性较高。实时定量RT.PCR方法检测该基因对低温、NaCl和聚乙二醇(PEG)胁迫的基因表达模式的结果表明,PEG和低温能诱导OEE2基因在二色补血草叶中表达,这两种处理的OEE2基因表达量于胁迫48h后都达到高峰,而在NaCl胁迫下OEE2在二色补血草根和叶中表达都受抑制。 相似文献
78.
枯草杆菌的芽胞在肉鸡肠道中的生活状态和分布 总被引:2,自引:0,他引:2
目的探讨枯草芽胞杆菌的芽胞在肉鸡肠道中的生活状态和分布。方法以20日龄AA肉鸡为研究对象,饲喂枯草芽胞菌剂,分别测定鸡粪中芽胞数量和鸡肠道不同部位的活菌数量。结果饲喂3h后,鸡粪中开始检测到芽胞的存在,24h达到最高值,直至饲喂120h后,肠道内的芽胞基本排除。排出芽胞总量为饲喂芽胞总数的3.0倍左右,同时研究还表明:芽胞在实验肉鸡的十二指肠2内开始萌发,并进行了繁殖,在小肠的后端,即小肠3和小肠4,活菌数量达到高峰。结论部分芽胞进入小肠后即可开始萌发,并进行生长繁殖,而且在肠道内有短暂滞留。 相似文献
79.
从渤海海域(121°30′00″E,40°25′00″N)海泥中筛选到一株产碱性纤维素酶的海洋细菌。通过形态观察、生理生化特性及16SrDNA序列分析,鉴定该菌株属于芽孢杆菌属(Bacillus),命名为Bacillussp.HN07。研究表明:HN07最适生长温度30℃,适宜在pH7.0~8.0、含2.0%~3.0%NaCl的培养条件下生长和产酶,并且具有较好的遗传稳定性。酶学性质初步研究显示,HN07所产碱性纤维素酶最适反应温度为45℃,最适pH为8.0,在碱性条件下具有较好的稳定性,具有潜在的工业应用价值。 相似文献
80.
MENG Yan ZHAO ChunYan ZHANG XueXin ZHAO HuaShan GUO LiRong Lü Bin ZHAO XueJian& YANG BaoXue Department of Pathophysiology School of Basic Medicine Jilin University Changchun China Department of Physiology Department of Medicine University of California San Francisco CA USA 《中国科学:生命科学英文版》2009,52(5):474-478