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961.
962.
我们阐述的是关于俄罗斯消费者对女式西服上装的喜好。在俄罗斯著名的纺织重镇伊万诺沃.女性人口分为不同的社会群体.以其作为研究对象.我们采用2种方式来分析她们心中21世纪初理想正装上衣的概念。一是用较为大众传统的方法.既收集20-50岁年龄阶段女性的意见来分析:而另一种则是单独用数据的方法来研究。我们以表格的形式列出一件现代女式正装上衣内部结构上的一些参数:(1)衣长到臀围线。(2)驳头的宽度在其极限值范围的1/4-1/2处取值。(3)驳头宽和翻领宽相等。通过我们的研究所得结论希望能对中国向俄罗斯出口的成衣生产起到帮助。  相似文献   
963.
The proliferation ability of satellite cells (considered the 'stem cells' of mature myofibers) declines with increasing age when cultured under standard cell culture conditions of 21% oxygen. However, actual oxygen levels in the intact myofiber in vivo are an order of magnitude lower. No studies to date have addressed the issue of whether culturing satellite cells from old muscles under more 'physiologic' conditions would enhance their proliferation and/or differentiation ability. Therefore, we analyzed satellite cells derived from 31-month-old rats in standard cultures with 21% O2 and in lowered (∼3%) O2. Under the lowered O2 conditions, we noted a remarkable increase in the percentage of large-sized colonies, activation of cell cycle progression factors, phosphorylation of Akt, and downregulation of the cell cycle inhibitor p27Kip1. These data suggest that lower O2 levels provide a milieu that stimulates proliferation by allowing continued cell cycle progression, to result ultimately in the enhanced in vitro replicative life span of the old satellite cells. Such a method therefore provides an improved means for the ex vivo generation of progenitor satellite cell populations for potential therapeutic stem cell transplantation. Received 20 April 2001; received after revision 28 May 2001; accepted 31 May 2001  相似文献   
964.
Phylogeography of crossbills, bullfinches, grosbeaks, and rosefinches   总被引:1,自引:0,他引:1  
Mitochondrial cytochrome b (cyt b) from 24 Carduelini species including crossbills, bullfinches, grosbeaks, rosefinches, and other related, but not conclusively classified species, was sequenced. These sequences were also compared with all the available sequences from the genera Carduelis, Serinus, and Passer. Phylogenetic analyses consistently gave the same groups of finches and the calculated divergence times suggest that speciation of the studied species occurred between 14 and 3 million years ago (Miocene-Pliocene), appearing before the Passer, Carduelis, and Serinus genera. Pleistocene glaciations may have been important in sub-speciation. Crossbills are integrated within the genus Carduelis, and within redpolls; the common crossbill shows subspeciation with Loxia japonica in the Pleistocene epoch. Pinicola enucleator groups together with bullfinches and is probably the ancestor of the group. Hawfinch is only distantly related to the studied groups, and might either represent an isolated genus or be related to the New World genus Hesperiphona. The grosbeak genera Eophona and Mycerobas are clearly sister groups, and species belonging to the former might have given rise to Mycerobas species. The isolated (in classification) Uragus sibiricus and Haematospiza sipahi are included within the genus Carpodacus (rosefinches); Carpodacus nipalensis is outside the genus Carpodacus in the molecular analyses and might be an isolated species or related to the genus Montifringilla.  相似文献   
965.
966.
Endangered species and the law.   总被引:10,自引:0,他引:10  
V Geist 《Nature》1992,357(6376):274-276
Taxonomy does not deserve its reputation as an arcane science. As the following examples from ungulate taxonomy show, classification has important implications for conservation legislation.  相似文献   
967.
Human aminopeptidase N is a receptor for human coronavirus 229E.   总被引:62,自引:0,他引:62  
Human coronaviruses (HCV) in two serogroups represented by HCV-229E and HCV-OC43 are an important cause of upper respiratory tract infections. Here we report that human aminopeptidase N, a cell-surface metalloprotease on intestinal, lung and kidney epithelial cells, is a receptor for human coronavirus strain HCV-229E, but not for HCV-OC43. A monoclonal antibody, RBS, blocked HCV-229E virus infection of human lung fibroblasts, immunoprecipitated aminopeptidase N and inhibited its enzymatic activity. HCV-229E-resistant murine fibroblasts became susceptible after transfection with complementary DNA encoding human aminopeptidase N. By contrast, infection of human cells with HCV-OC43 was not inhibited by antibody RBS and expression of aminopeptidase N did not enhance HCV-OC43 replication in mouse cells. A mutant aminopeptidase lacking the catalytic site of the enzyme did not bind HCV-229E or RBS and did not render murine cells susceptible to HCV-229E infection, suggesting that the virus-binding site may lie at or near the active site of the human aminopeptidase molecule.  相似文献   
968.
969.
Hypervariable 'minisatellite' regions in human DNA   总被引:93,自引:0,他引:93  
A J Jeffreys  V Wilson  S L Thein 《Nature》1985,314(6006):67-73
The human genome contains many dispersed tandem-repetitive 'minisatellite' regions detected via a shared 10-15-base pair 'core' sequence similar to the generalized recombination signal (chi) of Escherichia coli. Many minisatellites are highly polymorphic due to allelic variation in repeat copy number in the minisatellite. A probe based on a tandem-repeat of the core sequence can detect many highly variable loci simultaneously and can provide an individual-specific DNA 'fingerprint' of general use in human genetic analysis.  相似文献   
970.
Leprosy, a chronic infectious disease afflicting between 10 and 15 million people, is caused by the obligate intracellular parasite Mycobacterium leprae. Although M. leprae was the first identified bacterial pathogen of man, basic biochemical, immunological, diagnostic and therapeutic investigations have been severely limited because it remains one of the few human pathogens that have not been cultured in vitro. An M. leprae recombinant DNA expression library was constructed to provide a source of genes encoding proteins relevant for such studies. Monoclonal antibodies directed against M. leprae specific antigens have been used to isolate the genes encoding the five most immunogenic protein antigens of the leprosy bacillus. We report here that M. leprae specific epitopes recognized by all of 13 monoclonal antibodies tested were produced by recombinant phage in Escherichia coli.  相似文献   
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