首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   197篇
  免费   1篇
  198篇
  2022年   1篇
  2021年   1篇
  2020年   1篇
  2018年   5篇
  2017年   5篇
  2016年   1篇
  2015年   4篇
  2014年   1篇
  2013年   4篇
  2012年   4篇
  2011年   5篇
  2010年   1篇
  2009年   8篇
  2008年   9篇
  2007年   5篇
  2006年   4篇
  2005年   5篇
  2004年   6篇
  2003年   11篇
  2002年   13篇
  2001年   12篇
  2000年   2篇
  1999年   3篇
  1998年   2篇
  1995年   1篇
  1992年   3篇
  1991年   4篇
  1990年   7篇
  1989年   4篇
  1988年   7篇
  1987年   7篇
  1986年   3篇
  1985年   4篇
  1984年   2篇
  1983年   3篇
  1982年   1篇
  1980年   2篇
  1979年   2篇
  1978年   2篇
  1977年   4篇
  1976年   1篇
  1975年   3篇
  1974年   2篇
  1973年   5篇
  1972年   7篇
  1971年   2篇
  1970年   2篇
  1968年   3篇
  1967年   2篇
  1965年   2篇
排序方式: 共有198条查询结果,搜索用时 0 毫秒
21.
No less than 4-fold increase in the antibody titres to Pseudomonas aeruginosa during the infectious process served as laboratory confirmation of its participation in the infectious process. In 49 of 91 patients hemagglutining titre exceeded the diagnostic one (1:640). In 9 patients (chiefly in infants) hemagglutinin titre remained low, but there was a rise of antibody level to Pseudomonas aeruginosa during the disease. High hemagglutinin titres were noted in 12 patients on admission to the clinic, with reduction of the antibody titres at the late periods of the disease. Antibody titres remained unchanged during the disease in 15 patients. In 3 cases the indirect hemagglutination test was assesed as negative. In the rest of the patients hemagglutinin titres varied within the range of the diagnostic titre. Thus, the indirect hemagglutination test with erythrocytic diagnostic agent permitting to determine antibodies to Pseudomonas aeruginosa could be used at the clinic in combination with bacteriological and other investigations for establishing etiology of the destructive process.  相似文献   
22.
23.
24.
The first results of the study of chromatographic and spectral properties of the detected lowmolecular-weight activators, putative emitters in the luminescent reaction of Siberian enchytraeid Henlea sp., are presented.  相似文献   
25.
26.
27.
This is the first study to obtain a high-purity luciferase from the fungus Neonothopanus nambi biomass that is suitable for subsequent sequencing.  相似文献   
28.
The structure of fungal oxyluciferin was determined, the enzymatic bioluminescence reaction under substrate saturation conditions with discrete monitoring of formed products was conducted, and the structures of the end products of the reaction were established. On the basis of these studies, the scheme of oxyluciferin degradation to the end products was developed. The structure of fungal oxyluciferin was confirmed by counter synthesis.  相似文献   
29.
The specific and tightly controlled transport of numerous nutrients and metabolites across cellular membranes is crucial to all forms of life. However, many of the transporter proteins involved have yet to be identified, including the vitamin transporters in various human pathogens, whose growth depends strictly on vitamin uptake. Comparative analysis of the ever-growing collection of microbial genomes coupled with experimental validation enables the discovery of such transporters. Here, we used this approach to discover an abundant class of vitamin transporters in prokaryotes with an unprecedented architecture. These transporters have energy-coupling modules comprised of a conserved transmembrane protein and two nucleotide binding proteins similar to those of ATP binding cassette (ABC) transporters, but unlike ABC transporters, they use small integral membrane proteins to capture specific substrates. We identified 21 families of these substrate capture proteins, each with a different specificity predicted by genome context analyses. Roughly half of the substrate capture proteins (335 cases) have a dedicated energizing module, but in 459 cases distributed among almost 100 gram-positive bacteria, including numerous human pathogens, different and unrelated substrate capture proteins share the same energy-coupling module. The shared use of energy-coupling modules was experimentally confirmed for folate, thiamine, and riboflavin transporters. We propose the name energy-coupling factor transporters for the new class of membrane transporters.  相似文献   
30.
The study analyzed new information regarding the way in which present day Russians (living in Moscow or Tula) perceive societal risks. The main concerns of Russians in year 2003 were essentially the same ones that were identified in previous studies conducted on Western samples: violence, sex, and addiction-type hazards received the highest risk ratings. Women's mean risk judgments were systematically higher than men's mean judgments, and older participants' mean judgments were higher than younger participants' mean judgments regarding domestic hazards. Technically trained people perceived higher societal risk than people with training in the humanities, but the difference between people with technical training and people trained in the humanities was more accentuated among younger people than among the elderly. Also, men living in Tula perceived themselves as less exposed to risks of violence than women living in Tula and both men and women living in Moscow.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号