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   10777篇
  免费   1034篇
  国内免费   1篇
  2023年   66篇
  2022年   132篇
  2021年   316篇
  2020年   156篇
  2019年   205篇
  2018年   269篇
  2017年   231篇
  2016年   370篇
  2015年   590篇
  2014年   636篇
  2013年   792篇
  2012年   848篇
  2011年   911篇
  2010年   544篇
  2009年   432篇
  2008年   646篇
  2007年   631篇
  2006年   517篇
  2005年   480篇
  2004年   460篇
  2003年   378篇
  2002年   336篇
  2001年   124篇
  2000年   108篇
  1999年   107篇
  1998年   81篇
  1997年   79篇
  1996年   70篇
  1995年   72篇
  1994年   52篇
  1993年   45篇
  1992年   52篇
  1991年   68篇
  1990年   68篇
  1989年   54篇
  1988年   53篇
  1987年   51篇
  1986年   60篇
  1985年   50篇
  1984年   66篇
  1983年   48篇
  1982年   34篇
  1981年   36篇
  1978年   25篇
  1977年   30篇
  1976年   26篇
  1975年   28篇
  1974年   24篇
  1972年   24篇
  1970年   23篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
A radioimmunoassay for low molecular weight (LMW) human Kininogen has been carried out. The first step was to prepare LMW Kininogen from human plasma. The proposed method allowed to get chemically pure and biologically active LMW Kininogen. This preparation was used to induce antibody. Optimal conditions for labelling and incubation were determined. This method may be applied to the assay of Kininogen in human plasma.  相似文献   
12.
13.
Cardiolipin (CL) is responsible for modulation of activities of various enzymes involved in oxidative phosphorylation. Although energy production decreases in heart failure (HF), regulation of cardiolipin during HF development is unknown. Enzymes involved in cardiac cardiolipin synthesis and remodeling were studied in spontaneously hypertensive HF (SHHF) rats, explanted hearts from human HF patients, and nonfailing Sprague Dawley (SD) rats. The biosynthetic enzymes cytidinediphosphatediacylglycerol synthetase (CDS), phosphatidylglycerolphosphate synthase (PGPS) and cardiolipin synthase (CLS) were investigated. Mitochondrial CDS activity and CDS-1 mRNA increased in HF whereas CDS-2 mRNA in SHHF and humans, not in SD rats, decreased. PGPS activity, but not mRNA, increased in SHHF. CLS activity and mRNA decreased in SHHF, but mRNA was not significantly altered in humans. Cardiolipin remodeling enzymes, monolysocardiolipin acyltransferase (MLCL AT) and tafazzin, showed variable changes during HF. MLCL AT activity increased in SHHF. Tafazzin mRNA decreased in SHHF and human HF, but not in SD rats. The gene expression of acyl-CoA: lysocardiolipin acyltransferase-1, an endoplasmic reticulum MLCL AT, remained unaltered in SHHF rats. The results provide mechanisms whereby both cardiolipin biosynthesis and remodeling are altered during HF. Increases in CDS-1, PGPS, and MLCL AT suggest compensatory mechanisms during the development of HF. Human and SD data imply that similar trends may occur in human HF, but not during nonpathological aging, consistent with previous cardiolipin studies.  相似文献   
14.
15.
16.
17.
Ultraviolet light irradiation of bacterial spores in the presence of hydrogen peroxide has been shown to produce synergistic kills when compared with ultraviolet light (u.v.) and hydrogen peroxide used sequentially. This use in combination has been patented for the commercial sterilization of packaging before filling with UHT-processed products. Previous results have shown that lamps producing u.v. light with a maximum output at about 254 nm were extremely effective. Results obtained using a Synchrotron radiation source to produce a narrow band of irradiation now shows that the greatest kill of spores of Bacillus subtilis in the presence of hydrogen peroxide is obtained with radiation at ˜270 nm. Such results suggest that the action of the u.v. light is not directly on the spore DNA but may be related to the production of free hydroxyl radicals from hydrogen peroxide.  相似文献   
18.
J. E. Adam 《CMAJ》1968,99(13):660-666
  相似文献   
19.
20.
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