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   748篇
  免费   90篇
  2022年   5篇
  2021年   7篇
  2020年   7篇
  2019年   12篇
  2018年   13篇
  2017年   10篇
  2016年   22篇
  2015年   23篇
  2014年   29篇
  2013年   33篇
  2012年   54篇
  2011年   32篇
  2010年   31篇
  2009年   27篇
  2008年   41篇
  2007年   30篇
  2006年   37篇
  2005年   20篇
  2004年   40篇
  2003年   25篇
  2002年   21篇
  2001年   38篇
  2000年   22篇
  1999年   14篇
  1998年   11篇
  1997年   7篇
  1993年   8篇
  1992年   11篇
  1991年   12篇
  1990年   18篇
  1989年   14篇
  1988年   16篇
  1987年   14篇
  1986年   13篇
  1985年   10篇
  1984年   9篇
  1983年   6篇
  1982年   10篇
  1981年   6篇
  1980年   4篇
  1979年   9篇
  1978年   4篇
  1977年   9篇
  1976年   6篇
  1974年   6篇
  1970年   6篇
  1969年   4篇
  1968年   4篇
  1967年   5篇
  1966年   4篇
排序方式: 共有838条查询结果,搜索用时 15 毫秒
831.
832.
Seven lowlander soldiers who had 1st to 3rd degree of frostbite and 8 lowlander soldiers who recovered from high altitude pulmonary oedema were tested for cold pressor response at 260 m, 26°C, 6.8°C and 4,085 m, 26°C, 6.8°C. 8 lowlander soldiers (Control subjects) of comparable age group were tested for their cold pressor response at 260 m, 26°C and 3,300 m, 26°C. Another group of control subjects from the laboratory were also tested at 2,121 m, 26°C. There was a highly significant decrease in cold pressor response of the frostbite subjects at 260 m, 26°C and a very significant increase at 260 m, 6.8°C as compared to non-frostbite subjects. The subjects who recovered from high altitude pulmonary oedema did not show significant differences as compared with the control subjects. The results suggest certain basic physiological differences in regulation of supply of blood to the extremities under condition of general and local cold exposure.  相似文献   
833.
Several HindIII monomer units of a tandemly repeated nuclear DNA sequence ofBrassica campestris andBrassica juncea (Cruciferae) have been cloned and sequenced. The monomer units, of 177 bp length, are AT-rich and share 88% homology between themselves and more than 65% homology with similar repeats of otherCruciferae likeBrassica oleracea, Sinapis alba andRaphanus sativus. Thus unlike the rapid divergence of tandemly repeated satellite DNA in other organisms, this DNA element is highly conserved thus indicating its importance.  相似文献   
834.
835.
Abstract: Our studies of bovine brain neutral glycosphingolipids (Ngsls) have revealed the presence of several short-chain (containing -CHO 1–4) and previously uncharacterized long-chain (−CHO > 4–5) Ngsls. We reported the structural characterization of brain GgOse4Cer (GA1) and have now purified another brain Ngsl to homogeneity. The purified Ngsl migrated close to standard GgOse4Cer and nLcOse5Cer on a TLC plate employing two different solvent systems. The carbohydrate molar composition indicated the presence of Gal/Glc/GalNAc in a ratio of 2.8:1.0:0.9. Five permethylated alditol acetate peaks were characterized as 2,3,4,6-OMe4Gal, 2,4,6-OMe3Gal, 2,3,6-OMe3Gal, 2,3,6-OMe3Glc, and 4,6-OMe2GalNAcMe by gas chromatography-mass spectrometry. The anomeric carbohydrate sequence has been determined by specific exoglycosidase digestion. Six-hundred megahertz 1H NMR spectroscopy of the oligosaccharide released by ceramide glycanase hydrolysis confirmed the structure of the Ngsl as Galβ1-3GalNAcβ1-3Galα1-4Galβ1-4Glc\1-1Cer or IV3GalGbOse4Cer. Using the immunooverlay technique with anti-stage-specific embryonic antigen 3 antibody, it was found in bovine, rat, and normal adult human brain and bovine myelin, but not in human or rat myelin.  相似文献   
836.
J Anthony  M C Vaidya  A Dasgupta 《Cytobios》1979,26(102):109-112
Gross changes of myelinated fibres and Schwann cells at different degenerative stages were present in all five ENL nerve lesions. Besides these changes, infiltrating cells mainly macrophages, deposition of excessive collagen and perineurial vessel damage were also observed.  相似文献   
837.
838.
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