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   1026839篇
  免费   66746篇
  国内免费   1342篇
耳鼻咽喉   13645篇
儿科学   27643篇
妇产科学   24694篇
基础医学   144276篇
口腔科学   28778篇
临床医学   86455篇
内科学   202448篇
皮肤病学   19661篇
神经病学   81757篇
特种医学   41049篇
外国民族医学   79篇
外科学   168465篇
综合类   18843篇
现状与发展   1篇
一般理论   234篇
预防医学   70360篇
眼科学   22279篇
药学   77545篇
  3篇
中国医学   2167篇
肿瘤学   64545篇
  2018年   19943篇
  2017年   15955篇
  2016年   18442篇
  2015年   9236篇
  2014年   12279篇
  2013年   17753篇
  2012年   27111篇
  2011年   34794篇
  2010年   22581篇
  2009年   20085篇
  2008年   34734篇
  2007年   38241篇
  2006年   26697篇
  2005年   27422篇
  2004年   27027篇
  2003年   27269篇
  2002年   25582篇
  2001年   55014篇
  2000年   57038篇
  1999年   47128篇
  1998年   10920篇
  1997年   9719篇
  1996年   9745篇
  1995年   9086篇
  1994年   8441篇
  1993年   7726篇
  1992年   35619篇
  1991年   34051篇
  1990年   32868篇
  1989年   31992篇
  1988年   29095篇
  1987年   28367篇
  1986年   26393篇
  1985年   25248篇
  1984年   17907篇
  1983年   15210篇
  1982年   7883篇
  1981年   6784篇
  1979年   15881篇
  1978年   10663篇
  1977年   9071篇
  1976年   7944篇
  1975年   8629篇
  1974年   10499篇
  1973年   9868篇
  1972年   9357篇
  1971年   8852篇
  1970年   8450篇
  1969年   7959篇
  1968年   7224篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
Health status of the underschool children from the second health group, which with having some morphofunctional changes, (503 persons) was studied. The key changes were postural, cardiovascular, neuropsychic changes. The lysozyme level in saliva is the informative index related to the health status of underschool children.  相似文献   
993.
994.
The leaf essential oil of Eugenia zuchowskiae from Monteverde, Costa Rica, has been obtained by hydrodistillation and analyzed by GC–MS. The principal constituents of E. zuchowskiae leaf oil were α-pinene (28.3%), β-caryophyllene (13.2%), α-humulene (13.1%), and α-copaene (8.1%). The leaf essential oil of E. zuchowskiae showed pronounced in-vitro cytotoxic activity against MCF-7, MDA-MB-468, and UACC-257 human tumor cell lines. The major components showed cytotoxic activities comparable to doxorubicin (LC50 14–70 μg/ml).  相似文献   
995.
The sum of phenolic compounds was obtained from the leaves of Caucasian endemic plant Rhododendron ungernii (Trautv.) in the amount of 7%. The extract contains flavonoids, catechins, and anthocyanidins, in particular, quercetin, isoquercetin, quercitrin, hyperin, rutin, (+)-catechin, (−)-epicatechin, (+)-gallocatechin, and leucoanthocyanidins. The sum of phenolic compounds from Rhododendron ungernii completely inhibits Herpes simplex virus reproduction in a bioassay. A new medicinal preparation (Rhodopes) in the form of a 5% ointment was created on the basis of this extract and tested under clinical conditions at a dental clinic and three other specialized medical departments. The results showed a high therapeutic efficacy: Rhodopes favorably influenced the state of patients and caused neither mucosa irritation nor allergic and other adverse reactions. Rhodopes has received State Registration and is recommended for the treatment of all forms of herpetic disorders. __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 1, pp. 10–13, January, 2007.  相似文献   
996.
997.
998.
999.
Measurements of transepithelial electrical resistance (TEER), the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) test and monitoring of poly(ethylene glycol) (PEG) transport have been used to study the effects of the non-ionic surfactants Solulan C24 and Solulan 16, either free in solution or as an integral part of niosome bi-layers, on intestinal epithelial cells from man (Caco-2 cell monolayers). The effects on epithelial integrity and on the transport of the hydrophilic drug metformin depend on the concentration of the surfactants. At concentrations above 1% the effect on TEER of the surfactant in niosomal form and free in solution were equivalent whereas cell viability was preserved to a higher concentration of Solulans when the Solulans were present in the niosomal form. It was concluded that the toxic effect of niosomes arises from free surfactant present in the niosome suspension.  相似文献   
1000.
A 37-year-old Italian male developed a myocardial infarct with subsequent ventricular fibrillation. He was defibrillated seven times with up to 360 Joules. Thirteen days later the patient died of recurrent myocardial infarct due to thrombotic occlusion of the left circumflex coronary artery. At autopsy, necrosis of the right pectoralis muscle was observed. Electroporation is the pathogenetic mechanism of skeletal muscle damage due to multiple defibrillations with high energy levels. Received: 8 January 1998 Accepted: 15 April 1998  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