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   983424篇
  免费   113426篇
  国内免费   574篇
  1097424篇
  2018年   8406篇
  2016年   11333篇
  2015年   15775篇
  2014年   18437篇
  2013年   25951篇
  2012年   28882篇
  2011年   29058篇
  2010年   19314篇
  2009年   18214篇
  2008年   25886篇
  2007年   26783篇
  2006年   25421篇
  2005年   24831篇
  2004年   24553篇
  2003年   23616篇
  2002年   22624篇
  2001年   43132篇
  2000年   43610篇
  1999年   34682篇
  1998年   12267篇
  1997年   12887篇
  1996年   12336篇
  1995年   11563篇
  1994年   11419篇
  1993年   11447篇
  1992年   29560篇
  1991年   29214篇
  1990年   28340篇
  1989年   27751篇
  1988年   25899篇
  1987年   24723篇
  1986年   22903篇
  1985年   23145篇
  1984年   19234篇
  1983年   16641篇
  1982年   12740篇
  1981年   11771篇
  1980年   11157篇
  1979年   18649篇
  1978年   14506篇
  1977年   13452篇
  1976年   12488篇
  1975年   13998篇
  1974年   14883篇
  1973年   14674篇
  1972年   13400篇
  1971年   12085篇
  1970年   10690篇
  1969年   10247篇
  1968年   9366篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
71.
72.
73.
74.
Over the past 10 years the AIDS crisis has produced a large volume of writing. Much of this is documentary. Dozens of studies of AIDS from various clinical and political perspectives have been complemented by just as many published diaries, autobiographies, novels, plays, and poems. A few of these works have risen to the surface not only as extraordinarily valuable testimonies to the changes AIDS has wrought in individual and collective life but also as first-rate literary works, worth reading because beyond their immediate purposes they articulate with extraordinary lucidity and compassion some deep truths about the human--and the modern--condition. Paul Monette's Borrowed Time is among the most distinctive of those. It speaks not only for the community of people with AIDS and those who support them but for a generation.  相似文献   
75.
76.
77.
Trigger finger is a relatively common clinical entity, most frequently caused by stenosing tenosynovitis. Several other conditions not related to tenosynovitis also have been described as a cause of triggering, and these have been reviewed. We present a rare anomaly of the fourth lumbrical muscle insertion as a cause of triggering of the right little finger. This was completely relieved following excision of the anomalous muscle. This rare anatomic variant should be added to the list of potential causes of trigger finger.  相似文献   
78.
79.
80.
Isopropanol administered in a large (6 g/kg, orally) as well as in a lower dose (1 g/kg, I.P.) is slowly oxidized into acetone by the intact rat. Using two inhibitors, 3 amino-1,2,4-triazole and pyrazole, investigations on the hepatic enzymatic system involved in the oxidation of isopropanol show that catalase does not play an important part in this pathway, contrary to alcohol dehydrogenase which is the major enzyme responsible for this oxidation. Although isopropanol oxidation is mainly catalysed in the liver through alcohol dehydrogenase, no alteration of the hepatic extramitochondrial redox state occurs after the administration of a large as well as of a lower dose of isopropanol. From these experiments it may be concluded that alterations of the liver NAD+/NADH ratio, which seem to play an important part in the ethanol induced fatty liver, are not involved in the isopropanol induced one.  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