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   48503篇
  免费   4450篇
  国内免费   83篇
耳鼻咽喉   621篇
儿科学   1341篇
妇产科学   1419篇
基础医学   6919篇
口腔科学   1292篇
临床医学   5939篇
内科学   8531篇
皮肤病学   639篇
神经病学   3804篇
特种医学   2191篇
外国民族医学   1篇
外科学   6256篇
综合类   992篇
一般理论   23篇
预防医学   5334篇
眼科学   1096篇
药学   3620篇
  3篇
中国医学   130篇
肿瘤学   2885篇
  2021年   664篇
  2019年   641篇
  2018年   755篇
  2017年   640篇
  2016年   619篇
  2015年   732篇
  2014年   976篇
  2013年   1499篇
  2012年   2180篇
  2011年   2259篇
  2010年   1238篇
  2009年   1021篇
  2008年   1899篇
  2007年   2040篇
  2006年   2038篇
  2005年   2015篇
  2004年   1834篇
  2003年   1678篇
  2002年   1708篇
  2001年   1617篇
  2000年   1713篇
  1999年   1456篇
  1998年   660篇
  1997年   542篇
  1996年   541篇
  1995年   549篇
  1994年   481篇
  1993年   470篇
  1992年   1267篇
  1991年   1174篇
  1990年   1158篇
  1989年   1093篇
  1988年   1009篇
  1987年   1017篇
  1986年   933篇
  1985年   921篇
  1984年   724篇
  1983年   638篇
  1982年   451篇
  1981年   408篇
  1980年   412篇
  1979年   659篇
  1978年   525篇
  1977年   418篇
  1976年   405篇
  1975年   380篇
  1974年   454篇
  1973年   440篇
  1972年   451篇
  1971年   426篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
Obsessive-compulsive disorder is increasingly recognized in patients of different age groups. Serotonergic agents, such as clomipramine, have been recently found to be useful in the management of this condition. However, unexpected side effects, such as dysphoria, aggressiveness, and paranoid ideation, may occur with therapeutic doses of this compound, as evidenced in the cases of two male adolescents presented here. Possible pathogenetic factors, involving serotonin and serotonin-receptor abnormalities are discussed. Management of these side effects is based on adequate dose reduction and monitorization.  相似文献   
13.
14.
15.
Young children's ability to participate in conversation has been of particular interest in the study of pragmatic aspects of language. In this study, topics of conversation were investigated by videotaping 10 dyads of 4-year-old children during play. Ten-minute samples were analyzed according to a number of topic-dependent measures. Results revealed that all dyads evidenced some lengthy topics (13-91 utterances). Longer topics were characterized by three text-level functions. Enacting Scenarios, Describing, and Problem Solving. Nevertheless, three fourths of all dialogues were considered relatively short. Generally, partners contributed equally to dialogue, but in some dyads, 1 child dominated initiation. Findings of the study suggest that 4-year-olds are capable of extended participation in dialogue, at least part of the time. Naturalistic play settings may elicit samples of conversation that are representative of preschoolers' ability.  相似文献   
16.
A new technetium-chelating agent based on a triamide monomercaptide tetradentate set of donor groups, mercaptoacetylglycylglycylglycine (MAG3), was synthesized and evaluated. Chelation with 99mTc resulted in a single radiochemical product as expected. Studies in mice of [99mTc]MAG3 indicated excretion rates faster than omicron-iodohippurate (OIH) both in normal and in probenecid treated animals. Specificity for renal excretion was essentially complete. Clearance studies in rats resulted in 2.84 ml/min/100 g for [99mTc]MAG3, 2.17 for OIH, and 1.29 for [125I]iothalamate. Extraction efficiencies were 85% for [99mTc]MAG3, 69% for OIH and 39% for [125I]iothalamate. Probenicid depressed the clearance both of [99mTc]MAG3 and OIH at 25 and 50 mg/kg/hr, but to a greater extent with [99mTc]MAG3. The greater effect is offset, however, by the larger fraction secreted by the renal tubular cells. The animal results suggest that [99mTc]MAG3 may be a useful alternative to [131I]OIH.  相似文献   
17.
Arterial complications of total knee replacement. The Australian experience   总被引:1,自引:0,他引:1  
Arterial complications occurring in association with knee replacement surgery are rare, even though most patients having this operation are elderly and therefore more likely to have peripheral vascular disease. We report a patient who developed an arterial complication during the course of a knee replacement operation, as well as the results of a survey of Fellows of the Australian Orthopaedic Association. Recommendations to minimise this serious complication are proposed.  相似文献   
18.
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