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   216508篇
  免费   12897篇
  国内免费   591篇
耳鼻咽喉   2858篇
儿科学   6677篇
妇产科学   4755篇
基础医学   29653篇
口腔科学   9741篇
临床医学   16443篇
内科学   48502篇
皮肤病学   5569篇
神经病学   18623篇
特种医学   6394篇
外国民族医学   26篇
外科学   26339篇
综合类   1683篇
现状与发展   1篇
一般理论   73篇
预防医学   22041篇
眼科学   4070篇
药学   13793篇
中国医学   951篇
肿瘤学   11804篇
  2023年   1235篇
  2022年   2714篇
  2021年   5047篇
  2020年   3248篇
  2019年   4767篇
  2018年   6394篇
  2017年   4686篇
  2016年   4542篇
  2015年   5311篇
  2014年   7214篇
  2013年   9198篇
  2012年   14155篇
  2011年   14812篇
  2010年   7670篇
  2009年   6716篇
  2008年   11500篇
  2007年   12064篇
  2006年   11107篇
  2005年   11284篇
  2004年   10693篇
  2003年   9624篇
  2002年   7576篇
  2001年   5906篇
  2000年   5883篇
  1999年   5083篇
  1998年   1850篇
  1997年   1504篇
  1996年   1492篇
  1995年   1233篇
  1994年   1226篇
  1993年   1098篇
  1992年   2957篇
  1991年   2860篇
  1990年   2624篇
  1989年   2549篇
  1988年   2320篇
  1987年   2148篇
  1986年   2012篇
  1985年   1919篇
  1984年   1414篇
  1983年   1138篇
  1982年   649篇
  1981年   605篇
  1980年   573篇
  1979年   1026篇
  1978年   687篇
  1977年   528篇
  1975年   605篇
  1974年   602篇
  1973年   591篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
2.
3.
4.
Post-induction hypotension is common and associated with postoperative complications. We hypothesised that pneumatic leg compression reduces post-induction hypotension in elderly patients undergoing robot-assisted laparoscopic prostatectomy. In this double-blind randomised study, patients were allocated randomly to the pneumatic leg compression group (n = 50) or control (n = 50). In the intervention group, pneumatic leg compression was initiated before induction of anaesthesia. In the control group, pneumatic leg compression was initiated 20 min after anaesthesia induction. The primary outcome was the incidence of post-induction hypotension in these groups. Post-induction hypotension was defined as systolic blood pressure < 90 mmHg during the first 20 min after induction. Haemodynamic variables and area under the curve of post-induction systolic blood pressure over time were assessed. Complications associated with pneumatic leg compression were recorded, including: peripheral neuropathy; compartment syndrome; extensive bullae beneath the leg sleeves; and pulmonary thromboembolism. The incidence of post-induction hypotension decreased in the pneumatic leg compression group compared with that in the control group; 5 (10%) vs. 29 (58%), respectively, p < 0.001. In the pneumatic leg compression group, the lowest systolic, diastolic and mean blood pressures 20 min after induction of anaesthesia were significantly greater than the control group. Pneumatic leg compression resulted in an increased area under the curve of systolic blood pressure in the first 20 min after induction, p = 0.001. There were no pneumatic leg compression-related complications. Pneumatic leg compression reduced post-induction hypotension in elderly patients undergoing robot-assisted laparoscopic prostatectomy, suggesting that it is an effective and safe intervention to prevent post-induction hypotension among elderly patients undergoing general anaesthesia.  相似文献   
5.
6.
7.
Neorickettsia helminthoeca (NH), the agent of salmon poisoning disease or canine neorickettiosis (CN), is a bacterial endosymbiont of the nematode Nanophyetus salmincola, and infections are spreading among specific fish‐eating mammalians. This article describes the pathologic and immunohistochemical findings associated with spontaneous NH‐induced infections in dogs from Southern Brazil. The principal pathologic findings were hypertrophy of Peyer patches and lymphadenopathy with lymphocytic proliferation, chronic interstitial pneumonia, and chronic enteritis associated with positive intralesional immunoreactivity to antigens of NH within macrophages and histiocytes. Positive immunoreactivity against canine parvovirus‐2 (CPV‐2) or/and canine distemper virus was not detected in the evaluated intestinal segments or in the samples from the cerebellum and lungs, respectively, from the dogs evaluated. These findings demonstrated that NH was involved in the enteric, pulmonary, and lymphoid lesions herein described, and provide additional information to confirm the occurrence of this bacterial endosymbiont within this geographical location. It is proposed that chronic pneumonia should be considered as a pathologic manifestation of NH‐induced infections. Additionally, our results show that the occurrences of CN seem to be underdiagnosed in Southern Brazil due to the confusion with the incidence of CPV‐2.  相似文献   
8.
9.
10.
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