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   82624篇
  免费   10187篇
  国内免费   609篇
耳鼻咽喉   1165篇
儿科学   2028篇
妇产科学   1818篇
基础医学   9393篇
口腔科学   5270篇
临床医学   11536篇
内科学   17714篇
皮肤病学   2181篇
神经病学   7965篇
特种医学   2095篇
外国民族医学   2篇
外科学   9999篇
综合类   1411篇
现状与发展   2篇
一般理论   14篇
预防医学   8496篇
眼科学   1765篇
药学   5485篇
  6篇
中国医学   668篇
肿瘤学   4407篇
  2023年   1757篇
  2022年   806篇
  2021年   2711篇
  2020年   2488篇
  2019年   2460篇
  2018年   3851篇
  2017年   3241篇
  2016年   3390篇
  2015年   3759篇
  2014年   4624篇
  2013年   5277篇
  2012年   5814篇
  2011年   6218篇
  2010年   4050篇
  2009年   3802篇
  2008年   4482篇
  2007年   4367篇
  2006年   4043篇
  2005年   3637篇
  2004年   3440篇
  2003年   3058篇
  2002年   2821篇
  2001年   1838篇
  2000年   1542篇
  1999年   1312篇
  1998年   651篇
  1997年   567篇
  1996年   558篇
  1995年   489篇
  1994年   369篇
  1993年   312篇
  1992年   567篇
  1991年   530篇
  1990年   449篇
  1989年   425篇
  1988年   378篇
  1987年   325篇
  1986年   298篇
  1985年   299篇
  1984年   238篇
  1983年   182篇
  1982年   119篇
  1981年   122篇
  1980年   118篇
  1979年   167篇
  1978年   136篇
  1975年   109篇
  1974年   116篇
  1973年   107篇
  1971年   110篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
1.
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   
2.
3.
The aim of this safety study in mice was to determine in vivo toxicity and biodistribution potential of a single and multiple doses of L-glutamic acid-g-p(HEMA) polymeric nanoparticles as a drug delivery system. The single dose did not cause any lethal effect, and its acute oral LD50 was >2.000 mg/kg body weight (bw). Multiple doses (25, 50, or 100 mg/kg bw) given over 28 days resulted in no significant differences in body and relative organ weights compared to control. These results are supported by biochemical and histological findings. Moreover, nanoparticle exposure did not result in statistically significant differences in micronucleus counts in bone marrow cells compared to control. Nanoparticle distribution was time-dependent, and they reached the organs and even bone marrow by hour 6, as established by ex vivo imaging with the IVIS® spectrum imaging system. In conclusion, L-glutamic acid-g-p(HEMA) polymeric nanoparticles appear biocompatible and have a potential use as a drug delivery system.KEY WORDS: biocompatibility, blood biochemistry, genotoxicity, histology, in vivo toxicity, micronucleus test, polymers  相似文献   
4.
5.
6.
7.
8.
9.
Clinical Oral Investigations - The objective of this systematic review and meta-analysis (SRM) was to answer the question whether the use of ultrasonic irrigation (UI) results in less postoperative...  相似文献   
10.
Clinical Oral Investigations - The aim of this study was to evaluate the efficacy of supplementary techniques (ultrasonic tip/XP-endo Finisher R) in removing remaining filling materials...  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