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   1614773篇
  免费   132683篇
  国内免费   2642篇
耳鼻咽喉   21847篇
儿科学   53394篇
妇产科学   46541篇
基础医学   229403篇
口腔科学   47572篇
临床医学   141859篇
内科学   317619篇
皮肤病学   34588篇
神经病学   130876篇
特种医学   65200篇
外国民族医学   479篇
外科学   246023篇
综合类   39837篇
现状与发展   3篇
一般理论   546篇
预防医学   123857篇
眼科学   36827篇
药学   122343篇
  3篇
中国医学   3057篇
肿瘤学   88224篇
  2018年   15481篇
  2016年   13445篇
  2015年   15487篇
  2014年   21291篇
  2013年   32225篇
  2012年   43570篇
  2011年   45874篇
  2010年   27035篇
  2009年   25935篇
  2008年   43719篇
  2007年   45929篇
  2006年   46679篇
  2005年   45202篇
  2004年   44594篇
  2003年   42505篇
  2002年   41604篇
  2001年   75902篇
  2000年   78556篇
  1999年   66546篇
  1998年   17803篇
  1997年   16395篇
  1996年   16373篇
  1995年   16049篇
  1994年   15105篇
  1993年   14247篇
  1992年   55456篇
  1991年   53798篇
  1990年   52582篇
  1989年   50852篇
  1988年   47242篇
  1987年   46581篇
  1986年   44295篇
  1985年   42865篇
  1984年   32095篇
  1983年   27615篇
  1982年   16175篇
  1981年   14457篇
  1980年   13594篇
  1979年   30491篇
  1978年   21096篇
  1977年   17791篇
  1976年   16718篇
  1975年   17602篇
  1974年   21502篇
  1973年   20687篇
  1972年   18861篇
  1971年   17779篇
  1970年   16292篇
  1969年   15275篇
  1968年   13950篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
22.
23.
24.
25.
26.
27.
28.
29.
On 8 April 2014, a US jury ordered Takeda and Eli Lilly to pay $9 bn in punitive damages after finding that they had concealed the cancer risks associated with pioglitazone. By contrast, on 28 August 2014, the long‐awaited outcome of the 10‐year Kaiser Permanente Northern California study was announced. That study was specifically designed to investigate whether patients exposed to pioglitazone were at an increased risk of bladder cancer and found no association; thus, at last, the controversial issue has been resolved. A review, in retrospect, of the story of the proposed link between pioglitazone and bladder cancer reveals flaws at every stage. In 2012, a BMJ editorial, in keeping with some other contemporary reports, stated ‘it can confidently be assumed that pioglitazone increases the risk of bladder cancer’. Examination of the information which led to such a statement shows that: 1) the pre‐clinical findings of bladder cancer in male rats is not indicative of human risk; 2) there is no association between bladder cancer and pioglitazone in randomized controlled trials, once cases that could not plausibly be related to treatment are removed; and 3) the observational studies that have suggested a link have over‐extrapolated from the data: pioglitazone‐treated patients had more risk factors for bladder cancer than those not treated with pioglitazone. Meanwhile careful study of randomized controlled trials shows evidence of cardiovascular benefit from pioglitazone in Type 2 diabetes, a condition which results, more than anything, in premature cardiovascular death and morbidity.  相似文献   
30.

Objectives

To investigate whether functional overreaching affects locomotor system behaviour when running at fixed relative intensities and if any effects were associated with changes in running performance.

Design

Prospective intervention study.

Methods

Ten trained male runners completed three training blocks in a fixed order. Training consisted of one week of light training (baseline), two weeks of heavy training designed to induce functional overreaching, and ten days of light taper training designed to allow athletes to recover from, and adapt to, the heavy training. Locomotor behaviour, 5-km time trial performance, and subjective reports of training status (Daily Analysis of Life Demands for Athletes (DALDA) questionnaire) were assessed at the completion of each training block. Locomotor behaviour was assessed using detrended fluctuation analysis of stride intervals during running at speeds corresponding to 65% and 85% of maximum heart rate (HRmax) at baseline.

Results

Time trial performance (effect size ±95% confidence interval (ES): 0.16 ± 0.06; p < 0.001), locomotor behaviour at 65% HRmax (ES: ?1.12 ± 0.95; p = 0.026), and DALDA (ES: 2.55 ± 0.80; p < 0.001) were all detrimentally affected by the heavy training. Time trial performance improved relative to baseline after the taper (ES: ?0.16 ± 0.10; p = 0.003) but locomotor behaviour at 65% HRmax (ES: ?1.18 ± 1.17; p = 0.048) and DALDA (ES: 0.92 ± 0.90; p = 0.045) remained impaired.

Conclusions

Locomotor behaviour during running at 65% HRmax was impaired by functional overreaching and remained impaired after a 10-day taper, despite improved running performance. Locomotor changes may increase injury risk and should be considered within athlete monitoring programs independently of performance changes.  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