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   1816437篇
  免费   146489篇
  国内免费   3452篇
耳鼻咽喉   24045篇
儿科学   58578篇
妇产科学   50356篇
基础医学   256146篇
口腔科学   51336篇
临床医学   162703篇
内科学   359348篇
皮肤病学   36980篇
神经病学   150982篇
特种医学   71844篇
外国民族医学   484篇
外科学   275858篇
综合类   42848篇
现状与发展   3篇
一般理论   837篇
预防医学   141824篇
眼科学   41952篇
药学   135664篇
  9篇
中国医学   3293篇
肿瘤学   101288篇
  2019年   14944篇
  2018年   19741篇
  2017年   15338篇
  2016年   17053篇
  2015年   19880篇
  2014年   27847篇
  2013年   41470篇
  2012年   57643篇
  2011年   60587篇
  2010年   35328篇
  2009年   33340篇
  2008年   56986篇
  2007年   60107篇
  2006年   60633篇
  2005年   59196篇
  2004年   57770篇
  2003年   54929篇
  2002年   53153篇
  2001年   77597篇
  2000年   79814篇
  1999年   68426篇
  1998年   20330篇
  1997年   18491篇
  1996年   18159篇
  1995年   17797篇
  1994年   16624篇
  1993年   15567篇
  1992年   56569篇
  1991年   54827篇
  1990年   53460篇
  1989年   51721篇
  1988年   48096篇
  1987年   47439篇
  1986年   45154篇
  1985年   43714篇
  1984年   33126篇
  1983年   28567篇
  1982年   17335篇
  1981年   15605篇
  1979年   31106篇
  1978年   21740篇
  1977年   18346篇
  1976年   17228篇
  1975年   18007篇
  1974年   21931篇
  1973年   21060篇
  1972年   19194篇
  1971年   18034篇
  1970年   16545篇
  1969年   15457篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
63.
64.
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   
65.
66.
While peer support has been investigated in multiple clinical contexts, its application to the postpartum setting is unknown. The aim was to assess acceptability of a postpartum peer support program for women with diabetes. Observational survey-based needs assessment of forty low-income women with diabetes, receiving care at a major medical institution. Mean age and gravidity were 30.7 years and 3.15 ± 1.67 respectively. 45 % expressed interest in a “buddy.” There was no significant difference between groups desiring and not desiring this program. A majority of respondents desired telephone, text messaging, and in-person contacts (79.2, 72.1, 83.8 %), with 72.5 % of patients desiring diabetes-related activities during clinic waiting time. Many women desire a postpartum diabetes reciprocal peer program for support outside of clinician visits. Patients are receptive to educational services during their wait and outside of clinic time, a potentially valuable opportunity to share important health information.  相似文献   
67.

Background

Obesity is a risk factor for acetabular component malposition when total hip arthroplasty is performed with manual techniques. The utility of imageless navigation in obese patients remains unknown. This study compared the accuracy and precision of imageless navigation for component orientation between obese and nonobese patients.

Methods

A total of 459 total hip arthroplasties performed for osteoarthritis using imageless navigation were reviewed from a single surgeon’s institutional review board–approved database. Einzel-Bild-Roentgen Analyse determined component orientation on 6-week postoperative anteroposterior radiographs. Mean orientation error (accuracy) and precision were compared between obese (body mass index ≥ 30 kg/m2) and nonobese patients. Regression analysis evaluated the influence of obesity on component position.

Results

The difference in mean inclination and anteversion between obese and nonobese groups was 1.1° (43.0° ± 3.5°; range, 35.8°-57.8° vs 41.9° ± 4.4°; range, 33.0°-57.1° and 24.9° ± 6.3°; range, 14.2°-44.3° vs 23.8° ± 6.6°; range, 7.0°-38.6°, respectively). Inclination precision was better for nonobese patients. No difference in inclination accuracy or anteversion accuracy or precision was detected between groups. And 83% of components were placed within the target range. There was no relationship between obesity (dichotomized) and component placement outside the target ranges for inclination, anteversion, or both. As a continuous variable, increased body mass index correlated with higher odds of inclination outside the target zone (odds ratio, 1.06; P = .001).

Conclusion

Using imageless navigation, inclination orientation was less precise for obese patients, but the observed difference is likely not clinically relevant. Accurate superficial registration of landmarks in obese patients is achievable, and the use of imageless navigation similarly improves acetabular component positioning in obese and nonobese patients.

Level of Evidence

Therapeutic Level IV.  相似文献   
68.
69.
70.
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