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   5614篇
  免费   438篇
  国内免费   13篇
耳鼻咽喉   31篇
儿科学   260篇
妇产科学   219篇
基础医学   720篇
口腔科学   36篇
临床医学   599篇
内科学   1165篇
皮肤病学   100篇
神经病学   614篇
特种医学   109篇
外科学   529篇
综合类   59篇
一般理论   6篇
预防医学   750篇
眼科学   50篇
药学   380篇
中国医学   16篇
肿瘤学   422篇
  2023年   33篇
  2022年   23篇
  2021年   129篇
  2020年   97篇
  2019年   119篇
  2018年   155篇
  2017年   92篇
  2016年   138篇
  2015年   140篇
  2014年   200篇
  2013年   310篇
  2012年   421篇
  2011年   478篇
  2010年   246篇
  2009年   209篇
  2008年   330篇
  2007年   347篇
  2006年   355篇
  2005年   356篇
  2004年   320篇
  2003年   307篇
  2002年   297篇
  2001年   64篇
  2000年   33篇
  1999年   49篇
  1998年   62篇
  1997年   39篇
  1996年   37篇
  1995年   37篇
  1994年   26篇
  1993年   37篇
  1992年   32篇
  1991年   20篇
  1990年   28篇
  1989年   29篇
  1988年   22篇
  1987年   25篇
  1986年   25篇
  1985年   21篇
  1984年   26篇
  1983年   28篇
  1982年   35篇
  1981年   26篇
  1980年   24篇
  1978年   14篇
  1977年   23篇
  1975年   13篇
  1974年   16篇
  1973年   17篇
  1972年   15篇
排序方式: 共有6065条查询结果,搜索用时 484 毫秒
91.
To evaluate perceived pain during repetitive annual endometrial sampling at gynaecologic surveillance in asymptomatic women with Lynch syndrome (LS) over time and in addition to symptomatic women without LS, undergoing single endometrial sampling. In this prospective study, 52 women with LS or first degree relatives who underwent repetitive annual gynaecological surveillance including endometrial sampling of which 33 were evaluated twice or more and 50 symptomatic women without LS who had single endometrial sampling, were included. Pain intensity was registered with VAS scores. Differences in pain intensities between subsequent visits (in LS) and between the two groups were evaluated. The use of painkillers before endometrial sampling was registered. If women with LS decided for preventive surgery, the reason was recorded. The LS group reported a median VAS score of 5.0 (range 0–10) at the first surveillance (n = 52) and at the second visit (n = 24). Women who repeatedly underwent endometrial sampling more often used painkillers for this procedure. During the study period 7/52 (13 %) women with LS choose for preventive surgery, another 4/52 (8 %) refused further endometrial sampling. Painful endometrial sampling was mentioned as main reason to quit screening. The median VAS score of the 50 symptomatic women was 5.0 (range 1–9). Endometrial sampling, irrespective of indication, is a painful procedure, with a median VAS score of 5.0. During subsequent procedures in women with LS, the median pain score does not aggravate although one in five women chose an alternative for endometrial sampling.  相似文献   
92.
93.
94.
Alanine substitutions and selected deletions have been used to localize amino acids in QnrB essential for its protective activity. Essential amino acids are found at positions i and i−2 in the pentapeptide repeat module and in the larger of two loops, where deletion of only a single amino acid compromises activity. Deletion of 10 amino acids at the N terminus is tolerated, but removal of 3 amino acids in the C-terminal dimerization unit destroys activity.  相似文献   
95.
96.
97.
98.
99.
OBJECTIVES: To compare the risk of mortality of nonagenarian siblings with that of sporadic nonagenarians (not selected on having a nonagenarian sibling) and to compare the prevalence of morbidity in their offspring with that of the offsprings' partners.
DESIGN: Longitudinal (mortality risk) and cross-sectional (disease prevalence).
SETTING: Nationwide sample.
PARTICIPANTS: The Leiden Longevity Study consists of 991 nonagenarian siblings derived from 420 Caucasian families, 1,365 of their offspring, and 621 of the offsprings' partners. In the Leiden 85-plus Study, 599 subjects aged 85 were included, of whom 275 attained the age of 90 (sporadic nonagenarians).
MEASUREMENTS: All nonagenarian siblings and sporadic nonagenarians were followed for mortality (with a mean±standard deviation follow-up time of 2.7±1.4 years and 3.0±1.5 years, respectively). Information on medical history and medication use was collected for offspring and their partners.
RESULTS: Nonagenarian siblings had a 41% lower risk of mortality ( P <.001) than sporadic nonagenarians. The offspring of nonagenarian siblings had a lower prevalence of myocardial infarction (2.4% vs 4.1%, P =.03), hypertension (23.0% vs 27.5%, P =.01), diabetes mellitus (4.4% vs 7.6%, P =.004), and use of cardiovascular medication (23.0% vs 28.9%, P =.003) than their partners.
CONCLUSION: The lower mortality rate of nonagenarian siblings and lower prevalence of morbidity in their middle-aged offspring reinforce the notion that resilience against disease and death have similar underlying biology that is determined by genetic or familial factors.  相似文献   
100.
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