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   13515篇
  免费   883篇
  国内免费   28篇
耳鼻咽喉   143篇
儿科学   454篇
妇产科学   351篇
基础医学   2019篇
口腔科学   461篇
临床医学   1346篇
内科学   2574篇
皮肤病学   399篇
神经病学   1398篇
特种医学   469篇
外科学   1693篇
综合类   105篇
一般理论   21篇
预防医学   1052篇
眼科学   150篇
药学   797篇
中国医学   17篇
肿瘤学   977篇
  2023年   115篇
  2022年   174篇
  2021年   398篇
  2020年   277篇
  2019年   338篇
  2018年   363篇
  2017年   308篇
  2016年   338篇
  2015年   342篇
  2014年   455篇
  2013年   594篇
  2012年   913篇
  2011年   871篇
  2010年   463篇
  2009年   468篇
  2008年   721篇
  2007年   726篇
  2006年   657篇
  2005年   645篇
  2004年   548篇
  2003年   507篇
  2002年   517篇
  2001年   289篇
  2000年   241篇
  1999年   221篇
  1998年   115篇
  1997年   89篇
  1996年   86篇
  1995年   71篇
  1994年   74篇
  1993年   72篇
  1992年   126篇
  1991年   106篇
  1990年   109篇
  1989年   114篇
  1988年   107篇
  1987年   124篇
  1986年   109篇
  1985年   97篇
  1984年   82篇
  1983年   78篇
  1982年   60篇
  1981年   54篇
  1978年   58篇
  1977年   54篇
  1976年   63篇
  1973年   56篇
  1969年   55篇
  1968年   48篇
  1966年   52篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
Collagens are the most abundant proteins in the extracellular matrix. They provide a framework to build organs and tissues and give structural support to make them resistant to mechanical load and forces. Several intra‐ and extracellular modifications are needed to make functional collagen molecules, intracellular post‐translational modifications of proline and lysine residues having key roles in this. In this article, we provide a review on the enzymes responsible for the proline and lysine modifications, that is collagen prolyl 4‐hydroxylases, 3‐hydroxylases and lysyl hydroxylases, and discuss their biological functions and involvement in diseases.  相似文献   
2.

Objective

To examine whether a healthy weight intervention embedded in the Parents as Teachers (PAT) home visiting program, which was previously found to improve mothers’ body mass index (BMI) and obesity-related behaviors, changed the BMI of preschool children or maternal feeding practices.

Methods

This stratified randomized trial included preschool-aged children at risk for overweight whose mothers were overweight or had obesity (n?=?179). The Healthy Eating and Active Living Taught at Home (HEALTH) intervention was based on the Diabetes Prevention Program. Differences were examined using repeated-measures mixed-ANOVA models.

Results

Compared with PAT usual care, the HEALTH intervention had no effect on children's BMI or maternal feeding practices. However, combined analyses showed that children's BMI percentile decreased (P??=?.007), BMI z-scores were maintained (P??=?.19), and 3 of 8 feeding practices improved over time (P < .05).

Conclusions and Implications

Additional research is needed to assess the effectiveness of PAT to prevent preschool-age obesity using rigorous designs (eg, group-randomized trials) and to identify its active components. HEALTH is ready to be scaled up to prevent maternal weight gain through embedding within the national PAT program.  相似文献   
3.
4.
5.
6.
7.
8.
9.
The objectives of this study were to systematically review and meta-analyze the research literature on the association of common neurological disorders and violence. Keywords relating to neurological disorders and violence were searched between 1966 and August 2008. Case–control and cohort studies were selected. Odds ratios of violence risk in particular disorders compared with controls were combined using fixed-effects meta-analysis with the data presented in forest plots. Sensitivity analyses were conducted to identify possible differences in risk estimates across surveys. Information on risk factors for violence was extracted if replicated in more than one study. Nine studies were identified that compared the risk of violence in epilepsy or traumatic brain injury compared with unaffected controls. For the epilepsy studies, the overall pooled odds ratio for violent outcomes was 0.67 [95% confidence interval (CI) 0.46–0.96]. For traumatic brain injury, the odds ratio was 1.66 (95% CI 1.12–2.31). An additional 11 case–control studies investigated factors associated with violence in epilepsy and traumatic brain injury. It was not possible to meta-analyze these data. Comorbid psychopathology was associated with violence. Data on other neurological conditions was limited and unreplicated. In conclusion, although the evidence was limited and methodological quality varied, epilepsy and traumatic brain injury appeared to differ in their risk of violence compared with control populations. Longitudinal studies are required to replicate this review’s provisional findings that epilepsy is inversely associated with violence and that brain injury modestly increases the risk, and further research is needed to provide information on a broader range of risk factors.  相似文献   
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