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   375014篇
  免费   34852篇
  国内免费   26040篇
耳鼻咽喉   2845篇
儿科学   4895篇
妇产科学   4195篇
基础医学   41089篇
口腔科学   6134篇
临床医学   52953篇
内科学   50771篇
皮肤病学   4140篇
神经病学   18179篇
特种医学   13791篇
外国民族医学   224篇
外科学   33113篇
综合类   70098篇
现状与发展   86篇
一般理论   31篇
预防医学   27654篇
眼科学   10676篇
药学   40767篇
  432篇
中国医学   24427篇
肿瘤学   29406篇
  2024年   1274篇
  2023年   5462篇
  2022年   14414篇
  2021年   18294篇
  2020年   14418篇
  2019年   11694篇
  2018年   12176篇
  2017年   11684篇
  2016年   10786篇
  2015年   16849篇
  2014年   20973篇
  2013年   19099篇
  2012年   28438篇
  2011年   31959篇
  2010年   21561篇
  2009年   17546篇
  2008年   21443篇
  2007年   21164篇
  2006年   20181篇
  2005年   19261篇
  2004年   12725篇
  2003年   12243篇
  2002年   10016篇
  2001年   8537篇
  2000年   8327篇
  1999年   8394篇
  1998年   5300篇
  1997年   5093篇
  1996年   3958篇
  1995年   3714篇
  1994年   3134篇
  1993年   2026篇
  1992年   2426篇
  1991年   2126篇
  1990年   1792篇
  1989年   1556篇
  1988年   1283篇
  1987年   1183篇
  1986年   955篇
  1985年   676篇
  1984年   369篇
  1983年   271篇
  1982年   142篇
  1981年   169篇
  1980年   115篇
  1979年   154篇
  1978年   73篇
  1977年   53篇
  1974年   42篇
  1972年   37篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
The present study compared the level of occupational strain and work ability among Han, Hui, Uygur, Hui, and Kazakh teachers, and explored ethnic differences based on the associations of psychosocial factors at work, occupational strain, and work ability. A cross-sectional survey was conducted among 2,941 teachers in primary and secondary schools in Xinjiang Province, China. Psychosocial factors, occupational strain, and work ability were measured using the Occupation Stress Inventory—Revised Edition (OSI-R) and Work Ability Index. Han and Hui teachers experienced reduced work ability compared with Uygur and Kazakh teachers, and this finding was caused, in part, by exposure to psychosocial factors at work. The vocational and psychological strains caused by these factors play an important role in reduced work ability among all ethnic teacher groups. The findings indicate the importance of taking action to reduce occupational strain for promoting teachers' work ability in multiethnic workplaces.  相似文献   
12.
13.
14.
15.
16.
目的探讨指压天枢穴加腹部按摩联合番泻叶在静脉肾盂造影患者中的应用效果。方法选取我院2018年12月至2019年8月期间行静脉肾盂造影的120例患者,随机分为两组各60例。对照组给予番泻叶,观察组给予天枢穴指压加腹部按摩联合番泻叶,比较两组的肠道清洁力度和不良反应情况。结果治疗后,观察组的肠道清洁力度明显高于对照组(P <0.05);观察组的不良反应发生率为6.67%,明显低于对照组的23.33%(P <0.05)。结论静脉肾盂造影患者采用指压天枢穴加腹部按摩联合番泻叶的效果较好,可提高肠道清洁力度,降低不良反应发生率。  相似文献   
17.
手术治疗精索静脉曲张在改善精液质量、提高配偶自然怀孕率和缓解局部疼痛症状中的作用已为多数医生所认同。随着手术方式的改进,越来越多的精索静脉曲张患者接受手术治疗,然而,临床对手术后患者的管理还重视不够。本文系统介绍了对精索静脉曲张手术后患者的疗效判断和后续治疗选择,包括观察随诊、非手术治疗方法和再手术。  相似文献   
18.
19.
Based on the physical randomization of completely randomized experiments, in a recent article in Statistics in Medicine, Rigdon and Hudgens propose two approaches to obtaining exact confidence intervals for the average causal effect on a binary outcome. They construct the first confidence interval by combining, with the Bonferroni adjustment, the prediction sets for treatment effects among treatment and control groups, and the second one by inverting a series of randomization tests. With sample size n, their second approach requires performing O(n4)randomization tests. We demonstrate that the physical randomization also justifies other ways to constructing exact confidence intervals that are more computationally efficient. By exploiting recent advances in hypergeometric confidence intervals and the stochastic order information of randomization tests, we propose approaches that either do not need to invoke Monte Carlo or require performing at most O(n2)randomization tests. We provide technical details and R code in the Supporting Information . Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
20.
Oral cancer, predominantly oral squamous cell carcinoma (OSCC), is one of the most leading causes of cancers worldwide. Due to a low 5-year survival rate, highly effective methods for the early detection of OSCC are totally needed. MicroRNAs (miRNAs), as promising biomarkers, can bring insights into tumorigenesis of oral cancers. However, studies on the accuracy of miRNAs detection in OSCC have inconsistent conclusions, leading us to conduct this meta-analysis. The aim of this study was to systematically review the articles investigating the diagnostic value of miRNAs in OSCC.The PubMed, Embase, Chinese National Knowledge Infrastructure (CNKI), Web of Science were searched (updated to June 11th, 2015) to identify all articles evaluating the diagnostic yield of miRNAs for OSCC. The pooled sensitivity, specificity, and other diagnostic parameters were used to assess the performance of miRNAs assays on OSCC detection. Statistical analysis was conducted by employing the R software.The present meta-analysis comprised 23 studies from 10 articles, including 598 OSCC patients and 320 healthy individuals, available for analysis. The summary receiver operator characteristic (SROC) curve was plotted. Meanwhile, the pooled diagnostic parameters and the area under curve (AUC) were calculated based on all included studies. The pooled diagnostic parameters calculated from all 23 studies were as follows: pooled sensitivity of 0.759 (95% CI: 0.701–0.809), pooled specificity of 0.773 (95% CI: 0.713–0.823) and AUC of 0.832, which indicates a relatively high diagnostic accuracy of miRNAs in differentiating OSCC patients from healthy controls. Meanwhile, In addition, subgroup analyses were conducted to access the heterogeneity between studies, which is based on specimen (serum/plasma/blood/saliva/ tissue) and ethnicity (Asian/Caucasian).In summary, our meta-analysis suggests that miRNAs might be used in noninvasive screening tests for OSCC, which needs further large-scale studies to be validated.  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