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   62871篇
  免费   5259篇
  国内免费   2404篇
耳鼻咽喉   734篇
儿科学   705篇
妇产科学   1202篇
基础医学   9432篇
口腔科学   1543篇
临床医学   5657篇
内科学   11758篇
皮肤病学   1085篇
神经病学   4403篇
特种医学   2038篇
外国民族医学   12篇
外科学   8381篇
综合类   5755篇
现状与发展   1篇
一般理论   5篇
预防医学   3600篇
眼科学   1662篇
药学   5815篇
  10篇
中国医学   1336篇
肿瘤学   5400篇
  2023年   359篇
  2022年   734篇
  2021年   1110篇
  2020年   787篇
  2019年   973篇
  2018年   1494篇
  2017年   1170篇
  2016年   1209篇
  2015年   1470篇
  2014年   1875篇
  2013年   2075篇
  2012年   2902篇
  2011年   2967篇
  2010年   1740篇
  2009年   1615篇
  2008年   2451篇
  2007年   2453篇
  2006年   2304篇
  2005年   2069篇
  2004年   1735篇
  2003年   1732篇
  2002年   1593篇
  2001年   4877篇
  2000年   4786篇
  1999年   4150篇
  1998年   1557篇
  1997年   1164篇
  1996年   751篇
  1995年   621篇
  1994年   547篇
  1993年   473篇
  1992年   2003篇
  1991年   1756篇
  1990年   1602篇
  1989年   1545篇
  1988年   1348篇
  1987年   1248篇
  1986年   1098篇
  1985年   932篇
  1984年   600篇
  1983年   470篇
  1982年   256篇
  1981年   183篇
  1980年   142篇
  1979年   283篇
  1978年   78篇
  1974年   75篇
  1973年   95篇
  1972年   71篇
  1969年   66篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
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   
3.
Platelet function has been described by many laboratory assays, and PL-11 is a new point-of-care platelet function analyzer based on platelet count drop method, which counts platelet before and after the addition of agonists in the citrated whole blood samples. The present study sought to compare PL-11 with other three major more established assays, light transmission aggregometry (LTA), VerifyNow? aspirin system and thromboelastography (TEG), for monitoring the short-term aspirin responses in healthy individuals. Ten healthy young men took 100?mg/d aspirin for 3-day treatment. Platelet function was measured via PL-11, LTA, VerifyNow and TEG, respectively. The blood samples were collected at baseline, 2 hour, 1 day during the aspirin treatment and 1 day, 5?±?1 days, 8?±?1 days after the aspirin withdrawal. Moreover, 90 additional healthy subjects were recruited to establish a reference range for PL-11. Platelet function of healthy subjects decreased significantly 2 hours after 100?mg/d aspirin intake and began to recover during 4–6 days after the aspirin withdrawal. Correlations between methods were PL-11 vs. LTA (r?=?0.614, p?<?0.01); PL-11 vs. VerifyNow (r?=?0.829, p?<?0.01); PL-11 vs. TEG (r?=?0.697, p?<?0.001). There was no significant bias between PL-11 and LTA at baseline (bias?=?1.94%, p?=?0.804) using Bland-Altman analysis, while the data of PL-11 were significantly higher than LTA (bias?=?24.02%, p?<?0.001) during the aspirin therapy. The reference range for PL-11 in healthy young individuals was from 66.8 to 90.5% (95%CI). When aspirin low-responsiveness was defined as LTA?>?20%, the cut-off values for each method were, respectively: PL-11?>?50%, VerifyNow?>?533 ARU, TEG?>?60.2%. The results of different platelet function assays were uninterchangeable for monitoring aspirin response and correlations among them were also varied. Correlations among PL-11 and other three major assays suggested the ability of PL-11 to assess the treatment effects of aspirin. But a large cohort study is needed to confirm the cut-off value of aspirin response detected by PL-11.  相似文献   
4.
5.
6.
7.
8.
9.
Loss of function variants in NOTCH1 cause left ventricular outflow tract obstructive defects (LVOTO). However, the risk conferred by rare and noncoding variants in NOTCH1 for LVOTO remains largely uncharacterized. In a cohort of 49 families affected by hypoplastic left heart syndrome, a severe form of LVOTO, we discovered predicted loss of function NOTCH1 variants in 6% of individuals. Rare or low-frequency missense variants were found in 16% of families. To make a quantitative estimate of the genetic risk posed by variants in NOTCH1 for LVOTO, we studied associations of 400 coding and noncoding variants in NOTCH1 in 1,085 cases and 332,788 controls from the UK Biobank. Two rare intronic variants in strong linkage disequilibrium displayed significant association with risk for LVOTO amongst European-ancestry individuals. This result was replicated in an independent analysis of 210 cases and 68,762 controls of non-European and mixed ancestry. In conclusion, carrying rare predicted loss of function variants in NOTCH1 confer significant risk for LVOTO. In addition, the two intronic variants seem to be associated with an increased risk for these defects. Our approach demonstrates the utility of population-based data sets in quantifying the specific risk of individual variants for disease-related phenotypes.  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