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   2535620篇
  免费   174332篇
  国内免费   3432篇
耳鼻咽喉   33581篇
儿科学   82617篇
妇产科学   65935篇
基础医学   366445篇
口腔科学   65657篇
临床医学   225772篇
内科学   489877篇
皮肤病学   52768篇
神经病学   202295篇
特种医学   97119篇
外国民族医学   491篇
外科学   384698篇
综合类   50355篇
现状与发展   12篇
一般理论   876篇
预防医学   200821篇
眼科学   57573篇
药学   185919篇
  12篇
中国医学   5260篇
肿瘤学   145301篇
  2021年   19816篇
  2019年   20387篇
  2018年   47072篇
  2017年   36157篇
  2016年   40364篇
  2015年   27310篇
  2014年   38001篇
  2013年   56249篇
  2012年   83261篇
  2011年   100402篇
  2010年   64709篇
  2009年   55920篇
  2008年   93618篇
  2007年   100739篇
  2006年   83056篇
  2005年   81774篇
  2004年   79416篇
  2003年   77537篇
  2002年   73331篇
  2001年   109219篇
  2000年   111966篇
  1999年   93884篇
  1998年   27509篇
  1997年   24081篇
  1996年   24339篇
  1995年   23011篇
  1994年   21151篇
  1993年   19912篇
  1992年   72138篇
  1991年   70251篇
  1990年   68606篇
  1989年   65850篇
  1988年   60451篇
  1987年   59246篇
  1986年   55319篇
  1985年   53128篇
  1984年   39442篇
  1983年   33522篇
  1982年   20005篇
  1979年   35929篇
  1978年   25725篇
  1977年   21283篇
  1976年   20381篇
  1975年   21864篇
  1974年   26202篇
  1973年   24839篇
  1972年   23222篇
  1971年   22047篇
  1970年   20279篇
  1969年   19343篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
43.
ContextIt is especially important that patients are well informed when making high-stakes, preference-sensitive decisions like those on the Physician Orders for Life-Sustaining Treatment (POLST) form. However, there is currently no way to easily evaluate whether patients understand key concepts when making these important decisions.ObjectivesTo develop a POLST knowledge survey.MethodsExpert (n = 62) ratings of key POLST facts were used to select items for a POLST knowledge survey. The survey was administered to nursing facility residents (n = 97) and surrogate decision-makers (n = 112). A subset (n = 135) were re-administered the survey after a standardized advance care planning discussion to assess the scale's responsiveness to change.ResultsThe 19-item survey demonstrated adequate reliability (α = 0.72.). Residents' scores (x = 11.4, standard deviation 3.3) were significantly lower than surrogate scores (x = 14.7, standard deviation 2.5) (P < 0.001). Scores for both groups increased significantly after administration of a standardized advance care planning discussion (P < 0.001). Although being a surrogate, age, race, education, cognitive functioning, and health literacy were significantly associated with higher POLST Knowledge Survey scores in univariate analyses, only being a surrogate (P < 0.001) and being white (P = 0.028) remained significantly associated with higher scores in multivariate analyses.ConclusionThe 19-item POLST Knowledge Survey demonstrated adequate reliability and responsiveness to change. Findings suggest the survey could be used to identify knowledge deficits and provide targeted education to ensure adequate understanding of key clinical decisions when completing POLST.  相似文献   
44.
45.
46.
47.
BackgroundSecond-hand smoking or environmental tobacco smoke is a critical health risk. Children are the most vulnerable to second-hand smoking because of their small bronchial ducts, less developed immunity, and low-physical activity.ObjectivesThe purpose of this study was to ascertain the effects of second-hand smoking on lung functions in athlete and non-athlete school-aged children.MethodsThis observational study included forty-six school-aged children, their age was 8–15 years, assigned to three groups; 2 study groups and 1 control group (n=15). The study groups comprised of 16 football players, and of 15 cyclists. Lung functions were evaluated recording forced vital capacity, forced expiratory volume in 1 sec and peak expiratory flow using digital spirometer.ResultsAll measures were recorded in definite values and the children were also classified into second-hand smoking (SH), or non-exposed to tobacco smoking (NE). The findings presented a significant increase (p<0.05) of the study groups in forced vital capacity, forced expiratory volume in 1 sec and peak expiratory flow solely for the non-exposed children. However, there were non-significant differences between the cyclists and football players or between the passive smoking children and non-exposed children in any of the two study groups (p>0.05).ConclusionThe outcomes of this study suggest beneficial influences of the sports activity on the lung functions, without different influences of the cyclists and football players on the lung functions.  相似文献   
48.
49.
50.
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