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   1075458篇
  免费   71631篇
  国内免费   1367篇
耳鼻咽喉   15018篇
儿科学   34646篇
妇产科学   28631篇
基础医学   153474篇
口腔科学   29571篇
临床医学   94963篇
内科学   203772篇
皮肤病学   24393篇
神经病学   81490篇
特种医学   42971篇
外国民族医学   201篇
外科学   163125篇
综合类   21714篇
现状与发展   1篇
一般理论   264篇
预防医学   74653篇
眼科学   24543篇
药学   86153篇
  7篇
中国医学   2807篇
肿瘤学   66059篇
  2019年   7766篇
  2018年   11307篇
  2017年   8911篇
  2016年   10098篇
  2015年   11264篇
  2014年   15282篇
  2013年   22208篇
  2012年   30568篇
  2011年   32307篇
  2010年   18957篇
  2009年   17826篇
  2008年   29969篇
  2007年   32087篇
  2006年   32720篇
  2005年   31053篇
  2004年   29734篇
  2003年   28557篇
  2002年   27541篇
  2001年   60036篇
  2000年   61496篇
  1999年   50934篇
  1998年   12452篇
  1997年   11004篇
  1996年   11019篇
  1995年   10325篇
  1994年   9344篇
  1993年   8859篇
  1992年   37811篇
  1991年   36290篇
  1990年   35758篇
  1989年   34290篇
  1988年   30868篇
  1987年   30002篇
  1986年   28227篇
  1985年   26461篇
  1984年   19199篇
  1983年   16122篇
  1982年   8834篇
  1979年   17043篇
  1978年   11406篇
  1977年   10231篇
  1976年   8845篇
  1975年   10073篇
  1974年   11655篇
  1973年   11276篇
  1972年   10757篇
  1971年   10096篇
  1970年   9256篇
  1969年   8942篇
  1968年   7923篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
6.
7.
8.
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   
9.
As millions of people turn to social media for health information, better understanding the factors that guide health-related judgments and perceptions in this context is imperative. We report on two Web experiments (n > 400 total) examining the power of society’s widespread weight bias and related stereotypes to influence nutrition judgments in social media spaces. In Experiment 1, meals were judged as lower in nutritional quality when the person who recommended them (the source) was depicted as obese rather than of normal weight, an effect mediated by stereotypic beliefs about the source as a generally unhealthy person. Experiment 2 replicated this effect, which—notably—remained significant when controlling for objective nutritional information (calories and fat content). Results highlight spillover effects of weight bias that extend beyond person perception to color impressions of objects (here, food) that are associated with stigmatized attributes. Implications for everyday nutrition judgments and public health are considered.  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