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   3271340篇
  免费   246812篇
  国内免费   5704篇
耳鼻咽喉   45013篇
儿科学   106922篇
妇产科学   90233篇
基础医学   476819篇
口腔科学   90303篇
临床医学   298869篇
内科学   631545篇
皮肤病学   73349篇
神经病学   262692篇
特种医学   122786篇
外国民族医学   905篇
外科学   490586篇
综合类   72493篇
现状与发展   15篇
一般理论   1228篇
预防医学   259703篇
眼科学   76598篇
药学   240371篇
  12篇
中国医学   6893篇
肿瘤学   176521篇
  2021年   26063篇
  2019年   26877篇
  2018年   37248篇
  2017年   28062篇
  2016年   31674篇
  2015年   35565篇
  2014年   50484篇
  2013年   75884篇
  2012年   103859篇
  2011年   110907篇
  2010年   65646篇
  2009年   62098篇
  2008年   103210篇
  2007年   109870篇
  2006年   110972篇
  2005年   107632篇
  2004年   103245篇
  2003年   98978篇
  2002年   95662篇
  2001年   150897篇
  2000年   154694篇
  1999年   129735篇
  1998年   38040篇
  1997年   33692篇
  1996年   33725篇
  1995年   31857篇
  1994年   29392篇
  1993年   27602篇
  1992年   99872篇
  1991年   97056篇
  1990年   94316篇
  1989年   90917篇
  1988年   83680篇
  1987年   81768篇
  1986年   76686篇
  1985年   73609篇
  1984年   55323篇
  1983年   47006篇
  1982年   28316篇
  1979年   50466篇
  1978年   35856篇
  1977年   29873篇
  1976年   28507篇
  1975年   30224篇
  1974年   36502篇
  1973年   34777篇
  1972年   32743篇
  1971年   30660篇
  1970年   28511篇
  1969年   26975篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
122.
Nevo  N.  Goldstein  A. L.  Staierman  M.  Eran  N.  Carmeli  I.  Rayman  S.  mnouskin  Y. 《Hernia》2022,26(6):1491-1499
Hernia - The minimally invasive surgical repair of combined inguinal and ventral hernias often requires shifting from one approach or plane to another. The traditional enhanced-view totally...  相似文献   
123.

Researchers have highlighted numerous sociocultural factors that have been shown to underpin human appearance enhancement practices, including the influence of peers, family, the media, and sexual objectification. Fewer scholars have approached appearance enhancement from an evolutionary perspective or considered how sociocultural factors interact with evolved psychology to produce appearance enhancement behavior. Following others, we argue that evidence from the field of evolutionary psychology can complement existing sociocultural models by yielding unique insight into the historical and cross-cultural ubiquity of competition over aspects of physical appearance to embody what is desired by potential mates. An evolutionary lens can help to make sense of reliable sex and individual differences that impact appearance enhancement, as well as the context-dependent nature of putative adaptations that function to increase physical attractiveness. In the current review, appearance enhancement is described as a self-promotion strategy used to enhance reproductive success by rendering oneself more attractive than rivals to mates, thereby increasing one’s mate value. The varied ways in which humans enhance their appearance are described, as well as the divergent tactics used by women and men to augment their appearance, which correspond to the preferences of opposite-sex mates in a heterosexual context. Evolutionarily relevant individual differences and contextual factors that vary predictably with appearance enhancement behavior are also discussed. The complementarity of sociocultural and evolutionary perspectives is emphasized and recommended avenues for future interdisciplinary research are provided for scholars interested in studying appearance enhancement behavior.

  相似文献   
124.
125.
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   
126.
127.
128.
129.
130.
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