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   2294110篇
  免费   171802篇
  国内免费   4493篇
耳鼻咽喉   31362篇
儿科学   75127篇
妇产科学   64570篇
基础医学   325125篇
口腔科学   63317篇
临床医学   205445篇
内科学   448180篇
皮肤病学   53160篇
神经病学   183409篇
特种医学   88863篇
外国民族医学   665篇
外科学   345284篇
综合类   50165篇
现状与发展   3篇
一般理论   721篇
预防医学   172602篇
眼科学   52673篇
药学   170939篇
  9篇
中国医学   5556篇
肿瘤学   133230篇
  2021年   17304篇
  2019年   18063篇
  2018年   25618篇
  2017年   19753篇
  2016年   22372篇
  2015年   24979篇
  2014年   34942篇
  2013年   51602篇
  2012年   70211篇
  2011年   74392篇
  2010年   43898篇
  2009年   41542篇
  2008年   68786篇
  2007年   72947篇
  2006年   73934篇
  2005年   71116篇
  2004年   67968篇
  2003年   65086篇
  2002年   62853篇
  2001年   118358篇
  2000年   121466篇
  1999年   101180篇
  1998年   27092篇
  1997年   24215篇
  1996年   24286篇
  1995年   22925篇
  1994年   20905篇
  1993年   19680篇
  1992年   76231篇
  1991年   73041篇
  1990年   70849篇
  1989年   67800篇
  1988年   61941篇
  1987年   60267篇
  1986年   56610篇
  1985年   53598篇
  1984年   39974篇
  1983年   33708篇
  1982年   19651篇
  1979年   35330篇
  1978年   24394篇
  1977年   21006篇
  1976年   19069篇
  1975年   20501篇
  1974年   24308篇
  1973年   23442篇
  1972年   22225篇
  1971年   20476篇
  1970年   19184篇
  1969年   18143篇
排序方式: 共有10000条查询结果,搜索用时 546 毫秒
81.
82.

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   
83.
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   
84.
85.
86.
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   
87.
88.
89.
90.
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