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   2083077篇
  免费   161098篇
  国内免费   4759篇
耳鼻咽喉   28560篇
儿科学   68055篇
妇产科学   59486篇
基础医学   296092篇
口腔科学   57584篇
临床医学   183659篇
内科学   414771篇
皮肤病学   47193篇
神经病学   170359篇
特种医学   80582篇
外国民族医学   772篇
外科学   317158篇
综合类   47759篇
现状与发展   3篇
一般理论   706篇
预防医学   161257篇
眼科学   47569篇
药学   147787篇
  1篇
中国医学   4640篇
肿瘤学   114941篇
  2019年   16508篇
  2018年   23179篇
  2017年   17872篇
  2016年   19721篇
  2015年   22259篇
  2014年   31679篇
  2013年   47645篇
  2012年   64391篇
  2011年   68473篇
  2010年   40546篇
  2009年   38607篇
  2008年   63698篇
  2007年   67467篇
  2006年   68028篇
  2005年   66314篇
  2004年   63473篇
  2003年   60764篇
  2002年   59019篇
  2001年   100394篇
  2000年   102932篇
  1999年   86188篇
  1998年   24194篇
  1997年   22004篇
  1996年   22014篇
  1995年   20670篇
  1994年   19034篇
  1993年   17919篇
  1992年   65707篇
  1991年   62756篇
  1990年   60761篇
  1989年   58086篇
  1988年   53609篇
  1987年   52488篇
  1986年   49553篇
  1985年   47280篇
  1984年   35807篇
  1983年   30399篇
  1982年   18388篇
  1981年   16214篇
  1979年   32179篇
  1978年   22631篇
  1977年   18911篇
  1976年   17909篇
  1975年   18981篇
  1974年   22834篇
  1973年   21980篇
  1972年   20637篇
  1971年   18904篇
  1970年   18090篇
  1969年   16871篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
Behçet disease is a complex, multisystem disease characterized by recurrent oral and genital ulcerations. It rarely occurs in infants or children. Neonatal Behçet disease has been reported in infants whose ulcers resolve at or before 9 weeks of age. Few cases of neonatal Behçet disease persisting into childhood have previously been reported. We report the case of a 1‐month‐old infant who presented with severe recurrent genital ulcerations and at 6 months developed recurrent oral ulcerations. Her orogenital ulcerations continue to recur. Human leukocyte antigen testing revealed HLA‐B51 and B44 positivity. This is a case of pediatric Behçet disease in the neonatal period. Behçet disease should be considered in the differential diagnosis of recurrent genital and oral ulcerations in infants and children.  相似文献   
73.
74.
AimsWe previously showed that the protective effects of endothelial progenitor cells (EPCs)‐released exosomes (EPC‐EXs) on endothelium in diabetes. However, whether EPC‐EXs are protective in diabetic ischemic stroke is unknown. Here, we investigated the effects of EPC‐EXs on diabetic stroke mice and tested whether miR‐126 enriched EPC‐EXs (EPC‐EXsmiR126) have enhanced efficacy.MethodsThe db/db mice subjected to ischemic stroke were intravenously administrated with EPC‐EXs 2 hours after ischemic stroke. The infarct volume, cerebral microvascular density (MVD), cerebral blood flow (CBF), neurological function, angiogenesis and neurogenesis, and levels of cleaved caspase‐3, miR‐126, and VEGFR2 were measured on day 2 and 14.ResultsWe found that (a) injected EPC‐EXs merged with brain endothelial cells, neurons, astrocytes, and microglia in the peri‐infarct area; (b) EPC‐EXsmiR126 were more effective than EPC‐EXs in decreasing infarct size and increasing CBF and MVD, and in promoting angiogenesis and neurogenesis as well as neurological functional recovery; (c) These effects were accompanied with downregulated cleaved caspase‐3 on day 2 and vascular endothelial growth factor receptor 2 (VEGFR2) upregulation till day 14.ConclusionOur results indicate that enrichment of miR126 enhanced the therapeutic efficacy of EPC‐EXs on diabetic ischemic stroke by attenuating acute injury and promoting neurological function recovery.  相似文献   
75.
76.

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   
77.
78.
79.
80.
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