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   1781324篇
  免费   129153篇
  国内免费   4154篇
耳鼻咽喉   23423篇
儿科学   58948篇
妇产科学   50613篇
基础医学   251018篇
口腔科学   47892篇
临床医学   156576篇
内科学   356425篇
皮肤病学   42265篇
神经病学   145794篇
特种医学   69501篇
外国民族医学   631篇
外科学   261791篇
综合类   34745篇
现状与发展   3篇
一般理论   570篇
预防医学   143818篇
眼科学   39594篇
药学   125423篇
  3篇
中国医学   4074篇
肿瘤学   101524篇
  2021年   14158篇
  2019年   15247篇
  2018年   25957篇
  2017年   20237篇
  2016年   21221篇
  2015年   24558篇
  2014年   31047篇
  2013年   44517篇
  2012年   68062篇
  2011年   66614篇
  2010年   37280篇
  2009年   35822篇
  2008年   58939篇
  2007年   62986篇
  2006年   62835篇
  2005年   68217篇
  2004年   66803篇
  2003年   59913篇
  2002年   53628篇
  2001年   80139篇
  2000年   79893篇
  1999年   69478篇
  1998年   18432篇
  1997年   16512篇
  1996年   16670篇
  1995年   15798篇
  1994年   14311篇
  1993年   13391篇
  1992年   53490篇
  1991年   51234篇
  1990年   49467篇
  1989年   47131篇
  1988年   43341篇
  1987年   42284篇
  1986年   39522篇
  1985年   37285篇
  1984年   28185篇
  1983年   23577篇
  1982年   13807篇
  1979年   25126篇
  1978年   17455篇
  1977年   14403篇
  1976年   13343篇
  1975年   14592篇
  1974年   17702篇
  1973年   16893篇
  1972年   15935篇
  1971年   14729篇
  1970年   13967篇
  1969年   13096篇
排序方式: 共有10000条查询结果,搜索用时 296 毫秒
71.
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   
72.
73.
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   
74.
75.

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   
76.
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