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   1438084篇
  免费   117189篇
  国内免费   3464篇
耳鼻咽喉   18760篇
儿科学   47087篇
妇产科学   41586篇
基础医学   204724篇
口腔科学   38821篇
临床医学   128272篇
内科学   291253篇
皮肤病学   34102篇
神经病学   119044篇
特种医学   55005篇
外国民族医学   464篇
外科学   215505篇
综合类   32957篇
现状与发展   3篇
一般理论   489篇
预防医学   110806篇
眼科学   31932篇
药学   100546篇
  1篇
中国医学   3387篇
肿瘤学   83993篇
  2021年   11423篇
  2019年   12062篇
  2018年   17138篇
  2017年   13073篇
  2016年   14706篇
  2015年   16535篇
  2014年   23258篇
  2013年   34165篇
  2012年   46595篇
  2011年   49228篇
  2010年   28885篇
  2009年   27727篇
  2008年   45510篇
  2007年   48081篇
  2006年   48679篇
  2005年   47185篇
  2004年   45027篇
  2003年   42922篇
  2002年   41431篇
  2001年   74115篇
  2000年   75790篇
  1999年   62667篇
  1998年   17363篇
  1997年   15690篇
  1996年   15858篇
  1995年   15044篇
  1994年   13624篇
  1993年   12795篇
  1992年   46557篇
  1991年   44184篇
  1990年   42134篇
  1989年   40209篇
  1988年   36814篇
  1987年   35970篇
  1986年   33500篇
  1985年   31843篇
  1984年   24237篇
  1983年   20358篇
  1982年   12367篇
  1981年   10925篇
  1979年   21024篇
  1978年   14799篇
  1977年   12276篇
  1976年   11476篇
  1975年   11808篇
  1974年   14205篇
  1973年   13736篇
  1972年   12822篇
  1971年   11667篇
  1970年   11105篇
排序方式: 共有10000条查询结果,搜索用时 703 毫秒
51.
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   
52.
53.
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   
54.
55.

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   
56.
57.
58.
59.
60.
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