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   4769438篇
  免费   359171篇
  国内免费   14606篇
耳鼻咽喉   66470篇
儿科学   151293篇
妇产科学   125809篇
基础医学   720253篇
口腔科学   130904篇
临床医学   434344篇
内科学   862495篇
皮肤病学   117005篇
神经病学   389514篇
特种医学   185662篇
外国民族医学   689篇
外科学   724924篇
综合类   132610篇
现状与发展   23篇
一般理论   2697篇
预防医学   393551篇
眼科学   113302篇
药学   340758篇
  31篇
中国医学   12849篇
肿瘤学   238032篇
  2021年   56482篇
  2019年   58859篇
  2018年   75192篇
  2017年   57597篇
  2016年   63967篇
  2015年   76517篇
  2014年   111048篇
  2013年   176447篇
  2012年   135287篇
  2011年   143341篇
  2010年   129912篇
  2009年   129736篇
  2008年   128925篇
  2007年   138600篇
  2006年   146085篇
  2005年   140947篇
  2004年   140802篇
  2003年   130964篇
  2002年   119914篇
  2001年   183448篇
  2000年   179909篇
  1999年   162844篇
  1998年   73750篇
  1997年   68777篇
  1996年   67017篇
  1995年   62304篇
  1994年   56262篇
  1993年   52231篇
  1992年   118214篇
  1991年   114169篇
  1990年   110467篇
  1989年   107513篇
  1988年   98849篇
  1987年   96976篇
  1986年   91488篇
  1985年   89270篇
  1984年   72976篇
  1983年   64738篇
  1982年   49705篇
  1981年   46192篇
  1980年   43434篇
  1979年   63928篇
  1978年   50609篇
  1977年   44832篇
  1976年   41442篇
  1975年   42550篇
  1974年   46949篇
  1973年   45087篇
  1972年   42406篇
  1971年   39549篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
81.
82.
83.
Caring for patients with end-stage kidney disease (ESKD) in the United States is challenging, due in part to the complex epidemiology of the disease's progression as well as the ways in which care is delivered. As CKD progresses toward ESKD, the number of comorbidities increases and care involves multiple healthcare providers from multiple subspecialties. This occurs in the context of a fragmented US healthcare delivery system that is traditionally siloed by provider specialty, organization, as well as systems of payment and administration. This article describes the role of care fragmentation in the delivery of optimal ESKD care and identifies research gaps in the evidence across the continuum of care. We then consider the impact of care fragmentation on ESKD care from the patient and health system perspectives and explore opportunities for system-level interventions aimed at improving care for patients with ESKD.  相似文献   
84.
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   
85.
86.
87.
88.
89.
90.
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   
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