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   4344876篇
  免费   352888篇
  国内免费   15502篇
耳鼻咽喉   61747篇
儿科学   134565篇
妇产科学   113031篇
基础医学   663183篇
口腔科学   120169篇
临床医学   394046篇
内科学   787763篇
皮肤病学   104208篇
神经病学   371431篇
特种医学   173167篇
外国民族医学   912篇
外科学   661438篇
综合类   127079篇
现状与发展   23篇
一般理论   2700篇
预防医学   368232篇
眼科学   102105篇
药学   306929篇
  25篇
中国医学   11540篇
肿瘤学   208973篇
  2021年   56430篇
  2020年   35894篇
  2019年   59106篇
  2018年   74034篇
  2017年   56562篇
  2016年   62975篇
  2015年   76297篇
  2014年   111249篇
  2013年   176918篇
  2012年   122950篇
  2011年   126803篇
  2010年   124813篇
  2009年   127357篇
  2008年   113290篇
  2007年   120446篇
  2006年   129450篇
  2005年   124769篇
  2004年   125446篇
  2003年   115943篇
  2002年   106352篇
  2001年   154655篇
  2000年   150766篇
  1999年   139874篇
  1998年   71548篇
  1997年   67923篇
  1996年   65811篇
  1995年   61616篇
  1994年   55696篇
  1993年   51721篇
  1992年   103728篇
  1991年   99115篇
  1990年   94237篇
  1989年   91835篇
  1988年   85431篇
  1987年   83903篇
  1986年   79608篇
  1985年   78085篇
  1984年   66094篇
  1983年   58963篇
  1982年   48236篇
  1981年   44975篇
  1980年   42252篇
  1979年   57963篇
  1978年   47115篇
  1977年   41665篇
  1976年   38722篇
  1975年   37941篇
  1974年   42530篇
  1973年   40657篇
  1972年   38111篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
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   
82.
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   
83.
84.
85.
86.
87.
88.
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   
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