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   1696978篇
  免费   123770篇
  国内免费   3793篇
耳鼻咽喉   21735篇
儿科学   55656篇
妇产科学   46182篇
基础医学   241481篇
口腔科学   48770篇
临床医学   151406篇
内科学   333848篇
皮肤病学   38690篇
神经病学   131276篇
特种医学   64021篇
外国民族医学   242篇
外科学   257599篇
综合类   38973篇
现状与发展   4篇
一般理论   531篇
预防医学   124279篇
眼科学   40216篇
药学   123709篇
  7篇
中国医学   4476篇
肿瘤学   101440篇
  2021年   12831篇
  2019年   13543篇
  2018年   19977篇
  2017年   15235篇
  2016年   16644篇
  2015年   18990篇
  2014年   26258篇
  2013年   38003篇
  2012年   52811篇
  2011年   55538篇
  2010年   32846篇
  2009年   30750篇
  2008年   51594篇
  2007年   54893篇
  2006年   55353篇
  2005年   52627篇
  2004年   50843篇
  2003年   48242篇
  2002年   46446篇
  2001年   91846篇
  2000年   93665篇
  1999年   77003篇
  1998年   19741篇
  1997年   17292篇
  1996年   17407篇
  1995年   16758篇
  1994年   15301篇
  1993年   14084篇
  1992年   57407篇
  1991年   55290篇
  1990年   52995篇
  1989年   50774篇
  1988年   46151篇
  1987年   44946篇
  1986年   42241篇
  1985年   39997篇
  1984年   29363篇
  1983年   24919篇
  1982年   13905篇
  1979年   25538篇
  1978年   17577篇
  1977年   14908篇
  1976年   13876篇
  1975年   14565篇
  1974年   17632篇
  1973年   16950篇
  1972年   15674篇
  1971年   14457篇
  1970年   13434篇
  1969年   12520篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
Levels of the soluble form of the triggering receptor expressed on myeloid cells (sTREM)-1 are elevated in severe sepsis. However, it is not known whether sTREM-1 measurements can distinguish milder bacterial infections from noninfectious inflammation. The present authors studied whether serum sTREM-1 levels differ in community-acquired pneumonia, exacerbations of chronic obstructive pulmonary disease (COPD), asthma and controls, and whether sTREM-1 may be used as a surrogate marker for the need for antibiotics. Serum sTREM-1 levels in 150 patients with pneumonia, COPD and asthma exacerbations and 62 healthy controls were measured. Serum sTREM-1 levels were significantly elevated in pneumonia (median 295.2 ng x mL(-1)), COPD (280.3 ng x mL(-1)) and asthma exacerbations (184.0 ng x mL(-1)) compared with controls (83.1 ng x mL(-1)). Levels were higher in pneumonia and Anthonisen type 1 COPD exacerbations than in type 2 and 3 COPD and asthma exacerbations. The area under the receiver operating characteristics curve for sTREM-1 as a surrogate marker for the need for antibiotics was 0.77. Serum levels of the soluble form of the triggering receptor expressed on myeloid cells-1 were elevated predominantly in pneumonia and Anthonisen type 1 COPD exacerbations versus type 2 and 3 chronic obstructive pulmonary disease exacerbations, asthma and controls. Serum levels of the soluble form of the triggering receptor expressed on myeloid cells-1 has moderate but insufficient accuracy as a surrogate marker for the need for antibiotics in lower respiratory tract infections.  相似文献   
32.
33.
The precise molecular cause of insulin resistance has not yet been elucidated. Resistance to the normal action of insulin contributes to the pathogenesis of a number of common human disorders, including type 1 (insulin-dependent) and type 2 (non-insulin-dependent) diabetes mellitus, hypertension, and the Metabolic Syndrome X, thus constituting a major public health problem. A disease program aimed at combating this disorder should focus on the identification of targets for therapeutic intervention which may overcome insulin resistance and hence the associated metabolic consequences characteristic of the Metabolic Syndrome. Although the primary defect in the pathogenesis of type 2 diabetes is unknown, genetic and environmental factors are likely to contribute to the manifestation of this progressive metabolic disorder, which is usually not clinically apparent until mid-life. Defects at the level of glucose uptake/phosphorylation characterize insulin resistance in skeletal muscle of type 2 diabetic patients. Identification of putative components of the insulin receptor-signaling pathway may offer insights into mechanisms involved in insulin resistance. Enhanced flux of free fatty acids due to impaired lipid metabolism may contribute to impaired insulin secretion and peripheral insulin resistance. Genes regulating lipolysis are prime candidates for susceptibility towards the metabolic syndrome. Here we describe pathways constituting complex interactions that control glucose homeostasis. We will be considering (1) regulation of glucose uptake by the insulin receptor signaling pathway, and (2) control of adipogenesis and insulin sensitivity by the sterol response element binding protein (SREBP) pathway.  相似文献   
34.
35.
36.
Infections due to Penicillium species other than P.marneffei are rare. We identified a boy with X-linked chronic granulomatous disease (X-CGD) with a pulmonary nodule and adjacent rib osteomyelitis caused by Penicillium piceum. The only sign of infection was an elevated sedimentation rate. P. piceum was isolated by fine needle aspirate and from excised infected tissues. Surgical removal and one year of voriconazole treatment were very well tolerated and led to complete recovery. Microbiological, microscopic and molecular studies support the fungal diagnosis. P. piceum should be considered as a relevant pathogen in immunocompromised patients.  相似文献   
37.
38.
39.
40.
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