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   2687694篇
  免费   204684篇
  国内免费   8507篇
耳鼻咽喉   34831篇
儿科学   88147篇
妇产科学   72937篇
基础医学   375106篇
口腔科学   76177篇
临床医学   243109篇
内科学   534658篇
皮肤病学   62517篇
神经病学   214080篇
特种医学   104918篇
外国民族医学   504篇
外科学   412595篇
综合类   63731篇
现状与发展   6篇
一般理论   902篇
预防医学   207698篇
眼科学   61451篇
药学   193349篇
  11篇
中国医学   5919篇
肿瘤学   148239篇
  2018年   29293篇
  2017年   22480篇
  2016年   25589篇
  2015年   29006篇
  2014年   40426篇
  2013年   60050篇
  2012年   78831篇
  2011年   83875篇
  2010年   50879篇
  2009年   48299篇
  2008年   77928篇
  2007年   83032篇
  2006年   84311篇
  2005年   80999篇
  2004年   77888篇
  2003年   74766篇
  2002年   71628篇
  2001年   134521篇
  2000年   138112篇
  1999年   114590篇
  1998年   32177篇
  1997年   28360篇
  1996年   29103篇
  1995年   28622篇
  1994年   26484篇
  1993年   24658篇
  1992年   90607篇
  1991年   87845篇
  1990年   84709篇
  1989年   81201篇
  1988年   74599篇
  1987年   73220篇
  1986年   68994篇
  1985年   65938篇
  1984年   49454篇
  1983年   41766篇
  1982年   24737篇
  1981年   22195篇
  1980年   20552篇
  1979年   43996篇
  1978年   31147篇
  1977年   26528篇
  1976年   24564篇
  1975年   25737篇
  1974年   30669篇
  1973年   29536篇
  1972年   27436篇
  1971年   25258篇
  1970年   23314篇
  1969年   21869篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
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   
42.
43.
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   
44.
45.
46.
Imaging     
  相似文献   
47.
48.
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   
49.
50.
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