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   1251773篇
  免费   102603篇
  国内免费   3730篇
耳鼻咽喉   19961篇
儿科学   40576篇
妇产科学   31568篇
基础医学   161084篇
口腔科学   32187篇
临床医学   123819篇
内科学   254902篇
皮肤病学   32143篇
神经病学   98733篇
特种医学   50453篇
外国民族医学   201篇
外科学   206580篇
综合类   22137篇
现状与发展   72篇
一般理论   286篇
预防医学   84165篇
眼科学   28097篇
药学   89629篇
  7篇
中国医学   2862篇
肿瘤学   78644篇
  2021年   10864篇
  2020年   10983篇
  2019年   10357篇
  2018年   19125篇
  2017年   16681篇
  2016年   18828篇
  2015年   19884篇
  2014年   30741篇
  2013年   38806篇
  2012年   38268篇
  2011年   40105篇
  2010年   30053篇
  2009年   32178篇
  2008年   37801篇
  2007年   38282篇
  2006年   41080篇
  2005年   36720篇
  2004年   34466篇
  2003年   32293篇
  2002年   31344篇
  2001年   64296篇
  2000年   65072篇
  1999年   54440篇
  1998年   16143篇
  1997年   14518篇
  1996年   14362篇
  1995年   13554篇
  1994年   11358篇
  1993年   10495篇
  1992年   39236篇
  1991年   37769篇
  1990年   36898篇
  1989年   35537篇
  1988年   31978篇
  1987年   30933篇
  1986年   29199篇
  1985年   27336篇
  1984年   19881篇
  1983年   16756篇
  1982年   9450篇
  1979年   17430篇
  1978年   11820篇
  1977年   10703篇
  1976年   9135篇
  1975年   10401篇
  1974年   11918篇
  1973年   11551篇
  1972年   11077篇
  1971年   10315篇
  1970年   9521篇
排序方式: 共有10000条查询结果,搜索用时 12 毫秒
21.
22.
23.
Although studies have documented underuse of controller medications and overuse of short-acting inhaled ss(2)-agonist among children with persistent asthma in disadvantaged communities, the persistence of oral ss(2)-agonist use in pediatric practice has not been studied since inhaled short-acting ss(2)-agonists became widespread. We describe medications used to treat asthma among children 3 to 5 years of age at 10 Head Start and other subsidized preschool centers in East and Central Harlem, New York City. We interviewed 149 parents/guardians of children who were identified as having probable asthma based on physician's diagnosis, persistent symptoms, hospitalization, and medication use. We classified 86 of the 149 children (58%) as having current persistent asthma. Only 15 of them (17%) were reported to have used controller medications at least 5 days/week in the last 4 weeks-only 2 of whom used inhaled corticosteroids. By contrast, 53 children (62%) used oral ss(2)-agonist in the last 4 weeks, often (72%) in conjunction with nebulized or inhaled short-acting ss(2)-agonist. Use of oral ss(2)-agonist was associated with more severe symptoms. This study documents the continued widespread use of oral ss(2)-agonist for treatment of children in a low-income community with high prevalence of asthma.  相似文献   
24.
25.
26.
27.
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   
28.
29.
30.
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