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   1214594篇
  免费   80376篇
  国内免费   2551篇
耳鼻咽喉   17078篇
儿科学   37194篇
妇产科学   31909篇
基础医学   174030篇
口腔科学   32532篇
临床医学   108334篇
内科学   230259篇
皮肤病学   28170篇
神经病学   92022篇
特种医学   49736篇
外国民族医学   201篇
外科学   181502篇
综合类   23362篇
现状与发展   6篇
一般理论   340篇
预防医学   83314篇
眼科学   28345篇
药学   98170篇
  7篇
中国医学   4241篇
肿瘤学   76769篇
  2021年   12074篇
  2019年   11024篇
  2018年   15235篇
  2017年   11791篇
  2016年   13933篇
  2015年   16457篇
  2014年   21615篇
  2013年   29823篇
  2012年   42048篇
  2011年   43398篇
  2010年   25577篇
  2009年   23369篇
  2008年   38243篇
  2007年   40239篇
  2006年   40167篇
  2005年   38103篇
  2004年   35968篇
  2003年   33958篇
  2002年   32205篇
  2001年   62577篇
  2000年   63883篇
  1999年   52994篇
  1998年   13487篇
  1997年   11808篇
  1996年   11775篇
  1995年   11024篇
  1994年   9957篇
  1993年   9372篇
  1992年   38901篇
  1991年   37335篇
  1990年   36684篇
  1989年   35171篇
  1988年   31651篇
  1987年   30743篇
  1986年   28942篇
  1985年   27108篇
  1984年   19677篇
  1983年   16562篇
  1982年   9134篇
  1979年   17435篇
  1978年   11727篇
  1977年   10547篇
  1976年   9113篇
  1975年   10312篇
  1974年   11947篇
  1973年   11526篇
  1972年   11007篇
  1971年   10276篇
  1970年   9431篇
  1969年   9089篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
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   
22.
23.
24.
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   
25.
26.
27.
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