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   1332054篇
  免费   95615篇
  国内免费   21813篇
耳鼻咽喉   16991篇
儿科学   36863篇
妇产科学   31562篇
基础医学   184935篇
口腔科学   33706篇
临床医学   132156篇
内科学   240768篇
皮肤病学   26674篇
神经病学   95873篇
特种医学   52332篇
外国民族医学   399篇
外科学   187414篇
综合类   65521篇
现状与发展   75篇
一般理论   286篇
预防医学   90158篇
眼科学   32589篇
药学   113716篇
  306篇
中国医学   18367篇
肿瘤学   88791篇
  2022年   14570篇
  2021年   21468篇
  2020年   15483篇
  2019年   16927篇
  2018年   20762篇
  2017年   17292篇
  2016年   18015篇
  2015年   23221篇
  2014年   29946篇
  2013年   34488篇
  2012年   48783篇
  2011年   53407篇
  2010年   31780篇
  2009年   27702篇
  2008年   42958篇
  2007年   45075篇
  2006年   45961篇
  2005年   44614篇
  2004年   37724篇
  2003年   35966篇
  2002年   33729篇
  2001年   65274篇
  2000年   67466篇
  1999年   57763篇
  1998年   17099篇
  1997年   15704篇
  1996年   14647篇
  1995年   13796篇
  1994年   12195篇
  1993年   10782篇
  1992年   39898篇
  1991年   38045篇
  1990年   37244篇
  1989年   35536篇
  1988年   31944篇
  1987年   30919篇
  1986年   28929篇
  1985年   27016篇
  1984年   19517篇
  1983年   16310篇
  1979年   17115篇
  1978年   11404篇
  1977年   10229篇
  1975年   10068篇
  1974年   11651篇
  1973年   11273篇
  1972年   10754篇
  1971年   10092篇
  1970年   9252篇
  1969年   8938篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
21.
Severe tuberculosis (TB) requiring intensive care unit (ICU) care is rare but commonly known to be of markedly bad prognosis. The present study aimed to describe this condition and to determine the mortality rate and risk factors associated with mortality. Patients with confirmed TB admitted to ICU between 1990 and 2001 were retrospectively identified and enrolled. Clinical, radiological and bacteriological data at admission and during hospital stay were recorded. A multivariate analysis was performed to identify the predictive factors for mortality. A total of 58 TB patients (12 females, mean age 48 yrs) admitted to ICU were included. Mean Acute Physiology and Chronic Health Evaluation (APACHE) II score at admission was 13.1+/-5.6 and 22 of 58 (37.9%) patients required mechanical ventilation. The in-hospital mortality was 15 of 58 (25.9%); 13 (22.4%) patients died in the ICU. The mean survival of patients who died was 53.6 days (range 1-229), with 50% of the patients dying within the first 32 days. The factors independently associated with mortality were: acute renal failure, need for mechanical ventilation, chronic pancreatitis, sepsis, acute respiratory distress syndrome, and nosocomial pneumonia. These data indicate a high mortality of patients with tuberculosis requiring intensive care unit care and identifies new independently associated risk factors.  相似文献   
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