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   2346393篇
  免费   184901篇
  国内免费   7507篇
耳鼻咽喉   32206篇
儿科学   78862篇
妇产科学   64542篇
基础医学   327166篇
口腔科学   64188篇
临床医学   209790篇
内科学   473212篇
皮肤病学   53490篇
神经病学   189513篇
特种医学   94962篇
外国民族医学   883篇
外科学   363377篇
综合类   53253篇
现状与发展   3篇
一般理论   765篇
预防医学   184182篇
眼科学   51325篇
药学   169233篇
  7篇
中国医学   4195篇
肿瘤学   123647篇
  2018年   23807篇
  2017年   18343篇
  2016年   21306篇
  2015年   23920篇
  2014年   33363篇
  2013年   50579篇
  2012年   65265篇
  2011年   69840篇
  2010年   42762篇
  2009年   41264篇
  2008年   65915篇
  2007年   70607篇
  2006年   71685篇
  2005年   69426篇
  2004年   67036篇
  2003年   65242篇
  2002年   63014篇
  2001年   112639篇
  2000年   116550篇
  1999年   98126篇
  1998年   28539篇
  1997年   25664篇
  1996年   26603篇
  1995年   26184篇
  1994年   24593篇
  1993年   22934篇
  1992年   80050篇
  1991年   78240篇
  1990年   75642篇
  1989年   72267篇
  1988年   66734篇
  1987年   65517篇
  1986年   61523篇
  1985年   59180篇
  1984年   44976篇
  1983年   37905篇
  1982年   22987篇
  1981年   20777篇
  1980年   19168篇
  1979年   40521篇
  1978年   28951篇
  1977年   24560篇
  1976年   22629篇
  1975年   24023篇
  1974年   28223篇
  1973年   27086篇
  1972年   24967篇
  1971年   22970篇
  1970年   21286篇
  1969年   19644篇
排序方式: 共有10000条查询结果,搜索用时 62 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.
Imaging     
  相似文献   
44.
45.
46.
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   
47.
Abstract: Background: Fetal pulse oximetry improves the assessment of fetal well‐being during labor. The objective of this study was to evaluate women's satisfaction with their experience with this additional technology. Methods: We surveyed women participating in the FOREMOST trial, a randomized controlled trial comparing the addition of fetal pulse oximetry (FPO) to conventional cardiotocograph (CTG) monitoring (intervention group), versus CTG‐only (control group), in the presence of nonreassuring fetal status during labor. Our survey evaluated 3 aspects of women's experience: labor, fetal monitoring, and participation in the research. The survey was administered within a few days of giving birth and repeated 3 months later. Results: No differences were found between the intervention and control groups for women's evaluations of their labor, fetal monitoring, research, or overall experiences when surveyed on both occasions. Within each study group, a small but statistically significant decline occurred in women's scores for their experience of labor and overall experience from the initial survey close to the time of giving birth, to 3 months later. The magnitude of differences in responses over time was similar for the both groups. Women were more satisfied after a spontaneous or assisted vaginal birth than after cesarean section. Length of time the research midwife was present had a significant positive effect on women's ratings of their experience several days after giving birth (p = 0.006), but no effect at 3 months. Conclusions: The addition of fetal pulse oximetry for the assessment of fetal well‐being during labor did not affect childbearing women's perceptions of fetal monitoring or their labor. Women evaluated their experience in the research process positively overall. Small changes occurred in women's perception of their satisfaction over time. (BIRTH 33:2 June 2006)  相似文献   
48.
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