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   556篇
  免费   30篇
  国内免费   5篇
耳鼻咽喉   6篇
儿科学   17篇
妇产科学   4篇
基础医学   36篇
口腔科学   23篇
临床医学   56篇
内科学   104篇
皮肤病学   17篇
神经病学   8篇
特种医学   70篇
外科学   131篇
综合类   6篇
预防医学   41篇
眼科学   3篇
药学   32篇
中国医学   1篇
肿瘤学   36篇
  2021年   7篇
  2019年   3篇
  2018年   13篇
  2017年   8篇
  2016年   7篇
  2015年   8篇
  2014年   18篇
  2013年   14篇
  2012年   29篇
  2011年   20篇
  2010年   16篇
  2009年   13篇
  2008年   22篇
  2007年   20篇
  2006年   22篇
  2005年   22篇
  2004年   19篇
  2003年   18篇
  2002年   22篇
  2001年   17篇
  2000年   16篇
  1999年   20篇
  1998年   8篇
  1997年   12篇
  1996年   14篇
  1995年   13篇
  1994年   17篇
  1993年   16篇
  1992年   6篇
  1991年   8篇
  1990年   11篇
  1989年   18篇
  1988年   16篇
  1987年   12篇
  1985年   6篇
  1984年   3篇
  1983年   7篇
  1982年   7篇
  1980年   3篇
  1979年   4篇
  1978年   3篇
  1976年   8篇
  1972年   3篇
  1969年   3篇
  1968年   3篇
  1967年   6篇
  1966年   2篇
  1945年   2篇
  1933年   2篇
  1932年   2篇
排序方式: 共有591条查询结果,搜索用时 15 毫秒
21.
Hypersensitivity pneumonitis: evaluation with CT   总被引:4,自引:0,他引:4  
Silver  SF; Muller  NL; Miller  RR; Lefcoe  MS 《Radiology》1989,173(2):441-445
Thirteen chest radiographs and computed tomographic (CT) scans obtained from 11 patients with hypersensitivity pneumonitis were reviewed. The CT findings were correlated with open lung biopsy findings in seven patients. The two patients with acute hypersensitivity pneumonitis showed air-space opacification on CT scans. An open lung biopsy, done in one of these patients, demonstrated noncaseating granulomas and filling of the air spaces with macrophages. The nine patients with subacute hypersensitivity pneumonitis showed small, rounded opacities and patchy air-space opacification on CT scans. These findings reflected the histologic findings, which consisted of interstitial pneumonitis, cellular bronchiolitis, and small, noncaseating granulomas. The six patients with symptoms for 12 months or longer also showed irregular linear opacities on CT scans, corresponding to areas of fibrosis. CT scans were superior to radiographs in helping to assess the type and extent of abnormalities, and high-resolution CT scans were superior to conventional CT scans.  相似文献   
22.
IntroductionDislocation following total hip replacement continues to be a problem for which no completely satisfactory solution has been found. Several methods have been proposed to reduce the incidence of hip dislocations with varying degrees of success, including elevated rim liners, constrained liners and large diameter bearings. We present our experience with the double mobility acetabular component in patients at high risk of instability.MethodsThis was a retrospective review of 65 primary total hip arthroplasties in 55 patients (15 men, 40 women), performed between October 2005 and November 2009. The majority (80%) of patients had at least two and 26% had at least three risk factors for instability. The mean age was 76 years (range: 44–92 years). The patients were followed up for a mean duration of 60 months (range: 36–85 months).ResultsFourteen patients died and one was lost to follow-up, leaving fifty hips for final assessment. Until the final follow-up appointment, no patients had dislocation and none required revision surgery. The mean Oxford hip score improved from 45.0 to 26.5 (p<0.0001). The mean Merle d’Aubigné pain score improved from 1.4 to 4.9 (p<0.0001), the walking score from 2.3 to 3.1 (p<0.07) and the absolute hip function score from 5.4 to 10.8 (p<0.0001). There were no clinical or radiographic signs of loosening.ConclusionsThe double mobility acetabular component was successful at preventing dislocation during early to medium-term follow-up. However, as data are still lacking with regard to polyethylene wear rates at the additional bearing surface, it would be prudent to restrict the use of this implant to selected patients at high risk of instability.  相似文献   
23.
24.
25.
Speech-controlled generation of radiology reports   总被引:1,自引:0,他引:1  
Voice entry has been successfully employed to generate radiology reports with a word recognizer with a 1,000-word lexicon capacity. About 50% of reports were able to be dictated with a single 900-word lexicon. This was split into five sections by anatomic or subspecialty application. Each was augmented to 900 words. By switching from one lexicon to another, it was possible to dictate more than 70% of reports. With exclusive use of three lexicons in subspecialty areas (gastrointestinal radiology, neuroradiology, and mammography), and with further modification of the respective vocabulary, it has been possible to employ the system 88% of the time. Twelve percent of cases included wording that was beyond the scope of the lexicon. Computer subsets that allow different translations of some words when used in different contexts have been used. Some of these are used as triggers that will print whole lines, sentences, or even complete reports. Dictation times with voice entry take about 20% longer. Recognition reliability has been greater than 95%.  相似文献   
26.
27.
Several sets of model-based estimates (synthetic estimates) of the prevalence of risk factors for coronary heart disease for small areas in England have been developed. These have been used in policy documents to indicate which areas are in need of intervention. In general, these models have not been subjected to validity assessment. This paper describes a validity assessment of 16 sets of synthetic estimates, by comparison of the models with national, regional and local survey-based estimates, and local mortality rate estimates. Model-based estimates of the prevalence of smoking, low fruit and vegetable consumption, obesity, hypertension and raised cholesterol are found to be valid.  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