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   818篇
  免费   78篇
  国内免费   15篇
耳鼻咽喉   5篇
儿科学   47篇
妇产科学   11篇
基础医学   104篇
口腔科学   31篇
临床医学   107篇
内科学   213篇
皮肤病学   34篇
神经病学   20篇
特种医学   143篇
外科学   51篇
综合类   37篇
预防医学   23篇
眼科学   5篇
药学   60篇
中国医学   2篇
肿瘤学   18篇
  2023年   4篇
  2022年   2篇
  2021年   14篇
  2020年   12篇
  2019年   17篇
  2018年   12篇
  2017年   17篇
  2016年   17篇
  2015年   25篇
  2014年   29篇
  2013年   37篇
  2012年   25篇
  2011年   18篇
  2010年   50篇
  2009年   40篇
  2008年   20篇
  2007年   32篇
  2006年   23篇
  2005年   22篇
  2004年   12篇
  2003年   19篇
  2002年   16篇
  2001年   8篇
  2000年   13篇
  1999年   15篇
  1998年   45篇
  1997年   40篇
  1996年   36篇
  1995年   27篇
  1994年   35篇
  1993年   29篇
  1992年   7篇
  1991年   10篇
  1990年   8篇
  1989年   21篇
  1988年   17篇
  1987年   18篇
  1986年   13篇
  1985年   9篇
  1984年   5篇
  1983年   11篇
  1982年   14篇
  1981年   9篇
  1980年   14篇
  1978年   5篇
  1977年   13篇
  1976年   7篇
  1975年   5篇
  1956年   3篇
  1955年   2篇
排序方式: 共有911条查询结果,搜索用时 15 毫秒
51.
52.
The extent of length polymorphisms of the heterochromatic and euchromatic segment of the human Y chromosome were investigated in 15 boys with acute leukemia and were compared with 15 normal controls. A greater value of the Yh/F index in relation to controls was established (P < 0.05). The length of the euchromatic segment was also shorter in the patients than the controls (P < 0.05).  相似文献   
53.
ABSTRACT. Serial plasma glucose estimations were performed in 44 light-for-date infants and 17 infants of diabetic mothers fed 2, 3 or 4-hourly with feeds containing 10 % additional carbohydrate in the form of a glucose polymer (Caloreen). In the infants fed 2 and 3-hourly, plasma glucose was higher following the high carbohydrate feeds, particularly immediately before the next feed was due. Given 4-hourly, the high carbohydrate feed had little effect in most light-for-date infants, and in one light-for-date infant and two infants of diabetic mothers the plasma glucose was lower at the end of 4 hours than following normal formula. It is concluded that the addition of glucose polymer to feeds given 2 and 3 hourly has a potentially useful effect in neonates at risk of developing hypoglycaemia, but it cannot be used to increase the feed interval to 4 hours.  相似文献   
54.
A series of 73 hypopharyngeal (Zenker's) diverticula is reported and the choice of treatment and technique of excision are discussed. The problems of excision include operation on an infected site with limited access but few patients are unfit for the procedure. Preoperatively the sac should be packed and the oesophagus stented. The side of approach is unimportant as the condition is essentially midline. Cricopharyngeal myotomy appears to reduce the recurrence rate, possibly by improving coordination of pharyngeal contraction and upper oesophageal relaxation. The use of electrocoagulation is not recommended as 20% of patients require repeated general anaesthesia and the procedure fails in 13%. For all but the smallest pouches, excision is the treatment of choice.  相似文献   
55.
56.
57.
58.
The authors describe a simple technique for diagnosis of tricuspid regurgitation. Red blood cells were labeled in vivo with 99mTc and 22 patients were studied with ECG-gated blood-pool imaging of the liver. A single region of interest was manually drawn around the liver and a time-activity curve obtained. The per cent change in liver counts during the cardiac cycle was found to be significantly higher in the 12 patients with tricuspid regurgitation (Group I) (mean, 4.04 +/- 1.6%; range, 1.3-21.4%) compared with the 10 controls (Group II) (mean, 0.35 +/- 0.16%; range, 0.013-1.3%) (p less than 0.05). Using a 1% change in liver counts as the criterion of a positive study, all 12 cases in Group I were diagnosed correctly, but there was one false positive in Group II; thus the sensitivity was 100% and the specificity 90%.  相似文献   
59.
Differential CT diagnosis of extruded nucleus pulposus   总被引:1,自引:0,他引:1  
  相似文献   
60.
This study evaluated the accuracy of the interpretation of the chest film in delineating localised abnormalities of ventilation and perfusion, as well as the overall severity of airways obstruction, exercise tolerance, and clinical condition in children with cystic fibrosis. Radiographic findings in various regions of the chest film were compared with the functional values obtained with regional lung function tests which evaluated the arrival and disappearance of boluses of radioactive nitrogen given by inhalation and infusion. While the more severely affected areas on the chest radiograph were found to correlate with similar regions on the lung function tests, as did overall scores, errors occurred in some cases if the x-ray film alone was used as a judge of regional physiological derangement. In addition the degree of airways obstruction, the exercise tolerance on a cycle ergometer, and clinical grading, each correlated significantly with the radiographic score. We conclude that the chest radiograph is a good indicator of the overall severity of the lung disease and that it correlates well with exercise tolerance and clinical condition in cystic fibrosis.  相似文献   
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