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   423篇
  免费   46篇
  国内免费   8篇
儿科学   13篇
妇产科学   11篇
基础医学   34篇
口腔科学   37篇
临床医学   43篇
内科学   143篇
皮肤病学   10篇
神经病学   26篇
特种医学   72篇
外科学   23篇
综合类   8篇
预防医学   21篇
眼科学   4篇
药学   26篇
肿瘤学   6篇
  2024年   1篇
  2023年   2篇
  2022年   2篇
  2020年   2篇
  2019年   5篇
  2018年   4篇
  2017年   2篇
  2016年   4篇
  2015年   10篇
  2014年   6篇
  2013年   18篇
  2012年   5篇
  2011年   8篇
  2010年   19篇
  2009年   15篇
  2008年   12篇
  2007年   13篇
  2006年   3篇
  2005年   4篇
  2004年   3篇
  2003年   5篇
  2002年   5篇
  2001年   5篇
  2000年   2篇
  1999年   5篇
  1998年   21篇
  1997年   36篇
  1996年   33篇
  1995年   20篇
  1994年   24篇
  1993年   20篇
  1992年   4篇
  1991年   11篇
  1990年   8篇
  1989年   15篇
  1988年   15篇
  1987年   12篇
  1986年   14篇
  1985年   11篇
  1984年   7篇
  1983年   16篇
  1982年   18篇
  1981年   15篇
  1980年   6篇
  1979年   2篇
  1978年   2篇
  1977年   1篇
  1976年   3篇
  1975年   2篇
  1970年   1篇
排序方式: 共有477条查询结果,搜索用时 687 毫秒
71.
72.
White blood cell count, acid-base balance, PO2, and complement function in five uremic patients undergoing a single hemoperfusion employing activated charcoal coated with methacrylate were studied. After 20 min on hemoperfusion, a marked leukopenia [ranging from 6,080 +/- 526 to 3,740 +/- 1,124 (p less than 0.02)] and hypoxemia [ranging from 106 +/- 13.8 to 80.2 +/- 11.9 mm Hg (p less than 0.02)] were observed. At the same time, total hemolytic complement decreased from 135 +/- 15.7 to 123 +/- 14.7 U/ml (p less than 0.001) and alternative pathway activity from 38.1 +/- 5.1 to 33.1 +/- 6.7 U/ml (p less than 0.005). C3 and B cleavage fragments were detected in the samples tested, thus demonstrating the activation of the complement alternative pathway. After 60 min, the different parameters tended to increase but did not reach the baseline levels. A direct correlation between the degree of leukopenia and the reduction of PO2 throughout the hemoperfusion period was found. pH PCO2, and HCO-3 did not change throughout the hemoperfusion period. The results demonstrate that complement activation, leukopenia, and hypoxemia occur during hemoperfusion.  相似文献   
73.
Becker  CD; Quenville  NF; Burhenne  HJ 《Radiology》1988,167(1):63-68
Recurrent cholelithiasis must be expected after gallstone removal without cholecystectomy. Chemical gallbladder ablation may offer prevention but requires preliminary cystic duct occlusion. Radio-frequency (RF) electrocoagulation of the cystic duct was performed in 15 pigs to induce occlusion by a controlled thermal epithelial injury. A flexible coagulation catheter was placed into the cystic duct lumen under fluoroscopic control by means of either subhepatic cholecystostomy or direct, percutaneous transhepatic gallbladder puncture. Complete cystic duct occlusion was proved in 14 animals. Follow-up ranged from 1 to 17 weeks (mean, 11 weeks). Histologically, the RF technique induced an intense chronic inflammatory and fibroblastic reaction, which eventually obliterated the coagulated cystic duct segments. There was no epithelial regeneration or recanalization of the fibrotic cystic duct segments. The adjacent structures, particularly the cystic artery, were intact in all specimens.  相似文献   
74.
75.
76.
77.
78.
79.
Oral Diseases (2010) 17 , 33–44 Objectives: To study the natural aetiopathology of jaw atrophy after tooth loss, unaltered by prosthetic procedures, an historical population without modern dental treatment was examined. Methods: Based on the hypothesis that there are predictable changes in shape during jaw‐atrophy, frequency and degree of atrophy as well as clinical aspects of bone quality and resorption were determined in the skeletal remains of 263 individuals. The potential association between age and frequency/severity of atrophy was analysed. Results: Atrophy in at least one jaw segment was present in 45.2% of the analysed jaw specimens. The residual ridge underwent a series of changes in shape and height following the pattern of resorption described for modern populations. The severity of these alterations was associated with the age of the individual and the region within the jaw. Atrophy was frequently related to structural degradation of the covering cortical layer. Conclusions: These findings prove that atrophy of the jaw evidently does occur, displaying similar patterns of resorption in a population without modern prosthetics, where the negative effect of ill‐fitting dentures is excluded. The basic information about alterations of shape and the cortical layer covering the residual crest might help to provide a deeper insight into aetiopathological mechanisms of this common oral disease.  相似文献   
80.
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