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   550篇
  免费   56篇
  国内免费   4篇
耳鼻咽喉   2篇
儿科学   30篇
妇产科学   3篇
基础医学   69篇
口腔科学   8篇
临床医学   109篇
内科学   131篇
皮肤病学   9篇
神经病学   21篇
特种医学   88篇
外科学   47篇
综合类   6篇
预防医学   40篇
眼科学   4篇
药学   19篇
  2篇
肿瘤学   22篇
  2023年   6篇
  2021年   7篇
  2020年   8篇
  2019年   8篇
  2018年   11篇
  2017年   7篇
  2016年   8篇
  2015年   7篇
  2014年   19篇
  2013年   20篇
  2012年   23篇
  2011年   12篇
  2010年   21篇
  2009年   27篇
  2008年   15篇
  2007年   18篇
  2006年   27篇
  2005年   20篇
  2004年   21篇
  2003年   18篇
  2002年   14篇
  2001年   17篇
  2000年   6篇
  1999年   16篇
  1998年   20篇
  1997年   22篇
  1996年   17篇
  1995年   18篇
  1994年   18篇
  1993年   11篇
  1992年   13篇
  1991年   8篇
  1990年   10篇
  1989年   15篇
  1988年   5篇
  1987年   8篇
  1986年   8篇
  1985年   11篇
  1984年   4篇
  1983年   8篇
  1982年   4篇
  1980年   4篇
  1979年   6篇
  1978年   6篇
  1977年   4篇
  1976年   9篇
  1975年   6篇
  1974年   5篇
  1969年   3篇
  1958年   2篇
排序方式: 共有610条查询结果,搜索用时 31 毫秒
31.
Immunoglobulin G subclass concentrations were measured in paired foetal (cord) and maternal serum specimens at delivery from 27 IgA-deficient (serum IgA < 0.01 g/l) and 15 control women. IgA-deficient women had significantly higher serum IgGl and IgG3 concentrations than control women but 2 of the group had concomitant IgG2/IgG4 deficiency and a further 12 had low IgG4 concentrations (serum IgG4 < 0.025 g/l). Foetal serum also had significantly higher IgGl concentrations than control foetal serum but lower IgG2 and IgG4 levels. Concentrations of IgG subclasses and IgM were measured in breast milk collected on the fifth day postpartum from 19 of these IgA-deficient and 18 control women. Between-group differences in IgG subclass levels resembled those in serum. Compared with serum, proportionally less IgG3 was present in milk in both groups although the contribution of IgG3 to total IgG was not less than that of IgG4. Slightly higher IgM was found in milk from the IgA-deficient mothers.  相似文献   
32.
Magnetic resonance imaging of benign mediastinal masses   总被引:1,自引:0,他引:1  
  相似文献   
33.
34.
Multisection, dual-echo magnetic resonance (MR) transaxial images of blood vessels contain both anatomic and qualitative information about flow. Even so, the images are produced as a series of two-dimensional tomographic sections from which full visualization of connected structures is difficult. A computer algorithm was developed that automatically detects flowing blood based on pixel intensity and calculated T2 and provides reconstructed views of vessels while analyzing and displaying flow characteristics. Images of abdominal vessels, aortic aneurysms, and the heart were encoded by flow and color to demonstrate depth. In addition, these data were reconstructed to derive a more accurate assessment of patency. With this technique, transaxial images can be used to analyze flow patterns, determine patent areas, and visualize all levels of vessels in a single image.  相似文献   
35.
36.
37.
A simple way of detecting pyrazinamide resistance   总被引:3,自引:0,他引:3  
E Brander 《Tubercle》1972,53(2):128-131
  相似文献   
38.
论我国医疗美容产业的可持续发展   总被引:4,自引:1,他引:3  
目的探讨我国医疗美容事业的产业化属性、经济学地位,以及如何达到全面、协调和可持续发展的大目标。方法逻辑论证。结果认识到医疗美容产业是“医疗美容经济”系统的核心要素;揭示了医疗美容产业具有“人本经济”的特征,民营医疗美容产业是发展医疗美容事业的重要力量,医疗美容产业的发展是当代中国医学美学与美容医学整体学科建设和发展的社会基础和经济基础。结论医疗美容产业的形成是医疗美容事业在社会主义市场经济条件下发展的必然趋势,同时提出了医疗美容产业健康发展的三大措施:增强产业意识;加强行业规范;实行人本管理。最终的结论是:医疗美容事业利用产业化机制,走产业化发展的道路,促进了整个社会医疗美容事业的全面、协调和可持续发展。  相似文献   
39.
40.
BACKGROUND AND PURPOSE: To evaluate (a) whether an active weight reduction strategy based on the cognitive-behavioral approach and an initial very-low-calorie diet might lead to short- and long-term weight loss and alleviation of OSAS; and (b) whether the results of this intervention could be enhanced by combining it with nasal continuous positive airway pressure (CPAP) treatment during the first 6 months. PATIENTS AND METHODS: Thirty-one obese male symptomatic sleep apnea patients underwent a 2-year weight reduction program with total follow-up of 36 months from baseline. The mean age (+/-SD) was 49.1+/-7.9 years, body mass index 43.8+/-5.4, and oxygen desaturation index (ODI4) 51.3+/-31.1. The patients were randomized to CPAP (17 patients) and non-CPAP groups (14 patients). RESULTS: The mean weight loss was 19.1+/-10.2 kg (14% of the original weight) for the whole group at 6 months, 18.3+/-13.2 (13%) at 12 months and 12.6+/-14.7 kg (9%) at 24 months. Excellent or good treatment results, as defined in terms of an ODI4 (average number of oxygen desaturation events p/h>4% from baseline) reduction of at least 50% from the baseline, were seen in 61% of patients at 6 months and were still observable in 42% of patients at 24 months. The correlations between changes in weight and in ODI4 were 0.59 (P<0.01) at 6 months, 0.68 (P<0.01) and 0.75 (P<0.01) at 24 months. Adding CPAP treatment to the weight reduction therapy for the first 6 months did not result in greater weight loss or diminution of desaturation indices (without CPAP) at any time point. One year after the termination of the program the mean weight loss was 6.6+/-12.9 kg, and 42% of patients still showed at least 5% weight loss as compared with their original weight. CONCLUSION: Satisfactory weight loss associated with improvement of OSAS could be achieved by means of a cognitive-behavioral weight loss program. Adding CPAP in the initial phase of the weight reduction program did not result in significantly greater weight loss.  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