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   291篇
  免费   19篇
  国内免费   2篇
耳鼻咽喉   1篇
儿科学   6篇
妇产科学   2篇
基础医学   41篇
口腔科学   16篇
临床医学   32篇
内科学   61篇
皮肤病学   10篇
神经病学   51篇
特种医学   6篇
外科学   25篇
综合类   1篇
预防医学   21篇
眼科学   8篇
药学   18篇
肿瘤学   13篇
  2024年   1篇
  2023年   7篇
  2022年   5篇
  2021年   18篇
  2020年   5篇
  2019年   6篇
  2018年   16篇
  2017年   4篇
  2016年   10篇
  2015年   10篇
  2014年   15篇
  2013年   21篇
  2012年   29篇
  2011年   24篇
  2010年   17篇
  2009年   15篇
  2008年   22篇
  2007年   17篇
  2006年   8篇
  2005年   4篇
  2004年   9篇
  2003年   9篇
  2002年   4篇
  2001年   1篇
  1998年   1篇
  1997年   2篇
  1996年   2篇
  1993年   1篇
  1992年   2篇
  1991年   2篇
  1990年   2篇
  1989年   5篇
  1988年   1篇
  1987年   2篇
  1986年   3篇
  1981年   1篇
  1977年   2篇
  1976年   2篇
  1974年   1篇
  1973年   1篇
  1972年   1篇
  1969年   2篇
  1966年   1篇
  1965年   1篇
排序方式: 共有312条查询结果,搜索用时 231 毫秒
1.
Graefe's Archive for Clinical and Experimental Ophthalmology - Retinal microvascular endothelial dysfunction is thought to be of importance in the development of ocular vascular diseases....  相似文献   
2.
TLR4 gene variants modify endotoxin effects on asthma   总被引:6,自引:0,他引:6  
BACKGROUND: Environmental exposure to endotoxin might have a crucial role in immune maturation and development of asthma. OBJECTIVE: The aim of this study was to investigate whether the effect of endotoxin concentration in settled house dust on asthma is modified by the presence of variation in the TLR4 gene. METHODS: We performed a cross-sectional study within the German follow-up of the European Community Respiratory Health Survey. Multivariate logistic regression analysis and nonparametric effect estimates (S-Plus) were applied to examine the association between endotoxin exposure and diagnosed asthma, related clinical symptoms, and bronchial hyperreactivity (BHR) stratified for noncarriers and carriers of G299/I399 polymorphism in the TLR4 gene. RESULTS: In the noncarrier group (n = 279), the prevalence of asthma was significantly increased with elevated endotoxin levels in house dust with adjusted odds ratio 6.24 (95% CI, 1.33-29.17) in the second tertile, and 4.54 (95% CI, 0.94-21.96) in the third tertile compared with the lowest endotoxin tertile. The carriers of the polymorphisms (n = 55) showed a nonsignificant trend to have a lower risk of asthma (crude odds ratio, 0.67; 95% CI, 0.06-8.06 for the second tertile and 1.33; 95% CI, 0.17-10.58 for the third tertile). We found a similar association for wheeze and endotoxin exposure that was also attenuated in subjects with G299/I399 polymorphisms. CONCLUSIONS: The G299/I399 polymorphisms were associated with a modified response to endotoxin, but the functional relationship still needs clarification.  相似文献   
3.
4.
5.
6.
In vitro expanded adipose-derived stromal cells (ASCs) are a useful resource for tissue regeneration. Translation of small-scale autologous cell production into a large-scale, allogeneic production process for clinical applications necessitates well-chosen raw materials and cell culture platform. We compare the use of clinical-grade human platelet lysate (hPL) and fetal bovine serum (FBS) as growth supplements for ASC expansion in the automated, closed hollow fibre quantum cell expansion system (bioreactor). Stromal vascular fractions were isolated from human subcutaneous abdominal fat. In average, 95?×?106 cells were suspended in 10% FBS or 5% hPL medium, and loaded into a bioreactor coated with cryoprecipitate. ASCs (P0) were harvested, and 30?×?106 ASCs were reloaded for continued expansion (P1). Feeding rate and time of harvest was guided by metabolic monitoring. Viability, sterility, purity, differentiation capacity, and genomic stability of ASCs P1 were determined. Cultivation of SVF in hPL medium for in average nine days, yielded 546?×?106 ASCs compared to 111?×?106 ASCs, after 17?days in FBS medium. ASCs P1 yields were in average 605?×?106 ASCs (PD [population doublings]: 4.65) after six days in hPL medium, compared to 119?×?106 ASCs (PD: 2.45) in FBS medium, after 21?days. ASCs fulfilled ISCT criteria and demonstrated genomic stability and sterility. The use of hPL as a growth supplement for ASCs expansion in the quantum cell expansion system provides an efficient expansion process compared to the use of FBS, while maintaining cell quality appropriate for clinical use. The described process is an obvious choice for manufacturing of large-scale allogeneic ASC products.  相似文献   
7.
8.
Abstract. Hepatitis B immune globulin has been prepared for clinical trials in Sweden. The relative amount of antibodies to the hepatitis B antigen recovered in the respective fractionation steps was evaluated by hemagglutination, immunoelectro-osmophoresis and radial immunodiffusion. About one third of the antibody amount present in the original plasma pool was recovered in fraction II. Hepatitis B antigen was neither demonstrated in the various fractionation steps nor in the final immune globulin preparation.  相似文献   
9.
Static and dynamic hyperinflation is an important factor of exertional dyspnea in patients with severe COPD. This proof-of-concept intervention trial sought to study whether laughter can reduce hyperinflation through repetitive expiratory efforts in patients with severe COPD. For small groups of patients with severe COPD (n = 19) and healthy controls (n = 10) Pello the clown performed a humor intervention triggering regular laughter. Plethysmography was done before and up to 24 hours after intervention. Laughing and smiling were quantified with video-analysis. Real-time breathing pattern was assessed with the LifeShirt™, and the psychological impact of the intervention was monitored with self-administered questionnaires. The intervention led to a reduction of TLC in COPD (p = 0.04), but not in controls (p = 0.9). TLC reduction was due to a decline of the residual volume. Four (22 [CI 95% 7 to 46] %) patients were ≥10% responders. The frequency of smiling and TLC at baseline were independent predictors of TLC response. The humor intervention improved cheerfulness, but not seriousness nor bad mood. In conclusion, smiling induced by a humor intervention was able to reduce hyperinflation in patients with severe COPD. A smiling-derived breathing technique might complement pursed-lips breathing in patients with symptomatic obstruction.  相似文献   
10.
The shape of a target object could influence maximum grip aperture in human grasping movements in several different ways. Maximum grip aperture could be influenced by the required precision of digit placement, by the aim to avoid colliding with the wrong parts of the target objects, by the mass of the target objects, or by (mis)judging the width or the volume of the target objects. To examine the influence of these five factors, we asked subjects to grasp five differently shaped target objects with the same maximal width, height and depth and compared their maximum grip aperture with what one would expect for each of the five factors. The five target objects, a cube, a three-dimensional plus sign, a rectangular block, a cylinder and a sphere, were all grasped with the same final grip aperture. The experimentally observed maximum grip apertures correlated poorly with the maximum grip apertures that were expected on the basis of the required precision, the actual mass, the perceived width and the perceived volume. They correlated much better with the maximum grip apertures that were expected on the basis of avoiding unintended collisions with the target object. We propose that the influence of target object shape on maximum grip aperture might primarily be the result of the need to avoid colliding with the wrong parts of the target object.  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