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   786篇
  免费   46篇
  国内免费   1篇
耳鼻咽喉   19篇
儿科学   16篇
妇产科学   25篇
基础医学   80篇
口腔科学   24篇
临床医学   43篇
内科学   120篇
皮肤病学   11篇
神经病学   79篇
特种医学   63篇
外科学   113篇
综合类   7篇
预防医学   89篇
眼科学   36篇
药学   50篇
中国医学   18篇
肿瘤学   40篇
  2023年   10篇
  2022年   20篇
  2021年   21篇
  2020年   25篇
  2019年   33篇
  2018年   27篇
  2017年   24篇
  2016年   16篇
  2015年   24篇
  2014年   33篇
  2013年   30篇
  2012年   62篇
  2011年   51篇
  2010年   37篇
  2009年   24篇
  2008年   35篇
  2007年   40篇
  2006年   22篇
  2005年   22篇
  2004年   13篇
  2003年   24篇
  2002年   18篇
  2001年   15篇
  2000年   21篇
  1999年   13篇
  1998年   6篇
  1997年   6篇
  1996年   5篇
  1994年   5篇
  1992年   5篇
  1991年   4篇
  1990年   6篇
  1989年   7篇
  1988年   6篇
  1986年   6篇
  1985年   9篇
  1984年   8篇
  1983年   6篇
  1980年   4篇
  1979年   4篇
  1978年   6篇
  1976年   7篇
  1975年   5篇
  1974年   7篇
  1972年   3篇
  1971年   6篇
  1970年   8篇
  1969年   6篇
  1968年   9篇
  1967年   4篇
排序方式: 共有833条查询结果,搜索用时 15 毫秒
11.
12.
13.
In certain instances, Th17 responses are associated with severe immunopathology. T cell–intrinsic mechanisms that restrict pathogenic effector functions have been described for type 1 and 2 responses but are less well studied for Th17 cells. Here, we report a cell-intrinsic feedback mechanism that controls the pathogenicity of Th17 cells. Th17 cells produce IL-24, which prompts them to secrete IL-10. The IL-10–inducing function of IL-24 is independent of the cell surface receptor of IL-24 on Th17 cells. Rather, IL-24 is recruited to the inner mitochondrial membrane, where it interacts with the NADH dehydrogenase (ubiquinone) 1 α subcomplex subunit 13 (also known as Grim19), a constituent of complex I of the respiratory chain. Together, Grim19 and IL-24 promote the accumulation of STAT3 in the mitochondrial compartment. We propose that IL-24–guided mitochondrial STAT3 constitutes a rheostat to blunt extensive STAT3 deflections in the nucleus, which might then contribute to a robust IL-10 response in Th17 cells and a restriction of immunopathology in experimental autoimmune encephalomyelitis.  相似文献   
14.
15.
We investigated glutathione S-transferase (GST) P1I le (105) Val, T1, and M1 polymorphisms in 45 patients with documented cryptogenic cirrhosis and 56 healthy control subjects. Polymerase chain reaction-based procedures were performed in the studied populations to confirm the genotypes of GSTT1, M1, and P1. Ile/Val and Val/Val GSTP1 genotypes were more frequent in the patients with cirrhosis (n = 39, 87%) than in the control subjects (n = 10; 18%) (odds ratio [OR] 34.04; 95% confidence interval [CI] 10.70 to 108.31, P < 0.001). Among these patients with cirrhosis, 16 were heterozygous and 23 were homozygous, whereas only one person in the control group was homozygous. The GSTM1 null genotype was also more prevalent in cirrhotic patients than in healthy control subjects (OR 6.83, 95% CI 2.53 to 18.42, P < 0.001). The rate of GSTT1 deletion did not show a significant difference between the two groups (OR 2.35, 95% CI 0.76 to 7.28, P = 0.111). To our knowledge, this is the first evidence that GSTP1 and GSTM1 polymorphisms may be related to the development of cirrhosis by unknown mechanisms. The significant association of cryptogenic cirrhosis with Val/Val GSTP1 genotype encoding a low detoxification activity protein implicates this polymorphism as a risk factor for the occurrence of the disease. Presented as an abstract at the Forty-Fourth Annual Meeting of The Society for Surgery of the Alimentary Tract, Orlando, Florida, May 19–22, 2003 (Poster of Distinction).  相似文献   
16.
Sport Sciences for Health - The purpose of this study is to investigate the Bottom–Up Rise Strength Transfer (BURST) induced by massed vs. distributed-rehabilitative exercise training....  相似文献   
17.
The authors operated on 7 children (5 girls, 2 boys) suffering from osteogenesis imperfecta (oi) type I according to Sillence classification, with lower limbs discrepancy. We elongated 10 segments (7 femurs and 3 tibias). Mean age at operation time was 14.7 years (13-17 years). The mean leg length discrepancy was 9.3 cm (4-18 cm), and shortening of one bone was 6.5 cm (4-9 cm). We used Ilizarov technique twice in tibial lengthening. We used Wagner technique in one tibial elongation and in 7 femur elongation. Except for one tibia, in the remaining cases there was Rush rod inserted intramedullary in the bone being elongated. During tibial elongation we fixed lateral malleous by screw. The osteotomy was performed in proximal metaphysis of the 5 femurs and 3 tibias, and in distal femurs in two cases. The elongation was 1 mm for day, with frequency 4 x 1/4 mm. The mean bone lengthening achieved was 5.5 cm (2-9 cm); the mean lengthening of the limb was 7.9 cm (2-18 cm). The mean time of elongation was 2.8 months (2-5 months). Elongation index was 26 days for 1 cm of lengthening. The mean time of fixator removal was 9.2 months (4-13 months). Healing index was 58 day/1 cm (overall number of days for 1 cm lengthening). The complications occurred in all the patients. Although the risk of numerous complication is high, lower limbs lengthening in children with type I osteogeneis imperfecta is possible to perform and allows equalizing discrepant limbs or, at least reducing the difference.  相似文献   
18.
Rad AN  Flores JI  Rosson GD 《Microsurgery》2008,28(6):407-411
Autologous breast reconstruction with microsurgical free tissue transfer has become routine, and perforator-based adipocutaneous flaps are recognized as an excellent option for many patients. Current efforts to optimize patient outcomes focus on minimizing operative morbidity both at the donor and recipient sites. The DIEAP flap avoids most of the abdominal wall morbidity associated with the TRAM. At the recipient site, however, partial rib resection, for access to the internal mammary (IM) artery and vein as recipient vessels, has a risk of chest wall pain, deformity, and pneumothorax. Perhaps more importantly, sacrifice of the IM vessels precludes their use for potential future coronary revascularization. To avoid this, the intercostal perforating branches from the internal mammary system may be used as recipient vessels for microanastomosis. This has been well described using suture technique, although the use of a mechanical coupling device for arterial anastomosis to the perforator has not been reported. We report nine cases whereby a mechanical coupling device was used to perform both the arterial and venous anastomoses of DIEAP and SIEA flap pedicles to IM intercostal perforating vessels. Flap ischemia time was shorter in all cases, allowed ease of anastomosis for vessel size mismatch, and is technically easier in deep wounds. This technique is a further refinement to free flap breast reconstruction and is a powerful application of the coupling device.  相似文献   
19.
20.
ObjectivesHunt and Hess (HH) and World Federation of Neurological Surgeons (WFNS) grades are commonly used to report clinical severity of aneurysmal subarachnoid hemorrhage (aSAH). We sought to determine the impact of early neurological changes and the timing of clinical grade assignment on the prognostication accuracy.MethodsWe retrospectively reviewed a cohort of consecutive patients with aSAH who were admitted to an academic center. Patients with confirmed aneurysmal cause were included. Relevant clinical data including daily clinical grades, imaging data and functional outcome were analyzed. Favorable outcome was defined as mRS 0 to 3. Early neurological improvement (ENI) and early neurological deterioration (END) were respectively defined as any improvement or deterioration of HH grades from hospital day 1 to the earliest time from hospital day 2 to 5.ResultsOf 310 patients, 24% experienced early neurological changes from hospital day 1 to 3. For each point increase in HH grades from day 1 to day 3, the odds ratio for worse outcome was 2.57 (95% CI [1.74-3.79]) and for each point decrease in HH grades from day 1 to day 3, the odds ratio for worse outcome was 0.28 (95% CI [0.17-0.47]). Receiver Operating Characteristic curve analysis revealed that clinical grades on day 3 had higher accuracy in predicting worse outcome than clinical grades on day 1.ConclusionEarly changes in neurological status can alter trajectory of hospital course and functional outcome. The prognostic accuracy of the clinical grades from hospital day 3 is significantly greater than those on admission.  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