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   209篇
  免费   11篇
耳鼻咽喉   3篇
儿科学   14篇
妇产科学   1篇
基础医学   27篇
口腔科学   8篇
临床医学   18篇
内科学   41篇
皮肤病学   1篇
神经病学   4篇
特种医学   47篇
外科学   10篇
预防医学   29篇
眼科学   1篇
药学   7篇
中国医学   1篇
肿瘤学   8篇
  2021年   2篇
  2020年   1篇
  2018年   2篇
  2016年   6篇
  2015年   1篇
  2014年   3篇
  2013年   4篇
  2012年   3篇
  2011年   3篇
  2010年   11篇
  2009年   10篇
  2008年   4篇
  2007年   6篇
  2006年   7篇
  2005年   8篇
  2004年   7篇
  2003年   6篇
  2002年   3篇
  2001年   5篇
  2000年   2篇
  1999年   2篇
  1998年   12篇
  1997年   15篇
  1996年   7篇
  1995年   4篇
  1994年   8篇
  1993年   3篇
  1992年   1篇
  1991年   3篇
  1989年   8篇
  1988年   7篇
  1987年   10篇
  1986年   6篇
  1985年   11篇
  1984年   2篇
  1983年   4篇
  1982年   2篇
  1981年   1篇
  1980年   4篇
  1979年   1篇
  1978年   1篇
  1977年   2篇
  1976年   4篇
  1975年   6篇
  1973年   1篇
  1966年   1篇
排序方式: 共有220条查询结果,搜索用时 15 毫秒
211.
Human endothelial cells synthesize protein S   总被引:6,自引:0,他引:6  
Fair  DS; Marlar  RA; Levin  EG 《Blood》1986,67(4):1168-1171
Human umbilical vein endothelial cells were analyzed for the presence of prothrombin, factor VII, protein C, and protein S in culture supernatants and cell extracts using specific radioimmunoassays. Only protein S was detected. Conditioned medium from 24-hour cultures and cell lysates contained 21.7 ng/mL and 88.8 ng/10(7) cells of protein S, respectively. Intrinsic labeling and immunoprecipitation indicated that protein S was synthesized and secreted as a 75,000 molecular weight protein. Vitamin K, phorbol myristate acetate, and thrombin increased the production or specific activity (determined from activity/antigen ratios of 0.99 to 1.07, 0.93 to 1.04, and 0.90 to 1.04, respectively) of protein S. While untreated cells secreted a partially active protein S (activity/antigen = 0.40), warfarin greatly decreased the specific activity (less than 0.10) of this molecule, suggesting that endothelial cells contain the enzymes required for the carboxylation of selected glutamic acid residues. The production of protein S by these cells supports the hypothesis that cofactor production and expression by the endothelial cells may play a significant regulatory role in the initiation, propagation, and suppression of hemostasis and thrombosis.  相似文献   
212.
A 42 year-old male former semi-professional soccer player sustained a right lower extremity popliteal contusion during a soccer game. He was clinically diagnosed with a possible traumatic deep vein thrombosis (DVT), and sent for confirmatory tests. A duplex doppler ultrasound was positive for DVT, and the patient was admitted to hospital for anticoagulation (unfractionated heparin, warfarin). Upon discharge from hospital the patient continued oral warfarin anticoagulation (six months), and the use of compression stockings (nine months). He followed up with his family doctor at regular intervals for serial coagulation measurements, and ultrasound examinations. The patient's only identified major thrombotic risk factor was the traumatic injury. One year after the initial deep vein thrombosis (DVT) the patient returned to contact sport, however he continued to have intermittent symptoms of right lower leg pain and right knee effusion.  相似文献   
213.

Background  

Although a grossly disproportionate burden of disease from HIV/AIDS, TB and malaria remains in the Global South, these infectious diseases have finally risen to the top of the international agenda in recent years. Ideal strategies for combating these diseases must balance the advantages and disadvantages of 'vertical' disease control programs and 'horizontal' capacity-building approaches.  相似文献   
214.
Mutations of factor VIII cleavage sites in hemophilia A   总被引:10,自引:1,他引:9  
Gitschier  J; Kogan  S; Levinson  B; Tuddenham  EG 《Blood》1988,72(3):1022-1028
Hemophilia A is caused by a defect in coagulation factor VIII, a protein that undergoes extensive proteolysis during its activation and inactivation. To determine whether some cases of hemophilia are caused by mutations in important cleavage sites, we screened patient DNA samples for mutations in these sites by a two-step process. Regions of interest were amplified from genomic DNA by repeated rounds of primer- directed DNA synthesis. The amplified DNAs were then screened for mutations by discriminant hybridization using oligonucleotide probes. Two cleavage site mutations were found in a survey of 215 patients. A nonsense mutation in the activated protein C cleavage site at amino acid 336 was discovered in a patient with severe hemophilia. In another severely affected patient, a mis-sense mutation results in a substitution of cysteine for arginine in the thrombin activation site at amino acid 1689. This defect is associated with no detectable factor VIII activity, but with normal levels of factor VIII antigen. The severe hemophilia in this patient was sporadic; analysis of the mother suggested that the mutation originated in her gametes or during her embryogenesis. The results demonstrate that this approach can be used to identify factor VIII gene mutations in regions of the molecule known to be important for function.  相似文献   
215.
216.
Magnetic resonance (MR) imaging of the patient with acute cervical injury is important because of the potential prognostic significance of the appearance of the spinal cord at the time of injury. However, cervical traction may involve equipment incompatible with the magnetic environment, and transferring the patient to the imaging table may make it difficult to maintain traction. The authors describe a simple, inexpensive, and reliable method for providing cervical traction within the magnet room.  相似文献   
217.

Background  

There is little experience with carefully developed interventions in the HIV/STI prevention field aimed at adult heterosexual target groups in the Netherlands. The ability to apply intervention development protocols, like Intervention Mapping, in daily practice outside of academia, is a matter of concern. An urgent need also exists for interventions aimed at the prevention of STI in migrant populations in the Netherlands. This article describes the theory and evidence based development of HIV/STI prevention interventions by the Municipal Public Health Service Rotterdam Area (MPHS), the Netherlands, for heterosexual migrant men with Surinamese, Dutch-Caribbean, Cape Verdean, Turkish and Moroccan backgrounds.  相似文献   
218.
219.
220.
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