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   455篇
  免费   25篇
  国内免费   1篇
耳鼻咽喉   3篇
儿科学   34篇
妇产科学   6篇
基础医学   37篇
口腔科学   4篇
临床医学   25篇
内科学   156篇
皮肤病学   2篇
神经病学   11篇
特种医学   11篇
外科学   70篇
综合类   24篇
预防医学   58篇
眼科学   7篇
药学   21篇
中国医学   1篇
肿瘤学   11篇
  2022年   3篇
  2021年   9篇
  2020年   3篇
  2019年   10篇
  2018年   8篇
  2017年   11篇
  2016年   6篇
  2015年   9篇
  2014年   9篇
  2013年   17篇
  2012年   25篇
  2011年   21篇
  2010年   12篇
  2009年   14篇
  2008年   17篇
  2007年   18篇
  2006年   26篇
  2005年   20篇
  2004年   16篇
  2003年   13篇
  2002年   14篇
  2001年   15篇
  2000年   16篇
  1999年   7篇
  1998年   5篇
  1997年   3篇
  1995年   3篇
  1994年   3篇
  1992年   11篇
  1991年   13篇
  1990年   11篇
  1989年   16篇
  1988年   4篇
  1987年   8篇
  1986年   6篇
  1985年   7篇
  1984年   7篇
  1982年   4篇
  1980年   2篇
  1979年   2篇
  1977年   5篇
  1976年   7篇
  1973年   2篇
  1972年   2篇
  1971年   4篇
  1970年   5篇
  1968年   7篇
  1967年   2篇
  1966年   3篇
  1963年   4篇
排序方式: 共有481条查询结果,搜索用时 15 毫秒
81.
The effects of tibric acid, clofibrate, and placebo were compared in type IV hyperlipidemic patients for a 6-month period. The patients were divided into two pathological level groups according to their baseline triglyceride levels. Compared to the placebo, both tibric acid and clofibrate reduced the mean serum triglyceride concentration in the high pathological level group; however, clofibrate was also effective in the low pathological level group. The effects on total cholesterol were less pronounced with the two drugs. No effect was observed on esterified cholesterol, phospholipids, free fatty acids, and fasting blood sugar. After a 6-week follow-up period under placebo, no rebound of the triglyceride and cholesterol levels could be observed after discontinuation of the two active drugs. The other biochemical changes observed after each active treatment are discussed in relation to the different degree of activity of each active drug and to the different baseline levels of triglycerides.  相似文献   
82.
BACKGROUND: Aspirin resistance is considered to be an enigma and the data available on aspirin resistance is scarce. This study was initiated to prospectively evaluate the prevalence of aspirin resistance in patients with stable coronary artery disease by using an established method of optical platelet aggregation. METHODS AND RESULTS: We studied 50 patients who were on 150 mg of aspirin for the previous 7 days. Fasting blood samples were assessed using optical platelet aggregation (Chronolog Corp, USA). The mean platelet aggregation with 10 microm of adenosine diphosphate in our patient group was 49.42 +/- 23.29% and with 0.5 mg/ ml of arachidonic acid it was 13.58 +/- 21.40%. Aspirin resistance was defined as a mean aggregation of > or =70% with 10 microm of adenosine diphosphate and a mean aggregation of > or =20% with 0.5 mg/ml of arachidonic acid. Aspirin semi responders were defined as those meeting only one of the criteria. Based on these criteria, 2.08% patients were found to be aspirin-resistant, 39.58% were aspirin semi responders and 58.33% were aspirin responders. Females tended to be more aspirin semi responsive (p = 0.08). All other parameters tested, namely, age, smoking, diabetes mellitus, hypertension, obesity, lipids, hemoglobin, platelet count, ejection fraction and drug intake did not show any statistically significant difference among the groups. Thus, in our group 41.66% patients showed inadequate response to aspirin. Conclusions: This study shows that aspirin resistance and aspirin semi responsiveness do occur in the Indian patients and there are no reliable clinical predictors for this condition. The diagnosis therefore relies primarily on laboratory tests.  相似文献   
83.
Two new classes of tricyclic-based corticotropin-releasing factor (CRF(1)) receptor-1 antagonists were designed by constraining known 1H-pyrrolo[2,3-b]pyridine and 1H-pyrazolo[3,4-b]pyridine ligands. Pyrrole- and pyrazole-based molecules 19g and 22a, respectively, were discovered that potently bind the recombinant CRF(1) receptor (K(i) = 3.5, 2.9 nM) and inhibit adrenocorticotropic hormone (ACTH) release from rat pituitary cell culture (IC(50) = 14, 6.8 nM). These compounds show good oral bioavailabity (F = 24%, 7.0%) and serum half-lives in rats (t(1/2) = 6.3, 12 h) and penetrate the rat brain ([brain]/[plasma] = 0.27, 0.52) but tend toward large volumes of distribution (V(D) = 38, 44 L kg(-1)) and rapid clearances (CL = 70, 43 mL min(-1) kg(-1)). When given orally, both the pyrazole and the pyrrole leads dose-dependently inhibit stress-induced ACTH release in vivo. ACTH reductions of 84-86% were observed for 30 mg kg(-1) doses.  相似文献   
84.
We report an alternative approach to revascularization of the leg in a patient with acute type A aortic dissection, where other options were not feasible. An aorto-femoral extra-anatomic conduit was used to salvage the leg after major aortic surgery where further surgery or endovascular grafting would have lead to increased morbidity.  相似文献   
85.
86.
87.
Chikungunya is an arboviral infection that re-emerged in several Asian countries during 2005–2006 after a long period of quiescence. Several microbial, climatic, social and economic factors influenced the occurrence of this disease as well as the rapidity with which it swept across many countries resulting in significant morbidity. Prevention and control of such diseases require not only a strong public health infrastructure but also a precise understanding of the factors that provide a conducive environment for the virus to propagate and infect a large number of people in a short time period. A multipronged response with an active role by the communities is critical for combating chikungunya and other emerging infectious diseases. The paper discusses important lessons that can be learned from the recent outbreaks of chikungunya fever in Asia.  相似文献   
88.
OBJECTIVE: Anti-RNA polymerase I/III (anti-RNAP I/III) antibodies are clinically useful markers of scleroderma, and their presence is associated with diffuse skin disease and an increased risk of cardiac and kidney involvement. Although RNAP I antibodies localize to the nucleolus, nucleolar staining by many anti-RNAP antibody-positive sera is not always observed. Nucleolar staining by anti-RNAP antibody-positive sera was examined by double staining with antifibrillarin antibodies to evaluate whether nucleolar staining can be used as a screening test for anti-RNAP I/III antibodies. In addition, the relationships between nucleolar staining and levels of anti-RNAP III antibodies were examined by enzyme-linked immunosorbent assay (ELISA) and immunoprecipitation (IP) assay. METHODS: Sera were tested using immunofluorescent antinuclear antibodies on HEp-2 cell slides, by anti-RNAP III ELISA, and by IP assay using (35)S-labeled K562 cell extract. Nucleolar staining by anti-RNAP antibody IP-positive sera was confirmed by double staining using antifibrillarin monoclonal antibodies. The levels of anti-RNAP III antibodies were quantitated by ELISA and by IP assay using a serially diluted reference serum as a standard, and their relationship was analyzed. RESULTS: All 18 anti-RNAP I/III antibody-positive sera showed nuclear speckled patterns, but nucleolar staining was readily noticeable in only 44% of the sera. A positive correlation was found between ELISA and IP units for anti-RNAP III antibodies. The levels of anti-RNAP III antibodies and anti-RNAP I antibodies correlated well, with the exception of a few sera. Levels of anti-RNAP III antibodies were low in sera with nucleolar staining, whereas several sera with high levels of anti-RNAP I antibodies clearly showed nucleolar staining. CONCLUSION: Although some sera positive for anti-RNAP I/III antibodies clearly stain nucleoli, nucleolar staining is inconsistent and cannot be used to screen for anti-RNAP I/III antibodies.  相似文献   
89.
An influenza pandemic due to influenza virus A H5N1 subtype is considered highly likely. Strategies for prevention and control of a pandemic include actions that need to be taken by the national authorities and communities. The availability of a vaccine and antiviral drugs in sufficient quantities for billions of people in the developing world is doubtful. Simple cost effective public health interventions can significantly reduce the risk of contracting infection. These interventions include precautions that will prevent people from contracting infection from sick or dying poultry and their products, human cases and a contaminated environment. Specific measures are based on principles of cutting short the transmission of infection in humans and inactivating the virus at its source. The paper describes context specific actions that can be implemented in both rural and urban settings by the communities themselves.  相似文献   
90.
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