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   1455507篇
  免费   105146篇
  国内免费   4718篇
耳鼻咽喉   18863篇
儿科学   46836篇
妇产科学   39228篇
基础医学   213843篇
口腔科学   40520篇
临床医学   137334篇
内科学   286893篇
皮肤病学   30277篇
神经病学   121846篇
特种医学   50889篇
外国民族医学   368篇
外科学   198078篇
综合类   29532篇
现状与发展   1篇
一般理论   496篇
预防医学   126412篇
眼科学   31614篇
药学   107486篇
  6篇
中国医学   3851篇
肿瘤学   80998篇
  2021年   14401篇
  2019年   14817篇
  2018年   20790篇
  2017年   14967篇
  2016年   15784篇
  2015年   18055篇
  2014年   24703篇
  2013年   37608篇
  2012年   52922篇
  2011年   56199篇
  2010年   32073篇
  2009年   28760篇
  2008年   49731篇
  2007年   52483篇
  2006年   51994篇
  2005年   50380篇
  2004年   47614篇
  2003年   45103篇
  2002年   43509篇
  2001年   63662篇
  2000年   65661篇
  1999年   54799篇
  1998年   15212篇
  1997年   13781篇
  1996年   13504篇
  1995年   12785篇
  1994年   11895篇
  1993年   11152篇
  1992年   42549篇
  1991年   41579篇
  1990年   40187篇
  1989年   37979篇
  1988年   35152篇
  1987年   34228篇
  1986年   32672篇
  1985年   31083篇
  1984年   23366篇
  1983年   19897篇
  1982年   11941篇
  1979年   21129篇
  1978年   15047篇
  1977年   12238篇
  1976年   12064篇
  1975年   12353篇
  1974年   15118篇
  1973年   14774篇
  1972年   13626篇
  1971年   12711篇
  1970年   11742篇
  1969年   10681篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
63.
64.
65.
French asthma patients may be supervised by general practitioners (GPs) and/or specialists. Therefore, this study examined asthma management in patients exclusively supervised by specialists (SPE), GPs, (GP) and both (GP+SPE group), and compared the findings. Asthma patients were consecutively recruited in 348 pharmacies. Each patient completed a questionnaire providing data on personal characteristics, asthma management, perception of disease and asthma supervision. Asthma control was measured using the Asthma Control Test. Questionnaires were linked to computerised records of medications which had been dispensed before inclusion in the study. From the 1,256 patients (mean age = 36.1 yrs, 54.3% females), 11.4, 36.6, and 52.0% were placed in the SPE, GP, and GP+SPE groups, respectively. During the previous 4 weeks, most patients in the SPE group were properly controlled (52.2 versus 26.4 and 21.5% in GP and GP+SPE groups, respectively). The SPE group made more use of fixed combinations of long-acting beta agonist and inhaled corticosteroid, while receiving less short-acting beta agonists, antitussives and antibiotics. Striking differences in symptoms and asthma management were observed according to the type of asthma supervision. The current results strongly support the need to improve the management of asthma in primary care, and the coordination of care between general practitioners and specialists.  相似文献   
66.
67.
Spinocerebellar ataxia (SCA) types 2 and 3 are autosomal-dominant neurodegenerative disorders caused by mutations in two different genes. We identified mutations for SCA2 and SCA3 segregating simultaneously in a single Brazilian family. The index patient had SCA2, whereas her two second-degree cousins had SCA3. Disease was more rapidly progressive in the SCA2 patient, who presented severe brainstem and pancerebellar atrophy, as opposed to the two SCA3 patients, who had only mild cerebellar vermian atrophy. In such situations, molecular confirmation of all patients may avoid misdiagnosis of SCA subtypes and eventual errors in predictive testing of unaffected family members.  相似文献   
68.
Research coordinators in intensive care are a growing specialty about which little is known. This cross-sectional study surveyed the Australia and New Zealand Intensive Care Research Coordinators' Group (n = 49) regarding demographics, education, employment history, job structure, and role content. Most research coordinators were highly qualified and experienced nurses who undertake pharmaceutical trials, multicenter projects, departmental medical and nursing research, audits and data registries, and their own projects.  相似文献   
69.
70.
Mucosal trypsin, a protease-activated receptor (PAR) stimulant, may have an endogenous bronchoprotective role on airway smooth muscle. To test this possibility the effects of lumenal trypsin on airway tone in segments of pig bronchus were tested. Bronchial segments from pigs were mounted in an organ chamber containing Kreb's solution. Contractions were assessed from isovolumetric lumen pressure induced by acetylcholine (ACh) or carbachol added to the adventitia. Trypsin, added to the airway lumen (300 microg x mL(-1)), had no immediate effect on smooth muscle tone but suppressed ACh-induced contractions after 60 min, for at least 3 h. Synthetic activating peptides (AP) for PAR1, PAR2 or PAR3 were without effect, but PAR4 AP caused rapid, weak suppression of contractions. Lumenal thrombin was without effect and did not prevent the effects of trypsin. Effects of trypsin were reduced by N(omega)-nitro-L-arginine methyl ester but not indomethacin. Trypsin, thrombin and PAR4 AP released prostaglandin E2. Adventitially, trypsin, thrombin and PAR4 AP (but not PAR2 AP) relaxed carbachol-toned airways after <3 min. The findings of this study show that trypsin causes delayed and persistent bronchoprotection by interacting with airway cells accessible from the lumen. The signalling mechanism may involve nitric oxide synthase but not prostanoids or protease-activated receptors.  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