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   998249篇
  免费   75279篇
  国内免费   2621篇
耳鼻咽喉   12967篇
儿科学   34490篇
妇产科学   28634篇
基础医学   145354篇
口腔科学   27736篇
临床医学   90315篇
内科学   193731篇
皮肤病学   22927篇
神经病学   79137篇
特种医学   38410篇
外国民族医学   306篇
外科学   149600篇
综合类   23755篇
一般理论   385篇
预防医学   77854篇
眼科学   22619篇
药学   71905篇
  3篇
中国医学   2031篇
肿瘤学   53990篇
  2018年   10587篇
  2017年   8253篇
  2016年   9389篇
  2015年   10611篇
  2014年   14444篇
  2013年   22043篇
  2012年   29043篇
  2011年   30891篇
  2010年   18517篇
  2009年   17457篇
  2008年   28823篇
  2007年   30506篇
  2006年   31008篇
  2005年   29684篇
  2004年   28959篇
  2003年   27832篇
  2002年   26844篇
  2001年   46944篇
  2000年   48059篇
  1999年   40276篇
  1998年   11182篇
  1997年   10103篇
  1996年   10163篇
  1995年   9779篇
  1994年   9091篇
  1993年   8483篇
  1992年   32265篇
  1991年   31468篇
  1990年   31013篇
  1989年   29888篇
  1988年   27174篇
  1987年   27332篇
  1986年   25444篇
  1985年   24606篇
  1984年   18399篇
  1983年   15519篇
  1982年   9288篇
  1981年   8375篇
  1979年   16860篇
  1978年   12218篇
  1977年   10314篇
  1976年   9754篇
  1975年   10179篇
  1974年   12321篇
  1973年   11849篇
  1972年   10888篇
  1971年   10121篇
  1970年   9381篇
  1969年   8730篇
  1968年   8107篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
992.
The original article to which this Erratum refers was published in Pharmacoepidemiology and Drug Safety 2005; 14: 239–247.  相似文献   
993.
Secondary prevention of coronary events in coronary artery disease (CAD) patients with aspirin is generally accepted because of ease of administration, predictable safety, and proven efficacy. The use of long-term anticoagulant therapy with heparins, vitamin-K antagonists (VKAs), or thrombin inhibitors is, however, more controversial. During the last 40 years, several trials have been conducted in order to evaluate the role of anticoagulant therapy in patients with CAD as a protection against subsequent death and thrombo-embolic complications. The conducted trials are heterogeneous in many ways, concerning comparative medications, patient populations, endpoints and follow-up, which makes a standardized recommendation on the basis of these studies difficult. This review is an overview of the largest and best studies on this topic and discusses the scientific background for a possible use of VKA or an alternative anticoagulant treatment in CAD patients, looking at both the beneficial effects and the risk of bleeding.  相似文献   
994.
995.
996.
The endotoxin receptor soluble CD14 (sCD14) has been implicated in the 'hygiene hypothesis' suggesting reduced allergic sensitization with bacterial stimulation. However, the relationship between early life sCD14 and allergic diseases is conflicting. We aimed to investigate whether possible risk factors for allergic diseases were associated with sCD14 levels at 2 yr of age. In the nested case-control study of the birth cohort studies 'Environment and Childhood Asthma study in Oslo' 411 children selected with recurrent bronchial obstruction (rBO) (n=241) and no bronchial obstruction (n=170) by 2 yr were investigated with skin prick test and structured parental interview at age 2 yr. Exposure to tobacco smoke, pets and infections was recorded semi-annually by questionnaires (0-2 yr). The sCD14 was analysed from frozen, stored serum by ELISA technique. Regression analyses were performed in all subjects with complete data (n=406, 180 girls), and in girls and in boys separately. Mean sCD14 (ng/ml) was significantly higher among girls 2035 (1973-2096) vs. 1947 (1890-2004) (boys). The sCD14 was significantly reduced among girls exposed to antenatal maternal smoking and with parental asthma, after adjusting for age, parental rhino-conjunctivitis, pet keeping and childhood infections. Recurrent otitis media (OM) increased and common colds significantly decreased sCD14 levels in girls. Boys with atopic dermatitis and rBO had reduced sCD14. Pet exposure was not significantly associated with sCD14. We report novel gender-related effects of sCD14 in early life and suggest that gender, tobacco smoke exposure, age and middle ear disease in particular should be accounted for when assessing the role of sCD14 in childhood allergic diseases.  相似文献   
997.
998.
999.
1000.
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