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   1339194篇
  免费   112551篇
  国内免费   6379篇
耳鼻咽喉   16706篇
儿科学   43031篇
妇产科学   36555篇
基础医学   183691篇
口腔科学   36278篇
临床医学   120749篇
内科学   278779篇
皮肤病学   31894篇
神经病学   110505篇
特种医学   55544篇
外国民族医学   275篇
外科学   210550篇
综合类   31537篇
现状与发展   2篇
一般理论   414篇
预防医学   106644篇
眼科学   28098篇
药学   93720篇
  5篇
中国医学   2228篇
肿瘤学   70919篇
  2018年   13385篇
  2017年   10640篇
  2016年   12799篇
  2015年   14301篇
  2014年   19956篇
  2013年   29747篇
  2012年   36272篇
  2011年   38915篇
  2010年   24396篇
  2009年   23925篇
  2008年   36401篇
  2007年   38813篇
  2006年   39935篇
  2005年   38524篇
  2004年   36764篇
  2003年   35841篇
  2002年   33872篇
  2001年   66078篇
  2000年   67950篇
  1999年   56615篇
  1998年   16732篇
  1997年   15020篇
  1996年   16021篇
  1995年   16237篇
  1994年   15110篇
  1993年   14160篇
  1992年   47121篇
  1991年   45768篇
  1990年   43999篇
  1989年   41836篇
  1988年   38775篇
  1987年   38099篇
  1986年   35869篇
  1985年   34646篇
  1984年   26364篇
  1983年   22114篇
  1982年   13848篇
  1981年   12452篇
  1980年   11721篇
  1979年   23554篇
  1978年   17079篇
  1977年   14388篇
  1976年   13182篇
  1975年   13724篇
  1974年   16094篇
  1973年   15400篇
  1972年   14177篇
  1971年   13040篇
  1970年   11883篇
  1969年   11102篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
51.
There is increasing evidence that the assessment of eosinophilic airway inflammation using induced sputum and measurement of airway hyperresponsiveness provides additional, clinically important information concerning asthma control. The aim of this study was to directly compare the effects of different treatments on these markers in patients with asthma and persistent symptoms, despite the use of low-dose inhaled corticosteroids. A double-blind four-way crossover study was performed, which compared a 1-month treatment with budesonide 400 mug b.i.d., additional formoterol, additional montelukast and placebo in 49 patients with uncontrolled asthma despite budesonide 100 mug b.i.d., with each treatment separated by a 4-week washout period. The change in sputum eosinophil count with formoterol (2.4 to 3.8% change, 0.6-fold reduction, 95% confidence interval (CI) 0.5-0.9) differed significantly from placebo (2.8 to 2.5% change, 1.1-fold reduction, 95% CI 0.7-1.6) and high-dose budesonide (2.7 to 1.6% change, 1.6-fold reduction, 95% CI 1.2-2.2). The effects of montelukast did not differ from placebo. The changes in methacholine airway responsiveness were small and did not differ between treatments. High-dose budesonide had the broadest range of beneficial effects on other outcomes, including symptom scores, morning peak expiratory flow and forced expiratory volume in one second. In conclusion, treatment given in addition to low-dose inhaled corticosteroids results in modest benefits. Formoterol and high-dose budesonide have contrasting effects on eosinophilic airway inflammation.  相似文献   
52.
53.
54.
55.
56.
The aim of the present study was to explore differences in the clinical expression, clinical diagnoses and management of airway diseases in a primary-care setting. Patients aged >or=35 yrs who had ever smoked were enrolled when they presented for any reason to one of eight rural primary-care practices. Respiratory symptom questionnaires and spirometry were administered. In total, 1,034 patients had acceptable and reproducible spirometry, of whom 550 (53%) were males and 484 (47%) were females. Males smoked more than females (41.2 versus 29.2 pack-yrs) respectively, and were more likely to have a pre-bronchodilator forced expiratory volume in one second/forced vital capacity <0.70 at 22.4 versus 11.8%, respectively. However, more females than males reported breathlessness (51.0 versus 42.8%, respectively), a prior diagnosis compatible with airflow obstruction and taking respiratory medications (23.4 versus 14.9%, respectively). In conclusion, the current results suggest that females are more likely than males to report breathlessness and be prescribed respiratory medications independent of differences in the severity of airflow obstruction.  相似文献   
57.
58.
59.
60.
For many parents stopping life-sustaining medical treatment on their dying infant is psychologically impossible. Dostoevsky's insights into human behavior, particularly the fact that individuals do not want the anxiety and guilt associated with responsibility for making difficult decisions, might change the way physicians approach parents for permission to withdraw life-prolonging medical interventions on dying infants.  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