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   1501527篇
  免费   128442篇
  国内免费   17450篇
耳鼻咽喉   18424篇
儿科学   45221篇
妇产科学   37898篇
基础医学   198406篇
口腔科学   39107篇
临床医学   140661篇
内科学   298405篇
皮肤病学   33781篇
神经病学   116880篇
特种医学   61673篇
外国民族医学   342篇
外科学   227014篇
综合类   67338篇
现状与发展   51篇
一般理论   424篇
预防医学   120595篇
眼科学   31749篇
药学   111071篇
  200篇
中国医学   15353篇
肿瘤学   82826篇
  2021年   16355篇
  2019年   13762篇
  2018年   18470篇
  2017年   15811篇
  2016年   17703篇
  2015年   22008篇
  2014年   29353篇
  2013年   39516篇
  2012年   50353篇
  2011年   54061篇
  2010年   35891篇
  2009年   33508篇
  2008年   47104篇
  2007年   49041篇
  2006年   49528篇
  2005年   46660篇
  2004年   42487篇
  2003年   41225篇
  2002年   38297篇
  2001年   69384篇
  2000年   70483篇
  1999年   58535篇
  1998年   17863篇
  1997年   16100篇
  1996年   16869篇
  1995年   17006篇
  1994年   15686篇
  1993年   14522篇
  1992年   47464篇
  1991年   46043篇
  1990年   44231篇
  1989年   42020篇
  1988年   38929篇
  1987年   38258篇
  1986年   35988篇
  1985年   34733篇
  1984年   26410篇
  1983年   22147篇
  1982年   13877篇
  1981年   12480篇
  1979年   23583篇
  1978年   17088篇
  1977年   14401篇
  1976年   13198篇
  1975年   13734篇
  1974年   16113篇
  1973年   15423篇
  1972年   14182篇
  1971年   13043篇
  1970年   11889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