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   36620篇
  免费   1964篇
  国内免费   109篇
耳鼻咽喉   455篇
儿科学   2140篇
妇产科学   737篇
基础医学   4656篇
口腔科学   818篇
临床医学   2584篇
内科学   7391篇
皮肤病学   843篇
神经病学   1982篇
特种医学   846篇
外科学   5099篇
综合类   1349篇
一般理论   15篇
预防医学   2140篇
眼科学   1566篇
药学   3531篇
中国医学   276篇
肿瘤学   2265篇
  2023年   243篇
  2022年   683篇
  2021年   1189篇
  2020年   656篇
  2019年   878篇
  2018年   1069篇
  2017年   734篇
  2016年   970篇
  2015年   1014篇
  2014年   1367篇
  2013年   1780篇
  2012年   2458篇
  2011年   2497篇
  2010年   1403篇
  2009年   1253篇
  2008年   1817篇
  2007年   1790篇
  2006年   1803篇
  2005年   1432篇
  2004年   1418篇
  2003年   1219篇
  2002年   1034篇
  2001年   835篇
  2000年   878篇
  1999年   740篇
  1998年   313篇
  1997年   217篇
  1996年   226篇
  1995年   221篇
  1994年   181篇
  1993年   152篇
  1992年   500篇
  1991年   407篇
  1990年   433篇
  1989年   399篇
  1988年   357篇
  1987年   356篇
  1986年   348篇
  1985年   323篇
  1984年   262篇
  1983年   219篇
  1979年   230篇
  1978年   148篇
  1977年   180篇
  1976年   140篇
  1975年   172篇
  1974年   182篇
  1973年   183篇
  1972年   173篇
  1971年   161篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
43.
44.
Estimation of plasma cortisol by fluorometric technique desorbed by Mallingly's was carried out in 56 cases, including 38 cases of myopia (19 cases of simple myopia and 19 cases of degenerative myopia) and 18 normal individuals. Urinary 17-keto steroids/24 hours was also estimated by Zimmermann technique in 12 out of the 56 cases, which include 8 cases of myopia (4 cases of simple myopia and 4 cases of degenerative myopia) and 4 normal individuals as control. Plasma cortisol level is lower in simple and degenerative myopia than in normal subjects, but on statistical analysis the difference was not of much significance. Patients with simple myopia with positive family history showed lower value of plasma cortisol than patients with simple myopia with negative family history, the difference was also statistically insignificant (P-0.1). In degenerative myopia patients, with and without family history, there was very little difference in plasma cortisol level and statistically highly insignificant (P-0.8). Urinary 17 keto steroid/24 hour values are lower in simple and degenerative myopia than in normal subjects.  相似文献   
45.
46.
The natural history of occult spinal dysraphism in children is one of progressive and unpredictable neurological deficit. The modern role of neurosurgery is in the prevention of deterioration rather than correction of established disability. A prospective study was carried out on 40 consecutive patients to analyse the referral pattern of children with this condition. The age, reason for referral, clinical history and source of referral was recorded in each case. The reason for referral varied with age. Of the 40 patients studied, only 12 were found to be without neurological deficit at the time of referral. The incidence of progressive neurological deterioration increased with increasing age. The referral source in different age groups varied, but in all age groups relatively few were referred by the general paediatricians or paediatric neurologists. For optimum surgical results, early referral and treatment is desirable and should become our objective.  相似文献   
47.
Summary Data are presented on rates of admission for schizophrenia for the native born and the four largest foreign born populations living in England in 1981 (Irish, Indian, Pakistani and Caribbean born). These data show that, in general, the foreign born have higher rates of admission for schizophrenia, and a higher proportion of all diagnoses accounted for by this disorder than do the native born. The exception is Pakistani born women who have conspicuously low rates. Five hypotheses are examined to account for these differences. The apparently high rates of schizophrenia found for the Indian born of both sexes, and Pakistani born men can be accounted for to a large extent by the demographic differences that exist between them and the native born. The Irish born residents of England have rates comparable with the Irish in Ireland who also show much higher rates than do the native English. There is no completely satisfactory account for the very high rates found for Caribbean born men and women but a combination of adverse post migration experiences and tendency to misdiagnose schizophrenia in this group is offered as a tentative explanation for at least some of the excess. The low rates of admission for schizophrenia of Pakistani women is attributed to a tendency on their part to opt out of the formal mental health system after an initial encounter, possibly to return to their native land.  相似文献   
48.
49.
In the present study 108 full time workers employed in various sections of a railway workshop and exposed to smoke and irritant fumes, and 45 matched control subjects from local administrative staff were investigated to find prevalence of chronic bronchitis. In all 18 (16.7%) workers and 4 (8.9%) control subjects had clinical evidence of chronic bronchitis. Peak expiratory flow rate less than 300 L/min was observed in 54.6% workers and 2.2% control subjects. A significantly higher prevalence of chronic bronchitis was seen in workers. The advancing age, smoking and duration of exposure had significant influence on prevalence of chronic bronchitis.  相似文献   
50.
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