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   6755篇
  免费   406篇
  国内免费   11篇
耳鼻咽喉   45篇
儿科学   267篇
妇产科学   136篇
基础医学   735篇
口腔科学   106篇
临床医学   1459篇
内科学   1130篇
皮肤病学   62篇
神经病学   516篇
特种医学   120篇
外科学   561篇
综合类   76篇
一般理论   9篇
预防医学   878篇
眼科学   83篇
药学   345篇
中国医学   1篇
肿瘤学   643篇
  2024年   5篇
  2023年   36篇
  2022年   60篇
  2021年   121篇
  2020年   76篇
  2019年   90篇
  2018年   141篇
  2017年   107篇
  2016年   120篇
  2015年   131篇
  2014年   223篇
  2013年   323篇
  2012年   480篇
  2011年   568篇
  2010年   297篇
  2009年   262篇
  2008年   484篇
  2007年   560篇
  2006年   520篇
  2005年   534篇
  2004年   495篇
  2003年   453篇
  2002年   462篇
  2001年   43篇
  2000年   25篇
  1999年   63篇
  1998年   56篇
  1997年   55篇
  1996年   49篇
  1995年   41篇
  1994年   44篇
  1993年   31篇
  1992年   28篇
  1991年   25篇
  1990年   18篇
  1989年   11篇
  1988年   9篇
  1987年   13篇
  1986年   8篇
  1985年   10篇
  1984年   21篇
  1983年   12篇
  1982年   18篇
  1981年   11篇
  1980年   19篇
  1979年   2篇
  1978年   3篇
  1976年   2篇
  1975年   3篇
  1971年   1篇
排序方式: 共有7172条查询结果,搜索用时 0 毫秒
1.
2.
3.
CONTEXT: The limited information available on the oral health status of rural children in the United States makes it difficult to devise policy strategies to address perceived problems. PURPOSE: To document the oral health status and dental care utilization of US children by place of residence, METHODS: Data from National Health Interview Surveys for 1995, 1997, and 1998, and from the third National Health and Nutrition Examination Survey (1988-1994) were analyzed. FINDINGS: Children residing in rural areas were more likely to be uninsured for dental care than were children from urban areas (41.1% versus 34.7%). A greater percentage of rural than urban children reported unmet dental needs (7.5% versus 5.6%); there was no difference in self-reported poor dental status. Urban children were more likely than rural children to have visited the dentist in the past year (73.6% versus 69.9%) and were also more likely to be regular users of dental care (61.7% versus 51.4%). Differences in percentage of rural and urban children with caries lesions and caries experience were not significant. CONCLUSIONS: Children residing in rural areas have less access to and utilization of dental care compared to children residing in urban areas. Moreover, poor rural children display less utilization of dental services than poor urban children. Differences in the sum of decayed and filled primary teeth and the sum of decayed, missing, and filled permanent teeth were not significant.  相似文献   
4.
‘Wandering’ is one of the most troublesome of behavioural problems in dementia. The term ‘wandering’ covers many different types of behaviour. We examined the hypothesis that the different types of wandering behaviour seen in dementia from a scale using data collected on 83 elderly subjects suffering from either Alzheimer's disease or multiinfarct dementia. We reject the scaling hypothesis. Our data suggest that there are three main categories of wandering behaviour, and that one of these categories is usefully divided into four subcategories.  相似文献   
5.
6.
7.
The objective of this study was to use the Lille Apathy Rating Scale to assess apathy in a large population of Parkinson's disease (PD) patients and identify several different apathy profiles. One hundred fifty-nine patients with probable PD and 58 healthy controls participated in the study. Apathy was assessed using the Lille Apathy Rating Scale. Motor, cognitive, and depressive symptoms were rated on standardized scales. Data were analyzed using linear regression and multivariate analyses of variance. Thirty-two percent of the PD patients were classified as apathetic. Apathy was more frequent in patients with dementia. The four apathy dimensions contributed differently to the overall severity of the apathetic condition. Action initiation and intellectual curiosity had a marked influence. Linear regression analysis revealed that the apathy level was mainly determined by cognitive impairment, not associated with the severity of motor symptoms, and only associated with the apathy subcomponent of the Montgomery and Asberg Depression Rating Scale. Apathy is highly prevalent in PD patients. Apathy profiles vary according to the clinical presentation of PD. The high prevalence of apathy in PD suggests the involvement of frontal-subcortical circuits. Although the neurochemical substrate of apathy remains poorly characterized, the strong link between apathy and cognitive impairment observed in several studies suggests the participation of nondopaminergic circuits.  相似文献   
8.
9.
10.
大多数药物注射包部件(例如针头、注射器、活塞和瓶等)都要求采用某些形式的表面处理或润滑,以便改善其操作性和功能性。本文综述了硅烷化使用的材料和工艺,以及在其后对硅烷化制品的消毒和硅油的清除。  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