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   827篇
  免费   94篇
  国内免费   3篇
耳鼻咽喉   3篇
儿科学   23篇
妇产科学   7篇
基础医学   134篇
口腔科学   7篇
临床医学   96篇
内科学   74篇
皮肤病学   3篇
神经病学   233篇
特种医学   11篇
外科学   15篇
综合类   38篇
预防医学   173篇
眼科学   4篇
药学   83篇
中国医学   9篇
肿瘤学   11篇
  2023年   14篇
  2022年   8篇
  2021年   36篇
  2020年   36篇
  2019年   54篇
  2018年   37篇
  2017年   39篇
  2016年   40篇
  2015年   39篇
  2014年   48篇
  2013年   119篇
  2012年   44篇
  2011年   41篇
  2010年   37篇
  2009年   36篇
  2008年   36篇
  2007年   40篇
  2006年   44篇
  2005年   25篇
  2004年   23篇
  2003年   28篇
  2002年   20篇
  2001年   15篇
  2000年   13篇
  1999年   8篇
  1998年   9篇
  1997年   6篇
  1996年   4篇
  1995年   5篇
  1994年   1篇
  1993年   5篇
  1991年   5篇
  1990年   3篇
  1989年   1篇
  1988年   3篇
  1984年   1篇
  1983年   1篇
排序方式: 共有924条查询结果,搜索用时 599 毫秒
1.
Background: Most theoretical models of self-determination suggest that both environmental and personal factors influence the development of self-determination. The design and implementation of interventions must be conducted with foreknowledge of such mediating and moderating factors if the intervention is to be successful.

Methods: The purpose of this study was to examine the degree to which several personal factors and school characteristics affect and explain students’ self-determination. A total of 232 students with intellectual disability from Spain participated. Their self-determination level was assessed by the ARC-INICO Scale.

Results: Students with moderate levels of intellectual disability obtained significantly lower scores on self-determination than their peers with mild intellectual disability. There were significant differences in relation to the level of support needs and their experience with transition programs. The level of support needs was a significant predictor.

Conclusion: These findings contribute to current research in this field and practical implications were discussed.  相似文献   

2.
Abstract: Data from the National Education Longitudinal Study were combined with census data at the zip code level to examine the impact of neighborhood racial and ethnic diversity and consolidated inequality, in addition to individual, family, and school factors, on the likelihood of dropping out of high school. Results indicate that while the effects for diversity and consolidated inequality did not support the stated hypotheses, main effects for family risk and prior academic achievement were significant and in the stated direction. Also, when controlling for individual, family, school, and neighborhood characteristics, African Americans were less likely than White students to drop out of school. Implications for contextual effects research and educational outcomes are discussed.  相似文献   
3.
While much time has been spent deliberating about the definition of play, little emphasis has been placed on what children themselves perceive as play. The aim of the present study was to examine social context as a cue for children's perceptions of play and learning. Ninety-two children aged between four and six years (mean four years nine months) participated in the study and completed the Activity Apperception Story Procedure. Children were asked to sort photographic stimuli into those they believed depicted play/not play and learning/not learning. Each of the stimuli were identified by independent raters as containing one of the following social cues; teacher absence (solitary activity, parallel activity or cooperative activity) or teacher presence (teacher involved activity or teacher directed activity). Findings revealed that children associated teacher absence with play. More specifically, children made links between play and the presence of peers (parallel and cooperative activity). Findings are discussed in relation to play in the early years curriculum, differences in children's early educational experiences and the importance of understanding children's perceptions of play.  相似文献   
4.
Research on children's early writing development in the past has focused primarily on product and process. In reviewing the more recent research on early writing development, however, a new focus of context emerges. Occurrences of literacy are now being observed in the home, the school, and the community. With this new emphasis, comes the task of defining context. A definition of context reflects theoretical perspectives, areas of research interests, and types of methodologies employed in conducting research. Therefore, the purpose of this article is to address the following aspects of context: #op1#cp multidiscipline perspectives and definitions of context, #op2#cp contextual shifts observed between the home and the school, #op3#cp contextual factors present when learning how to write, and #op4#cp pedagogical implications for curriculum development.  相似文献   
5.
目的:探讨Antonovsky开发的13个项日的心理一致感量表在中国大陆的适用性。方法:采用实证研究方式对656名被试的样本数据进行了探索性及验证性因索分析,结果:个体的心理一致感是由可理解性、易处理性及意义性三个成分构成的总体.支持Antonovsky提出的关于心理一致感的要念构思。结论:心理一致感量表对中国大陆样本基本上是适用的,但个别题目有待进一步修正。  相似文献   
6.
7.
In the primate striatum, the tonically discharging neurons respond to conditioned stimuli associated with reward. We investigated whether these neurons respond to the reward itself and how changes in the behavioral context in which the reward is delivered might influence their responsiveness. A total of 286 neurons in the caudate nucleus and putamen were studied in two awake macaque monkeys while liquid reward was delivered in three behavioral situations: (1) an instrumental task, in which reward was delivered upon execution of a visually triggered arm movement; (2) a classically conditioned task, in which reward was delivered 1 s after a visual signal; (3) a free reward situation, in which reward was delivered at irregular time intervals outside of any conditioning task. The monkeys′ uncertainty about the time at which reward will be delivered was assessed by monitoring their mouth movements. A larger proportion of neurons responsive to reward was observed in the free reward situation (86%) than in the classically conditioned (57%) and instrumental tasks (37%). Among the neurons tested in all situations (n = 78), 24% responded to reward regardless of the situation and 65% in only one or two situations. Responses selective for one particular situation occurred exclusively in the free reward situation. When the reward was delivered immediately after the visual signal in the classically conditioned task, most of the neurons reduced or completely lost their responses to reward, and other neurons remained responsive. Conversely, neuronal responses invariably persisted when reward was delivered later than 1 s after the visual signal. This is the first report that tonic striatal neurons might display responses directly to primary rewards. The neuronal responses were strongly influenced by the behavioral context in which the animals received the reward. An important factor appears to be the timing of reward. These neurons might therefore contribute to a general aspect of behavioral reactivity of the subject to relevant stimuli. Received: 16 September 1996 / Accepted: 1 April 1997  相似文献   
8.
The experiment investigated the effects in healthy volunteers of a single dose of temazepam (30 mg, oral) on effortful and automatic processing, by measuring memory for information and its context. Effortful processing was impaired, as shown by significant impairments in free recall of an 18-item list, but automatic processing was spared, as evidenced by no impairments in recall of the frequency of presentation, the colour, size or form of the items. In a second task, temazepam significantly impaired both recognition and recency memory of 30 items, although these scores were not correlated. Temazepam caused significant sedation, measured by an objective test and by subjective ratings, but this did not correlate with the memory impairments. The pattern of results is discussed with reference to the hypothesis that the memory impairments resulting from benzodiazepines are due to a reduction in information processing resources and thus affect effortful processing more than automatic processing.  相似文献   
9.
基于薄板样条和形状内容的医学图像非刚性配准方法研究   总被引:2,自引:0,他引:2  
目的 针对医学图像非刚性点配准的现状,给出一种基于点特征的非刚性配准方法.方法 利用一种新的相似度测量方法--形状内容来解决两幅图像中点的对应关系,并利用点对应关系来估计非刚性映射函数.结果 利用薄板样条实现了医学图像的快速准确非刚性配准.结论 实验结果表明,上述方法获得了很好的配准效果.  相似文献   
10.
The features of the urban environment can support human health as well as harm it, but less is known about such influences in the context of middle eastern countries. The association between green space and the political classifications of the urban environment and the risk of chronic illness was investigated in a novel setting, the twin cities of Ramallah and Albireh in the occupied Palestinian territory. We used a generalised multi-level regression analysis to link the 2017 census data with Geographic Information System data. We modelled individuals at level one (n = 54693) and areas of residence at level two (n = 228), adjusting for individual demographic and socio-economic characteristics.The proportions of ‘mixed’ trees in residential areas had a significant inverse association with the risk of chronic illness. On the political dimension, only living in a refugee camp had a significant positive association with chronic illness; however, this was largely explained and rendered non-significant when green space variables were entered into the models. Our ability to differentiate between several types of green space was important, as findings demonstrated that not all types were associated with reduced risk of chronic illness. Our results from a middle eastern setting add to the largely Western existing evidence, that trees in urban settings are important and beneficial to human health. Researchers and policymakers should pay more attention to the health consequences of refugee camps but also the role of trees in benefiting individuals' health in such a disadvantaged context.  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