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   8953篇
  免费   448篇
  2023年   63篇
  2022年   47篇
  2021年   97篇
  2020年   195篇
  2019年   203篇
  2018年   280篇
  2017年   286篇
  2016年   343篇
  2015年   253篇
  2014年   250篇
  2013年   1079篇
  2012年   469篇
  2011年   529篇
  2010年   300篇
  2009年   346篇
  2008年   405篇
  2007年   433篇
  2006年   380篇
  2005年   341篇
  2004年   332篇
  2003年   354篇
  2002年   288篇
  2001年   144篇
  2000年   140篇
  1999年   147篇
  1998年   147篇
  1997年   116篇
  1996年   111篇
  1995年   108篇
  1994年   114篇
  1993年   96篇
  1992年   90篇
  1991年   64篇
  1990年   68篇
  1989年   40篇
  1988年   38篇
  1987年   48篇
  1986年   47篇
  1985年   51篇
  1984年   57篇
  1983年   63篇
  1982年   57篇
  1981年   43篇
  1980年   42篇
  1979年   51篇
  1978年   50篇
  1977年   36篇
  1976年   40篇
  1973年   19篇
  1972年   18篇
排序方式: 共有9401条查询结果,搜索用时 15 毫秒
101.
This investigation focused on the interrelationships among students' study activities, students' self-concept of academic ability ratings, students' academic achievement, and instructional practices in 12 high school biology courses. Using a framework derived from a previous investigation, course features were classified into those that appear to (a) place demands on, (b) support, or (c) compensate for student engagement in particular study activities. Students' study activities, self-concept of academic ability ratings, and achievement were measured with experimenter-developed instruments. Results are reported for (a) characteristics of instruments and course features, (b) relationships between central factors of the investigation, and (c) multi-level relationships between course features and student variables. Results at the student level indicated that self-concept of academic ability and, to a lesser extent, students' study activities were positively associated with student achievement. Students' self-concept of academic ability ratings were also linked to students' engagement in generative, proactive study activities. At the course level the supportive practices of providing challenging homework assignments and extensive feedback on student coursework were associated with student engagement in effortful, generative, proactive study activities. The provision of extensive feedback was also associated with high student achievement. Multi-level relationships were analysed using hierarchical linear modelling (HLM) analyses. These analyses revealed, for example, that in courses in which little or no feedback is given on homework assignments, the relationship between achievement and student engagement in diligent effort management activities was enhanced. Other HLM analyses were conducted to examine the mediating role of course features on the relationship between students' self-concept of academic ability and their study activities and achievement. For example, the presence of challenging course demands was associated with an enhancement of the relationship between self-concept of academic ability and achievement whereas the presence of instructor provisions (supports and compensations) designed to reduce course demands was associated with a reduction in this relationship.  相似文献   
102.
103.
104.
Subjects wielded occluded rods, with or without attached masses, and reported the distances reachable with their distal tips. Experiments 1–3 compared wielding about the wrist, the elbow, and the shoulder. Experiments 4 and 5 compared free wielding, using the whole arm, with wielding only about the wrist. The two comparisons, respectively, were of spatial and temporal variations in the rod’s rotational inertia. Perceived extent was found to be constant in both comparisons. This constancy was tied to the inertia tensorI ij defined about a point that remains a fixed distance from the object during wielding—an invariant of the spatially and temporally dependent patterning of mechanical energy impressed upon the tissues of the body. Discussion focused on the reciprocal action and perception capabilities of multisegmented limbs, the tensorial relations in the neurobiology of dynamic touch, and the strategy of understanding perceptual constancy through invariants.  相似文献   
105.
A proximal-distal theoretical framework was developed to examine the multivariate roots of homophobia. Using data from a sample of 288 undergraduates who had participated in a computer-assisted panel study over a three-year period, the effects on homophobia of distal and proximal family factors (e. g., parental education and family environment), distal and proximal individual factors (e. g., personality constructs and current beliefs), and proximal individual-situational factors (e. g., acquaintance with homosexuals) were tested in regression analyses. Both analyses employing sets of variables varying in proximity to the homophobic attitude and hierarchical regression employing variables contributing significantly in each set supported the proposed framework. All sets predicted significantly when regressed separately on homophobia; the sets containing the distal factors contributed most weakly, and the sets containing the proximal factors contributed most strongly. In hierarchical regression analysis, this pattern maintained such that the incremental increase in r2 decreased with the addition of each more distal set, with the most distal factors failing to contribute significantly to the prediction. The importance of study findings for attitude change efforts is discussed.  相似文献   
106.
107.
Eight children with developmental language impairment (LI) and eight age-, sex-, socioeconomic-status-, and I.Q.-matched controls were given tests of comprehension and expression of affective intent in spoken language and through facial expression. The LI children performed significantly more poorly than did controls in both comprehension and spontaneous expression of vocal affect. On tasks involving emotional facial expression, the opposite results were observed: The LI children were more dramatic in their expression of facial affect than were the controls. Children with language impairment appear to have a deficit in affective comprehension and expression that is modality-specific, i.e., limited to vocal affect. The heightened range of affective facial expression that they demonstrate may be a compensatory mechanism to offset their difficulties with vocal affect.This work was supported by grant 12-203 from the March of Dimes Birth Defects Foundation, and by NINDS grant NS22343 for the Center for the Study of the Neurological Basis of Language.  相似文献   
108.
109.
110.
The strict competence hypothesis has sparked a small dialogue among several researchers attempting to understand its ramifications for human sentence processing and incremental interpretation in particular. In this paper, we review the dialogue, reconstructing the arguments in an attempt to make them more uniform and crisp, and provide our own analyses of certain of the issues that arise. We argue that strict competence, because it requires a synchronous computation mechanism, may actually lead to more complex, rather than simpler, models of incremental interpretation. Asynchronous computation, which is arguably both psychologically more plausible and conceptually more basic, allows for incremental interpretation to fall out naturally, without additional machinery for interpreting partial constituents. We show that this is true regardless of whether the presumed interpretation mechanism is top-down or bottom-up, contra previous conclusions in the literature, and propose a particular implementation of some of these ideas using a novel representation based on tree-adjoining grammars.The research in this paper was supported in part by grant IRI-9157996 from the National Science Foundation to the first author. The authors would like to thank Fernando Pereira, Edward Stabler, and Mark Steedman for discussions on the topic of this paper and for their comments on previous drafts.  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