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   1254篇
  免费   56篇
  国内免费   1篇
  2023年   6篇
  2021年   15篇
  2020年   23篇
  2019年   25篇
  2018年   18篇
  2017年   42篇
  2016年   29篇
  2015年   22篇
  2014年   27篇
  2013年   127篇
  2012年   61篇
  2011年   53篇
  2010年   44篇
  2009年   37篇
  2008年   67篇
  2007年   62篇
  2006年   50篇
  2005年   57篇
  2004年   53篇
  2003年   37篇
  2002年   49篇
  2001年   17篇
  2000年   20篇
  1999年   16篇
  1998年   22篇
  1997年   19篇
  1996年   6篇
  1995年   15篇
  1994年   12篇
  1993年   17篇
  1992年   18篇
  1991年   19篇
  1990年   19篇
  1989年   15篇
  1988年   21篇
  1987年   10篇
  1986年   10篇
  1985年   17篇
  1984年   16篇
  1983年   12篇
  1982年   12篇
  1981年   17篇
  1980年   12篇
  1979年   8篇
  1978年   5篇
  1976年   6篇
  1975年   6篇
  1974年   7篇
  1968年   6篇
  1967年   5篇
排序方式: 共有1311条查询结果,搜索用时 390 毫秒
41.
Two experiments were conducted to investigate the relationship between dimensional integrality and the form of the combination rule or spatial metric used in a similarity judgment task. In Experiment 1, two groups of eight subjects judged the dissimilarity of all pairwise combinations of 12 rectangles differing in height and width (integral dimensions) or 12 circles differing in size and diameter orientation (separable dimensions). The dimensional organization and spatial metric of both sets of dimensions were determined. The results showed that differences in height and width contributed independently to judgments of the overall dissimilarity of rectangles and that these dimensions were combined using a Euclidean metric. In contrast, substantial interactions between circle size and diameter orientation were found. Combinations of these dimensions also appeared to violate the triangle inequality implying that no spatial metric was appropriate. In Experiment 2, parallelogram size and tilt were similarly analyzed. Although some degree of dimensional interaction was observed, it was found that on the average these dimensions were combined using a city-block metric. In a subsequent speeded classification task, orthogonal interference was observed, which suggested that size and tilt are integral dimensions. The implications of both experiments for the supposed association between the Euclidean metric and dimensional integrality are discussed.  相似文献   
42.
The purpose of the current study was to examine the agreement across three informants (youth, teacher, caretaker) when rating behaviors of incarcerated juvenile delinquents. Furthermore, the agreement between a dimensional approach (Child Behavior Checklist) and a categorical approach (DSM-III-R) of assessing behavior was examined. Fifty-two delinquent youth were assessed with a structured interview. In addition, the youth, teacher, and caretaker completed the Child Behavior Checklist (CBCL). The results indicated significant correlations across the teacher and caretaker for externalizing types of problems. The youth report form of the CBCL did not correspond to either adult informant. However, the ratings by the teacher and caretaker were related to externalizing types of problems, primarily hyperactivity/inattention, derived from the structured interview with the delinquent. The results suggest that, in the psychological assessment of incarcerated juvenile delinquents, agreement across informants is dependent on multiple factors, including type of behavior assessed and the approach utilized in assessment.This work was supported, in part, by the Juvenile Justice Coordinating Council of Georgia, the Office of Juvenile Justice and Delinquency Prevention, and the University of Georgia's Institute for Behavioral Research.  相似文献   
43.
44.
There is a lack of consistency in findings regarding subject (S) characteristics and the effects of smoking-control programmes. Research workers appear to assume that abstinence and reduction in smoking rate are merely different points in the same continuum, and therefore seek to correlate S variables with percentage reductions in smoking rate. It is argued that abstinence and reduced smoking are more appropriately viewed as potentially discrete outcomes. Conceptualizing outcome in this manner, a discriminant function analysis was employed to determine whether it is possible to differentiate between Ss who do, or do not, abstain following participation in a treatment programme involving rapid-smoking. It was found that it is possible to discriminate between the two groups of Ss. Advantages deriving from this approach to the investigation of S characteristics and treatment outcome are discussed.  相似文献   
45.
Past research has suggested that proportionally more superordinate than sub-ordinate propositions are recalled from expository texts, following a hierarchical analysis of the text structure. Since free recall has typically followed this hierarchical pattern, several researchers have assumed that the related memory structures are isomorphic to the text structure. However, few of these studies have examined how individual differences and text structure interact to affect free recall. In two experiments, the assumption of hierarchical patterns of children's recall of expository text was tested. In Experiment 1, high- and average-ability fourth graders (9 years old) were asked to read and recall a passage. Experiment 2 was a replication and extension of Experiment 1. In this experiment, fourth and sixth graders (9 and 11 years old) read and recalled a different passage. The combined results of both experiments support the notion that there is probably no one optimal hierarchical structure for storage and retrieval of expository text.  相似文献   
46.
In this paper two different formulations of Robinson's arithmetic based on relevant logic are examined. The formulation based on the natural numbers (including zero) is shown to collapse into classical Robinson's arithmetic, whereas the one based on the positive integers (excluding zero) is shown not to similarly collapse. Relations of these two formulations to R. K. Meyer's system R# of relevant Peano arithmetic are examined, and some remarks are made about the role of constant functions (e.g., multiplication by zero) in relevant arithmetic.This paper has been greatly influenced by the (largely unpublished) work of E. K. Meyer (cf. [7]) on relevant arithmetic, and I wish to thank him, and also N. D. Belnap, Jr. and D. Cohen for helpful advice. In fairness to Meyer it must be said that he finds my axioms 13 and 13(1) too strong (they are not theorems of his system R# - cf. §4 below). Meyer tells me be finds vindication for his view in my chief theorem of §2. For myself, I find the insights behind Meyer's work on R# to be both stable and fruitful, and if I now had to make a choice, I would follow Meyer in his rejection of my axioms. However, the systems I explore in this paper themselves have a surprising amount of internal consistency of motivation (cf. §5). Let a hundred formal systems bloom.  相似文献   
47.
Given classical (2 valued) structures and and a homomorphism h of onto , it is shown how to construct a (non-degenerate) 3-valued counterpart of . Classical sentences that are true in are non-false in . Applications to number theory and type theory (with axiom of infinity) produce finite 3-valued models in which all classically true sentences of these theories are non-false. Connections to relevant logic give absolute consistency proofs for versions of these theories formulated in relevant logic (the proof for number theory was obtained earlier by R. K. Meyer and suggested the present abstract development).  相似文献   
48.
49.
OBJECTIVE: Fibromyalgia (FM) syndrome is a chronic pain condition characterized by diffuse muscle pain, increased negative mood, and sleep disturbance. Until recently, sleep disturbance in persons with FM has been modeled as the result of the disease process or its associated pain. The current study examined sleep disturbance (i.e., sleep duration and sleep quality) as a predictor of daily affect, stress reactivity, and stress recovery. DESIGN AND MEASURES: A hybrid of daily diary and ecological momentary assessment methodology was used to evaluate the psychosocial functioning of 89 women with FM. Participants recorded numeric ratings of pain, fatigue, and positive and negative affect 3 times throughout the day for 30 consecutive days. At the end of each day, participants completed daily diary records of positive and negative life events. In addition, participants reported on their sleep duration and sleep quality each morning. RESULTS: After accounting for the effects of positive events, negative events, and pain on daily affect scores, it was found that sleep duration and quality were prospectively related to affect and fatigue. Furthermore, the effects of inadequate sleep on negative affect were cumulative. In addition, an inadequate amount of sleep prevented affective recovery from days with a high number of negative events. CONCLUSIONS: These results lend support to the hypothesis that sleep is a component of allostatic load and has an upstream role in daily functioning.  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