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931.
A wealth of data demonstrating that monkeys and apes represent number have been interpreted as suggesting that sensitivity to number emerged early in primate evolution, if not before. Here we examine the numerical capacities of the mongoose lemur (Eulemur mongoz), a member of the prosimian suborder of primates that split from the common ancestor of monkeys, apes and humans approximately 47–54 million years ago. Subjects observed as an experimenter sequentially placed grapes into an opaque bucket. On half of the trials the experimenter placed a subset of the grapes into a false bottom such that they were inaccessible to the lemur. The critical question was whether lemurs would spend more time searching the bucket when food should have remained in the bucket, compared to when they had retrieved all of the food. We found that the amount of time lemurs spent searching was indicative of whether grapes should have remained in the bucket, and furthermore that lemur search time reliably differentiated numerosities that differed by a 1:2 ratio, but not those that differed by a 2:3 or 3:4 ratio. Finally, two control conditions determined that lemurs represented the number of food items, and neither the odor of the grapes, nor the amount of grape (e.g., area) in the bucket. These results suggest that mongoose lemurs have numerical representations that are modulated by Webers Law. 相似文献
932.
933.
934.
The Children's Attributional Style Interview: Developmental Tests of Cognitive Diathesis-Stress Theories of Depression 总被引:5,自引:0,他引:5
Colleen S. Conley Beth A. Haines Lori M. Hilt Gerald I. Metalsky 《Journal of abnormal child psychology》2001,29(5):445-463
This paper presents an initial assessment of the Children's Attributional Style Interview (CASI), a newly designed measure for assessing attributional style in young children (age 5 and up). The CASI was used to conduct prospective tests of the reformulated helplessness (L. Y. Abramson, M. Seligman, & J. Teasdale, 1978) and the integrated hopelessness/self-esteem (G. I. Metalsky, T. E. Joiner, Jr., T. S. Hardin, & L. Y. Abramson, 1993) theories of depression in a sample of 147 5–10-year-old children. For comparison, the same tests were also conducted with the Children's Attributional Style Questionnaire-Revised (CASQ-R; N. J. Kaslow & S. Nolen-Hoeksema, 1991), a commonly used measure for assessing attributional style in older children (age 8 and up). The CASI evidenced support of the reformulated helplessness theory and partial support of the integrated hopelessness/self-esteem theory. The CASI also demonstrated good internal consistency. Thus, our findings provide initial support for the CASI as a methodologically sound measure of attributional style for children as young as 5 years old. Although preliminary, our findings also suggest possible developmental differences in how attributional style interacts with self-esteem and negative life stress. The CASI should prove to be a useful tool in furthering the understanding of the origins and development of attributional style in childhood, as well as its contribution to the understanding of the development and prevention of depressive symptomatology in children. 相似文献
935.
936.
This paper is a critical overview of the literature on older adults' outcome after traumatic brain injury (TBI). Eighteen outcome studies were reviewed. Results indicated that older patients demonstrated an increased risk for negative outcome following TBI when compared to younger patients with similar injury severity. Poorer outcome was characterized by higher mortality rates, decreased likelihood of returning to preinjury living arrangement, and declines in cognitive and affective functioning. In the studies reviewed, discharge destination, global outcome scales, and standardized neuropsychological tests were the primary measures of outcome from elderly TBI. Conceptual and methodological difficulties including variability in the definition of and inadequate measures of recovery from elderly TBI, inadequate control groups, and poor follow-up were discussed. Recommendations for future outcome research to increase uniformity in defining recovery in order to enhance comparability between studies and to tailor cognitive rehabilitation to the special needs of the older TBI patient were provided. 相似文献
937.
Louis Lefebvre Nikoleta Juretic Nektaria Nicolakakis Sarah Timmermans 《Animal cognition》2001,4(2):91-97
The short notes of ornithology journals feature new and unusual feeding behaviours, which, when systematically collated,
could provide a quantitative estimate of behavioural flexibility in different bird groups. Previous studies suggest that taxonomic
variation in the frequency of new behaviours (innovations) is correlated with variation in relative forebrain size. Recent
work on primates shows, however, that observer bias can affect innovation frequency. We assess this possibility in birds via
three estimates in North America and Australia: the number of full-length papers in academic journals, the frequency of photographs
in birding magazines and a questionnaire on reporting bias given to ornithologists at a meeting. We also look at sampling
effects due to single journal sources by doing a split-half analysis of our North American database (The Wilson Bulletin vs. six other journals) and adding three new Australian journals to the one we had used previously. In multiple regressions
that also included species number per taxon, none of the potential biases could account for the correlation between forebrain
size and innovation frequency. Species number was the best predictor of full-length paper frequency, which was the best predictor
of photograph numbers. Ornithologists are not preferentially interested in innovative, large-brained taxa, suggesting that
the correlation between innovations and neural substrate size is not a spurious effect of the biases examined here.
Accepted after revision: 27 July 2001
Electronic Publication 相似文献
938.
Schnyer DM Dobbins IG Nicholls L Davis S Verfaellie M Schacter DL 《Memory & cognition》2007,35(6):1472-1482
Repeated classification of a visually presented stimulus rapidly leads to a form of response learning that bypasses the original evaluation in favor of a more efficient response mechanism. In two experiments, we examined the level of input and output representations that make up this form of learning. In Experiment 1, alterations in the finger mapping of the output response had no effect on the expression of response learning, demonstrating that a classification decision, not motor output, is associated with repeated items. In Experiments 2A and 2B, we tested whether response learning would transfer across different visual exemplars of a studied item. There was no evidence of transfer to different visual exemplars, even when these exemplars were judged to be highly visually similar. Taken together, these results indicate that response learning consists of the formation of an association between a specific visual representation and a classification decision. 相似文献
939.
940.
Jon Korfmacher Beth Green Mark Spellmann Kathy R. Thornburg 《Infant mental health journal》2007,28(5):459-480
As researchers have focused on better understanding those circumstances under which home visiting can lead to positive effects on parent and child outcomes, there has been growing interest in examining variation in the experiences of families within these programs, including the quality of the helping relationships between home visitors and parents. The current study examined how participating mothers perceive the helping relationship, using information collected from the Early Head Start National Research and Evaluation Project. Results suggest that although maternal report of the helping relationship is biased towards positive ratings, it remains a significant predictor of program participation, over and above general program satisfaction. Implications for measurement development and program interventions are discussed. 相似文献