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81.
In Jamaica the public discourse on homosexuality is voluminous, however little or no empirical research or suitably detached policy-oriented discussion is in evidence. This multidisciplinary qualitative paper uses the content analysis of publicly available information to explore the posture of key public-policy actors on homosexuals and homosexuality. The observable implications of the findings for society and the rights of homosexuals are articulated. The paper concludes that this discourse evinces a settled heteronormative value system, reflecting a consensus on either side of the political divide and applauded by popular culture and popular opinion. At a time when most of the western world is embracing sexual diversity, these conclusions carry profound implications for legal reform, employment relations, social justice and public policy in Jamaica.  相似文献   
82.
The purpose of this study was to assess effects of an audience on learning a novel motor skill. Subjects (N=64) were randomly assigned to one of four experimental conditions and administered 15 30-sec. trials with 30 sec. intertrial periods on a pursuit rotor task on two different days. Comparison of Time-on Target performance between conditions indicated that the No Audience condition had significantly higher performance than the Audience condition in Session 1. Comparison of Absolute Retention and Final Retention scores among the four experimental conditions in Session 2 after 48 hr. yielded no significant differences attributable to the presence of an audience, thus supporting the hypothesis that an audience would have no effect on learning.  相似文献   
83.
Newborn screening (NBS) protocols for cystic fibrosis (CF) are the first regional population-based programs to incorporate DNA analysis into their procedures. Research about these programs can inform policy and practice regarding how best to counsel families with abnormal NBS results. The grounded theory method guided interviews with 33 families whose infants had abnormal CF NBS results. A dimensional analysis of these interviews provided a theoretical framework describing parents’ preferences regarding counseling during their infant's sweat test appointment. This framework describes the contexts and characteristics of the two main dimensions of parents’ preferences: factual information and emotional support. Factual information included learning about the probability of a CF diagnosis, CF disease facts, sweat test procedure, and CF genetics. Social support consisted of offering parents a choice about the timing and amount of CF information, showing empathy for their distress, instilling hope, personalizing counseling, and providing hospitality. This framework also explains the consequences of counseling that matched versus mismatched parental preferences in these domains. Counseling that matched parents preferences reduced parents’ distress while mismatched counseling tended to increase parents’ worry about their infant.  相似文献   
84.
Dopamine is critical for directing goal-oriented behavior. We investigated dopamine D2 receptor involvement in reversal learning and reinforcement efficacy in mice lacking functional dopamine D2 receptors and their heterozygous and wild-type littermates. Mice discriminated between two odors to receive a food reinforcer: One odor signaled a reinforcer (S+); the other odor signaled no reinforcer (S). After mice learned the S+/S relationship, we inverted the reinforcement contingencies. The necessary number of trials to relearn the new reinforcement contingencies served as our index of reversal learning. Mice lacking functional dopamine D2 receptors repeatedly failed to inhibit previously reinforced responses during reversal trials. In a separate experiment, mice responded for reinforcers on a progressive ratio schedule of reinforcement. Mice lacking functional dopamine D2 receptors earned significantly fewer reinforcers than did heterozygous mice. Our results suggest that dopamine D2 receptors regulate reversal learning and influence the reinforcing efficacy of natural rewards.  相似文献   
85.
In contrast with major theories of attitudes and behavior, the authors propose that individuals are not equally motivated to pursue their self-interests. The authors show that differences in other orientation affect the extent to which actions and attitudes reflect self-interested calculation (instrumental rationality) and the extent to which beliefs represent their external environment (epistemic rationality). These differences have consequences for processes underlying a wide range of attitudes and behavior typically assumed to be rationally self-interested. Thus, the authors' model exposes a common explanation for diverse organizational phenomena. It also clarifies inconsistencies surrounding the validity of certain attitudinal and motivational models, the relationship between job attitudes and actions, cross-cultural differences in attitudes and behavior, escalation of commitment, and the relationship between chief executive officer characteristics and organizational performance.  相似文献   
86.
Experiments are designed to assess whether free-flying honey bees have an aversion to an ethanol solution when given a choice between targets containing an ethanol solution in sucrose or sucrose only. Animals given a choice between a 1% ethanol solution and sucrose only show no aversion to the ethanol solution either in acquisition or extinction. Honey bees given a choice between a 5% ethanol solution and sucrose only show no differences in the initial choice of targets but some ees do switch over to the sucrose-only target. Performance during extinction indicates that bees landed on the previously reinforced sucrose-only target more than the target previously containing the 5% ethanol solution. An experiment in which bees were given a single 5%, ethanol target showed that of 20 bees, 11 returned for the entire 12 trials of the experiment. All bees returned at least 6 times to the 5% ethanol target. Additional experiments were run on harnessed foragers in a palatability study of alcoholic beverages consumed by humans. The results of the palatability experiment indicate that in general, bees prefer more sweet drinks with less alcohol.  相似文献   
87.
88.
Knowledge-based programs (KBPs) are a powerful notion for expressing action policies in which branching conditions refer to implicit knowledge and call for a deliberation task at execution time. However, branching conditions in KBPs cannot refer to possibly erroneous beliefs or to graded belief, such as “if my belief that φ holds is high then do some action α else perform some sensing action β”. The purpose of this paper is to build a framework where such programs can be expressed. In this paper we focus on the execution of such a program (a companion paper investigates issues relevant to the off-line evaluation and construction of such programs). We define a simple graded version of doxastic logic KD45 as the basis for the definition of belief-based programs. Then we study the way the agent’s belief state is maintained when executing such programs, which calls for revising belief states by observations (possibly unreliable or imprecise) and progressing belief states by physical actions (which may have normal as well as exceptional effects). * A premliminary and shorter version of this paper in the Proceedings of the 16th European Conference on Artificial Intelligence (ECAI-04), pp. 368–372 (Laverny and Lang 2004).  相似文献   
89.
In the first half of this review, the authors critically evaluate existing research on the association between stressors and symptoms of psychopathology in children and adolescents. This analysis reveals (a) problems with conceptualizations of stress, (b) variability in measurement of stressors, and (c) lack of theory-driven research. To address these problems, the authors propose a general conceptual model of the relation between stressors and child and adolescent psychopathology. The authors examine basic tenets of this general model in the second half of this article by testing a specific model in which negative parenting mediates the relation between economic stressors and psychological symptoms in young people. Results generally provide support for the specific model as well as for the broader model.  相似文献   
90.
Researchers commonly use 2 models to explain contrast effects (CEs): the standard-of-comparison model and the set-reset model. The 2 models focus on the role of categorization to predict when a CE (instead of an assimilation effect) will happen, while minimizing the role of knowledge accessibility and relevance in determining whether any effect will occur. A 3rd model, the selective-accessibility model (F. Strack & T. Mussweiler, 1997), focuses on knowledge accessibility and relevance, but it is a model of assimilation effects in the anchoring bias. In the present study of CEs, the authors tested 3 predictions implied by the selective-accessibility model. The authors found a CE only when anchor- and target-rating dimensions matched and only in the 1st of multiple targets rated. The CE required a minimum amount of attention to the anchor. These results support the account that selective knowledge accessibility and relevance play an important role in CEs.  相似文献   
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