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141.
Suicide deaths are often viewed as sudden and unexpected. Research examining bereavement responses to suicide are generally set within this conceptual framework. Twenty-two parents were interviewed about their bereavement experience following the suicide death of a young adult son or daughter. Data analyzed using narrative methods revealed the concept of preparedness. Three distinct preparedness narratives were identified, termed turbulent-relief, tragedy, and reflective plots. The data presented here highlights the way in which these different situations influence the resultant grief. Understanding preparedness for suicide assists in explaining the variety of grief responses in parents bereaved in this manner. 相似文献
142.
The neural consequences of semantic richness: when more comes to mind, less activation is observed 总被引:1,自引:0,他引:1
Some concepts have richer semantic representations than others. That is, when considering the meaning of concepts, subjects generate more information (more features, more associates) for some concepts than for others. This variability in semantic richness influences responses in speeded tasks that involve semantic processing, such as lexical decision and semantic categorization tasks. It has been suggested that concepts with richer semantic representations build stronger attractors in semantic space, allowing faster settling of activation patterns and thus faster responding. Using event-related functional magnetic resonance imaging, we examined the neural activation associated with semantic richness by contrasting activation for words with high and low numbers of associates in a semantic categorization task. Results were consistent with faster semantic settling for words with richer representations: Words with a low number of semantic associates produced more activation than words with a high number of semantic associates in a number of regions, including left inferior frontal and inferior temporal gyri. 相似文献
143.
Enriching the environment of alphaCaMKIIT286A mutant mice reveals that LTD occurs in memory processing but must be subsequently reversed by LTP
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Parsley SL Pilgram SM Soto F Giese KP Edwards FA 《Learning & memory (Cold Spring Harbor, N.Y.)》2007,14(1-2):75-83
alphaCaMKII(T286A) mutant mice lack long-term potentiation (LTP) in the hippocampal CA1 region and are impaired in spatial learning. In situ hybridization confirms that the mutant mice show the same developmental expression of alphaCaMKII as their wild-type littermates. A simple hypothesis would suggest that if LTP is a substrate for learning, then enriching the environment should cause learning-dependent changes in wild-type mice that have LTP. Such changes would not be seen in LTP-deficient alphaCaMKII(T286A) mutants. Excitatory synaptic currents in CA1 neurons, recorded with patch clamp in brain slices, revealed that enrichment induces an increase in glutamate release probability and a decreased miniature current amplitude. Confocal microscopy also showed dendritic spine density to be reduced. However, contrary to the hypothesis above, these enrichment-induced changes occur only in the mutant mice and are not detectable in wild-type littermates. We suggest that enrichment induces alphaCaMKII-independent changes in both wild-type and mutant mice. Such changes may be subsequently reversed in wild-type animals via alphaCaMKII-dependent mechanisms, such as LTP. Reversal of plasticity has long been hypothesized to be essential for the hippocampus to maintain its role in memory processing. The inability to reverse plasticity in alphaCaMKII(T286A) mutant mice would then result in impairment of spatial learning. 相似文献
144.
Patrick D. Converse Mitchell H. Peterson Richard L. Griffith 《International Journal of Selection & Assessment》2009,17(1):47-60
The potential for faking on noncognitive measures in high stakes testing situations remains a concern for many selection researchers and practitioners. However, the majority of previous research examining the practical effects of faking on noncognitive assessments has focused on these measures in isolation, rather than the more common situation in which they are used in combination with other predictors. The present simulation examined the effects of faking on a conscientiousness measure on criterion‐related validity, mean performance of those selected, and selection decision consistency when hiring decisions were based on this measure alone vs in combination with two other predictors across a range of likely selection scenarios. Overall, results indicated that including additional predictors substantially reduced – but did not eliminate – the negative effects of faking. Faking effects varied across outcomes and selection scenarios, with effects ranging from trivial to noteworthy even for multiple‐predictor selection. Implications for future research and practice are discussed. 相似文献
145.
Courtship learning in Drosophila melanogaster: Diverse plasticity of a reproductive behavior
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Mechanisms for identifying appropriate mating partners are critical for species propagation. In many species, the male uses multiple sensory modalities to search for females and to subsequently determine if they are fit and receptive. Males can also use the information they acquire in this process to change their courtship behavior and reduce courtship of classes of targets that are inappropriate or unreceptive. In Drosophila, courtship plasticity, in the form of both nonassociative and associative learning, has been documented—the type of learning depending on the nature of the trainer. The conditions in which the male is presented with the training target can profoundly alter the cues that he finds salient and the longevity of the memory that he forms. With the exception of habituation and sensitization, these types of plasticity have an operant component in that the male must be courting to respond to the behavior-altering cues. Courtship plasticity is therefore a complex and rich range of behaviors rather than a single entity. Our understanding of these plastic behaviors has been enhanced by recent advances in our understanding of the circuitry underlying courtship itself and the identification of chemical cues that drive and modify the behavior. Courtship learning is providing a window into how animals can use a variety of sensory inputs to modulate a decision making process at many levels.When confronted with a potential mate, Drosophila melanogaster males perform a stereotyped courtship ritual. This behavior serves at least two obvious functions for the male. The first is to prime conspecific females for copulation. During courtship, the female is assessing the male''s suitability, and if the song he sings (Burnet et al. 1971; von Schilcher 1976a) and pheromones he emits (Grillet et al. 2006; Kurtovic et al. 2007) are correct for her species and of sufficient quality, her willingness to copulate is increased. She will slow her locomotion, present her abdomen to the male, and then spread her wings and genital plates to allow him to mount (Lasbleiz et al. 2006). A second function of courtship is that it allows a male to accumulate information about the target courtship object to assess its suitability and receptiveness. The male uses auditory, mechanosensory, visual, and chemosensory signals from the target to make this assessment (for review, see Villella and Hall 2008; Ejima and Griffith 2009).Since D. melanogaster males will avidly initiate courtship of a wide variety of inappropriate and/or unreceptive targets, including immature males, sexually immature virgin females, mated females, and heterospecific females, the information obtained during courtship is critical to deciding whether to increase the intensity of his effort or terminate pursuit of the target. In the last several years, courtship has become a favored model for those researchers interested in how the nervous system specifies “innate” behaviors. While it is true that a male does not have to be instructed to produce adequate courtship (Hall 1994; Clyne and Miesenbock 2008), this apparently stereotyped behavior is far from static: It can be modified in a dizzying number of ways by experience. In this paper, we will discuss how information gathered during courtship can allow males to learn about specific types of courtship objects and broadly modify future behavioral responses to a particular class of target. 相似文献
146.
Form A of the Dysfunctional Attitude Scale (DAS-A), a self-report measure of depressive beliefs, is widely used to test Beck's cognitive model of depression. The present study is the first to evaluate the DAS-A factor structure in an adolescent population of 542 high school juniors and the first to examine a hierarchical model. Findings support the existence of a hierarchical structure consisting of two conceptually meaningful group factors (Dysfunctional Attitudes About Achievement and Dysfunctional Attitudes About Needing Approval), a method factor consisting of reverse-worded items, and a general factor, which accounts for 65% of the variance in total scores. The general factor is related to sociotropy, autonomy, and neuroticism, whereas the Dysfunctional Attitudes About Achievement and Dysfunctional Attitudes About Needing Approval factors demonstrate convergent and discriminant validity with respect to autonomy and sociotropy. The structure displays partial metric invariance in female and male students as well as in Caucasian and Non-Caucasian students. 相似文献
147.
148.
Edwards MC Gardner ES Chelonis JJ Schulz EG Flake RA Diaz PF 《Journal of abnormal child psychology》2007,35(3):393-404
This study evaluated the validity and classification utility of the Conners' Continuous Performance Test (CCPT) in the assessment of inattentive and hyperactive-impulsive behaviors in children. Significant, positive correlations between the CCPT parameters and behavioral ratings of ADHD behaviors were hypothesized. In addition, it was hypothesized that the CCPT parameters would perform better than a random test (chance) and show fair to moderate utility of classification across the different indices. Participants were 104 children between 6 and 12 years of age who were referred for evaluation of attention problems. The first hypothesis was not supported. There were no significant, positive correlations between the CCPT parameters and parent and teacher ratings of inattentive and hyperactive-impulsive behaviors. The second hypothesis was only partially supported. The CCPT Overall Index and the Omission Errors (84th percentile cutoff) performed better than a random test; however, the utility of the CCPT Overall Index only ranged from poor to slight. Receiver operating characteristic analyses showed the accuracy of the CCPT to be low. The implications and limitations of this study and future research directions are discussed. 相似文献
149.
Examined the free-field interaction of 32 mother-child dyads who volunteered to participate in a 1-hr home observation. Observers coded mother instructions, child compliance, and child prosocial approaches plus mothers' social attention as potential reinforcers for the children's compliance and social approaches. Herrnstein's matching law was used to analyze covariations between mothers' attention and the children's 2 responses. This analysis was followed by correlational and sequential probability analyses to determine linkages between these 2 child responses and the children's willingness to obey their mothers' instructions. Results showed consistent matching between mothers' social attention and the children's production of prosocial approaches and acts of compliance. An index of the proportions of these 2 responses also covaried with the children's compliance probabilities, and the prosocial approach component was the direct covariate. These findings are discussed within an interactional synchrony framework in which children's willingness to obey their mothers is influenced by opportunities for the dyad to engage each other in specific forms of social interaction. 相似文献
150.