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51.
The ability to wait for a reward is a necessary capacity for economic transactions. This study is an age-related investigation of children's ability to delay gratification in an exchange task requiring them to wait for a significant reward. We gave 252 children aged 2-4 a small piece of cookie, then offered them an opportunity to wait for a predetermined delay period before exchanging it for a larger one. In a first experiment, the children had to exchange the initial food item for rewards two, four or eight times larger. Results showed that children aged 3-4 years old sustained longer time lags for larger rewards than for smaller rewards. This effect was not found in 2-year-old subjects. In a second experiment, a reward 40 times larger than the initial piece was offered to determine the maximum waiting time that children could sustain. All age groups increased their performances. Older children were more successful at waiting, but some children as young as 2 years old were able to tolerate delays of up to 16 min. Older children who chose to give up waiting earlier than their known capacity demonstrated anticipation skills which had not been seen in younger children, showing that they had anticipated an increase in the time lag, and that they had considered both time and reward value when making their decision. Despite the age effect, we did not establish any limits for delaying gratification in children. This study may have educational implications for dealing with behavioral misconduct, which is known to be related to impulsivity control in young children.  相似文献   
52.
Deacon SH  Benere J  Castles A 《Cognition》2012,122(1):110-117
There is increasing evidence of a relationship between orthographic processing skill, or the ability to form, store and access word representations, and reading ability. Empirical research to date has not, however, clarified the direction of this relationship. We examined this question in a three-year longitudinal study of children from Grades 1 to 3. We included standard measures of orthographic processing skill, at both the lexical and sublexical level, and word reading accuracy, as well as controls of vocabulary, non-verbal reasoning, and phonological awareness. In all analyses, word reading predicted progress in acquiring orthographic processing skill, regardless of grade level or orthographic processing measure. In contrast, orthographic processing skill did not predict progress in word reading. Our results suggest that, between Grades 1 and 3, children acquire orthographic processing skill through their reading and that this ability, as characterized by the most common tasks used to date, does not play an independent role in supporting reading acquisition.  相似文献   
53.
We study the effect of excess kurtosis on the non-centrality parameters of the rescaled and the residual-based test statistics for covariance structure models. The analysis is based on population matrices and parameters, which eliminates the sampling variability inherent in simulation studies. We show that the non-centrality parameters, and consequently the asymptotic power, decrease as kurtosis in the data increases. Examples are provided to compare this decrease for the two test statistics, and to illustrate how substantial it is.  相似文献   
54.
The present research demonstrates that the attention bias to angry faces is modulated by how people categorize these faces. Since facial expressions contain psychologically meaningful information for social categorizations (i.e., gender, personality) but not for non-social categorizations (i.e., eye-color), angry facial expression should especially capture attention during social categorization tasks. Indeed, in three studies, participants were slower to name the gender of angry compared to happy or neutral faces, but not their color (blue or green; Study 1) or eye-color (blue or brown; Study 2). Furthermore, when different eye-colors were linked to a personality trait (introversion, extraversion) versus sensitivity to light frequencies (high, low), angry faces only slowed down categorizations when eye-color was indicative of a social characteristic (Study 3). Thus, vigilance for angry facial expressions is contingent on people's categorization goals, supporting the perspective that even basic attentional processes are moderated by social influences.  相似文献   
55.
Three studies show that social categorization is biased at the level of category allocation. In all studies, participants categorized faces. In Studies 1 and 2, participants overallocated faces with criminal features--a stereotypical negative trait--to the stigmatized Moroccan category, especially if they were prejudiced. On the contrary, the stereotype-irrelevant negative trait stupid did not lead to overallocation to the Moroccan category. In Study 3, using the stigmatized category homosexual, the previously used negative trait criminal--irrelevant to the homosexual stereotype--did not lead to overallocation, but the stereotype-relevant positive trait femininity did. These results demonstrate that normative fit is higher for faces with stereotype-relevant features regardless of valence. Moreover, individual differences in implicit prejudice predicted the extent to which stereotype-relevant traits elicited overallocation: Whereas more negatively prejudiced people showed greater overallocation of faces associated with negative stereotype-relevant traits, they showed less overallocation of faces associated with positive stereotype-relevant traits. These results support our normative fit hypothesis: In general, normative fit is better for faces with stereotypical features. Moreover, normative fit is enhanced for prejudiced individuals when these features are evaluatively congruent. Social categorization thus may be biased in itself.  相似文献   
56.
Conflicting findings exist regarding (1) whether anxiety sensitivity (AS) is a construct distinct from anxiety in children and (2) the specific nature of the role of AS in child anxiety. This study uses meta-analytic techniques to (1) determine whether youth (ages 6–18 years) have been reported to experience AS, (2) examine whether AS differentiates anxiety disordered youth from youth without diagnoses, and (3) ascertain whether AS distinguishes youth with panic disorder from those with other anxiety disorders. The weighted mean effect size analyses included 15 studies and 6,579 participants. Results suggested positive correlational relationships between AS and anxiety for children (r = 0.26) and adolescents (r = 0.36) and higher levels of AS for anxiety disordered youth than non-clinical youth (d = 0.64). Findings tentatively suggested higher levels of AS for youth with panic disorder than youth diagnosed with other anxiety disorders. Implications and future directions in the research of child AS are discussed.  相似文献   
57.
Adams’ thesis is generally agreed to be linguistically compelling for simple conditionals with factual antecedent and consequent. We propose a derivation of Adams’ thesis from the Lewis-Kratzer analysis of if-clauses as domain restrictors, applied to probability operators. We argue that Lewis’s triviality result may be seen as a result of inexpressibility of the kind familiar in generalized quantifier theory. Some implications of the Lewis-Kratzer analysis are presented concerning the assignment of probabilities to compounds of conditionals.  相似文献   
58.
Premarital sex remains stigmatized even as the unmarried period of life is lengthening in India. This paper examines how young unmarried men in rural central India conceptualize and understand their sexual health and vulnerability. The data is qualitative, derived from four focus group discussions (N = 38 persons) of young unmarried males that were carried out in conjunction with a larger study on male involvement in reproductive health in the central Indian state of Madhya Pradesh in 2005. Young, unmarried rural men experience a wide range of functional situations which are culturally defined as health problems, such as “weakness,” thought to be caused by masturbation, nocturnal ejaculations, and the loss of semen. Despite constraints on communication on sexuality with married men, young unmarried men largely share with them the culturally hegemonic notion of semen loss as a health hazard. All four discussions pointed to the negative image of psycho-physiological changes related to maturation and further, to the belief that the reproductive functions of men can render them vulnerable and even harm them. Sexual anxiety in young men may in part reflect young men’s socially dependent and insecure life situation and social suffering. Young, unmarried rural men see marriage as the only release from sexual health problems although temporary relief is sought from private health care providers. In the future, men’s unmarried life stage is bound to lengthen in rural India, and consequently sexual health prior to the commencement of active intercourse should receive more attention in public health services and sex education.  相似文献   
59.
Safety in numbers is thought to be the principal advantage of living in groups for many species. The group can only provide protection against predators, however, when group cohesion is maintained. Vocalisations are used to monitor inter-individual distances, especially under conditions of poor visibility, but should be avoided in the presence of predators. Mentally tracking the movements of silent and invisible group members would allow animals foraging in dense vegetation to stay close to their group members while reducing the use of vocal contact. We tested the socio-spatial cognitive abilities of wild vervet monkeys (Chlorocebus pygerythrus) by comparing their reactions to plausible and implausible displacements of group members simulated by sound playbacks. Our methods are comparable to those used in studies of ‘object permanence’ and ‘invisible displacements’ of inanimate objects. Our results show that vervets can track the whereabouts of invisibly and silently moving group members, at least over short periods of time.  相似文献   
60.
Relational processing involves learning about the relationship between or among stimuli, transcending the individual stimuli, so that abstract knowledge generalizable to novel situations is acquired. Relational processing has been studied in animals as well as in humans, but little attention has been paid to the contribution of specific items to relational thinking or to the factors that may affect that contribution. This study assessed the intertwined effects of item and relational processing in nonhuman primates. Using a procedure that entailed both expanding and contracting sets of pictorial items, we trained 13 baboons on a two-alternative forced-choice task, in which they had to distinguish horizontal from vertical relational patterns. In Experiment 1, monkeys engaged in item-based processing with a small training set size, and they progressively engaged in relation-based processing as training set size was increased. However, in Experiment 2, overtraining with a small stimulus set promoted the processing of item-based information. These findings underscore similarities in how humans and nonhuman primates process higher-order stimulus relations.  相似文献   
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