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911.
912.
The aim of the present study was to assess the effects of daily stress perception on cognitive performance and morning basal salivary cortisol and alpha-amylase levels in healthy children aged 9-12. Participants were classified by whether they had low daily perceived stress (LPS, n = 27) or a high daily perceived stress (HPS, n = 26) using the Children Daily Stress Inventory (CDSI). Salivary cortisol and alpha-amylase were measured at awakening and 30 minutes later. Cognitive performance was assessed using the Cognitive Drug Research assessment system. The HPS group exhibited significantly poorer scores on speed of memory (p < .05) and continuity of attention (p < .05) relative to the LPS group. The HPS group also showed significantly lower morning cortisol levels at awakening and at +30 minutes measures in comparison with the LPS group (p < .05), and mean morning cortisol levels were negatively correlated with speed of memory (p < .05) in the 53 participants. No significant differences were observed between both groups in alpha-amylase levels. These findings suggest that daily perceived stress in children may impoverish cognitive performance via its modulating effects on the HPA axis activity.  相似文献   
913.
This study explored whether Smith and Lazarus' (1990, 1993) cognitive theory of emotion could predict emotional responses to an emotionally ambiguous real-life situation. Questionnaire data were collected from 145 women upon referral for cancer genetic risk assessment. These indicated a mixed emotional reaction of both positive and negative emotions to the assessment. Hierarchical regression analyses revealed that the hypothesised models explained between 20% and 33% of the variance of anxiety, hope and gratitude scores, but only 10% of the variance for challenge scores. For the previously unmodelled emotion of relief, 31% of the variance was explained by appraisals and core relational themes. The findings help explain why emotional responses to cancer genetic risk assessment vary and suggest that improving the accuracy of individuals' beliefs and expectations about the assessment process may help subsequent adaptation to risk information.  相似文献   
914.
The McGurk effect paradigm was used to examine the developmental onset of inter-language differences between Japanese and English in auditory-visual speech perception. Participants were asked to identify syllables in audiovisual (with congruent or discrepant auditory and visual components), audio-only, and video-only presentations at various signal-to-noise levels. In Experiment 1 with two groups of adults, native speakers of Japanese and native speakers of English, the results on both percent visually influenced responses and reaction time supported previous reports of a weaker visual influence for Japanese participants. In Experiment 2, an additional three age groups (6, 8, and 11 years) in each language group were tested. The results showed that the degree of visual influence was low and equivalent for Japanese and English language 6-year-olds, and increased over age for English language participants, especially between 6 and 8 years, but remained the same for Japanese participants. This may be related to the fact that English language adults and older children processed visual speech information relatively faster than auditory information whereas no such inter-modal differences were found in the Japanese participants' reaction times.  相似文献   
915.
A critical challenge for visual perception is to represent objects as the same persisting individuals over time and motion. Across several areas of cognitive science, researchers have identified cohesion as among the most important theoretical principles of object persistence: An object must maintain a single bounded contour over time. Drawing inspiration from recent work in adult visual cognition, the present study tested the power of cohesion as a constraint as it operates early in development. In particular, we tested whether the most minimal cohesion violation - a single object splitting into two - would destroy infants' ability to represent a quantity of objects over occlusion. In a forced-choice crawling paradigm, 10- and 12-month-old infants witnessed crackers being sequentially placed into containers, and typically crawled toward the container with the greater cracker quantity. When one of the crackers was visibly split in half, however, infants failed to represent the relative quantities, despite controls for the overall quantities and the motions involved. This result helps to characterize the fidelity and specificity of cohesion as a fundamental principle of object persistence, suggesting that even the simplest possible cohesion violation can dramatically impair infants' object representations and influence their overt behavior.  相似文献   
916.
Whither geometry? Troubles of the geometric module   总被引:6,自引:0,他引:6  
In rectangular arenas, rats often confuse diagonally opposite corners, even when distinctive cues differentiate them. This led to the postulation that rats rely preferentially on the geometry of space, encoded in a dedicated geometric module. Recent research casts doubt on this idea. Distinctive featural cues such as entire walls of a distinct color can hinder or aid the learning of geometry. In one situation in which using geometry would help greatly, rats had trouble learning the task. An associative model has been developed to capture these different learning processes, and view-based matching has been proposed as an alternative to the explicit coding of geometric cues. Considerations about how cues interact in learning are crucial in a recent theory of human spatial cognition.  相似文献   
917.
Impairments in visual attention and visual information processing have been identified as part of the neuropsychological features of Alzheimer's disease (AD), even in its earliest stages. There is increasing recognition that these deficits may be selective rather than global, with some attentional subtypes being more vulnerable than others. The few studies that have investigated attentional deficits in mild cognitive impairment (MCI), a putatively prodromal phase of AD, have not satisfactorily addressed the possible selectivity in attentional deficits in MCI. This study examined potential dissociations in visual attention deficits in MCI using a measure that assesses simple, divided, and selective attention. The results indicated a hierarchy of attentional impairments, with divided attention being the most affected and simple attention the least. Among participants with MCI, 53% showed evidence of impairment in divided attention compared to 19% of controls (OR = 4.81, p < .001). Poorer visual attention was also associated with poorer overall cognitive status. The implications of these findings for early identification of MCI, prevention of functional decline in MCI, and delay/reversal of cognitive degradation in MCI are discussed.  相似文献   
918.
女性拥有与生俱来的内心敏感和异常脆弱的心绪。生活在北欧寒冷国度下的女性,她们的镜头关注着自身,一部部视觉日记的诞生,真实直面地反映着当代女性温暖纯净的心灵体验。  相似文献   
919.
The authors examined the associations that underlie the orientations of bilingual Latino college students toward family and school. Participants completed, in English or Spanish, 3 implicit association tests assessing their attitude toward family vs. school, identifications with these concepts, and self-esteem. Results revealed a more positive attitude toward, and stronger identification with, family than school. Identification with family was stronger among participants who completed the study in English, suggesting self-definition in terms of distinctions from the context. Last, the more participants valued family over school and identified with family rather than school, the higher was their self-esteem. These findings shed light on the subtle, yet crucial, mechanisms by which cultural knowledge is incorporated in the self-concept of bilingual Latino college students.  相似文献   
920.
The authors conducted 2 studies to examine the stigmatization of the female and male body using photographic stimuli of real people. In the first study, 75 female and 55 male undergraduates rated a series of 50 photographs of women ranging in body mass index (BMI) on 3 items: gets teased, lonely, and lazy. Both male and female observers rated bodies on either side of BMI 19-20 kg/m2 higher for the gets teased and lonely items. For the lazy item, there was a clear pattern of greater stigmatization with increasing BMI. In the second study, 40 male and 40 female observers rated a series of photographs of the male body that varied in BMI and waist-to-chest ratio on the same items. Results showed that men and women judged overweight and more tubular men to be lazier, lonelier, and teased. These findings suggest that body size is an important characteristic to consider when examining body stigmatization among men and women. These results also show support for the beautiful-is-good bias.  相似文献   
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