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971.
To estimate the prevalence of being well-adjusted in adolescence, boys and girls with (n = 96) and without (n = 126) attention-deficit/hyperactivity disorder (ADHD) were assessed seven times in eight years starting when they were 4–6 years of age. Symptoms of ADHD, ODD/CD, and depression/anxiety in addition to social skills and social preference were gathered using multiple methods and informants. Being well-adjusted was defined by surpassing thresholds in at least four of the five domains. At the 7- and 8-year follow-up, when youth were 11–14 years old, probands were significantly less likely to be well-adjusted relative to age- and ethnicity-matched control children. Only a minority of children with ADHD was well-adjusted in adolescence when emotional, behavioral, and social domains were considered simultaneously. Even when their ADHD symptoms improved over time, most probands exhibited significant impairment 7–8 years after their initial assessment.  相似文献   
972.
Drawing on transactional theories of child development, we assessed bidirectional links between trajectories of adolescent substance use and parenting processes from early through mid adolescence. Hierarchical generalized models estimated trajectories for 3,317 adolescents from the National Longitudinal Survey of Youth 1997, exploring both between- and within-individual effects. Between individuals, adolescents reporting more regular family activities and greater father and mother knowledge of friends and teachers experienced lower levels of substance use through mid adolescence. Similarly, adolescents with more frequent substance use reported lower family activities, father knowledge, and mother knowledge, though these differences dissipated over time. More conservative within-individual differences indicated a prospective protective effect of family activities, with increases in adolescent participation in family activities predicting later declines in substance use. Results support the central importance of engagement in regular family activities, and suggest the need for further exploration of transactional processes between parents and children in the development of risk behaviors.  相似文献   
973.
This study examined potential differences between the inattentive and combined ADHD subtypes using laboratory tasks assessing behavioral inhibitory processes. Seventy-five children completed two tasks of behavioral inhibition believed to isolate different processes: the cued reaction time task (CRT), a basic inhibition task, and the go/no-go task (GNG), a complex inhibition task that incorporates motivational contingencies. Three groups of participants were identified, including ADHD/Inattentive (n = 17), ADHD/Combined (n = 37), and comparison (n = 21). Results indicated that rather than showing behavioral inhibition deficits, the ADHD/I children appeared overly inhibited, as evidenced by slower reaction times across the two tasks and significantly higher errors of omission in the GNG task. Additionally, the ADHD/I children did not demonstrate cue dependency effects on the CRT task, suggesting that they were failing to incorporate relevant information before making a response. The sluggish and inhibited performance of the ADHD/I group challenges the idea that it is a subtype of ADHD.  相似文献   
974.
Overconcern with weight and shape and body dissatisfaction have both emerged as significant predictors of disordered eating. However, it is unclear how these constructs relate to each other, and if each has different antecedents and consequences. This study aimed to identify prospective predictors of each construct and to determine their relative importance in predicting dietary restraint and binge eating. Eight- to 13-year-old boys and girls (N = 259) were assessed at baseline and one-year follow-up, using a range of measures that included the Child Eating Disorder Examination. Psychosocial variables predicted overconcern with weight and shape whilst objective weight predicted body dissatisfaction. Body dissatisfaction and weight and shape concern predicted restraint, and weight and shape concern and restraint predicted binge eating. Findings provide support for the theoretical differences between body dissatisfaction and overconcern with weight and shape, and highlight the importance of focusing on specific body image variables.  相似文献   
975.
The current study was conducted to determine if electronic gaming among males is related to body image, formation of body ideals, and appraisals of female attractiveness. A sample of 219 college-aged men (age 18-32) completed a variety of measures that assessed their game play habits, their perceptions of their own attractiveness, and perceptions of women's attractiveness. Results indicated that participants' ratings of women's attractiveness varied across the genres of game most frequently played but was not related to age of commencement or frequency of electronic game play. Additionally, frequency of play and age of commencement of game play were not related to self-perceptions of physical attractiveness, the association of positive attributes with muscularity, or the drive to become more muscular. Men's appearance satisfaction and valuation of muscularity was related to the extent to which they compare their own appearance to that of the characters featured in their electronic games. The results indicate that, unlike other forms of media, electronic gaming may have a weaker relationship to decreased appearance satisfaction or the formation of unrealistic standards of attractiveness.  相似文献   
976.
Prior research has examined the relations between various facets of emotion and psychopathology, with a great deal of recent work highlighting the importance of emotion regulation strategies. Much less attention has been given to the examination of emotion reactivity. This study reports on the development and evaluation of the Emotion Reactivity Scale (ERS), a 21-item self-report measure of emotion sensitivity, intensity, and persistence, among a sample of 87 adolescents and young adults. Factor analysis revealed a single factor of emotion reactivity best characterized the data. The ERS showed strong internal consistency (alpha=.94), convergent and divergent validity via relations with behavioral inhibition/activation and temperament, and criterion-related validity as measured by associations with specific types of psychopathology and self-injurious thoughts and behaviors (SITB). Moreover, emotion reactivity statistically mediated the relation between psychopathology and SITB. These findings provide preliminary support for the ERS and suggest that increased emotion reactivity may help explain the association between psychopathology and SITB.  相似文献   
977.
Past research has demonstrated consistent sex differences with men typically outperforming women on tests of spatial ability. However, less is known about intra‐sex effects. In the present study, two groups of female students (physical education and non‐physical education secondary students) and two corresponding groups of male students explored a large‐scale virtual shopping centre. In a battery of tasks, spatial knowledge of the shopping centre as well as mental rotation ability were tested. Additional variables considered were circulating testosterone levels, the ratio of 2D:4D digit length, and computer experience. The results revealed both sex and intra‐sex differences in spatial ability. Variables related to virtual navigation and computer ability and experience were found to be the most powerful predictors of group membership. Our results suggest that in female and male secondary students, participation in physical education and spatial skill are related.  相似文献   
978.
Gilmore CK  Spelke ES 《Cognition》2008,107(3):932-945
In learning mathematics, children must master fundamental logical relationships, including the inverse relationship between addition and subtraction. At the start of elementary school, children lack generalized understanding of this relationship in the context of exact arithmetic problems: they fail to judge, for example, that 12 + 9 − 9 yields 12. Here, we investigate whether preschool children’s approximate number knowledge nevertheless supports understanding of this relationship. Five-year-old children were more accurate on approximate large-number arithmetic problems that involved an inverse transformation than those that did not, when problems were presented in either non-symbolic or symbolic form. In contrast they showed no advantage for problems involving an inverse transformation when exact arithmetic was involved. Prior to formal schooling, children therefore show generalized understanding of at least one logical principle of arithmetic. The teaching of mathematics may be enhanced by building on this understanding.  相似文献   
979.
Do children draw upon abstract representations of number when they perform approximate arithmetic operations? In this study, kindergarten children viewed animations suggesting addition of a sequence of sounds to an array of dots, and they compared the sum to a second dot array that differed from the sum by 1 of 3 ratios. Children performed this task successfully with all the signatures of adults' nonsymbolic number representations: accuracy modulated by the ratio of the sum and the comparison quantity, equal performance for within- and cross-modality tasks and for addition and comparison tasks, and performance superior to that of a matched subtraction task. The findings provide clear evidence for nonsymbolic numerical operations on abstract numerical quantities in children who have not yet been taught formal arithmetic.  相似文献   
980.
Controversy surrounding dissociative identity disorder (DID) has focused on conflicting findings regarding the validity and nature of interidentity amnesia, illustrating the need for objective methods of examining amnesia that can discriminate between explicit and implicit memory transfer. In the present study, the authors used a cross-modal manipulation designed to mitigate implicit memory effects. Explicit memory transfer between identities was examined in 7 DID participants and 34 matched control participants. After words were presented to one identity auditorily, the authors tested another identity for memory of those words in the visual modality using an exclusion paradigm. Despite self-reported interidentity amnesia, memory for experimental stimuli transferred between identities. DID patients showed no superior ability to compartmentalize information, as would be expected with interidentity amnesia. The cross-modal nature of the test makes it unlikely that memory transfer was implicit. These findings demonstrate that subjective reports of interidentity amnesia are not necessarily corroborated by objective tests of explicit memory transfer.  相似文献   
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