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131.
132.
Seventy children were observed during structured play with their primary professional caregivers and three peers in the child care center and with their primary caregiving parents at home at 15 and 23 months of age. The same structured play tasks were used in the two settings and the quality of the children's interactions with caregivers and parents was rated using the same 7-point scales. As expected, the quality of caregiver–child interactions significantly increased between 15 and 23 months. At 15 months, the quality of caregiver–child interactions was significantly lower than the quality of parent–child interactions, particularly with regard to caregiver supportive presence and respect for the child's autonomy. At 23 months, however, the quality of caregiver–child interactions was no longer lower and in some respects even higher than the quality of parent–child interactions. At both ages, the children expressed more negativity towards their parents than towards their professional caregivers.  相似文献   
133.
A positive effect of breastfeeding on the mother–infant relationship is often assumed in the scientific literature, but this has not been systematically reviewed. This review aims to clarify the role of breastfeeding in the mother–infant relationship, which is conceptualized as the maternal bond toward the infant and infant attachment toward the mother. Our findings indicate that theoretical mechanisms through which breastfeeding may enhance the maternal bond or infant attachment (i.e., endocrine and sensory factors involved in breastfeeding) can be found in both humans and animal models. However, the few empirical studies investigating this association have not found convincing support for a relation between breastfeeding and the quality of the mother–infant relationship. We therefore conclude that assumptions on a positive role of breastfeeding on the mother–infant relationship are not supported by empirical evidence, and recommendation of breastfeeding should solely be based on its well-documented positive effects on infant and maternal health.  相似文献   
134.
Tests of accuracy in interpersonal perception take many forms. Often, such tests use designs and scoring methods that produce overall accuracy levels that cannot be directly compared across tests. Therefore, progress in understanding accuracy levels has been hampered. The present article employed several techniques for achieving score equivalency. Mean accuracy was converted to a common metric, pi [Rosenthal, R., & Rubin, D. B. (1989). Effect size estimation for one-sample multiple-choice-type data: Design, analysis, and meta-analysis. Psychological Bulletin, 106, 332–337] in a database of 109 published results representing tests that varied in terms of scoring method (proportion accuracy versus correlation), content (e.g., personality versus affect), number of response options, item preselection, cue channel (e.g., face versus voice), stimulus duration, and dynamism. Overall, accuracy was midway between guessing level and a perfect score, with accuracy being higher for tests based on preselected than unselected stimuli. When item preselection was held constant, accuracy was equivalent for judging affect and judging personality. However, comparisons must be made with caution due to methodological variations between studies and gaps in the literature.  相似文献   
135.
Regulatory focus theory distinguishes between two independent structures of strategic inclination, promotion versus prevention. However, the theory implies two potentially independent definitions of these inclinations, the self-guide versus the reference-point definitions. Two scales (the Regulatory Focus Questionnaire, Higgins al., 2001, and the General Regulatory Focus Measure, Lockwood, Jordan, & Kunda, 2002) have been widely used to measure dispositional regulatory focus. We suggest that these two scales align respectively with the two definitions, and find that the two scales are largely uncorrelated. Both conceptual and methodological implications are discussed.  相似文献   
136.
Two studies investigated the role of locomotor experience on visual proprioception in 8-month-old infants. Visual proprioception refers to the sense of self-motion induced in a static person by patterns of optic flow. A moving room apparatus permitted displacement of an entire enclosure (except for the floor) or the side walls and ceiling. In Study 1, creeping infants and prelocomotor/walker infants showed significantly greater postural compensation and emotional responses to side wall movement than did same-age prelocomotor infants. Study 2 used true random assignment of prelocomotor infants to locomotor-training (via a powered-mobility device) and no-training conditions. Experimental infants showed powerful effects of locomotor training. These results imply that locomotor experience is playing a causal role in the ontogeny of visual proprioception.  相似文献   
137.
Developmental theories of prosocial reasoning and behavior posit a transition from concrete (e.g., give a toy to receive one) to abstract (e.g., spend time to make someone happy) forms and have been supported with research on middle-socioeconomic status (SES), White samples. The methodology that researchers have used to date has restricted the responses that children can offer. In the present study, 122 Grade 2 and Grade 4 children from low-SES families described different types of motives and behavior and whether a conflict existed between self- and other-serving behaviors. The authors found developmental differences for both abstract and tangible motives that focused on the benefactor of prosocial behavior. Grade 2 girls and Grade 4 boys were the most likely to spontaneously describe a conflict between self- and other-serving behaviors.  相似文献   
138.
Activation of β-adrenergic receptors (β-ARs) enhances hippocampal memory consolidation and long-term potentiation (LTP), a likely mechanism for memory storage. One signaling pathway linked to β-AR activation is the cAMP-PKA pathway. PKA is critical for the consolidation of hippocampal long-term memory and for the expression of some forms of long-lasting hippocampal LTP. How does β-AR activation affect the PKA-dependence, and persistence, of LTP elicited by distinct stimulation frequencies? Here, we use in vitro electrophysiology to show that patterns of stimulation determine the temporal phase of LTP affected by β-AR activation. In addition, only specific patterns of stimulation recruit PKA-dependent LTP following β-AR activation. Impairments of PKA-dependent LTP maintenance generated by pharmacologic or genetic deficiency of PKA activity are also abolished by concurrent activation of β-ARs. Taken together, our data show that, depending on patterns of synaptic stimulation, activation of β-ARs can gate the PKA-dependence and persistence of synaptic plasticity. We suggest that this may allow neuromodulatory receptors to fine-tune neural information processing to meet the demands imposed by numerous synaptic activity profiles. This is a form of “metaplasticity” that could control the efficacy of consolidation of hippocampal long-term memories.The hippocampus importantly contributes to memory function in the mammalian brain (Zola-Morgan et al. 1986; Eichenbaum et al. 1990; Otto and Eichenbaum 1992; Phillips and LeDoux 1992; Remondes and Schuman 2004). It has reciprocal connections with numerous cortical areas, including those responsible for high-level integration of spatial and contextual data from the external environment (Lavenex and Amaral 2000). As such, the hippocampus is well positioned to receive and survey a broad range of information and select behaviorally salient data for long-term storage. Activity-dependent enhancement of hippocampal synaptic strength can store information carried in patterns of afferent neural activity (Bliss and Collingridge 1993; Moser et al. 1998; Nathe and Frank 2003; Whitlock et al. 2006). Substantial evidence suggests that long-term potentiation (LTP) of synaptic strength plays important roles in the formation of long-term memory (LTM) (Doyere and Laroche 1992; Bourtchuladze et al. 1994; Abel and Lattal 2001; Genoux et al. 2002). As such, mechanistic studies of LTP have shed valuable light on how the mammalian brain stores new information.The hippocampus receives dense noradrenergic projections from the locus coeruleus, a brain structure that can influence many vital brain functions, including attention, sleep, arousal, mood regulation, learning, and memory (Berridge and Waterhouse 2003). Both α- and β-adrenergic receptor subtypes are present on hippocampal neurons (Morrison and Foote 1986; Berridge and Waterhouse 2003), and noradrenaline (NA) acts on hippocampal β-adrenergic receptors (β-ARs) to facilitate the retention and recall of memory (Izquierdo et al. 1998; Ji et al. 2003; Murchison et al. 2004). In humans, stimulation of the noradrenergic neuromodulatory system enhances memory for emotional stimuli, and inhibition of β-ARs prevents this memory enhancement (Cahill et al. 1994; van Stegeren et al. 1998; O’Carroll et al. 1999).Consistent with the notion that selective enhancement of LTM may occur following β-AR activation, stimulation of β-ARs can also facilitate the persistence of LTP. In areas CA3 and CA1, β-AR activation facilitates the induction of long-lasting LTP when paired with certain patterns of electrical stimulation (Huang and Kandel 1996; Gelinas and Nguyen 2005). However, the mechanisms by which different patterns of stimulation control synaptic responsiveness to β-AR activation are unclear.β-ARs couple to guanine-nucleotide-binding regulatory Gs proteins to stimulate adenylyl cyclase activity and increase intracellular cAMP (Seeds and Gilman 1971; Maguire et al. 1977). A main target of cAMP signaling is activation of cAMP-dependent protein kinase (PKA), a kinase that is required for some forms of long-lasting LTP and for consolidation of hippocampal LTM (Frey et al. 1993; Abel et al. 1997; Nguyen and Woo 2003). Interestingly, the PKA-dependence of hippocampal LTP displays plasticity: Specific temporal patterns of synaptic stimulation, such as repeated and temporally spaced 100-Hz stimulation, elicit LTP that requires PKA for its expression (Woo et al. 2003). Also, spatial “enrichment” can increase the PKA-dependence of LTP in mice, and this is correlated with improved hippocampal memory function (Duffy et al. 2001). However, it is unclear whether activation of β-ARs can critically gate the PKA-dependence of LTP. In this study, we examine the effects of β-AR activation on LTP generated by various patterns of afferent stimulation in area CA1 of the hippocampus, and we determine the role of PKA in these β-AR-modulated forms of LTP.  相似文献   
139.
A commonly used screening tool for psychopathology, the Brief Symptom Inventory, provides normative data for assessing current mental functioning across multiple domains. Using data from 654 psychiatric inpatients, receiver operating characteristic (ROC) analyses were conducted for three scales, Depression, Paranoid Ideation, and Psychoticism. t ratios identified significant group differences on the Depression scale between patients diagnosed with or without depression but no differences on the Paranoid Ideation and Psychoticism scales between patients diagnosed with or without schizophrenia. Area under the curve for Depression was .65, indicating that the scale improved diagnostic prediction somewhat beyond chance; for Paranoid Ideation, the area was .52 and for Psychoticism, the area was .53, indicating that these two scales did not significantly improve diagnostic prediction beyond chance.  相似文献   
140.
We used a systems perspective to examine relationships between adolescents’ perceptions of overall family system functioning and selected parental behaviors. Self-report questionnaire data from 160 ninth and tenth grade students were analyzed using MANCOVA and discriminant analysis. The results showed two parental behaviors, support and monitoring distinguished between types of overall family system functioning. Adolescents in balanced and moderately balanced overall family functioning reported greater parental support, while adolescents in balanced and extreme overall family functioning reported greater parental monitoring. We present the implications of our findings for parent education and assessment.  相似文献   
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