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991.
Perfectionism is hypothesized to contribute to the etiology of anorexia nervosa (AN). However, there is little research regarding whether individuals with AN can be classified according to maladaptive (e.g., evaluative concerns) and adaptive (e.g., high personal standards) facets of perfectionism that predict distinct outcomes and might warrant different intervention approaches. In this study, a latent profile analysis was conducted using data from adults with AN (n?=?118). Frost Multidimensional Perfectionism Scale (Frost et al. Cognitive Therapy and Research, 14(5), 449–46, 1990) subscales were used to identify subgroups differing according to endorsed perfectionism features (e.g., adaptive and maladaptive perfectionism). Generalized linear models were used to compare subgroups on eating disorder and affective symptoms measured through questionnaire and ecological momentary assessment. Four subgroups were identified: (a) Low Perfectionism; (b) High Adaptive and Maladaptive Perfectionism; (c) Moderate Maladaptive Perfectionism; and (d) High Maladaptive Perfectionism. Subgroups differed on overall eating disorder symptoms (p?<?.001), purging (p?=?.005), restrictive eating (p?<?.001), and body checking (p?<?.001) frequency, depressive (p?<?.001) and anxiety (p?<?.001) symptoms, and negative (p?=?.001) and positive (p?<?.001) affect. The Low Perfectionism group displayed the most adaptive scores and the Moderate and High Maladaptive Perfectionism groups demonstrated the most elevated clinical symptoms. The High Adaptive and Maladaptive Perfectionism group demonstrated low affective disturbances, but elevated eating disorder symptoms. Results support the clinical significance of subtyping according to perfectionism dimensions in AN. Research is needed to determine if perfectionism subtyping can enhance individualized treatment targeting in AN.  相似文献   
992.
993.
The basolateral amygdala (BLA) is extensively implicated in emotional learning and memory. The current study investigated the contribution of cholinergic afferents to the BLA from the nucleus basalis magnocellularis in influencing aversive learning and memory. Sprague-Dawley rats were given permanent unilateral phthalic acid (300 ng) lesions of the nucleus basalis magnocellularis and were chronically implanted with cannulas aimed at the ipsilateral BLA. Lesioned rats showed a pronounced inhibitory avoidance task retention deficit that was attenuated by acute posttraining infusions of the muscarinic cholinergic agonist oxotremorine (4 ng) or the indirect agonist physostigmine (1 microg) into the BLA. Continuous multiple-trial inhibitory avoidance training and testing revealed that lesioned rats have a mild acquisition deficit, requiring approximately 1 additional shock to reach the criterion, and a pronounced consolidation deficit as indicated by a shorter latency to enter the shock compartment on the retention test. Because lesioned rats did not differ from sham-operated controls in performance on a spatial water maze task or in shock sensitivity, it is not likely that the memory impairments produced by the phthalic acid lesions are due to any general sensory or motor deficits. These findings suggest that the dense cholinergic projection from the nucleus basalis magnocellularis to the BLA is involved in both the acquisition and the consolidation of the aversive inhibitory avoidance task.  相似文献   
994.
Until recently, the challenges inherent in measuring comprehension have impeded our ability to predict the course of language acquisition. The present research reports on a longitudinal assessment of the convergent and predictive validity of the MacArthur-Bates Communicative Development Inventories: Words and Gestures (CDI: WG; Fenson et al., 1994, 1993, 2007) and the Computerized Comprehension Task (CCT; Friend & Keplinger, 2003, 2008). The CDI: WG and the CCT evinced good convergent validity; however, the CCT better predicted subsequent parent reports of language production. Language sample data in the 3rd year confirm this finding: The CCT accounted for 24% of the variance in unique word use. These studies provide evidence for the utility of a behavior-based approach to predicting the course of language acquisition into production.  相似文献   
995.
Adult (age 30) educational, economic, and social-emotional adjustment outcomes were investigated for participants in the Abecedarian Project, a randomized controlled trial of early childhood education for children from low-income families. Of the original 111 infants enrolled (98% African American), 101 took part in the age 30 follow-up. Primary indicators of educational level, economic status, and social adjustment were examined as a function of early childhood treatment. Treated individuals attained significantly more years of education, but income-to-needs ratios and criminal involvement did not vary significantly as a function of early treatment. A number of other indicators were described for each domain. Overall, the findings provide strong evidence for educational benefits, mixed evidence for economic benefits, and little evidence for treatment-related social adjustment outcomes. Implications for public policy are discussed.  相似文献   
996.
We recorded electroencephalogram (EEG; 6-9 Hz) and heart rate (HR) from infants at 5 and 10 months of age during baseline and performance on the looking A-not-B task of infant working memory (WM). Longitudinal baseline-to-task comparisons revealed WM-related increases in EEG power (all electrodes) and EEG coherence (medial frontal-occipital electrode pairs) at both ages. WM-related decreases in HR were only present at 5 months, and WM-related increases in EEG coherence became more localized by 10 months. Regression analyses revealed that baseline-to-task changes in psychophysiology accounted for variability in WM performance at 10 but not 5 months. HR and EEG power (medial frontal and lateral frontal electrodes) were unique predictors of variability in 10-month WM performance. These findings are discussed in relation to frontal lobe development and represent the first comprehensive longitudinal analysis of age-related changes in the behavioral and psychophysiological correlates of WM.  相似文献   
997.
Infrequent count data in psychological research are commonly modelled using zero-inflated Poisson regression. This model can be viewed as a latent mixture of an "always-zero" component and a Poisson component. Hurdle models are an alternative class of two-component models that are seldom used in psychological research, but clearly separate the zero counts and the non-zero counts by using a left-truncated count model for the latter. In this tutorial we revisit both classes of models, and discuss model comparisons and the interpretation of their parameters. As illustrated with an example from relational psychology, both types of models can easily be fitted using the R-package pscl.  相似文献   
998.
Anxiety in children age 8 years and above has been successfully treated with cognitive behavioral therapy (CBT). However, the efficacy of CBT for anxious children ages 4-7 years has not, to date, been fully investigated. This paper piloted a CBT intervention targeting child anxiety that was delivered exclusively to parents of 26 children with anxiety symptoms ages 4-7 years. The intervention consisted of four 2-hour group sessions of four to six parents (couples). These group sessions were followed by four individual telephone sessions, once per week across a 4-week period. The pre- and postintervention assessment involved measures of multiple constructs of child anxiety (anxiety symptoms, children's fears, behavioral inhibition, and internalizing symptoms) from multiple informants (parents, children, and teachers). Parents also reported parenting strategies they were likely to use to manage their children's anxiety pre- and postintervention. Results indicated a significant decrease in child anxiety and behavioral inhibition as reported by parents and teachers. Furthermore, mothers reported significant increases in their use of positive reinforcement, and modeling and reassurance, and a significant decrease in their use of reinforcement of dependency directly after treatment. Taken together, parent-directed CBT appears to be an effective approach for treating children ages 4-7 years with anxiety symptoms. Limitations of the current research are discussed.  相似文献   
999.
A sophisticated and flexible understanding of the equals sign (=) is important for arithmetic competence and for learning further mathematics, particularly algebra. Research has identified two common conceptions held by children: the equals sign as an operator and the equals sign as signaling the same value on both sides of the equation. We argue here that, in addition to these two conceptions, the notion of substitution is also an important part of a sophisticated understanding of mathematical equivalence. We provide evidence from a cross-cultural study in which English and Chinese children were asked to rate the "cleverness" of operational, sameness, and substitutive definitions of the equals sign. A principal components analysis revealed that the substitutive items were distinct from the sameness items. Furthermore, Chinese children rated the substitutive items as 'sort of clever' or 'very clever', whereas English children rated them as not so clever, suggesting that the notion of substitution develops differently across the two countries. Implications for developmental models of children's understanding of equivalence are discussed.  相似文献   
1000.
Participants with albinism have reduced vision and nystagmus with reduced foveation times. This prospective study evaluated driving in 12 participants with albinism and 12 matched controls. Participants drove a vehicle simulator through a virtual rural course in sunny and foggy conditions. Under sunny conditions, participants with albinism showed a narrower preferred minimum safety boundary during car-following tasks than did controls, but there was no difference under foggy conditions. Their driving did not differ significantly from that of controls when approaching a stop sign or when choosing gap size between oncoming vehicles when crossing an intersection. However, when compared to control drivers, participants with albinism had a decreased minimum safety boundary for car-following that should be included in counseling regarding driving safety.  相似文献   
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