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931.
This investigation examined the validity of using ratings of perceived exertion (RPE) to regulate intensity during resistance exercise. 19 male (M age = 22.2 yr., SD = 2.7) and 19 female (M age = 21.4 yr., SD = 2.3) participants estimated exertion when performing the knee extension at 40% to 90% of one-repetition maximum. One week later, participants were asked to produce weights for the knee extension that elicited the feelings of exertion associated with 9, 13, and 17 on the Borg RPE scale. The weight produced at 9, 13, and 17 during the production session was compared to the weight lifted at each RPE during the estimation session. The effect sizes associated with the differences in weight lifted across sessions at each RPE were generally small in magnitude, especially at the higher intensities (ES = .40, -.09, .15, respectively). The results of this investigation support the use of RPE as a method of prescribing the intensity of resistance exercise.  相似文献   
932.
933.
The present study evaluated the utility of parent- and child-reported social fears for reaching a diagnosis of social phobia in youth. The diagnostic utility of (a) the number of fears and (b) specific feared social situations was examined. The sample included 140 youth and their parents: youth diagnosed with social phobia (n=50), youth diagnosed with generalized anxiety disorder or separation anxiety disorder but not social phobia (n=49), and youth without an anxiety disorder (n=41). Youth and their parents were interviewed separately using the Anxiety Disorders Interview Schedule for Children and Parents. Analyses indicate that a cut score of 4 parent-endorsed social fears optimally distinguished youth with and without social phobia. Analyses of child-reported fears did not identify a meaningful cut score. Conditional probability and odds ratio analyses indicated that several specific social fears have high diagnostic efficiency, and others were found to have limited diagnostic efficiency. Results are discussed with regard to informing diagnostic interviews and diagnostic systems for social phobia in youth.  相似文献   
934.
Four experiments demonstrate category congruency priming by subliminal prime words that were never seen as targets in a valence-classification task (Experiments 1, 2, and 4) and a gender-classification task (Experiment 3). In Experiment 1, overlap in terms of word fragments of one or more letters between primes and targets of different valences was larger than between primes and targets of the same valence. In Experiments 2 and 3, the sets of prime words and target words were completely disjoint in terms of used letters. In Experiment 4, pictures served as targets. The observed subliminal priming effects for novel primes cannot be driven by partial analysis of primes at the word-fragment level; they suggest instead that primes were processed semantically as whole words contingent upon prime duration.  相似文献   
935.
We conducted this study to determine the relationship between math preference and mastery for five middle school students with autism spectrum disorders. We randomly presented several math addition and subtraction problem formats to determine the students’ preferences. Results indicated that preference was idiosyncratic across students. In addition, preference was not related to mastery in some students. Results are discussed within a theoretical framework of matching law. Implications for practitioners are discussed.
Devender R. BandaEmail:
  相似文献   
936.
Perceived heaviness has been shown to be specific to an object’s rotational inertia (I ), its resistance to rotational acceleration. According to the kinematic specification of dynamics (KSD) principle, we hypothesized that I is optically specified by rotational kinematics. Using virtual depictions of wielded objects, we investigated whether the visually detected rotational kinematics of wielded objects would influence perceived heaviness in a manner consistent with the inertial model of heaviness perception. We scaled the virtual object’s movement so that it rotated more or less than its wielded counterpart, specifying lower and higher I, respectively. Perceived heaviness was inversely related to the rotational scaling factor, consistent with a KSD interpretation of the inertial model.  相似文献   
937.
Exposure to an enriched environment (EE) has been shown to induce cortical plasticity. Considerable amount of research is focused on the effects of EE in the hippocampus; however, effects of EE on other brain regions and the mechanisms involved are not well known. To investigate this, we induced cortical plasticity by placing mice in an EE for one month and measured the effects of EE in the anterior cingulate cortex (ACC). Here, we show that EE enhanced the expression of the plasticity gene, egr-1, in the ACC of EE animals accompanied by enhanced cingulate long-term potentiation (LTP) and decreased cingulate long-term depression (LTD). The increased NMDA receptor NR2B/NR2A subunits current ratio is associated with the plasticity seen in the ACC while total protein levels remain unchanged. Furthermore, behavioral experiments show that these mice exposed to EE demonstrate enhanced responses to acute and long-term inflammation. Our findings suggest that exposure to EE alters physiological properties within the ACC which results in enhanced responses to inflammation.  相似文献   
938.
Context-induced drug craving and continuous drug use manifest the critical roles of specific memory episodes associated with the drug use experiences. Drug-induced conditioned place preference (CPP) in C57BL/6J mouse model, in this regard, is an appropriate behavioral paradigm to study such drug use-associated memories. Requirement of protein synthesis in various forms of long-term memory formation and storage has been phylogenetically demonstrated. This study was undertaken to study the requirement of protein synthesis in the learning and memory aspect of the conditioned place preference induced by cocaine and methamphetamine, two abused drugs of choice in local area. Since pCREB has been documented as a candidate substrate for mediating the drug-induced neuroadaptation, the pCREB level in hippocampus, nucleus accumbens, and prefrontal cortex was examined for its potential participation in the formation of CPP caused by these psychostimulants. We found that cocaine (2.5 and 5.0 mg/kg/dose)-induced CPP was abolished by the pretreatment of anisomycin (50 mg/kg/dose), a protein synthesis inhibitor, whereas methamphetamine (0.5 or 1.0 mg/kg/dose)-induced CPP was not affected by the anisomycin pretreatment. Likewise, cocaine-induced CPP was mitigated by another protein synthesis inhibitor, cycloheximide (15 mg/kg/injection) pretreatment, whereas methamphetamine-induced CPP remained intact by such pretreatment. Moreover, anisomycin treatment 2h after each drug-place pairing disrupted the cocaine-induced CPP, whereas the same treatment did not affect methamphetamine-induced CPP. An increase of accumbal pCREB level was found to associate with the learning phase of cocaine, but not with the learning phase of methamphetamine. We further found that intraaccumbal CREB antisense oligodeoxynucleotide infusion diminished cocaine-induced CPP, whereas did not affect the methamphetamine-induced CPP. Taken together, these data suggest that protein synthesis and accumbal CREB phosphorylation are essential for the learning and consolidation of the cocaine-induced CPP, whereas methamphetamine-induced CPP may be unrelated to the synthesis of new proteins.  相似文献   
939.
Researchers have postulated 2 mechanisms for processing auditory motion: a direct mechanism processing motion itself and an indirect mechanism sensitive to location over discrete points in time. Measuring aftereffects of azimuthal motion by nulling entails scattered responding, which is attributed to a conflict between direct and indirect mechanisms. In this experiment, the author obtained nulls following adaptation to changing sound level, a property of approaching or receding sound sources, and for nonadaptation. Test stimuli ranged in duration from 1.0 to 2.5 s. Longer test stimuli evinced reductions in both changing-loudness aftereffects and the associated response scatters. However, the latter matched the nonadaptation response scatters. The author suggests that judging longer test stimuli is easier, so an indirect mechanism need not be invoked. Simplified processing of changing sound level may underlie the rapid responses required for potential collision.  相似文献   
940.
In this study, we sought to explore the diagnostic accuracy of the Personality Assessment Inventory (PAI; Morey, 1991) Validity scales (Negative Impression Management [NIM] and Positive Impression Management [PIM]) and indexes (Malingering index, Defensiveness index [DEF]; Morey, 1993, 1996; Cashel Discriminant Function; Cashel, Rogers, Sewell, & Martin-Cannici, 1995; and Rogers Discriminant Function [RDF]; Rogers, Sewell, Morey, & Ustad, 1996) to identify differences in profiles completed by psychiatric inpatients under standardized instructions (Time 1) and after random assignment (Time 2) to a fake good (n=21), fake bad (n=20), or retest (n=21) scenario. Repeated measures analysis of variance revealed a significant interaction effect. Whereas the retest group did not show any significant changes on the PAI variables from Time 1 to Time 2, both faking groups showed changes in expected directions. Discriminant function analyses revealed that NIM, RDF, and lower scores on DEF best differentiated between the faking bad and retest groups. PIM was the only nonredundant significant score discriminating the faking good and retest groups. Cutoffs for these scales and indexes established in prior research were supported using diagnostic efficiency statistics. Results suggest that NIM and RDF in faking bad scenarios and PIM in faking good scenarios are most sensitive to unsophisticated attempts to dissimulate by inpatient psychiatric patients.  相似文献   
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