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991.
The social goals and social problem-solving of children who varied in social adjustment were examined in the context of hypothetical ambiguous provocation situations in which provocateurs' emotion displays were systematically manipulated. Children rated the importance of six different social goals and explained how they would solve the problems. Social adjustment was measured with rating and nomination sociometric procedures. Rejected-aggressive, rejected-nonaggressive, average-nonaggressive, and popular-nonaggressive children showed both commonalities and differences in rating the six social goals, the relative importance of the six social goals, and social problem-solving depending on the provocateur's emotion display. When provocateurs were happy, there were few group differences, but when provocateurs were angry or sad, rejected-aggressive children: a) rated hostile/instrumental goals more positively; b) rated prosocial goals less positively; and c) made problem-solving responses that were less friendly than those of other children. Results are discussed in relation to Lemerise and Arsenio's (2000) model of emotion and social information processing.  相似文献   
992.
Children with ADHD have difficulty understanding causal connections and goal plans within stories. This study examined mediators of group differences in story narrations between children ages 7-9 with and without ADHD, including as potential mediators both the core deficits of ADHD (i.e., inattention, disinhibition, planning/working memory) as well measures of phonological processing and verbal skills. Forty-nine children with ADHD and 67 non-referred children narrated a wordless book and completed tasks assessing the core deficits of ADHD, phonological processing, and verbal skills. Results revealed that, although no shorter than those of non-referred children, the narratives of children with ADHD contained fewer elements relating to the story's causal structure and goal plan. Deficits in sustained attention accounted for the most variance in these differences. Results have implications for understanding and ameliorating the academic problems experienced by children with ADHD.  相似文献   
993.
Specific reading disability (SRD) is now widely recognised as often being caused by phonological processing problems, affecting analysis of spoken as well as written language. According to one theoretical account, these phonological problems are due to low-level problems in auditory perception of dynamic acoustic cues. Evidence for this has come from studies showing poor discrimination of frequency-modulated from unmodulated tones. We measured frequency modulation detection limens (FMDLs) in 16 children with specific reading disability (SRD group), 16 children with mild to moderate hearing loss (SNH group) and 16 age-matched controls (CA group) aged 8-14. To obtain information about possible mechanisms used in frequency modulation detection, FMDLs were measured at modulation rates of 2 and 20 Hz, both in the absence and the presence of amplitude modulation, intended to force listeners to rely, if possible, upon phase-locking cues. Although both the SNH and SRD groups showed a trend for elevated FMDLs at both 2 and 20 Hz, these differences reached statistical significance for the SNH group alone. However, the SNH group had no evidence of literacy impairments. This study thus shows that impairments in perceiving dynamically modulated auditory stimuli do not necessarily lead to difficulty in learning to read.  相似文献   
994.
The present study compared the automaticity levels of persons who stutter (PWS) and persons who do not stutter (PNS) on a practiced finger sequencing task under dual task conditions. Automaticity was defined as the amount of attention required for task performance. Twelve PWS and 12 control subjects practiced finger tapping sequences under single and then dual task conditions. Control subjects performed the sequencing task significantly faster and less variably under single versus dual task conditions while PWS' performance was consistently slow and variable (comparable to the dual task performance of control subjects) under both conditions. Control subjects were significantly more accurate on a colour recognition distracter task than PWS under dual task conditions. These results suggested that control subjects transitioned to quick, accurate and increasingly automatic performance on the sequencing task after practice, while PWS did not. Because most stuttering treatment programs for adults include practice and automatization of new motor speech skills, findings of this finger sequencing study and future studies of speech sequence learning may have important implications for how to maximize stuttering treatment effectiveness. Educational objectives: As a result of this activity, the participant will be able to: (1) Define automaticity and explain the importance of dual task paradigms to investigate automaticity; (2) Relate the proposed relationship between motor learning and automaticity as stated by the authors; (3) Summarize the reviewed literature concerning the performance of PWS on dual tasks; and (4) Explain why the ability to transition to automaticity during motor learning may have important clinical implications for stuttering treatment effectiveness.  相似文献   
995.
Estes and Maddox (2002) suggested that the word frequency mirror effect in episodic recognition memory might be due to word likeness rather than to the frequency of experience with a word per se. We examined their suggestion using a factorial manipulation of frequency and neighborhood density, a measure used in lexical memory research to measure orthographic word likeness. For study with no specified task, main effects of density and frequency were in the mirror order, confirming the hypothesized mirror effect of word likeness but not its role in producing the frequency mirror effect. Lexical decision study increased the size of both mirror effects, even though the density manipulation had a negligible effect on lexical decision performance for words. Post hoc analyses showed that neither mirror effect could be explained by differences in lower order measures of word likeness (letter and bigram frequency). The joint orders of frequency and density results were mirrored across new and old conditions in accordance with attention likelihood theory (ALT), but density effects on z-ROC slope suggest that ALT may require extension to accommodate the effect of word likeness on response confidence.  相似文献   
996.
This study investigated memory from interrupted visual searches. Participants conducted a change detection search task on polygons overlaid on scenes. Search was interrupted by various disruptions, including unfilled delay, passive viewing of other scenes, and additional search on new displays. Results showed that performance was unaffected by short intervals of unfilled delay or passive viewing, but it was impaired by additional search tasks. Across delays, memory for the spatial layout of the polygons was retained for future use, but memory for polygon shapes, background scene, and absolute polygon locations was not. The authors suggest that spatial memory aids interrupted visual searches, but the use of this memory is easily disrupted by additional searches.  相似文献   
997.
It has been established that memorizing common problems and their solutions underlies cognitive skill development, and that there are substantial age deficits in the rate of this learning. In a between-groups design, the authors compared learning rates for the same set of problems in skill (SK) training and paired-associate (PA) training. The authors found main effects due to condition (PA problems were acquired earlier) and to age (older adults' learning was delayed), but no condition-by-age interaction. The authors concluded that the age deficit in SK can be accounted for by the age deficit in associative memory; no further explanation is needed. The authors also analyzed fast and slow retrieves in SK and PA, and found that the frequency of fast retrieves did not differ in the two conditions. The overall advantage of PA was due to the occurrence of slow retrieves, which were absent in SK presumably because the skill algorithm displaces slow, explicit memory search in SK, but not fast, familiarity-based retrieval.  相似文献   
998.
The authors examined age differences in adults' allocation of effort when reading text for either high levels of recall accuracy or high levels of efficiency. Participants read a series of sentences, making judgments of learning before recall. Older adults showed less sensitivity than the young to the accuracy goal in both reading time allocation and memory performance. Memory accuracy and differential allocation of effort to unlearned items were age equivalent, so age differences in goal adherence were not attributable to metacognitive factors. However, comparison with data from a control reading task without monitoring showed that learning gains among older adults across trial were reduced relative to those of the young by memory monitoring, suggesting that monitoring may be resource consuming for older learners. Age differences in the responsiveness to (information-acquisition) goals could be accounted for, in part, by independent contributions from working memory and memory self-efficacy. Our data suggest that both processing capacity ("what you have") and beliefs ("knowing you can do it") can contribute to individual differences in engaging resources ("what you do") to effectively learn novel content from text.  相似文献   
999.
We examined the ontogeny of the corticosterone response to (+)-methamphetamine in neonatal rats. In experiment-1, animals were injected with 10 mg/kg of (+)-methamphetamine or saline and plasma corticosterone levels were examined in separate groups 30 or 105 min later on postnatal day (P) 1, 3, 5, 7, 9, 11, 13, 15, 17, or 19. The adrenal response to methamphetamine was best described by a U-shaped function with the nadir of corticosterone release occurring between P7 and P13. Experiment-2 was similar except that the effect of four consecutive days of exposure to (+)-methamphetamine (four times daily at 2 h intervals with 10 mg/kg) was assessed with a single final dose early on the fifth day (i.e. P1-5, 3-7, 5-9, 7-11, 9-13, 11-15, 13-17, 15-19). The 30 min corticosterone response after multiple methamphetamine doses was augmented compared to single exposures, with the exception of the two earliest dosing intervals ending on P5 and P7, where the responses were lower. In addition, at 105 min, the levels of corticosterone were attenuated relative to a single drug administration. With the exception of animals receiving methamphetamine from P15 to P19, thymus weights were unaffected. The data demonstrate that (+)-methamphetamine is a robust activator of corticosterone release in developing animals and this release is extensively modified by age and previous drug exposure.  相似文献   
1000.
Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were used to investigate the factor structure of coping in mothers with high levels of life stress. In Study 1, EFA of the Coping Orientation to Problems Experienced (C. S. Carver, M. F. Scheier, & J. K. Weintraub, 1989) in a sample of mothers of full-term or very low birth weight 2-year-old children yielded 7 reliable coping factors. Each factor accounted for significant variance in at least 1 of 6 outcomes measuring maternal-child well-being. In Study 2, CFA was used to cross-validate the EFA model on the basis of the responses of mothers of 2-year-old children with prenatal polysubstance exposure. CFA results revealed a moderately good fit, confirming the factor structure in a 2nd, independent sample of mothers with high levels of life stress.  相似文献   
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