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931.
This research stems from our program of work that focuses on understanding how students regulated their emotions related to testing. The primary goal for this study was to incorporate the approach/ avoidance motives into a model of emotional regulation related to testing. In addition, a secondary goal was to report on efforts at construct validation of the scores obtained during the refinement of the Emotional Regulation Related to Testing (ERT) Scale. Our results suggest that underlying beliefs, such as approach/avoid motives and the cognitive-appraisal process, of the ERT had both direct and indirect effects to both pleasant and unpleasant emotions related to testing. In addition, the ERT accounted for 56% of the variance in Pleasant and 87% of Unpleasant Test Emotions.  相似文献   
932.
N-Methyl-D-aspartate receptors (NMDARs) mediate certain forms of synaptic plasticity and learning. We used a touchscreen system to assess NR2A subunit knockout mice (KO) for (1) pairwise visual discrimination and reversal learning and (2) acquisition and extinction of an instrumental response requiring no pairwise discrimination. NR2A KO mice exhibited significantly retarded discrimination learning. Performance on reversal was impaired in NR2A KO mice during the learning phase of the task; with no evidence of heightened perseverative responses. Acquisition and extinction of an instrumental behavior requiring no pairwise discrimination was normal in NR2A KO mice. The present findings demonstrate a significant and selective deficit in discrimination learning following loss of NR2A.  相似文献   
933.
The theory of memory reconsolidation relates to the hypothesized restabilisation process that occurs following the reactivation of a memory through retrieval. Thus the demonstration of reactivation-dependent amnesia for a previously acquired memory is a prerequisite for showing that such a memory undergoes reconsolidation. Here we show that the appetitive Pavlovian representations that underlie Pavlovian approach and Pavlovian-instrumental transfer are destabilized following their retrieval. This reactivation-dependent amnesia demonstrates that the general motivational or incentive properties of appetitive conditioned stimuli, as well as their conditioned reinforcing properties, can be reduced by blocking memory reconsolidation.  相似文献   
934.
OBJECTIVE AND METHODS: The comparative validity of the Eating Disorder Examination Questionnaire (EDE-Q) (22 items) and SCOFF (five items) in screening for cases of the more commonly occurring eating disorders was examined in a primary care sample of young adult women (n=257). Diagnoses were confirmed in a sub-group of interviewed participants (n=147). RESULTS: Twenty-five cases, primarily variants of bulimia nervosa (BN) not meeting formal diagnostic criteria, were identified in the interviewed sample. An EDE-Q global score of >or= 2.80 yielded the optimal trade-off between sensitivity (Se) (0.80) and specificity (Sp) (0.80) (positive predictive value (PPV)=0.44), whereas a score of two or more positive responses on the SCOFF was optimal (Se=0.72, Sp=0.73, PPV=0.35). Validity coefficients for both measures varied as a function of participants' age and body weight, although these effects were more pronounced for the SCOFF. CONCLUSIONS: Both measures performed well in terms of their ability to detect cases and to exclude non-cases of the more commonly occurring eating disorders in a primary care setting. The EDE-Q performed somewhat better than the SCOFF and was more robust to effects on validity of age and weight. These findings need to be weighed against the advantage of the SCOFF in terms of its brevity.  相似文献   
935.
Background Early, intensive phonological awareness and phonics training is widely held to be beneficial for children with poor phonological awareness. However, most studies have delivered this training separately from children's normal whole‐class reading lessons. Aims We examined whether integrating this training into whole class, mixed‐ability reading lessons could impact on children with poor phonological awareness, whilst also benefiting normally developing readers. Sample Teachers delivered the training within a broad reading programme to whole classes of children from Reception to the end of Year 1 (N = 251). A comparison group of children received standard teaching methods (N = 213). Method Children's literacy was assessed at the beginning of Reception, and then at the end of each year until 1 year post‐intervention. Results The strategy significantly impacted on reading performance for normally developing readers and those with poor phonological awareness, vastly reducing the incidence of reading difficulties from 20% in comparison schools to 5% in intervention schools. Conclusions Phonological and phonics training is highly effective for children with poor phonological awareness, even when incorporated into whole‐class teaching.  相似文献   
936.
A considerable amount of research has uncovered heuristics that the visual system employs to keep track of objects through periods of occlusion. Relatively little work, by comparison, has investigated the online resources that support this processing. We explored how attention is distributed when featurally identical objects become occluded during multiple object tracking. During tracking, observers had to detect small probes that appeared sporadically on targets, distracters, occluders, or empty space. Probe detection rates for these categories were taken as indexes of the distribution of attention throughout the display and revealed two novel effects. First, probe detection on an occluder’s surface was better when either a target or distractor was currently occluded in that location, compared to when no object was behind that occluder. Thus even occluded (and therefore invisible) objects recruit object-based attention. Second, and more surprising, probe detection for both targets and distractors was always better when they were occluded, compared to when they were visible. This new attentional high-beams effect indicates that the ability to track through occlusion, though seemingly effortless, in fact requires the active allocation of special attentional resources.  相似文献   
937.
In two masked repetition priming experiments with letter stimuli, the positions of prime and target stimuli were varied horizontally from fixation. Priming effects did not interact with position when prime and target location covaried (Experiment 1A) but diminished with increasing prime eccentricity when targets were always centrally located (Experiment 1B). Two accounts of this pattern of priming effects were proposed that postulate two different mechanisms over and above effects of visual acuity. The integration account postulates degree of separation of prime and target stimuli as the critical factor, and the attentional account postulates spatial attention as the critical factor. The results of Experiment 2, in which prime and target positions were manipulated orthogonally, were in favor of the attentional account. Repetition priming did not vary as a function of whether or not primes and targets appeared at the same location, but target processing was facilitated independently of priming when targets appeared at the same location as primes, especially in the right visual field.  相似文献   
938.
The progressive demasking (PDM) task is a perceptual identification task using degraded stimulus presentation procedures, but with the advantage of providing response time (RT) measures on each trial. Participants simply press a response button whenever they recognize a word. In this article, we present newly developed, easy-to-use freeware for PDM. Considering the difficulty of programming such a paradigm with standard experimental software, we developed a program based on high-level C libraries to be executed on Windows XP computers. The program execution is millisecond accurate forRT measurements and generates the fewest possible display duration errors.  相似文献   
939.
Pre‐play discussion consistently increases cooperation in dilemma interactions. Most explanations of this “cheap‐talk” effect are based on either commitment or group solidarity effects. Because discussion about the upcoming dilemma allows participants to make promises and creates group solidarity, the 2 explanations are often confounded. This paper aims to clarify past results by having participants engage in an unrelated discussion prior to a dilemma interaction. We find that solidarity effects can be induced by minimal group categorizations, but are relatively weak. Discussions involving consequential but unrelated coordination tasks are shown to prime cooperative norms and increase cooperation with both in‐group and out‐group members. Our findings suggest that cheap talk may work for even cheaper reasons than previously thought.  相似文献   
940.
The reproducibility of experimental outcomes depends on consistent control of independent variables. In food-maintained operant performance, it is of utmost importance that the quantity of food delivered is reliable. To that end, some commercial food pellet dispensers have add-on attachments to sense the delivery of pellets. Not all companies, however, offer such add-ons. Aside from availability, cost and temporary reduction in throughput may be a problem for smaller labs. The present paper outlines our recent development of a simple, inexpensive infrared device to detect and confirm the delivery of pellets. The in-line construction of the detector routes the falling pellet through a barrel so that it passes between an infrared emitter and receiver. The circuitry was designed to be compatible with all commercially available behavioral measurement systems, and so may be retrofit to any existing system. Our tests with the detector so far have shown that it is 100% accurate in detecting pellet delivery. The individual unit cost is approximately 25 dollars. The low cost and versatility of the device offer an easy method to ensure the integrity of food delivery in operant settings.  相似文献   
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