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951.
952.
The goal of the present study was twofold: to examine the influence of two amodal properties, co-location and temporal synchrony, on infants' associating a sight with a sound, and to determine if the relative influence of these properties on crossmodal learning changes with age. During familiarization 2-, 4-, 6- and 8-month-olds were presented two toys and a sound, with sights and sounds varying with respect to co-location and temporal synchrony. Following each familiarization phase infants were given a paired preference test to assess their learning of sight-sound associations. Measures of preferential looking revealed age-related changes in the influence of co-location and temporal synchrony on infants' learning sight-sound associations. At all ages, infants could use temporal synchrony and co-location as a basis for associating an auditory with a visual event and, in the absence of temporal synchrony, co-location was sufficient to support crossmodal learning. However, when these cues conflicted there were developmental changes in the influence of these cues on infants' learning auditory-visual associations. At 2 and 4 months infants associated the sounds with the toy that moved in synchrony with the sound's rhythm despite extreme violation of co-location of this sight and sound. In contrast, 6- and 8-month-olds did not associate a specific toy with the sound when co-location and synchrony information conflicted. The findings highlight the unique and interactive effects of distinct amodal properties on infants' learning arbitrary crossmodal relations. Possible explanations for the age shift in performance are discussed.  相似文献   
953.
Peripherally administered or released substances that modulate memory storage, but do not freely enter the brain, may produce their effects on memory by activating peripheral receptors that send messages centrally through the vagus nerve. Indeed, vagus nerve stimulation enhances memory performance, although it is unclear whether this effect is due to the activation of vagal afferents or efferents. To eliminate the possible influence of descending fibers on memory storage processes, rats were implanted with cuff electrode/catheter systems along the left cervical vagus. Forty-eight hours following surgery, each animal received a 3.0-μl infusion (1.0 μl/min) of either lidocaine hydrochloride (75.0 mM) or isotonic saline below the point of stimulation. Animals were then trained 10 min later on an inhibitory-avoidance task with a 0.75-mA, 1.0-s foot shock. Sham stimulation or vagus nerve stimulation (0.5-ms biphasic pulses; 20.0 Hz; 30 s; 0.2, 0.4, or 0.8 mA) was administered immediately after training. Memory, tested 24 h later, was enhanced by stimulation whether descending vagus nerve fibers were inactivated or not. Both lidocaine- and saline-infused groups showed an intensity-dependent, inverted-U-shaped pattern of retention performance, with the greatest effect observed for 0.4 mA (U= 9,p< .05, andU= 7,p< .01, respectively). Additionally, animals that received lidocaine infusions, but no vagus nerve stimulation, showed impaired memory compared to the performance of saline-infused control animals (U= 11,p< .05). Together, these findings suggest that vagal afferents carry messages about peripheral states that lead to the modulation of memory storage and that the memory-enhancing effect produced by vagus nerve stimulation is not mediated via the activation of vagal efferents.  相似文献   
954.
Past research indicates that the anticholinergic drug scopolamine disrupts memory and environmentally induced hypoalgesia in rats. The present study examined the impact of the centrally active cholinesterase inhibitor physostigmine, which enhances memory and central cholinergic activity, on brief shock-induced hypoalgesia on the tail-flick test using Sprague–Dawley rats. It is reported that physostigmine (0.1 mg/kg) potentiates the magnitude of this hypoalgesia. Contrary to past research, our results showed that omission of baseline testing did not eliminate hypoalgesia or its potentiation by physostigmine. Similar to its effects on memory, physostigmine (0.04, 0.1, and 0.25 mg/kg) has a nonmonotonic impact on brief shock-induced hypoalgesia; low doses potentiated hypoalgesia (0.1 mg/kg), whereas a high dose (0.25 mg/kg) disrupted it. These results provide further evidence that the cholinergic system indirectly affects pain reactivity by modulating the memory of the aversive event.  相似文献   
955.
This paper reviews evidence that behavioral family interventions are effective at improving child-rearing in distressed families and families with children exhibiting disruptive behavior. Essential therapeutic strategies offered within a collaborative therapeutic process are identified. Exemplary materials for parents and clinicians are identified. Differences between behavioral family interventions and two popular press parenting approaches are highlighted, including the lack of empirical support for these widely used programs and the advice they offer which runs counter to behavioral approaches. Recommendations are offered for combining behavioral family interventions with other empirically supported approaches, promoting more widespread use of empirically supported treatments, such as behavioral family interventions, and the need for a public health perspective on family functioning, involving collaboration among clinicians, policy makers, and researchers.  相似文献   
956.
957.
We examined whether, as predicted by research on child effects, we could generate hypotheses about the function of student problem behavior by observing the amount of attention teachers provided to students. In the first phase of the study, we observed the amount of attention teachers distributed among small groups of students who exhibited problem behavior in individual or small-group instructional settings (problem behavior presumably maintained by attention or escape). Based on the amount of attention each student received, we generated hypotheses about the function of his or her problem behavior. In the second phase of the study, we determined the accuracy of these predictions by conducting a brief functional assessment with each student. Results confirmed that, for 14 of the 15 students, we were able to generate accurate hypotheses about the function of their problem behavior. These results suggest the potential efficacy of using the amount of attention teachers distribute among groups of students to generate empirically based hypotheses about the function of student problem behavior maintained by attention and/or escape. These results also illustrate the efficiency of this procedure; by observing teacher behavior, we were able to generate hypotheses about the function of problem behavior for several students at one time.  相似文献   
958.
959.
短时动作记忆的容量和精确度与动作学习的关系   总被引:3,自引:0,他引:3  
该研究采用实验室实验法,被试自我报告分析及调查访问法,以三个年龄(10岁、14岁、18岁)组学生及专项运动员为实验对象,揭示短时动作记忆的容量和精确度及其与动作学习指数的关系。结果表明:(1)被试的短时动作记忆容量为“5±2”,短时动作记忆的容量与动作学习的练习次数相联系;短时动作记忆的精确度与第一次动作练习的准确度相联系。(2)短时动作记忆的容量有随年龄增长而递增的趋势。(3)运动员与非运动员被试对于同类动作学习的练习次数存在显著性差异。  相似文献   
960.
Investigated was a deficit in avoidance learning in situations of competing rewards and punishments in boys with behavior disorders. This learning style has been found to differentiate adults with psychopathy and controls and has been labeled reward dominance. The present study investigated the reward dominance paradigm in a group of 9- to 13-year-old boys with disruptive behavior disorders (N=21) and a normal control group (N=22). Subjects played four computer games programmed to provide the subject with a steadily decreasing ratio of rewards to punishments. Although the groups did not differ initially on the number of trials played, significant group differences emerged when measures of anxiety were included in the analysis. That is, boys with disruptive behavior disorders played more trials (reward dominance) only when the effect of anxiety was controlled. These findings are consistent with Gray's biobehavioral theory of personality and are also consistent with research indicating that anxiety is an important marker for a distinct subgroup of children with behavior problems.  相似文献   
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