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991.
A total of 405 children of 5–18 years of age were administered performance-based and parent-report measures of executive function (EF), and measures of motor, attention, reading, and mathematics performance. Attention, reading, and mathematics abilities were associated with a parent-report measure of EF. Reading and mathematics abilities were also associated with performance-based measures of EF, including the Animal Sorting, Inhibition, and Response Set subtests of the Developmental NEuroPSYchological Assessment-II. In contrast, motor functioning was only associated with performance-based measures of EF. Findings suggest that different constructs of EF are measured by parent-report versus performance-based measures, and that these different constructs of EF are associated with different neurodevelopmental processes.  相似文献   
992.
The present study examined the acquisition and transmission of tool making and use in a group of chimpanzees. We set up a piece of apparatus that provided orange juice in an outdoor compound for a group of nine chimpanzees. Although they could reach the juice with their hands, eight of the nine subjects used tools. Fifteen kinds of tools in total were used, such as straw, twigs, and some kinds of leaves. The chimpanzees showed high selectivity with regard to tool type. They preferred to use Thuja occidentalis as a tool although there were 28 species of tree and several kinds of grass available in the compound. Two females initiated the use of the Thuja tool. Since then, five other individuals have begun to use it selectively. Before making the tools by themselves, these five chimpanzees first watched others using the Thuja tool for drinking juice, and then used the Thuja tool which had been used and left by another chimpanzee.  相似文献   
993.
The objective of the present study was to show that the use of adversative and conclusive connectives to mark off the prototypical schema of argumentative text begins to set in at approximately the age of 10 or 11. Based on Adam's (1992) proposals, we constituted an argumentative text with two blocks of arguments separated by an adversative instruction (the connective but or an equivalent) and followed by a conclusion introduced by a conclusive instruction (the connective thus or an equivalent). Four revising tasks (insertion or substitution with or without five connectives) have been used to asses children's knowledge of the argumentative schema and the use of connectives that punctuate them. The study of good and erroneous locations (concerning the placement of but and thus) showed that there was some regularity in the choices made by the children. The main result of this study shows that argumentative connectives are used differently by children aged 9 and children aged 10 or 11. The argumentative schema is used more consciously by 11-year-olds to guide revising tasks than by 10-year-olds.  相似文献   
994.
采用YG人格测验量表、团体智力筛选测验量表、复杂划消测验、双手调节器及深度知觉仪对港口门机事故驾驶员和非事故驾驶员所进行的研究表明:两组门机驾驶员在12项人格特征以及智力、选择反应能力上未显示出显著性差异;事故组门机驾驶员双手协调及注意分配能力和深度知觉能力明显低于非事故组门机驾驶员;技能水平与事故之间存在显著的正相关.  相似文献   
995.
The ventrolateral, agranular insular portion of prefrontal cortex (PFC) in rats is involved in visceral functions and has been shown to be involved in emotional processes. However, its contribution to aversive learning has not been well defined. Classical fear conditioning has been a powerful tool for illuminating some of the primary neural structures involved in aversive emotional learning. We measured both the acquisition and the extinction of conditioned fear following lesions of the ventrolateral PFC of rats. Lesions reduced fear reactivity to contextual stimuli associated with conditioning without affecting CS acquisition, and had no effect on response extinction. Ventrolateral PFC may normally be involved in the processing of contextual information while not being directly involved in extinction processes within the aversive domain.  相似文献   
996.
Three regular elementary teachers were trained in the use of a classroom management "skill package". Subsequently, each of these three teachers (tier 1 of training) trained three more teachers to use the same skill package (tier 2 of training). Direct behavioral measures of student disruptiveness were taken in the three tier-1 classrooms and four tier-2 classrooms, and permanent product measures of student productivity in arithmetic were taken in the three tier-1 classrooms. Results indicated that student disruptiveness decreased at least as much in the tier-2 classrooms as in the tier-1 classrooms. Data also indicated that serving as trainers benefited two of the tier-1 teachers who profited least from the original training by producing further reductions in disruptiveness in their respective classrooms. Productivity data suggested that use of the "skill package" increased classroom academic output, especially for those students below the median in productivity during baseline. The investigators' time investment in training a tier-2 teacher was one-fourth that of training a tier-1 teacher.  相似文献   
997.
Three monkeys were trained to emit a chain of three responses on three separate levers in a set of six levers to obtain food. The chain producing food (correct chain) was changed each day. During a trial, a press on any lever produced a feedback stimulus; a press on a correct lever produced an additional distinctive stimulus; the third correct press produced a food pellet. Test sessions in which either the food or the distinctive stimuli were removed were interspersed with baseline sessions. In tests without food presentations, the subjects acquired the correct chain rapidly, with a level of accuracy comparable to baseline. Removing the distintive stimuli for either the first or second member of the correct chain greatly retarded acquisition of that member of the chain. Removing all distinctive stimuli often reduced accuracy throughout the chain to chance level, even though food was presented following each correct chain. These results were interpreted as evidence that the distinctive stimuli presented after correct responses functioned as conditioned reinforcers. Reductions in accuracy following an omitted distinctive stimulus indicated that they were also discriminative stimuli for correct responding in their presence.  相似文献   
998.
Autoshaping as a function of prior food presentations   总被引:1,自引:1,他引:0       下载免费PDF全文
Young chickens were given 1, 10, 100, or 1000 presentations of grain in a hopper. Subsequently, the key was illuminated before each presentation of grain to study autoshaping of the key-peck response. The number of keylight-grain pairings before a bird first pecked the lighted key was found to be a U-shaped function of the number of prior food-only presentations, with pecks occurring significantly sooner after 100 food-only trials than after any of the other values. Two of five chicks at the 100-trial value pecked on the first illumination of the key. Experiment II showed further that when a series of food-only trials (no keylight) preceded keylight-only trials (no food) 30% of the chicks pecked the illuminated key. Experiment III extended the generality of first-trial pecking to pigeons. After preliminary training with food-only, two of five pigeons pecked on the first illumination of a key. The results suggest a close relationship between autoshaping and pseudo-conditioning.  相似文献   
999.
Pigeons were exposed to an ascending series of small fixed-ratio schedules from fixed-ratio 1 to 7. Two of those pigeons were later placed on a fixed-ratio 30 schedule. The two primary dependent variables were the postreinforcement pause and the interresponse time. Changes in these variables under small fixed ratios were sometimes opposite to changes reported with large fixed ratios. For example, postreinforcement pauses decreased in length as the fixed-ratio requirement increased from fixed-ratio 1 to fixed-ratio 3. Also, the interresponse times early in the small fixed-ratio schedule were shorter than those immediately preceding reinforcement. These findings question the role of interresponse-time reinforcement in determining temporal patterns of responding under small fixed-ratio schedules. They also suggest that there may be a limited region in which the independent variable, fixed-ratio size, does not operate as previously described.  相似文献   
1000.
Pigeons acquired a different four-response chain each session by responding sequentially on three keys in the presence of four colors. The response chain was maintained by food presentation under a fixed-ratio schedule. Errors produced a brief timeout but did not reset the chain. When either morphine or naloxone was administered alone, the overall response rate decreased with increasing doses. The rate-decreasing effect was accompanied by an increase in percent errors with morphine but not with naloxone. Both effects of morphine were antagonized by doses of naloxone that were ineffective when given alone. The antagonism was selective in that naloxone (3 mg/kg) completely blocked the error-increasing effect but not the rate-decreasing effect of the higher doses of morphine. The view that naloxone is a specific narcotic antagonist was supported by the finding that naloxone failed to antagonize the rate-decreasing and error-increasing effects of d-amphetamine, pentobarbital, and phencyclidine.  相似文献   
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