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991.
With a relatively complex maze, reliable forgetting is clearly seen when the training-test interval is 25 days. This forgetting is evidenced by the longer time taken to run the maze and in an increase in the number of errors from the last training trial to the first test trial. In this case, forgetting is a lapse, not a loss, since performance attains the last training trial level at a subsequent test. Furthermore, a reminder which does not in itself contain sufficient information to facilitate performance of a naive animal, significantly improves maze performance of animals which have “forgotten,” even on the first retention test. With the use of additional control groups, it is shown that there must be a memory lapse before contextual cues can be demonstrated to be effective in facilitating memory retrieval.  相似文献   
992.
Socially reared juvenile bonnet macaques responded at high sustained levels in an operant task for presentation of color videotaped television images of social stimuli. Absolute levels of response depended upon the nature of the stimulus. In two experiments, subjects responded at 60.8% and 74.6% of the 1-h experimental sessions for presentation of a color videotape of a conspecific adult female moving freely in an enclosed stimulus chamber. In a later experiment, subjects maintained high levels of response during 15-min sessions for presentations of the conspecific image, but responded with significantly shorter duration responses for similar presentation of a videotape of an adult female of another macaque species, a still picture of a conspecific adult female, and a videotape of the empty stimulus chamber. With longer, 1-h, stimulus presentation, the three social stimuli sustained high levels of response while responses for presentation of the empty stimulus chamber waned significantly over the experimental session. The sustained high levels of response obtained over several hours of stimulus presentation suggest the value of color videotape stimuli in the experimental study of social perception in nonhuman primates.  相似文献   
993.
Delayed-reward learning in pigeons was examined using a simultaneous red-green visual discrimination task in which the conditions during the delay interval were varied between groups. The nondifferential group received training in which the stimulus present during the 1-min delay was the same following a peck on the correct and incorrect colors. The other three groups received 1-min delay training in which different stimuli occurred in the delay interval following correct and incorrect choices. The differential group received continuous, differential stimuli during the delay. The reinstatement group received the differential stimuli in the 10 sec immediately following the choice and during the last 10 sec of the delay. The reversedcue group was treated in the same way, except that the 10-sec delay stimulus immediately following an incorrect response was also presented for 10 sec prior to reward on correct choices, and the stimulus following a correct response also occurred 10 sec before nonreward on incorrect choices. Nondifferential birds failed to learn the discrimination, while differential and reinstatement birds learned it readily. The reversed-cue birds learned to choose the incorrect stimulus. Differential and reinstatement birds showed no decrement in performance when the delay was increased to 2 min. These findings suggest that similarity of prereward and postresponse delay stimuli controls choice responding in long-delay learning, a finding compatible with both memorial and conditioned reinforcement interpretations.  相似文献   
994.
Prior work has shown that when the separate correct responses of a conditional discrimination are followed by different reinforcing outcomes, performance is enhanced relative to that obtained under the conventional, single-reinforcer procedure. Four experiments with pigeons yielded the analogous finding when the different outcomes were reinforcement and explicit nonreinforcement. Controls indicated that the results could not be attributed to the effects of intermittent reinforcement, to possible differences in cue duration, or to a variety of potential sources of conditioned reinforcement. An interpretation in terms of expectancy learning is proposed.  相似文献   
995.
The purpose of this study was to determine the degree of comparability between the WISC and the WISC-R over time. Hypotheses were tested using a sample of 276 mildly mentally handicapped children enrolled in special education classes who had received a WISC (Trial 1) and a WISC or WISC-R (Trial 2) after an interval of approximately three years. The sample was grouped on the basis of test administered in Trial 2. Group I contained those children who received the WISC on Trial 2 and included 183 children, of whom 121 were males and 62 were females. Mean age at time of initial testing was 8–10; mean age at second testing was 11–8. Group II was composed of 93 children who had been posttested on the WISC-R and included 72 males and 21 females. Mean age at initial testing was 9–5; mean age at posttest was 13–0. The study was conducted in five school districts and one county department of education. Verbal IQ, Performance IQ, and Full Scale IQ for both instruments administered were transcribed from the special education folders of the children. The design used to test hypotheses was repeated measures analysis of variance. Data analysis resulted in rejection of the hypotheses that the WISC-R yields mean Verbal, Performance, and Full Scale IQ scores greater than or equal to the corresponding mean IQ scores of the WISC. It was concluded that the WISC-R may unfairly penalize special education children who are reevaluated with this instrument. Fluctuations in IQ scores due to the instrument of measurement must be recognized, and appropriate action should be taken to insure that children are evaluated for special class placement on comparable bases.  相似文献   
996.
Pelgrum  Willem J. 《Prospects》1992,22(3):341-349
Since 1987, International Co-ordinator of the IEA Computers in Education Study; was national project coordinator for the IEA Second International Mathematics Study and Second International Science Study (1980–85). Co-author of several published studies on the Second International Science Study as well as The Implemented and Attained Mathematics Curriculum: A Comparison of Eighteen Countriesand The Use of Computers in Education Worldwide.  相似文献   
997.
The present study examines high school students with a prior history of grade retention (N = 38) compared to a matched control group of nonretained students. The retained students were lower on a number of scholastic variables (i.e., achievement, intelligence, grades), more often absent from school, and lower on three subscales of a self-esteem measure (the Self-Perception Profile for Adolescents). The authors explored the correlates of grade retained with the measured variables and found that the later a student was retained was associated with lower grades, less-positive school attitudes, less time on homework, lower educational expectations, more discipline problems, lower self-control, and a more external locus of control.  相似文献   
998.
When a crisis occurs in the school setting, school officials must be prepared to handle the situation effectively and efficiently. One of the ways school officials can handle a crisis situation is through the use of crisis intervention teams. The steps in establishing a crisis intervention team in a school setting include: determining goals, performing a needs assessment, finding model programs, developing a membership pool, developing a training program, preparing and maintaining a list of resources and plans for support services, establishing a communication network, designating a base of operations, planning team meetings, keeping records, and implementing the phases of debriefing. A crisis management scenario is presented and discussed in terms of the steps.  相似文献   
999.
1000.
A person-centered approach was employed to investigate how students' evaluation of perceived teacher utility value messages, i.e., fear appeals, as a threat and as a challenge, combined within individuals and how these combinations related to student engagement. Two studies were conducted with students in their final two years of secondary education. Empirically distinct clusters emerged at two time points in the academic year. Evaluating the message in the fear appeal at a higher level of challenge than threat was beneficial. Unexpectedly, high threat was associated with high engagement, as long as high challenge was also present, however, this combination was also related to high emotional disaffection. Moderate threat combined with moderate challenge had the most detrimental relationship with student engagement. Educational interventions should aim to increase the likelihood of a challenge evaluation.  相似文献   
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