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101.
A simple extension of the DeFries and Fulker multiple regression model for twin analysis is applied to the problem of detecting linkage in a quantitative trait. The method, employing sib pairs, is based on that of Haseman and Elston. Reading data from 19 extended pedigrees were analyzed employing RLFPs as markers on chromosome 15 and using the widely available statistical applications software package, SAS. A number of possible linkages were detected, indicating that this approach is both powerful and effective, especially in the case of selected samples. Detecting genotype-environment interaction and the issue of power are briefly discussed. The programs used are available upon request.  相似文献   
102.
This study investigates the use of live supervision in counselor preparation programs. The perceived impact of live supervision on program management and student development are also considered.  相似文献   
103.
OBJECTIVE: This article was developed to identify the variables associated with abuse of children in daycare centers and homes, and to specify risk factors to guide professionals and parents. METHOD: The literature regarding child abuse (physical [PA], sexual [SA], and ritual [RA]) was reviewed, with emphasis on identification of variables associated with victims, perpetrators, and settings. Three factors increased the complexity of the review: (1) differences in definition and categorization complicated study comparison; (2) emotional tone affected some reviewers' definitions, methodology, and conclusions; and (3) some aspects of child abuse in daycare homes and centers have not been well researched. RESULTS: PA most frequently occurred in the form of over discipline, was a response to prior conflict with the child, and may have been inadvertently supported by parental permission for corporal punishment. Although SA occurred less frequently in centers than in homes, effects on the victim seemed worse in centers. SA often included PA. A Satanic overtone was frequently associated with RA, and RA coupled with SA was most devastating. Unfortunately, effects were not temporary. Males predominated the perpetrator profile. Multiple perpetrator abuse was worse (e.g., severity of intrusion). Failure of center staff to report suspicion of abuse by fellow staff or parents was cited as a worry by several researchers. CONCLUSIONS: Although research regarding abuse in daycare settings is sparse, one cannot wait for more or better research in order to identify risk factors. Based on literature reviewed, the authors provide risk factors for faculty, caregivers, parents, children, and professionals.  相似文献   
104.
This study explored infant physiologic responses of exposure to environmental tobacco smoke (ETS) using a longitudinal passive observation study with a control group. Fifteen smoking and 15 non-smoking mothers were initially contacted in hospital maternity units, with home visits made when their infants were 2, 4, and 6 weeks old. Exposure to ETS was measured using infant urinary nicotine and cotinine levels. The physiologic effects of infant ETS exposure were measured by rectal temperature, pulse rate, respiratory rate, blood pressure, and oxygen saturation. The smoking mothers in this sample were poorer, had less education, and were less likely to be married than the mothers who did not smoke. At birth, the infants of smoking mothers had higher diastolic blood pressure than infants of non-smoking mothers (p < .008). Mothers who smoke cigarettes should be educated that maternal smoking behavior can affect an infant's cardiovascular function. Parents should also be counseled about the risks of smoking in close proximity and/or in an enclosed space with an infant, especially in a motor vehicle.  相似文献   
105.
The aim of this investigation was to examine the role of social relationships in the home as predictors of social functioning in the first years of school. Longitudinal data gathered on 156 children from urban, low-income families were used to examine the unique contributions of mother-child attachment classification at ages 1 and 2 years, the child's relationship with another adult caregiver, the child's closeness to a sibling, and the child's status in the family relative to siblings between ages 3 and 4 years, to teacher reports of their own relationship to the child and the child's social skills in the classroom and peer relations. The role of family-based relationships as possible protective factors for children at social or demographic risk for problems in school was also tested. Results indicate that quality of different family relationships provides relatively independent and complementary information about early social functioning in school, with more limited evidence for compensatory or protective processes at work.  相似文献   
106.
The general nature of constructivist educators' views of teaching are overviewed first, followed by analysis of good strategy instruction in constructivist terms. That good strategy instruction is scaffolded teaching is particularly emphasized. Scaffolded teacher-student interactions necessitate that students experience unique instruction that stimulates a great deal of student construction of to-be-acquired competencies. The only important difference between good strategy teaching and teaching recommended by constructivist educators is in the explicitness of instruction, with relatively greater teacher input about what is to be learned during good strategy instruction.  相似文献   
107.
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   
108.
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   
109.
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   
110.
The authors of this paper are engaged in designing and developing telematic learning environments to assist in programmes of initial teacher training. Two aspects have been supported by European Union (EU) funded programmes: the Telematics for Teacher Training (T3) and Reflect projects. Telematics is a term describing the combined use of information technology and telecommunications. The authors are not searching for a pedagogy of telematics but are seeking ways in which telematics can assist pedagogy. Their work specifically addresses the question of whether it is possible to design such environments in a social constructivist paradigm and the evaluation of their work regularly returns to the theoretical model of learning central to their training programmes. The authors will show that whereas the aspect of video-conferencing keeps faith with their view of the nature of learning, the design of the website is raising some issues that have, as yet, to be resolved  相似文献   
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