全文获取类型
收费全文 | 9623篇 |
免费 | 118篇 |
国内免费 | 6篇 |
专业分类
教育 | 6479篇 |
科学研究 | 1132篇 |
各国文化 | 326篇 |
体育 | 724篇 |
综合类 | 5篇 |
文化理论 | 67篇 |
信息传播 | 1014篇 |
出版年
2022年 | 72篇 |
2021年 | 110篇 |
2020年 | 140篇 |
2019年 | 203篇 |
2018年 | 244篇 |
2017年 | 267篇 |
2016年 | 235篇 |
2015年 | 162篇 |
2014年 | 192篇 |
2013年 | 1666篇 |
2012年 | 209篇 |
2011年 | 201篇 |
2010年 | 189篇 |
2009年 | 184篇 |
2008年 | 237篇 |
2007年 | 216篇 |
2006年 | 182篇 |
2005年 | 173篇 |
2004年 | 182篇 |
2003年 | 128篇 |
2002年 | 116篇 |
2001年 | 154篇 |
2000年 | 182篇 |
1999年 | 158篇 |
1998年 | 90篇 |
1997年 | 84篇 |
1996年 | 75篇 |
1993年 | 86篇 |
1992年 | 138篇 |
1991年 | 149篇 |
1990年 | 149篇 |
1989年 | 157篇 |
1988年 | 120篇 |
1987年 | 118篇 |
1986年 | 117篇 |
1985年 | 156篇 |
1984年 | 127篇 |
1983年 | 119篇 |
1982年 | 99篇 |
1981年 | 85篇 |
1980年 | 94篇 |
1979年 | 145篇 |
1978年 | 89篇 |
1977年 | 91篇 |
1976年 | 79篇 |
1975年 | 76篇 |
1974年 | 88篇 |
1973年 | 80篇 |
1971年 | 74篇 |
1968年 | 74篇 |
排序方式: 共有9747条查询结果,搜索用时 15 毫秒
141.
If freezing underlies barpress conditioned suppression, then it seems odd that auditory cues paired with shock evoke more freezing than do visual cues, yet evoke similar suppression. Bevins and Ayres (1992) found that auditory and visual cues also evoked similar withdrawal from the bar and dipper areas and suggested that such withdrawal could explain the similar suppression. Seeking to understand that withdrawal, we found evidence in the present study that it was due either to adventitious punishment or to place-aversion learning. The cue for shock seemed to set the occasion for such learning. For example, we found that, as training progressed, rats’ tendency to leave the bar area during the cue first increased, then decreased, then increased again, reflecting, presumably, shock occurrence first inside, then outside, then inside the bar area again. Despite these changes in the rats’ location, barpress suppression remained stable, implying that leaving the bar area, though sufficient for barpress suppression, is unnecessary. 相似文献
142.
Higher education in the United States and elsewhere is beset by crises: crises of public confidence, questions of continuing relevance, doubts about continuing the emphasis on doctoral instruction, and a very real financial crisis. In response, governing boards and governmental agencies are devoting increasing attention to the management of higher education. Part of this response has been a heightened interest in formal planning-programming-budgeting-systems (PPBS); in fact, several states have legislated the adoption of PPBS for higher educational planning and decision making. Similar interest has been evidenced in other countries. Therefore, it is an appropriate time to reconsider the nature and role of PPBS and its potential impact on higher education. This paper describes the salient characteristics of PPBS and traces the development of PPBS and related analytical techniques in governmental agencies and institutions of higher education. A second paper will illustrate both the concepts and the implementation of PPBS by a detailed exposition of the University of California's experience with PPBS. Finally, in a third paper we suggest an alternative view of policy analysis for educational planning which is a departure from traditional PPBS. We conclude with general observations and specific recommendations to educational managers seeking to improve their resource allocation procedures. 相似文献
143.
144.
Arzu Saka Lale Cerrah Ali Rıza Akdeniz Alipaşa Ayas 《Journal of Science Education and Technology》2006,15(2):192-202
The study was carried out with 175 Turkish students by using drawings at different ages understanding of gene, DNA and chromosome concepts. Students from 8th, 9th, 11th grades and, science and biology student teachers were simply asked to draw the structure of gene, DNA and chromosome in a cell and also to give explanations about these three concepts. Differences in understanding between the age groups were found to be significant for the concepts of gene and DNA. None of the groups exhibit sound understanding and regardless of the age levels, students in all groups had alternative ideas about the three concepts investigated. 相似文献
145.
Neil B. Marks and Richard T. O'Connell 《Decision Sciences Journal of Innovative Education》2003,1(2):259-272
In this paper, a method for analyzing data from student evaluations of teaching is presented. The first step of the process requires development of a regression model for teacher's summary rating as a function of student's expected grade. Then, two‐sigma control charts for individual evaluation scores (section averages) and residuals from the regression model are used to identify both excellent and poor outcomes. The performance of an individual whose scores are out of control on both charts cannot be explained by expected grade and therefore is worthy of note. 相似文献
146.
The retention and extinction of a visual discrimination was examined in BALB/c mice. The mice were trained to perform a go/no-go discrimination task in parallel runways. Initial training resulted in an intermediate level of performance. Testing consisted of an additional session using either retention (Experiment 1) or extinction (Experiment 2) at one of five time intervals between 1 and 30 days. It was found in Experiment 1 that forgetting progressively increased over intervals of between 14 and 30 days. In Experiment 2, extinction testing induced more impairment of performance, so that forgetting occurred earlier relative to retention testing in Experiment 1. However, in both experiments, the measure of performance by a discrimination ratio revealed the same amount of forgetting when the training-test interval was 30 days. These results define the forgetting curve for such a discrimination by mice. They are discussed in terms of possible factors involved in forgetting. 相似文献
147.
Rats were trained to leverpress for food and subsequently exposed to either arithmetic series or random variable-interval reinforcement schedules. Adjunctive drinking developed in all subjects exposed to arithmetic variable-interval reinforcement, but did not develop in six of the eight animals trained on the random schedule. The results suggest that adjunctive drinking is the result of an interaction between the tendency of rats to drink after eating and the ability of locally low probabilities of reinforcement within schedules to induce conditioned behavioral states. 相似文献
148.
In order to emphasize the development of skills in helping the culturally disadvantaged, graduate students were given practicum placement in a Department of Labor-financed agency which gave counseling and employment training to disadvantaged youth. Students attended staff meetings, interviewed staff members concerning the work they performed, and discussed client contacts with caseworkers, in addition to interviewing agency clients. Increased awareness of problems, broadened conceptualizations, and expansion of interpersonal skills were seen as advantages of the practicum. Limitations included some lack of goal clarity and inefficiency of time use in dealing with this clientele. 相似文献
149.
150.
To explain students' achievement in the mechanics segment of a college physics course, a causal model is proposed whose variables are the three constructs: Newtonian physics, math ability, and science experience. Each variable specifies several variates, whose numerical values were measured and intercorrelations computed. The Factorial Modeling (FaM) procedure is applied to the data to estimate the coefficients of the proposed model's structural equations. The FaM results indicate that the model is plausible and that its first two variables account for approximately 34% of the variance in the criterion variate, students' mechanics achievement. The implications of the findings for physics instruction are discussed. 相似文献