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961.
A task involving simple mathematics, yet complex in its call for the generation of multiple solution methods, was administered to about 150 U.S. students, most of whom were in fourth grade. Written responses were examined for correctness, evidence of strategy use and mode of explanation. Results for the U.S. sample were also compared to those obtained from about 200 Japanese fourth-grade students. Students in both countries (a) produced multiple solutions and explanations of their solutions, (b) exhibited almost identical patterns and frequency of strategy use across response occasions, and (c) used the same kinds of explanations, with a majority of the responses involving solution explanations that combined both visual and verbal/symbolic features. Nevertheless, Japanese students tended to produce explanations involving more sophisticated mathematical ideas (multiplication rather than addition) and formalisms (mathematical expressions rather than verbal explanations) than did U.S. students.  相似文献   
962.
The way by which ancient Greek philosophers came to the concept of atom is presented. The concept of atom, a great creation of the human mind, gave a direct, modern-like explanation of the world, at times in which the huge amount of experimental and theoretical information of today was not available. This lack proved not an impossible obstacle for ancient Greek atomistic philosophers. The continuous regeneration, which makes Nature seem eternal, the physiology of nourishment, the orderly growth and decay of humans, animals and plants, the spreading of a sent, the evaporation and condensation of water, the wearing out of a pavement by the steps of passers-by etc., led philosophers to the concept of atoms. Similar experiences can be appealed to in teaching the concept today. Nevertheless, the concept of atom was not conceived in the same way in all ancient philosophical schools. The struggle to understand Nature, brought forth brilliant ideas and intuitions, which are directly connected to modern aspects of atomic theory, like the atomicity of time and the symmetries of the world of elementary particles. Teachers today can, with benefit to their students, retrace the ancient steps to atomic theory.  相似文献   
963.
The reputation disparity between teaching and research has stirred up an unending debate. The age-long notion that teaching and research overlap has become a controversial issue in academia. Consequences of the institutionalization of Publish OR Perish (POP) abound in the literature. This paper investigates the reputations disparity between teaching and research productivity and the rewards for these academic activities. It explores which, out of teaching activities and research publications receive higher or less attention and rewards. Relevant existing literature was reviewed to establish the institutionalization of POP and its consequences of the reputations disparity between teaching and research and its adverse effects on these activities. Evidence from the literature reviewed reveals the existence of POP reputation disparity as part of its consequences. A key finding is that teaching activities are insignificant and unrewarded as research publications. Neither the effectiveness nor the number of teaching loads counts like the numbers of publications.  相似文献   
964.
965.
966.
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   
967.
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   
968.
Constructivism deconstructed   总被引:3,自引:0,他引:3  
This paper examines the doctrine of constructivism as presented by Ernst von Glasersfeld (1989). Part I attempts to elicit a clearer statement of the concepts, positions and arguments for the latter than is immediately available in the paper. Part II discusses the problem of intersubjectivity in constructivism. The general conclusions drawn from these sections is that the basic concepts and theses of constructivism are, mostly, at best very obscure, that there is very little argument involved, and that where there is it is quite unsatisfactory. Part III ventures an explanation of at least some of the weaknesses in the doctrine, this involving a brief independent treatment of some relevant epistemological questions.  相似文献   
969.
High turnover rates of early care and education teachers reduce the quality of education; unsatisfied teachers, suffering from stress or emotional exhaustion, are less equipped to promote children’s development and more likely to leave the classroom. We used data from a national survey of US early childhood educators (n?=?1129) to examine associations between teachers’ working conditions, well-being, and motivation with professional commitment and turnover intentions to move, leave, or remain. Multiple regression analyses revealed that more intrinsically motivated teachers were more likely to report intentions to move over leave, emotionally exhausted teachers were more likely to report intentions to leave, and lower teacher-reported working conditions predicted intentions to move or leave the field over staying. The results suggest that teachers’ well-being and perceived working conditions relate with their intentions to remain at their job or within the field and to their commitment to the profession.  相似文献   
970.
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