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991.
Abstract Recognizing the recent dramatic increase in the number of channels available to the typical American household coinciding with an equally dramatic decrease in audience ratings for the major broadcast networks, there was reason to hypothesize that, in recent years, lead‐in or inheritance effects have diminished. However, an analysis of prime time ratings comparing 1992 with 2002 for ABC, CBS, NBC and Fox showed no support for this notion, suggesting that, despite the recent upheavals in the television industry, lead‐in has not lost its punch. 相似文献
992.
993.
The purpose of this paper is twofold: to describe robust rationales for integrating inquiry-based learning into undergraduate science education, and to propose that digital libraries are potentially powerful technological tools that can support inquiry-based learning goals in undergraduate science courses. Overviews of constructivism and situated cognition are provided with regard to how these two theoretical perspectives have influenced current science education reform movements, especially those that involve inquiry-based learning. The role that digital libraries can play in inquiry-based learning environments is discussed. Finally, the importance of alignment among critical pedagogical dimensions of an inquiry-based pedagogical framework is stressed in the paper, and an example of how this can be done is presented using earth science education as a context. 相似文献
994.
Transcribing sign communication used simultaneously with spoken English presents investigators with a unique problem: the singular quality of the bimodal communicative interactions cannot be accurately depicted using accepted conventions for recording either spoken or signed language samples. This article proposes guidelines for transcribing such data. The need for guidelines arose during an earlier study of the language development of a hearing child of deaf parents. To meet the immediate needs of that study, rules and conventions from previous studies were combined with newly generated ones, resulting in the guidelines proposed in this article. The guidelines can be applied to data in which intermodal linguistic influence is suspected. 相似文献
995.
Profiles of emergent literacy skills among preschool children who are at risk for academic difficulties 总被引:1,自引:0,他引:1
Sonia Q. Cabell Laura M. JusticeTimothy R. Konold Anita S. McGinty 《Early childhood research quarterly》2011,26(1):1
The purpose of this study was to explore patterns of within-group variability in the emergent literacy skills of preschoolers who are at risk for academic difficulties. We used the person-centered approach of cluster analysis to identify profiles of emergent literacy skills, taking into account both oral language and code-related skills. Participants were 492 preschoolers (aged 42-60 months) enrolled in needs-based programs. In the fall of the academic year, children were administered eight measures of emergent literacy: four oral language measures (i.e., expressive and receptive grammar, expressive and receptive vocabulary) and four code-related measures (i.e., print concepts, alphabet knowledge, name writing, and rhyme). Controlling for age, hierarchical-agglomerative and K-means cluster analysis procedures were employed. Five psychometrically sound profiles emerged: highest emergent literacy (prevalence = 14%); three profiles with average oral language and differential code-related abilities (16%, 24%; 23%); and lowest oral language with broad code-related weaknesses (23%). Profiles were then compared on midyear teacher ratings of emergent literacy as well as end-of-kindergarten literacy performance; results provided convergent evidence of predictive validity. This study highlights the considerable heterogeneity of emergent literacy abilities within an “at-risk” group. The resulting profiles have theoretical and practical relevance when examining both concurrent relationships between oral language and code-related skills as well as longitudinal relationships between early patterns of performance and later reading achievement. 相似文献
996.
Andrea A. diSessa Flavio S. Azevedo Orit Parnafes 《Interactive Learning Environments》2013,21(1-2):109-159
This paper provides a review of the rhetoric behind the component movement in educational software, and a critical analysis and synthesis of issues underlying the movement. We draw on case studies of several significant recent component projects in order to assess claims and to uncover and examine issues that are less often considered. While our empirical base cannot definitively answer all the questions raised, we hope to bring some clarity and some empirically based judgments to bear on how a promising technological innovation can best serve educational ends. Our study led to a focus on three critical issues: (1) the nature of the environment in which components are configured and used; (2) the extent of modifiability that is necessary for effective re-use of components; (3) how the work of designing components and component configurations is distributed among people with different competencies. 相似文献
997.
The longitudinal development of the intraindividual coupling between academic achievement, interest, and self-concept of ability (SCA) was analyzed in a sample of approximately 1,000 children between grades 1 and 12 (ages 6-17). Across all calculated indexes, the average level of coupling was positive. Individuals generally felt competent and interested in domains where they achieve well, and were interested in domains where they perceive their personal strengths. The degree of coupling was the highest between interest and SCA and the lowest between interest and achievement. For all indexes, evidence for an increase in coupling across time was found. Female gender was related to a lower level of coupling. There was evidence for a positive effect of conscientiousness on the amount of coupling. 相似文献
998.
The elusive neutrinos have periodically yielded their secrets to man and at each such juncture major advances have been achieved
in our understanding of the sub-atomic phenomena. These particles also carry invaluable information about the centre of the
Sun where energy is generated through nuclear fusion. In Part I of this article, history of the discovery of neutrinos is
traced, their properties and types are described. Also, the Standard Model which forms the basis of the structure of matter
and of which massless neutrinos are an integral part, is described. The role of neutrinos in solar energy generation and the
great ‘solar neutrino puzzle’ and its solution will be described later in the series. 相似文献
999.
The purpose of this study was to concurrently examine the development of written language across different writing tasks and
to investigate how writing features develop in preschool children. Emergent written language knowledge of 372 preschoolers
was assessed using numerous writing tasks. The findings from this study indicate that children demonstrate knowledge about
writing before beginning school and receiving formal instruction. There was clear evidence to support the claim that universal
writing features develop before language-specific features. Children as young as 3 years possess knowledge regarding universal
and language-specific writing features. Preschoolers appear to progress along a continuum from scribbling to conventional
spelling. Although this progression is sequential, children’s writing proficiency is task dependent. Implications of these
findings on writing development are discussed. 相似文献
1000.
The experiments reported in the present study tested whether decreasing intertrial intervals (ITIs) intensifies the disruptive
effects of increasing retention intervals (RIs) in a delayed conditional discrimination by decreasing the animal’s trial tracking
accuracy (Cohen & Armstrong, 1996; Cohen & Roberts, 1996). Rats responded on a fixed ratio (FR) 1 or fixed interval (FI) 10-sec
reinforcement schedule at a second light or tone stimulus, S2, when the first light or tone stimulus, S1, had signaled an
FI 10-sec or FR 1 schedule, respectively. RIs between S1 and S2 were increased from 3 to 24 sec and never exceeded ITIs that
were reduced from 24 to 6 sec. For some rats, the trials were separated from each other by extending the lever at S1 and retracting
it at the end of S2 (ITI lever-retracted group). For other, control rats, the lever remained extended throughout the session
(lever-extended group, Experiment 1) or was extended and retracted with the onset and offset of each stimulus (RI/ITI lever-retracted
group, Experiment 2). The rats under all trial conditions learned to delay leverpressing on the FI 10-sec schedule. Latency
to begin leverpressing on the FI 10-sec schedule declined as RIs were increased, but this effect was attenuated in the ITI
lever-retracted groups in both experiments, as would be predicted by thetrial tracking hypothesis. Decreasing ITIs from 24 to 6 sec intensified the disruptive effects of increasing RIs from 3 to 6 sec in the
RI/ITI lever-retracted group (Experiment 2), as would be predicted by the trial tracking hypothesis. 相似文献