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201.
Obesity rates among preschool-aged children have doubled in the past 10 years, and 60 % of these children spend the majority of their day in childcare facilities. Few studies have examined the quality of nutrition and physical activity practices in childcare centers as compared to family childcare homes. The purpose of this study is to determine if a pattern of differences exist in these two settings. As part of a CDC-funded study to reduce the obesity epidemic in young children, directors of 1,140 childcare facilities (842 out-of-home and 298 in-home) in one large county completed a survey that detailed their practices related to child nutrition and physical activity. Results showed that compared with out-of-home facilities, in-home facilities were more likely to report excellent indoor physical activity (87.2 vs. 85.5 %, p = 0.059), less likely to report excellent outdoor physical activity (92.8 vs. 96.5 %, p = 0.018), more likely to serve fruit (80.3 vs. 51.2 %), and less likely to serve 1 % milk (45.2 vs. 55 %). This study’s present findings revealed that ample opportunity exists to significantly improve the health of young children in both in-home and out-of-home facilities.  相似文献   
202.
Instructional design (ID) models have been developed to promote understandings of ID reality and guide ID performance. As the number and diversity of ID practices grows, implicit doubts regarding the reliability, validity, and usefulness of ID models suggest the need for methodological guidance that would help to generate ID models that are relevant and appropriate to the ever-changing design challenges in our world. Because the construction of an ID model involves an intricate externalization of unique sets of design experiences as well as a logical synthesis of relevant research, the purpose of this study was to formulate a methodological framework for ID model development. Through the analysis of 20 selected studies, four critical dimensions and ten synthesized procedures for constructing ID models were formulated. The resulting framework is intended to provide a useful theoretical and practical contribution to the field of ID.  相似文献   
203.
204.
How do students draw on texts read in class to explore and make sense of the world? How does role-play open up the possibilities of utilising these resources, remaking them for their own purposes? How does play, as Vygotsky suggests, enable students to achieve more? And how does being in role change the character of social relations in the classroom, enabling students to shed new light on their lives, their experiences. This essay focuses close attention on two role-plays, both involving the same pair of 11th-grade students from a school in Ramallah. The role-plays arose out of, and enabled the students to explore, literary texts that they had been studying in class: Ibsen’s A Doll’s House and Steinbeck’s Of Mice and Men. The article argues that what the students accomplished in this work is complex and needs to be understood in context. Through this account, the essay seeks to challenge those (currently fashionable) models of pedagogy that are insufficiently attentive to the histories, identities and interests of particular learners.  相似文献   
205.

In two dimensions (2D), representations associated with slopes are seen in numerous forms before representations associated with derivatives are presented. These include the slope between two points and the constant slope of a linear function of a single variable. In almost all multivariable calculus textbooks, however, the first discussion of slopes in three dimensions (3D) is seen with the introduction of partial derivatives. The nature of the discussions indicates that authors seem to assume that students are able to naturally extend the concept of a 2D slope to 3D and correspondingly it is not necessary to explicitly present slopes in 3D. This article presents results comparing students that do not explicitly discuss slopes in 3D with students that explicitly discuss slopes in 3D as a precursor to discussing derivatives in 3D. The results indicate that students may, in fact, have significant difficulty extending the concept of a 2D slope to a 3D slope. And that the explicit presentation of slopes in 3D as a precursor to the presentation of derivatives in 3D may significantly improve student comprehension of topics of differentiation in multivariable calculus.

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206.
This study examines key school reform policies and outcomes of the USA and Korea over the past three decades from comparative perspectives. Since the two nations’ unique educational problems brought divergent educational reform paths—standardization versus differentiation, high-stakes testing versus individualized assessment, and centralization versus decentralization—the study tracks international policy benchmarking efforts and potential impact on educational convergence. The study employs mixed methods, including the content analysis of research and media documents and the trend analysis of TIMSS and PISA datasets. The results indicate that, despite significant changes in policy discourse, the gaps between Korea and the USA in student math achievement and school climates did not narrow. The policy lessons from these cases and the issues of international education benchmarking are discussed.  相似文献   
207.
Embryology is integrated into the Clinically Oriented Anatomy course at the Texas Tech University Health Sciences Center School of Medicine. Before 2008, the same instructor presented embryology in 13 face‐to‐face lectures distributed by organ systems throughout the course. For the 2008 and 2009 offerings of the course, a hybrid embryology instruction model with four face‐to‐face classes that supplemented online recorded lectures was used. One instructor delivered the lectures face‐to‐face in 2007 and by online videos in 2008–2009, while a second instructor provided the supplemental face‐to‐face classes in 2008–2009. The same embryology learning objectives and selected examination questions were used for each of the three years. This allowed direct comparison of learning outcomes, as measured by examination performance, for students receiving only face‐to‐face embryology instruction versus the hybrid approach. Comparison of the face‐to‐face lectures to the hybrid approach showed no difference in overall class performance on embryology questions that were used all three years. Moreover, there was no differential effect of the delivery method on the examination scores for bottom quartile students. Students completed an end‐of‐course survey to assess their opinions. They rated the two forms of delivery similarly on a six‐point Likert scale and reported that face‐to‐face lectures have the advantage of allowing them to interact with the instructor, whereas online lectures could be paused, replayed, and viewed at any time. These experiences suggest the need for well‐designed prospective studies to determine whether online lectures can be used to enhance the efficacy of embryology instruction. Anat Sci Educ 7: 234–241. © 2013 American Association of Anatomists.  相似文献   
208.
State and Local governments must develop an overarching legal foundation to manage critical service delivery in an electronic environment. Prior to establishing a foundation, decision-makers must first adopt a philosophy that focuses and harnesses expressions of law and public policy. The research and development community must supports the nation’s efforts with programs designed to aid in the risk assessment process. These programs must focus on identifying better ways to quantify risk, understanding infrastructure interdependency, and measuring cascading damages flowing from service outages. Finally, State and Local leaders should adopt security guidelines for industry and government service providers. Guidelines involve ten well-defined process requirements, all of which must be implemented to provide services online and in a safe and secure manner.  相似文献   
209.
The oil painting “La Medusa” executed by Caravaggio at the end of the XVI century on a wooden shield, was investigated by integrated physical–chemical and analytical methodologies in order to obtain scientific data capable of elucidating the state of conservation and the painting technique. Optical (OM) and electronic (SEM-EDS) microscopy, micro-FT-IR spectroscopy, gas chromatography–mass spectrometry (GC–MS) and pyrolysis GC–MS were applied on two microfragments and some organic samples obtained by solvent extraction using the swab cleaning technique. The obtained results indicated that Caravaggio probably reused an old shield as a previous gypsum preparation layer has been detected under the original painting layers. He used white lead, natural earths, verdigris and lead–tin yellow type I mixed with drying oils to paint. The considerable amount of amorphous particles of copper chlorides found in the green pigment verdigris suggests that it could have been produced according to the ancient recipe of verde salsum described by Theophilus. Mordant gilding has been identified on the upper part of the shield that can be related to an abandoned experiment to give the painting a mirror-like reflecting effect. Three different varnishes layers have been detected above the painted surface. The original and restoration varnishes have been identified and they contain a mixture of drying oil, mastic and turpentine and some beeswax. Cleaning tests, performed with different organic solvents, suggest the use of isopropyl alcohol as cleaning agent because it is less efficient in comparison to others solvents; thus it ensures a careful and controlled removal of the varnishes.  相似文献   
210.
Stereotype research depicts the generic immigrant as incompetent and untrustworthy. The current research expands this image, specifying key information dimensions (e.g. nationality, socioeconomic status) about immigrants. To see how perceivers differentiate among particular immigrant groups, we extend a model of intergroup perception, the Stereotype Content Model (SCM; Fiske, Cuddy, Glick, & Xu, 2002. Journal of Personality and Social Psychology, 82, 878–902), to immigrant subgroups. The SCM predicts that perception centers on competence and warmth, and relates to targets’ perceived status and competition within society. Specified by nationality, race, ethnicity, and class, images of immigrants differ by both competence and warmth, with most groups receiving ambivalent (low–high or high–low) stereotypes rather than the uniform low–low for the generic immigrant. As predicted, ambivalent stereotypes reflect target nationality combined with socioeconomic status, supporting the SCM's ambivalent stereotypes and social structural hypotheses, as well as better defining immigrant stereotypes and their contingencies.  相似文献   
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