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991.
Even though several studies have reported positive attitudinal outcomes from context-based chemistry programs, methodological obstacles have prevented researchers from comparing satisfactorily the chemistry-learning outcomes between students who experience a context-based program with those who experience a content-driven program. In this narrative inquiry we are able to address the question: how do the recalled experiences of a student and her teacher in context-based and concept-based chemistry programs compare? From the student’s unique perspective of experiencing both programs with the same teacher, we have constructed our collective account around four themes; namely, the extent to which the student makes connections between chemistry concepts and real-world contexts, developing research independence through engaging in extended experimental investigations related to contexts, learning chemistry concepts through contexts, and conceptual sequencing in a context-based program. The student reported real-world connections between chemistry concepts and contexts, found her engagement in the context-driven tasks interesting and productive, and identified connected sequences of concepts across the contexts studied. Despite difficulties for teachers who are required to shift pedagogies, the student’s lived experiences and outcomes from a context-based program provide some encouragement in working through these issues.  相似文献   
992.
The increasing importance of constructivism in higher education has brought about a shift in pedagogy from a focus on the teacher to a focus on the student. This has important implications for teaching and assessment. A student-centred pedagogy implies a different role for the teacher. What exactly does student-centred teaching require from teachers’ actual teaching practice? What is expected from them in order to teach in a student-centred way? It is in order to respond to these questions that this research project has been carried out establishing a core competence profile of student-centred teachers in higher education. Qualitative data were collected by means of semi-structured in-depth interviews with teachers from different institutions for higher education in Belgium, known for their student-centred way of teaching. This research method is innovative compared to the methods used for existing competence lists in the literature, which were usually developed on the basis of conversations with pedagogical experts. By exploring practice and having teachers participate in the development of a competence list, the acceptance of a competence profile is much higher. The result of the project is a validated competence profile which takes into account the critiques on existing competence lists. The competence profile provides a further insight in the functioning of teachers within a student-centred pedagogy and can be used as a starting point for the educational development of teachers within this pedagogy.  相似文献   
993.
This article investigates the intertwined constructs of metacognition and self-regulation as they emerge in the works and theories of James, Piaget, and Vygotsky. To coordinate this exploration, we use an interpretive framework based on the relation of subject and object. In this framework, James’s perspective on metacognition and self-regulation is aligned with the Self, Piaget’s with the other and object, and Vygotsky’s with the medium or agency of language. We explore how metacognition and self-regulation function within the realm of human behavior and development as described in the works of each of these theorists. Key questions or issues that emerge for current research are outlined, and the limitations and benefits of each theorist’s perspective vis-à-vis metacognition and self-regulation are discussed.  相似文献   
994.
The purpose of this study was to describe and understand the range of outcomes of class visits to natural history museums. The theoretical framework is based on the multifaceted process of learning in free choice learning environments, and emphasizes the unique and individual learning experience in museum settings. The study’s significance is in highlighting several possible cognitive as well as non-cognitive learning effects in museums class visits, by providing the student’s point of view. Data was collected by semi-structured interviews with 50 students in grades 6–8 on the day following the visit. We present evidence that students expressed several learning outcomes, connected directly and indirectly to the scientific content of the visit. Content oriented outcomes included acquiring scientific knowledge and making connections to prior knowledge; social oriented outcomes were identified in students’ statements regarding communicating knowledge and social aspects of learning; and interest oriented outcomes were evidenced by students’ expressions about emotions, interest and curiosity. The aggregate data addressed the common outcomes and the impact of class visits to natural history museums in the short term. Comparisons between two types of museums show significant differences in several aspects, regarding the exhibit and/or the activity type. Practical ideas for structuring the ultimate experience are included.  相似文献   
995.
One of the great strengths of Jim Kaput’s research program was his relentless drive towards scaling up his innovative approach to teaching the mathematics of change and variation. The SimCalc mission, “democratizing access to the mathematics of change,” was enacted by deliberate efforts to reach an increasing number of teachers and students each year. Further, Kaput asked: What can we learn from research at the next level of scale (e.g., beyond a few classrooms at a time) that we cannot learn from other sources? In this article, we develop an argument that scaling up research can contribute important new knowledge by focusing researchers’ attention on the robustness of an innovation when used by varied students, teachers, classrooms, schools, and regions. The concept of robustness requires additional discipline both in the design process and in the conduct of valid research. By examining a progression of three studies in the Scaling Up SimCalc program, we articulate how scaling up research can contribute to designing for and evaluating robustness.  相似文献   
996.
This article is situated in the research domain that investigates what mathematical knowledge is useful for, and usable in, mathematics teaching. Specifically, the article contributes to the issue of understanding and describing what knowledge about proof is likely to be important for teachers to have as they engage students in the activity of proving. We explain that existing research informs the knowledge about the logico-linguistic aspects of proof that teachers might need, and we argue that this knowledge should be complemented by what we call knowledge of situations for proving. This form of knowledge is essential as teachers mobilize proving opportunities for their students in mathematics classrooms. We identify two sub-components of the knowledge of situations for proving: knowledge of different kinds of proving tasks and knowledge of the relationship between proving tasks and proving activity. In order to promote understanding of the former type of knowledge, we develop and illustrate a classification of proving tasks based on two mathematical criteria: (1) the number of cases involved in a task (a single case, multiple but finitely many cases, or infinitely many cases), and (2) the purpose of the task (to verify or to refute statements). In order to promote understanding of the latter type of knowledge, we develop a framework for the relationship between different proving tasks and anticipated proving activity when these tasks are implemented in classrooms, and we exemplify the components of the framework using data from third grade. We also discuss possible directions for future research into teachers’ knowledge about proof.
Andreas J. StylianidesEmail:
  相似文献   
997.
In two experiments using a radial-arm maze, pairs of rats made choices among eight maze locations, each containing a large quantity of one of two food types. The choices made by 1 rat affected the choices made by the other rat. Under most conditions, visits by 1 rat increased the tendency of the other rat to subsequently choose that maze location. However, the effect depended on the quality of the food available in a particular location. When it was possible for the rats to observe each other on the maze arms and a rat had experienced that a location contained the less preferred food type, a previous visit to that location by the foraging partner decreased the tendency to visit that location. These effects are attributed to working memory for the spatial choices of another rat, and they indicate that memory produced by a rat’s own visit to a maze location is integrated with memory for the behavior of another rat to determine spatial choice  相似文献   
998.
This paper presents a novel mega-Hz-level super high frequency zero-voltage soft-switching converter for induction heating power supplies. The prominent advantage of this topology is that it can absorb both inductive and capacitive parasitic components in the converter. The switch devices operate in a zero-voltage soft-switching mode. Consequently, the high voltage and high current spikes caused by parasitic inductors or capacitors oscillation do not occur in this circuit, and the high power loss caused by high frequency switching can be greatly reduced. A large value inductor is adopted between the input capacitor and the switches, thus, this novel converter shares the benefits of both voltage-type and current-type circuits simultaneously, and there are no needs of dead time between two switches. The working principles in different modes are introduced. Results of simulation and experiments operated at around 1 MHz frequency verify the validity of parasitic components absorption and show that this convener is competent for super high frequency applications.  相似文献   
999.
This paper studies the social talk of high school students in online discussion forums. On-task talk has generally been assessed as valuable discussion because it contributes directly to productive learning. Off-task conversation, on the other hand, is often regarded as useless and a waste of time. Should this social talk indeed be regarded as an off-task activity? Is social talk such as greeting, excusing, comforting and sharing personal feelings irrelevant to learning? This study analyzes threads and argues that social talk is interwoven with on-task talk. It is interesting to note that a substantial quantity of off-task messages served the latent function of guiding group discussion toward making progress in solving collaborative problems in a subtle and indirect manner. The power of “soft talk” embedded in off-task social conversation is explored and fully discussed.  相似文献   
1000.
In Iran, restructuring of medical education and the health care delivery system in 1985 resulted in a rapid shift from elite to mass education, ultimately leading to an increase in the number of medical schools, faculties, and programs and as well as some complications. This study aimed to investigate views on academic culture, values, and routines held by faculty members. A nation-wide survey conducted in six public medical schools in Iran. The research findings show weak organizational culture and values, together with routine behaviors sensed as a negative and low satisfaction with academic leadership. The research evidence suggests bureaucracy, politicization, conservativeness, and centralization as common features of medical schools in Iran and also suggests suitable supervisory skills to tackle the tension between governmental management and academic leadership with cultural changes, the creation of new values, and adoption more efficient routines.  相似文献   
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