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931.
Soon after the discovery of the expansion of the universe, astronomers hoped to determine the parameters of the universe by comparing distant galaxies with nearby ones. Observing distant galaxies, however, meant observing them as they were long ago. A crucial assumption in these studies was that galaxies hardly change, in the time scale of the expansion of the universe. Beatrice Tinsley was one of the first astronomers to point out that galaxies do change. Here we discuss a simplified model of galactic evolution, and show that the comparison of its prediction with observations uncovers clues to how galaxies evolve with time  相似文献   
932.
933.
Self- and collective efficacy beliefs were examined as correlates of attitudes toward school of teachers, school staff, and parents. 726 teachers, 387 staff members, and 1994 parents from 18 junior high schools in Milan and Rome, Italy, were administered questionnaires assessing self-efficacy beliefs, perceptions about colleagues’ bahavior, collective efficacy beliefs, affective commitment and job satisfaction of teachers and school staff and parents satisfaction with school. Path analyses corroborated a conceptual model in which self- and collective efficacy beliefs represent, respectively, the distal and proximal determinants of affective commitment and job satisfaction for teachers and staff and of satisfaction with school for parents. Perceptions that teachers, staff and parents hold about the behavior of their colleagues largely mediated the links between self- and collective efficacy beliefs. collective efficacy beliefs, in turn, largely mediated the influence that self-efficacy beliefs and perceptions of school constituencies’ behaviors exert on attitudes toward school of teachers, staff and parents.  相似文献   
934.
935.
This aim of this research was to investigate art teacher education in Taiwan and England to gain insights into two art education systems with a view to improving art teacher education in Taiwan. To achieve this aim, a cross‐cultural study using a multi‐method approach was adopted and data was collected over three years of full‐time study in England and four academic years of reflection on teaching in art teacher education in Taiwan. This research revealed how complex and hazardous it is to state categorically what the similarities and differences really are between two art teacher education systems, especially in a subject as ill‐defined as art. Nonetheless, this study did produce some important differences in the two art teacher education systems in aspects of (1) government regulations and institutional provision, (2) theoretical underpinning, (3) art curriculum policy and delivery, and (4) cultural differences affecting art teachers' attitudes and values.  相似文献   
936.
Ciliary neurotrophic factor (CNTF) has pleiotropic actions on many neuronal populations as well as on glia. Signal transduction by CNTF requires that it bind first to CNTF-R, permitting the recruitment of gp130 and LIF-R, forming a tripartite receptor complex. Cells that only express gp130 and LIF-R, but not CNTF-R are refractory to stimulation by CNTF. On many target cells CNTF only acts in the presence of its specific agonistic soluble receptors. We engineered a soluble fusion protein by linking the COOH-terminus of sCNTF-R to the NH2-terminus of CNTF. Recombinant CNTF/sCNTF-R fusion protein (Hyper-CNTF) was successfully expressed in COS-7 cells. The apparent molecular mass of the Hyper-CNTF protein was estimated from western blots to be 75 kDa. Proliferation assays of transfected BAF/3 cells in response to CNTF and Hyper-CNTF were used to verify the activity of the cytokines. The proliferative results confirmed that CNTF required homodimerization of the gp130, CNTF-R and LIF-R receptor subunit whereas Hyper-CNTF required heterodimerization of the gp130 and LIF-R receptor subunit. We concluded that the fusion protein Hyper-CNTF had superagonistic activity on target cells expressing gp130 and LIF-R, but lacking membrane-bound CNTF-R. Project supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholar, Zhejiang Province, China and SFB415, TP B5, Germany.  相似文献   
937.
An interactive videodisc system designed to teach language concepts to deaf students was evaluated in a classroom trial. An experimental group of 18 students spent 60 twenty‐minute sessions over a five‐month period learning language concepts by interacting with the system while a control group of 16 students learned the same concepts in their regular classroom setting. Both groups made significant progress from pre‐ to post‐test on two criterion‐referenced testsdeveloped by project staff. Experimental students were enthusiastic about the videodisc, felt that their language skills had improved, and were anxious to continue working with the system.  相似文献   
938.
惠民魏氏家族原籍河北枣强 ,明初迁至山东棣州。清中叶长支因出仕一度兴盛 ,四支因经商建立庞大家业 ,至七世魏毓柄时达到极盛。十世魏肇庆一度保持了发展 ,死后魏氏家族即由盛转衰。  相似文献   
939.
New instructional technologies have been increasingly incorporated into the medical school learning environment, including lecture video recordings as a substitute for live lecture attendance. The literature presents varying conclusions regarding how this alternative experience impacts students' academic success. Previously, a multi‐year study of the first‐year medical histology component at the University of Michigan found that live lecture attendance was positively correlated with learning success, while lecture video use was negatively correlated. Here, three cohorts of first‐year medical students (N = 439 respondents, 86.6% response rate) were surveyed in greater detail regarding lecture attendance and video usage, focusing on study behaviors that may influence histology learning outcomes. Students who reported always attending lectures or viewing lecture videos had higher average histology scores than students who employed an inconsistent strategy (i.e., mixing live attendance and video lectures). Several behaviors were negatively associated with histology performance. Students who engaged in “non‐lecture activities” (e.g., social media use), students who reported being interrupted while watching the lecture video, or feeling sleepy/losing focus had lower scores than their counterparts not engaging in these behaviors. This study suggests that interruptions and distractions during medical learning activities—whether live or recorded—can have an important impact on learning outcomes. Anat Sci Educ 11: 366–376. © 2017 American Association of Anatomists.  相似文献   
940.
In educational practice, test results are used for several purposes. However, validity research is especially focused on the validity of summative assessment. This article aimed to provide a general framework for validating formative assessment. The authors applied the argument‐based approach to validation to the context of formative assessment. This resulted in a proposed interpretation and use argument consisting of a score interpretation and a score use. The former involves inferences linking specific task performance to an interpretation of a student's general performance. The latter involves inferences regarding decisions about actions and educational consequences. The validity argument should focus on critical claims regarding score interpretation and score use, since both are critical to the effectiveness of formative assessment. The proposed framework is illustrated by an operational example including a presentation of evidence that can be collected on the basis of the framework.  相似文献   
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