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481.

Objective

The aim of the current study was to evaluate the effect of ultraviolet (UV) photofunctionalization of dental titanium implants with exposure to the oral cavity on osseointegration in an animal model.

Methods

Forty-eight titanium implants (Camlog® Conelog® 4.3 mmx9.0 mm) were placed epicrestally into the edentulous jaws of three minipigs and implant stability was assessed by measuring the implant stability quotient (ISQ). Prior to implantation half of the implants were photofunctionalized with intense UV-light. After three months, the implants were exposed and ISQ was measured again. After six months of implant exposure, the minipigs were sacrificed and the harvested specimens were analyzed using histomorphometric, light, and fluorescence microscopy.

Main results

Forty-two of 48 implants osseointegrated. The overall mean bone-implant contact area (BIC) was (64±22)%. No significant differences were found in BIC or ISQ value (multivariate analysis of variance (MANOVA), P>0.05) between implants with and without exposure to UV photofunctionalization.

Conclusions

No significant effects were observed on osseointegration of dental titanium implants nine months after exposure of UV photofunctionalization.
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Two central features of Australian universities are a strong research base and a structural organisation which reflects a close relationship between teaching and research. Current policy deliberations have produced recommendations in the national interest for the future development of Australian university research which are incompatible with these two central features. The recommendations consolidate the recent trend towards greater centralisation, co-ordination, selectivity and concentration of university research and its funding. Although certain sectors of Australian university research will benefit from the changes, the recommendations reflect neither a longer term view of the total higher education system, nor a sufficient concern with preserving the excellent and productive qualities of the current system. Their implementation will mean the adoption of research goals inimical to the fundamental purposes of universities; a less flexible and more conservative research system; a re-orientation of the research role of universities so that it is less harmonious with their teaching role; and a potentially harmful differentiation of academic staff, subject areas and institutions. In responding to the new demands of government, universities face a challenge in preserving their current strengths and core functions.  相似文献   
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This study examines the relationship between some facets of organizational climate in university departments and faculty attitudes toward various aspects of faculty unionization. The dimensions of organizational climate explored are: the perceived power structure, assessment of rewards, and perceived organizational goals. The major findings of this study are: (a) The perceived power structure is an important determinant of attitudes toward an egalitarian system, especially in the social sciences. Perceived individual power is negatively related to egalitarian attitude in the physical sciences whereas perceived faculty group power is negatively related to favorable attitudes toward collective bargaining in the social sciences. (b) Perceived emphasis on consulting activities is positively related to attitudes toward seniority-based aspects of collective bargaining in the physical sciences while perceived emphasis on personal factors is positively related to all aspects of attitude toward collective bargaining in the social sciences. (c) Inequity is positively related to attitudes toward unionization both in the physical and social sciences. The policy implications of these findings to faculty and university administration are discussed.  相似文献   
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Journal of Science Education and Technology - Synergistic learning combining computational thinking (CT) and STEM has proven to be an effective method for advancing learning and understanding in a...  相似文献   
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The most important implication of the double-deficit hypothesis (Wolf & Bowers, in this issue) concerns a new emphasis on fluency and automaticity in intervention for children with developmental reading disabilities. The RAVE-O (Retrieval, Automaticity, Vocabulary Elaboration, Orthography) program is an experimental, fluency-based approach to reading intervention that is designed to accompany a phonological analysis program. In an effort to address multiple possible sources of dysfluency in readers with disabilities, the program involves comprehensive emphases both on fluency in word attack, word identification, and comprehension and on automaticity in underlying componential processes (e.g., phonological, orthographic, semantic, and lexical retrieval skills). The goals, theoretical principles, and applied activities of the RAVE-O curriculum are described with particular stress on facilitating the development of rapid orthographic pattern recognition and on changing children's attitudes toward language.  相似文献   
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Besides viewing knowledge about the nature of science (NOS) as important for its own value with respect to scientific literacy, an adequate understanding of NOS is expected to improve science content learning by fostering the ability to interrelate scientific concepts and, thus, coherently acquire scientific content knowledge. However, there is a lack of systematic investigations, which clarify the relations between NOS and science content learning. In this paper, we present the results of a study, conducted to investigate how NOS understanding relates to students’ acquisition of a proper understanding of the concept of energy. A total of 82 sixth and seventh grade students received an instructional unit on energy, with 41 of them receiving generic NOS instruction beforehand. This NOS instruction, however, did not result in students having higher scores on the NOS instrument. Thus, correlational analyses were performed to investigate how students’ NOS understanding prior to the energy unit related to their learning about science content. Results show that a more adequate understanding of NOS might relate to students’ perspective on the concept of energy and might support them in understanding the nature of energy as a theoretical concept. Students with higher NOS understanding, for example, seemed to be more capable of learning how to relate the different energy forms to each other and to justify why they can be subsumed under the term of energy. Further, we found that NOS understanding may also be related to students’ approach toward energy degradation—a concept that can be difficult for students to master—while it does not seem to have a substantive impact on students’ learning gain regarding energy forms, transformation, or conservation.  相似文献   
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