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71.
  总被引:9,自引:0,他引:9  
This study employed a 2-year longitudinal design to examine the relation of stressful life events and social supports to psychological distress and school performance among 166 early adolescents (mean age = 13.5 years). A prospective approach was utilized to control for initial levels of adjustment when examining the relation of Time 1 stress and support variables to Time 2 psychological distress and school performance. Both stress and support variables made significant contributions to the prediction of subsequent psychological distress. Stresses, but not supports, made a significant contribution to the prediction of subsequent school performance. Evidence for reciprocal and interactive linkages was also found, including effects of psychological distress and school performance on subsequent stresses and supports, and greater adaptive impact of school-based supportive resources under conditions of heightened risk outside of school. Implications for ecological and transactional models of development relating to the targeting and efficacy of preventive efforts are discussed.  相似文献   
72.
    
We examined the Simple View of reading from a behavioral genetic perspective. Two aspects of word decoding (phonological decoding and word recognition), two aspects of oral language skill (listening comprehension and vocabulary), and reading comprehension were assessed in a twin sample at age 9. Using latent factor models, we found that overlap among phonological decoding, word recognition, listening comprehension, vocabulary, and reading comprehension was primarily due to genetic influences. Shared environmental influences accounted for associations among word recognition, listening comprehension, vocabulary, and reading comprehension. Independent of phonological decoding and word recognition, there was a separate genetic link between listening comprehension, vocabulary, and reading comprehension and a specific shared environmental link between vocabulary and reading comprehension. There were no residual genetic or environmental influences on reading comprehension. The findings provide evidence for a genetic basis to the “Simple View” of reading.  相似文献   
73.
Research and development (R&D) investment activity plays a crucial role in developing high-tech industries. In recent decades, China has made sustained investments in its domestic high-tech industries, with the goal of increasing their productivity. This paper investigates the effect of this investment on relative R&D efficiency across China's high-tech sectors. Data Envelopment Analysis (DEA) was used to generate quantitative indices for sector comparisons. The analysis of this study indicates that overall R&D investment efficiency did not increase from 1998 to 2009, despite R&D expenditure increasing by 2188%. Over the same period, most sectors suffered from decreasing returns to scale (DRS), presumably also reflecting the inefficient R&D investment. Most of the sectors showed significant fluctuation on R&D investment efficiency. This research result indicates that the problem of China's high-tech industry may be from the inefficiency of its technology commercialization processes, and therefore represents a critical parameter for policy makers and managers.  相似文献   
74.
Evidence on the persistence of innovation sheds light on the nature of the innovation process and can guide appropriate policy development. This paper examines innovation persistence in Ireland and Northern Ireland using complementary quantitative and case-study approaches. Panel data derived from innovation surveys is used, and suggests very different results to previous analyses of innovation persistence primarily based on patents data. Product and process innovation are found to exhibit strong general persistence but we find no evidence that persistence is stronger among highly active innovators. Our quantitative evidence is most strongly consistent with a process of cumulative accumulation at plant level. Our case-studies highlight a number of factors which can either interrupt or stimulate this process including market volatility, plants’ organisational context and regulatory changes. Notably, however, the balance of influences on product and process innovation persistence differs, with product innovation persistence linked more strongly to strategic factors and process changes more often driven by market pressures.  相似文献   
75.
Amplification of multiple unique genetic targets using the polymerase chain reaction (PCR) is commonly required in molecular biology laboratories. Such reactions are typically performed either serially or by multiplex PCR. Serial reactions are time consuming, and multiplex PCR, while powerful and widely used, can be prone to amplification bias, PCR drift, and primer-primer interactions. We present a new thermocycling method, termed thermal multiplexing, in which a single heat source is uniformly distributed and selectively modulated for independent temperature control of an array of PCR reactions. Thermal multiplexing allows amplification of multiple targets simultaneously—each reaction segregated and performed at optimal conditions. We demonstrate the method using a microfluidic system consisting of an infrared laser thermocycler, a polymer microchip featuring 1 μl, oil-encapsulated reactions, and closed-loop pulse-width modulation control. Heat transfer modeling is used to characterize thermal performance limitations of the system. We validate the model and perform two reactions simultaneously with widely varying annealing temperatures (48 °C and 68 °C), demonstrating excellent amplification. In addition, to demonstrate microfluidic infrared PCR using clinical specimens, we successfully amplified and detected both influenza A and B from human nasopharyngeal swabs. Thermal multiplexing is scalable and applicable to challenges such as pathogen detection where patients presenting non-specific symptoms need to be efficiently screened across a viral or bacterial panel.  相似文献   
76.
Regional investment in R&D, technological development and innovation is perceived as being strongly associated with productivity, growth and sustained international competitiveness. One policy instrument by which policy makers have attempted to create regional advantage has been the establishment of publicly funded research centres (PRCs). In this paper we develop a logic model for this type of regional intervention and examine the outputs and longer-term outcomes from a group of (18) publicly funded R&D centres. Our results suggest some positive regional impacts but also identify significant differences in terms of innovation, additionality and sustainability between university-based and company-based PRCs. University-based PRCs have higher levels of short-term additionality, demonstrate higher levels of organisational innovation but prove less sustainable. Company-based PRCs demonstrate more partial additionality in the short-term but ultimately prove more sustainable.  相似文献   
77.
    
This paper compares Bourdieu's notion of habitus with Bernstein's concept of code in an attempt to show how the apparent similarities mask more deeply seated differences in the way the concepts are conceived and used. We argue that Bernstein is following an essentially structuralist agenda of the kind that Bourdieu has set himself against. To this end, Bourdieu seeks to overcome the rigidities of ‘rules’ (which lie at the heart of the idea of Bernstein's code), with the more flexible notion of ‘strategy’ which incorporates the idea that structure and agency are implicit in each other rather than being dichotomous entities.  相似文献   
78.
The University of Southern California has conducted a series of 24 surveys of the professional activities of physicians and surgeons in the United States. The surveys encompass more than 10,000 respondents representing 65.8% of all practising physicians in the United States and its territories. Using a specially‐developed “log‐diary” recording instrument, these physicians reported data on the care they provided during hundreds of thousands of encounters with their patients. This article provides an exposition of the study's unique methodology, presents illustratative data for 5 of the 24 specialities surveyed (cardiology, family practice, general internal medicine, orthopaedic surgery and psychiatry), and discusses the study's relevance and implications for medical education.  相似文献   
79.
    
Students in a university special education course were shown three identical videotapes of children in a school setting. The subjects were randomly divided into three groups, each receiving different written background information (“positive,” “neutral,” or “negative”) prior to viewing the videotapes. It was found that the variations in written information had significant effects upon the subjects' perceptions of the children's behavior, and upon the degree to which the children were regarded as able to function successfully in a regular classroom. These findings suggest that attitudes toward exceptional children are influenced by the way in which prior information, such as that contained in a child's educational records, is presented. Teacher and peer acceptance of exceptional children can be increased if information is presented in a realistic and positive manner.  相似文献   
80.
    
Professional education in the future will require a different kind of relationship between the non-traditional student, the professional school, and the employer. Central to this new relationship is a recognition of the importance of acknowledging the areas of collaboration and institutionalizing these elements without ignoring the critical strengths of both institutions. This integration is most important in the professions of the future and especially the professions of human services.where his major commitment is to broaden the education and practice skills in each of the five undergraduate and graduate programs. He was formerly Dean of the College of Human Services in New York.  相似文献   
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