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51.
期刊评价:影响因子及其相关指标   总被引:2,自引:2,他引:2  
在西部大开发环境下,联系陕西省科技期刊的现状,研究了陕西省科技期刊的发展策略,首次提出“寓发展于服务中、中陕西省科技期刊与西部大开发的结合点。指出陕西省科技期刊发展的基本原则是坚持两个效益辩证统一,发展的出发点是服务西部大开发。  相似文献   
52.
A high ambient temperature reduces the capacity to perform prolonged exercise. Total carbohydrate oxidation is less, and thus glycogen depletion is not limiting. Fluid ingestion in the heat should, therefore, focus on maintenance of hydration status rather than on substrate provision. Six healthy males cycled to exhaustion at 60% of maximum oxygen consumption (VO 2max ) with no drink, ingestion of a 15% carbohydrate-electrolyte drink (1.45 - 0.29 litres) or ingestion of a 2% carbohydrate-electrolyte drink (3.12 - 0.47 litres). The ambient temperature was 30.2 - 0.6°C (mean - s ), with a relative humidity of 71 - 1% and an air speed of approximately 0.7 m.s -1 on all trials. Weighted mean skin temperature, rectal temperature and heart rate were recorded and venous samples drawn for determination of plasma volume changes, blood metabolites, serum electrolytes and osmolality. Expired gas was collected to estimate rates of fuel oxidation. Exercise capacity was significantly ( P ? 0.05) different in all trials. The median (range) time to exhaustion was 70.9 min (39.4-97.4 min) in the no-drink trial, 84.0 min (62.7-145 min) in the 15% carbohydrate trial and 118 min (82.6-168 min) in the 2% carbohydrate trial. The 15% carbohydrate drink resulted in significantly ( P ? 0.05) elevated blood glucose and total carbohydrate oxidation compared with the no-drink trial. The 2% carbohydrate drink restored plasma volume to pre-exercise values by the end of exercise. No differences were observed in other thermoregulatory or cardiorespiratory responses between trials. These results suggest that fluid replacement with a large volume of a dilute carbohydrate drink is beneficial during exercise in the heat, but the precise mechanisms for the improved exercise capacity are unclear.  相似文献   
53.
ABSTRACT

The aims and content of training in special education have been extended in recent years as a result of the practice of integrated education and also the recognition of a larger group of children with special educational needs. Provision in ordinary schools is being seen as the development of whole‐school policies for curricula and organization, including the development of systems of support within and sometimes, across schools. These developments have implications for the training of special education teachers and also for the pre‐service and in‐service education and training of all teachers and for the variety of strategies to be employed.  相似文献   
54.
Pedagogical innovation—whether involving technology or not—is shaped by a complex interaction of the innovation with contextual factors such as school and school district policy, leadership, cultural norms and values, teacher attitudes and skills, and student characteristics. This study examined school and classroom contexts in which pedagogical innovations employing technology were successfully sustained. Data were obtained from 59 cases drawn from the Second Information Technology in Education Study—Module 2, a project that examined 174 cases of innovative pedagogical practice in schools in 28 countries. An explanatory model of sustainability was derived from a qualitative analysis of the cases using grounded theory techniques. Essential conditions for the sustainability of classroom innovation were teacher and student support of the innovation, teacher perceived value of the innovation, teacher professional development, and principal approval. Contributing factors for sustainability were supportive plans and policies, funding, innovation champions, and internal and external recognition and support. An interactive website that allows for searching of SITES-M2 case reports on various attributes such as sustainability, transferability, level of school, and evidence of supportive policies and plans is available at http://sitesm2.org.  相似文献   
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56.
Social media challenge knowledge management because of encouraging conversations, networking and participation in more distributed, diverse and dynamic ways of knowledge development and increasingly important individuals’ interests driving them. Hence, we need to understand the complex relationships between different qualities of knowledge developed in informal and formal processes as well as for overcoming misalignments in routines, tools and infrastructures supporting organizational knowledge creation. This paper contributes a maturation perspective towards explaining organizational knowledge creation and presents a knowledge maturing model, which is grounded in organizational practice and validated with qualitative and quantitative empirical and design studies. The results describe how characteristics of knowledge and support by IT change between phases of knowledge maturing. Our findings confirm theories of organizational knowledge creation with respect to expanding scopes from individuals through communities to organizations moving from interest-driven knowledge exploration in informal contexts to goal-driven knowledge exploitation in formal contexts. The maturation perspective adds to our understanding that organizational knowledge creation is not simply a continuous process. Phases that emphasize changeability alternate with phases concerned with stability. Knowledge develops in contexts that need to switch multiple times between opening up for new knowledge and filtering relevant knowledge and between de- and re-contextualization.  相似文献   
57.
This article proposes the coresearch engagement model (CoRE), which addresses how the academic research librarian can become a coresearch partner with any patron. The CoRE model is an interpersonal process and is founded upon the concepts of mutual respect, collaboration, reciprocity, and empowerment. Grounded in Howard Gardner’s multiple intelligences theory, Malcolm Knowles’ andragogical model, and guidelines from the Reference and User Services Association, CoRE has the potential to result in engagement for the librarian and patron. The CoRE model can be utilized in many ways including self-awareness and development for those who need and want to expand their abilities as a research librarian. It provides a theoretical framework and a knowledge base, in addition to giving a context for further development by expanding, comparing the related theories for further research, and implementing various applications suggested by this article.  相似文献   
58.
Intellectual performance is highly heritable and robustly predicts lifelong health and success but the earliest manifestations of genetic effects on this asset are not well understood. This study examined whether early executive function (EF) or verbal performance mediate genetic influences on subsequent intellectual performance, in 561 U.S.-based adoptees (57% male) and their birth and adoptive parents (70% and 92% White, 13% and 4% African American, 7% and 2% Latinx, respectively), administered measures in 2003–2017. Genetic influences on children's academic performance at 7 years were mediated by verbal performance at 4.5 years (β = .22, 95% CI [0.08, 0.35], p = .002) and not via EF, indicating that verbal performance is an early manifestation of genetic propensity for intellectual performance.  相似文献   
59.
Research into invention, innovation policy, and technology strategy can greatly benefit from an accurate understanding of inventor careers. The United States Patent and Trademark Office does not provide unique inventor identifiers, however, making large-scale studies challenging. Many scholars of innovation have implemented ad-hoc disambiguation methods based on string similarity thresholds and string comparison matching; such methods have been shown to be vulnerable to a number of problems that can adversely affect research results. The authors address this issue contributing (1) an application of the Author-ity disambiguation approach (0170 and 0175) to the US utility patent database, (2) a new iterative blocking scheme that expands the match space of this algorithm while maintaining scalability, (3) a public posting of the algorithm and code, and (4) a public posting of the results of the algorithm in the form of a database of inventors and their associated patents. The paper provides an overview of the disambiguation method, assesses its accuracy, and calculates network measures based on co-authorship and collaboration variables. It illustrates the potential for large-scale innovation studies across time and space with visualizations of inventor mobility across the United States. The complete input and results data from the original disambiguation are available at (http://dvn.iq.harvard.edu/dvn/dv/patent); revised data described here are at (http://funglab.berkeley.edu/pub/disamb_no_postpolishing.csv); original and revised code is available at (https://github.com/funginstitute/disambiguator); visualizations of inventor mobility are at (http://funglab.berkeley.edu/mobility/).  相似文献   
60.
Graduation patterns were examined for 905 deaf students (1990-1998) at the National Technical Institute for the Deaf. Students with higher reading and language skills had the best overall graduation percentage. Comparison of recipients of different degrees--bachelor of science (BS) versus fine arts (BFA); associate of applied science (AAS) versus occupational studies (AOS)--showed 92% of BS and 82% of AAS graduates reading at the 9th-grade level or above, versus 65% of BFA and 47% of AOS graduates. Interestingly, 80% of non-degree-earning students read at the 9th-12th grade levels; in absolute terms, they outnumbered graduates with similar reading skills in the AAS and BFA programs combined, and in the BS program. This indicates a need for improved counseling, placement, and retention strategies. Students performed similarly across degree categories, regardless of curriculum requirements and difficulty. Only non-degree-earning students had significantly lower grade averages.  相似文献   
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