首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   128篇
  免费   5篇
教育   84篇
科学研究   23篇
各国文化   1篇
体育   8篇
文化理论   1篇
信息传播   16篇
  2023年   1篇
  2022年   4篇
  2021年   1篇
  2020年   4篇
  2019年   6篇
  2018年   14篇
  2017年   10篇
  2016年   5篇
  2015年   5篇
  2014年   11篇
  2013年   21篇
  2012年   5篇
  2011年   3篇
  2010年   4篇
  2009年   3篇
  2008年   3篇
  2007年   6篇
  2006年   3篇
  2005年   3篇
  2004年   2篇
  2002年   2篇
  2001年   1篇
  1999年   2篇
  1998年   2篇
  1997年   1篇
  1994年   4篇
  1992年   1篇
  1984年   1篇
  1982年   1篇
  1981年   1篇
  1979年   2篇
  1977年   1篇
排序方式: 共有133条查询结果,搜索用时 15 毫秒
21.
A 30‐s ‘all‐out’ power protocol was studied in four groups of racing cyclists including internationals (n = 8), Category 1 (n = 10), Category 2 (n = 15) and Category 3 (n = 11). Following warm‐up each subject completed five trials interspersed by 3 min of low intensity exercise on an ergowheel racing cycle ergometry system at a power output of 15 W kg–1 body weight, generated at 130 rev min–1. Temporal indices of performance included delay time (DT) to achieve the power criterion, total time (TT) of the maintenance of the power criterion and the ratio of TT/DT. ‘Explosive’ leg strength was assessed from a vertical jump. The results indicated that international and Category 1 cyclists had lower DT (2.2 ± 0.1s and 2.1 +0.0s, respectively; P<0.05), higher TT (28.1 ±0.7s and 27.0+0.7s, respectively; P<0.05) and elevated TT/DT (12.8 and 12.9, respectively; P<0.01). ‘Explosive’ leg strength was also higher (P<0.05) in the internationals than in the other groups of cyclists. The protocol provides a sport‐related method for the assessment of short term endurance performance ability in racing cyclists which may be of value in identifying the anaerobic capability of individual cyclists.  相似文献   
22.
The insulin-like growth factor 1 (IGF1) gene is a member of the group of somatotropin axis genes that play a significant role in cell proliferation and growth of muscles. Here, we searched for polymorphisms in buffalo IGF1 and found two novel single nucleotide polymorphisms (SNPs), G64A and G280A, in the noncoding sequences of exon 1 and exon 4, respectively. Statistical analysis of different genotypes showed that the individuals with GG genotypes had significantly (P<0.05) higher body weight (BW) and average daily gain (ADG) than those with other genotypes at ages of 3–6 months in G64A SNP and 6–9 months in G280A SNP. The combined genotypes of these two SNPs produced three haplotypes, GG/GG, AG/AG, and AA/AA, which were significantly associated (P<0.0001) with BW and ADG at an age from 3 to 12 months. Buffaloes with the homozygous GG/GG haplotype showed higher growth performance than other buffaloes. The two SNPs were correlated with mRNA levels of IGF1 and IGF1 receptor (IGF1R) in semitendinosus muscle as well as with the serum concentration level of IGF1. Also, buffaloes with GG/GG haplotype showed higher mRNA and serum concentration levels. The data revealed that these two SNPs could be valuable genetic markers for selection of Egyptian buffaloes for better performance in the population.  相似文献   
23.
Sharing of knowledge, information, and practices across cultural and national boundaries has become a means to address critical global problems. As government agencies increasingly collaborate with international counterparts on these issues, transnational knowledge and information sharing networks grow in importance as mechanisms for collaboration. This paper explores the nature of transnational public sector knowledge networks (TPSKNs) and identifies critical contextual factors that shape their performance. In these networks, each participating organization operates within complex national, organizational, and information contexts. The contextual differences between participants produce distances in culture, politics, intentions, organizational factors, relationships, knowledge, resources, geography, and technology. These distances influence their ability to engage in the processes and interactions that are essential to network performance. The paper concludes with a conceptual dynamic model that accounts for the relationships among these factors that can guide further research in understanding knowledge and information sharing across national and cultural boundaries.  相似文献   
24.
This paper discusses stress intensity factor (SIF) calculations for surface cracks in round bars subjected to combined torsion and bending loadings. Different crack aspect ratios, a/b, ranging from 0.0 to 1.2 and relative crack depths, a/D, ranging from 0.1 to 0.6 were considered. Since the loading was non-symmetrical for torsion loadings, a whole finite element model was constructed. Then, the individual and combined bending and torsion loadings were remotely applied to the model. The equivalent SIF method, F*EQ, was then used explicitly to combine the individual SIFs from the bending and torsion loadings. A comparison was then carried out with the combined SIF, F*FE, obtained using the finite element analysis (FEA) under similar loadings. It was found that the equivalent SIF method successfully predicted the combined SIF for Mode I. However, discrepancies between the results determined from the different approaches occurred when F III was involved. It was also noted that the predicted F*FE using FEA was higher than the F*EQ predicted through the equivalent SIF method due to the difference in crack face interactions.  相似文献   
25.
This study was conducted among Arab teachers in four countries in the Middle East (Jordan, Lebanon, Egypt and Palestine) to examine their views and methods on teaching for forgiveness in their classrooms. A total of 87 teachers in K-12 classrooms participated in semi-structured interviews as part of a larger study on teaching for forgiveness in the region. Thematic analyses of interviews suggested that teachers created opportunities to model and teach forgiveness as part of their civics education curriculum. They also expressed eagerness for instructional guidance and curriculum materials to systematically teach forgiveness in schools. The strength of religion and historical religious figures as positive sources for teaching forgiveness was also evident. Findings highlight the need to integrate education for peace and forgiveness in the education system, especially as a result of recent political developments in the Middle East, and to provide methods to assist teachers to do so in their classrooms.  相似文献   
26.
The kind and size of a library determines the need to collect and the method of controlling government publications. New Zealand libraries tend to handle these publications like any other book with the exception of official records and statistics. As a rule, public, rather than academic libraries, are the designated depositories. In comparing the concept of New Zealand libraries to that of the University of Oregon Library concerning government publications, I found that New Zealand libraries collect and store official and statistical publications and give them partial use; most government publications are integrated into the general collection (use is not known), and few libraries have separate government publication sections with special librarians governing the collection. On the other hand the University of Oregon collects all types of government publications for optimum use; many have been integrated into the general collection (use is not known); and a separate documents section is open to the public with several librarian specialists in attendance. Government publications in the general collection are not, as a rule, recognized as government publications by the public, but those publications are readily accessible. Many government publications at the University of Oregon Library are housed in the general collection, but since 1974 publications of the United States, Canada and many international organizations are shelved in the Documents Section. Use of the various classification schemes has proved successful; however, changes and improvements should be considered frequently to make the government publications collection the best able to serve the public.  相似文献   
27.
The aim of this article is to show the ways of implementing information technology into education in Kazakhstan based on the work of the Kazakhstan Institute of Management, Economics, and Strategic Research under the President of the Republic of Kazakhstan (KIMEP).  相似文献   
28.
This paper applies and extends Valsiner’s ‘zone theory’ (zones of free movement and promoted actions) through an examination of an intervention to establish inquiry communities in primary mathematics classrooms. Valsiner’s zone theory, in a classroom setting, views students’ freedom of choice of action and thought as mediated by the teacher. The extension of this theory adds that teachers’ freedom of choice of action and thought is mediated by ‘significant others’ and also by the actions of students with new freedoms. The paper presents necessary theoretical constructs and provides extracts from lessons and from teacher-teacher collaboration to illustrate the theoretical extension.  相似文献   
29.
In this paper we introduce a novel approach, relying on intelligent engineering, whereby the maximum speed limit at which vehicles on the road can cruise is controlled from some central or distributed facility. The system, as designed, leverages the use of the ubiquitous cellular infrastructure to cut down the costs involved that would otherwise accrue as a result of the need to build a dedicated traffic control system.In the new system maximum speed limits are transmitted from a Central Control Facility (CCF) to all stretches of roads and highways dispersed across urban areas in a highly dynamic manner. The system uses information arriving via a dynamic feedback system on prevailing weather conditions, road conditions, and bulk of traffic, amongst others, before it would broadcast maximum speed limit information to various destinations. When deployed in its final release, this will be done using a highly automated system with little human intervention.The work presented in this paper elaborates the TTC Network Design and RSU Network Distribution for the Tele-Traffic Speed Control System, to remotely manage, enforce, and control the maximum speed limit allowed on road stretches in rural and urban areas for different vehicle categories.The new system has been deployed successfully in a laboratory controlled environment on three vehicle categories; one category representing passenger vehicles, another buses and commuter transport, while the third representing trucks and freight traffic. It is expected that when the system is fully deployed on the wireless infrastructure, speed-related traffic accidents will witness a drop by more than 65-70% according to known accident statistics.  相似文献   
30.
The goal of this study was to determine the stability of Total Prostrate Specific antigen (PSA-T) and Free Prostrate Specific Antigen (PSA-F) in archival serum stored at 4°C and −20°C and subjected to temperature shift due to interruption in power supply. Our study showed that PSA-T was stable up to 285 days and PSA-F was stable for 158 days under these conditions. Since power supply interruption is an unavoidable problem in developing nations, our study has implication on the validity of measurement of PSA-T and PSA-F in serum that was not properly stored due to emergency situations and for certain types of retrospective studies.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号