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181.
Mouth rinsing using a carbohydrate (CHO) solution has been suggested to improve physical performance in fasting participants. This study examined the effects of CHO mouth rinsing during Ramadan fasting on running time to exhaustion and on peak treadmill speed (Vpeak). In a counterbalanced crossover design, 18 sub-elite male runners (Age: 21?±?2 years, Weight: 68.1?±?5.7?kg, VO2max: 55.4?±?4.8?ml/kg/min) who observed Ramadan completed a familiarization trial and three experimental trials. The three trials included rinsing and expectorating a 25?mL bolus of either a 7.5% sucrose solution (CHO), a flavour and taste matched placebo solution (PLA) for 10?s, or no rinse (CON). The treatments were performed prior to an incremental treadmill test to exhaustion. Three-day dietary and exercise records were obtained on two occasions and analysed. Anthropometric characteristics were obtained and recorded for all participants. A main effect for mouth rinse on peak velocity (Vpeak) (CHO: 17.6?±?1.5?km/h; PLA: 17.1?±?1.4?km/h; CON: 16.7?±?1.2?km/h; P?ηp2?=?0.49) and time to exhaustion (CHO: 1282.0?±?121.3?s; PLA: 1258.1?±?113.4?s; CON: 1228.7?±?98.5?s; P?=?.002, ηp2?=?0.41) was detected, with CHO significantly higher than PLA (P?P?P?>?.05). Energy availability from dietary analysis, body weight, and fat-free mass did not change during the last two weeks of Ramadan (P?>?.05). This study concludes that carbohydrate mouth rinsing improves running time to exhaustion and peak treadmill speed under Ramadan fasting conditions.  相似文献   
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183.
ABSTRACT

This paper analyzes the process of crack saturation, which is fundamental to understanding why panel paintings have survived remarkably well in the uncontrolled environments of historic houses or places of worship for several centuries. The process of crack saturation was analyzed using finite element modeling. A double layer elastic model with fractured overlying paint layer was subjected to uniaxial tension. The critical separation between cracks was determined and compared with patterns observed in real paintings. In addition, the generation and propagation of delamination were studied to elucidate the effect of their propagation on the saturation distance of cracks, as well as the load carrying ability of the paint layer. Contributing modes of crack propagation and their significance are also discussed. The results demonstrate that shearing fracture mode dominates the process of delamination. The impact of crack saturation on the degree of relative humidity variation that is allowable is also discussed.  相似文献   
184.
Several authors have proposed that a large number of unusual combinations of cited references in a paper point to its high creative potential (or novelty). However, it is still not clear whether the number of unusual combinations can really measure the creative potential of papers. The current study addresses this question on the basis of several case studies from the field of scientometrics. We identified some landmark papers in this field. Study subjects were the corresponding authors of these papers. We asked them where the ideas for the papers came from and which role the cited publications played. The results revealed that the creative ideas might not necessarily have been inspired by past publications. The literature seems to be important for the contextualization of the idea in the field of scientometrics. Instead, we found that creative ideas are the result of finding solutions to practical problems, result from discussions with colleagues, and profit from interdisciplinary exchange. The roots of the studied landmark papers are discussed in detail.  相似文献   
185.
Objective: To develop a new bioinformatic tool based on a data-mining approach for extraction of the most infor-mative proteins that could be used to fred the potential biomarkers for the detection of cancer. Methods: Two independent datasets from serum samples of 253 ovarian cancer and 167 breast cancer patients were used. The samples were examined by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS). The datasets were used to extract the informative proteins using a data-mining method in the discrete stationary wavelet transform domain. As a dimensionality re-duction procedure, the hard threshoiding method was applied to reduce the number of wavelet coefficients. Also, a distance measure was used to select the most discriminative coefficients. To find the potential biomarkers using the selected wavelet coefficients, we applied the inverse discrete stationary wavelet transform combined with a two-sided t-test. Results: From the ovarian cancer dataset, a set of five proteins were detected as potential biomarkers that could be used to identify the cancer patients from the healthy cases with accuracy, sensitivity, and specificity of 100%. Also, from the breast cancer dataset, a set of eight proteins were found as the potential biomarkers that could separate the healthy cases from the cancer patients with accuracy of 98.26%, sensitivity of 100%, and specificity of 95.6%. Conclusion: The results have shown that the new bioinformatic tool can be used in combination with the high-throughput proteomic data such as SELDI-TOF MS to find the potential biomarkers with high discriminative power.  相似文献   
186.
Drawing on sociocultural theory, and a large number of empirical studies conducted on the effectiveness of scaffolding on second or foreign language learning, the authors investigated the application of different forms of scaffolding to improve listening comprehension of the Iranian intermediate English as a foreign language (EFL) learners. To this end, 90 intermediate EFL learners were randomly assigned to 2 experimental groups and a control group. During 15 treatment sessions of listening comprehension instruction, expert peers in the first experimental group assisted their less knowledgeable peers in their listening comprehension tasks. The participants in the second experimental group were asked to assist their coequal peers while doing the listening comprehension tasks, but the participants in group 3 did not interact with each other or even their teacher and no scaffolding scheme was used when they were doing the listening comprehension tasks. One-way analysis of variance and post hoc analyses revealed that the expert peers' scaffolding was the most effective procedure for the intermediate EFL learners' listening comprehension development. Furthermore, coequal peers' scaffolding was proved to be the second effective procedure for the listening comprehension improvement. The findings underscore the relative efficacy of different forms of scaffolding procedure and the superiority of the expert peers' scaffolding over coequals' scaffolding. The qualitative analysis of the recorded data indicated that the implicit scaffolding strategies were more frequently used by the expert peers. However, the explicit scaffolding strategies were more frequently used to by the coequals. The findings of the study underscore the positive potentiality of scaffolding in its different forms for the EFL learners' listening comprehension development.  相似文献   
187.
Students’ perception of assessment methods plays a significant role in determining their effort towards learning and their assessment tasks. Similar to the role of goal orientation in predicting students’ classroom learning, this study aims to examine how students’ goal orientations influence their perception of classroom assessments. Using a qualitative research design, the data was collected from 41 students enrolled in master’s degree programme at a public university in northern Malaysia, using reflection notes and semi-structured interviews. Data was analysed using a typological approach to inductively develop the categories. The findings demonstrated that perception of mastery goal oriented students considerably contrasted with those with performance goal orientation. The distinctions in perception is discussed under four categories: assessment as a process or product, preferences for modes, reasons for effort and feeling and emotions. The implications of the findings are discussed for higher education practitioners.  相似文献   
188.
Learning Environments Research - The purpose of present study was to examine the effect of friendship and relationship dimensions of the classroom environment on general and academic selfconcept....  相似文献   
189.
The use of an effective supervision mechanism is crucial between a student and supervisor. The essential knowledge shared and transferred between these two parties must be observed and understood very well in order to ensure that students are produced at good level of quality for future professional knowledge workers. The aim of this study was to conduct an assessment of the impact of individual, organisational and technical factors on knowledge sharing in a research supervision domain. In order to achieve this aim, a specific research model was developed. This model was based on systematically analysing and extracting all the knowledge-sharing impact factors and then choosing the more iterative and adaptable ones, according to research supervision models. These factors categorized to individual, organizational and technological factors. To effectively evaluate the research model, a quantitative research method was adopted. Data was collected by a survey of 150 students from the Faculty of Computing at Universiti Teknologi Malaysia. The Smart PLS tool was used for data analysis. In sum, the results of this research show that the individual factor in the research supervision domain – namely, the ability of students to share knowledge – in addition to technological factors – specifically, IT systems – have the greatest impact on knowledge sharing in the supervision process. In addition, it was shown that organisational factors including the culture of the university, social networks, and supervisor support have a positive impact on knowledge sharing in research supervision. However, when compared with individual and technical factors, the effect of organisational factors on knowledge sharing in research supervision was not particularly strong in the case of this study. A positive relationship did not exist between the learning strategy and knowledge sharing in research supervision. This study is among the first of its kind to empirically examine the antecedent factors of knowledge sharing in the context of research supervision.  相似文献   
190.
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