全文获取类型
收费全文 | 675篇 |
免费 | 17篇 |
国内免费 | 1篇 |
专业分类
教育 | 429篇 |
科学研究 | 157篇 |
各国文化 | 5篇 |
体育 | 33篇 |
综合类 | 4篇 |
文化理论 | 6篇 |
信息传播 | 59篇 |
出版年
2023年 | 7篇 |
2022年 | 13篇 |
2021年 | 29篇 |
2020年 | 14篇 |
2019年 | 36篇 |
2018年 | 39篇 |
2017年 | 50篇 |
2016年 | 29篇 |
2015年 | 24篇 |
2014年 | 41篇 |
2013年 | 89篇 |
2012年 | 49篇 |
2011年 | 28篇 |
2010年 | 30篇 |
2009年 | 29篇 |
2008年 | 32篇 |
2007年 | 22篇 |
2006年 | 19篇 |
2005年 | 14篇 |
2004年 | 11篇 |
2003年 | 14篇 |
2002年 | 17篇 |
2001年 | 8篇 |
2000年 | 10篇 |
1999年 | 3篇 |
1997年 | 3篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1991年 | 4篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1980年 | 4篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1970年 | 1篇 |
1968年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有693条查询结果,搜索用时 15 毫秒
31.
Ali Tarhini Kate Hone Xiaohui Liu Takwa Tarhini 《Interactive Learning Environments》2017,25(3):306-328
In this study, we examine the effects of individual-level culture on the adoption and acceptance of e-learning tools by students in Lebanon using a theoretical framework based on the Technology Acceptance Model (TAM). To overcome possible limitations of using TAM in developing countries, we extend TAM to include subjective norms (SN) and quality of work life constructs as additional constructs and a number of cultural variables as moderators. The four cultural dimensions of masculinity/femininity (MF), individualism/collectivism, power distance and uncertainty avoidance were measured at the individual level to enable them to be integrated into the extended TAM as moderators and a research model was developed based on previous literature. To test the hypothesised model, data were collected from 569 undergraduate and postgraduate students using e-learning tools in Lebanon via questionnaire. The collected data were analysed using the structural equation modelling technique in conjunction with multi-group analysis. As hypothesised, the results of the study revealed perceived usefulness (PU), perceived ease of use (PEOU), SN and quality of work life to be significant determinants of students’ behavioural intention (BI) towards e-learning. The empirical results also demonstrated that the relationship between SN and BI was particularly sensitive to differences in individual-cultural values, with significant moderating effects observed for all four of the cultural dimensions studied. Some moderating effects of culture were also found for both PU and PEOU, however, contrary to expectations the effect of quality of work life was not found to be moderated by MF as some previous authors have predicted. The implications of these results to both theory and practice are explored in the paper. 相似文献
32.
Amna Khan Farzana Hayat Ahmad Muhammad Muddassir Malik 《Education and Information Technologies》2017,22(6):2767-2804
This study aimed to identify the impact of a game based learning (GBL) application using computer technologies on student engagement in secondary school science classrooms. The literature reveals that conventional Science teaching techniques (teacher-centered lecture and teaching), which foster rote learning among students, are one of the major concerns in Pakistan Education system. This leads to student disengagement in science lessons eventually resulting in student absenteeism and dropouts from the schools. This study consisted of five stages: (1) examining the impact of Digital Game-Based Learning (DGBL) and gamification on engagement, learning and gender difference, and literature related to using DGBL models for instructional design; (2) planning learning activities and developing a GBL application based on a specific content in Science; (3) conducting an intervention with a sample of 72 participants of 8th grade (aged 12–15) in a low cost private school of Pakistan following quasi-experimental research framework; (4) observing behaviour and emotions of the participants during science lessons; (5) conducting pre and post tests to assess the learning outcomes of participants followed by focus groups discussion. Analysis from Friedman test, Mann-Whitney U test, and Wilcoxon Signed Rank test show that the GBL application has a positive influence on student engagement. However, GBL application was not equally effective for all students since girls outperformed boys in terms of engagement and learning outcomes. This study gives insights into the development of better educational games to promote student learning. 相似文献
33.
FatimaEzzahra Benmarrakchi Jamal El Kafi Ali Elhore Sara Haie 《Education and Information Technologies》2017,22(6):2939-2957
Dyslexia is one of the most common learning disabilities. It is described as a disorder manifested by difficulty in learning to read despite conventional instruction, adequate intelligence, and sociocultural opportunity. It affects relatively about 7–10 % of the population across most languages and cultures. In this study, we explore the potential benefits offered by the use of Information and Communication Technology (ICT) to support dyslexic students by considering their preferred learning styles. In the current paper we administered the VAK and Honey & Mumford questionnaires to 28 Arabic students with ages between 8 and 10 years old. 8 students from dyslexic group and 20 students from control group were selected to assess and compare their preferred learning style. The implemented system focuses on dyslexia in Arabic language, especially in Arabic countries such as Morocco. Based on the results of the analysis of learning styles differences, we introduced an adaptive mobile learning to support and promote learning for dyslexic students. The aim of the study is to consider the relationship between dyslexia and learning style and to suggest a different learning way. Preliminary results show that the ICT has a valuable role in providing opportunities for learners with dyslexia to participate more fully in education. 相似文献
34.
Urinary abnormalities were evaluated in 100 renal stone patients with first episode of renal stone having age 22 to 45 years
from both sex and compared to 100 normal healthy control group having same age group from both sex. Twenty-four hours urinary
oxalate, calcium, uric acid, sodium, magnesium, phosphorus and citrate were estimated. The urinary pH was also determined.
In stone formers urinary oxalate, calcium, sodium and uric acid excretions were significantly higher when compared with control
group. Whereas citrate, phosphate and magnesium excretion were significantly lower in stone formers when compared with control.
The pH of urine in stone formers was lower than the controls. High dietary intake of purine rich diet causes elevated excretion
of uric acid, which leads to calcium oxalate crystal formation and precipitation. Other risk factors such as urinary oxalate,
calcium also related to formation of renal calculi.
Hypocitraturia is the main cause of renal calculi along with hypomagnesiuria and hypophosphaturia in the patient of Marathwada
region. On the basis of urinary abnormalities further stone formation in the patient can be prevented by dietary modifications. 相似文献
35.
The goal of the interval observers is to deal with the large but bounded uncertainties and disturbances by determining certain interval (upper and lower estimates) for the system states at each time instant. The mean of the interval that should be minimized can be considered as the point-wise estimate whereas the interval width provides the admissible deviation from that value. Thus, an interval estimation error bound is provided at any time instant that converges to zero in the absence of exogenous signals. Interval observers can be used in a wide range of applications because of its reliable uncertainties propagation such as robust control of linear and non-linear systems, fault detection and isolation, anti-disturbance controller design and so on. This paper presents some of the basic concepts and recent results obtained to design interval observers for uncertain systems like discrete-time, continuous-time, Linear Parameter Varying (LPV) systems and multiagent/interconnected systems. In addition, it also presents a brief discussion of the main approaches with some future recommendations. 相似文献
36.
This study examines the extent of concentration in the journal publishing industry. A number of aspects are considered: publishers, journal impacts, countries, and languages. For journals indexed in JCR from 1997 to 2009, just 0.2% of publishers produce 50% of journals and articles, and 0.3% of publishers account for the top 50% of citations, impact factors and immediacy indices. More than a half of publishers in JCR are from four countries: USA, UK, Germany and Japan. In addition, more than a half of journals come from the USA and UK. Examining the publishers' interactions in terms of buying and selling journals shows the extent of change by acquisition, and the acquisition links between publishers. The findings confirm that the international market of journal publishing is essentially dominated by a few publishers. 相似文献
37.
38.
Khan S Bhargava A Pathak N Maudar KK Varshney S Mishra PK 《Indian journal of clinical biochemistry : IJCB》2011,26(2):161-168
The present study evaluated the plausible role of circulating biomarkers in immune pathogenesis of chronic hepatitis considered
a priority in clinical hepatology. Total viral load of chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) patients
was quantified and correlation studies were performed with circulating levels of Th1/Th2 cytokines; C reactive protein and
circulating nucleosomes; glutathione reductase (GR) and superoxide dismutase. To our knowledge, the study is first among its
kind that validates strong positive correlation of viral load with IL-4, IL-6, GR in HBV and IL-6, IL-10, GR in HCV infections.
Although, multi-centric studies including large cohorts are required for translating our findings to clinical practice, however,
role of these biomarkers with potential diagnostic or prognostic significance might be helpful in clinical assessment of high-risk
individuals, thereby, designing interventional strategies, towards development of personalized medicare. The results of our
study also offer valuable insights of immune signaling mediators engaged in development of hepatocellular carcinoma. 相似文献
39.
Nitric oxide (NO) a free radical having both cytoprotective as well as tumor promoting agent is formed from l-arginine by converting it to l-citrulline via nitric oxide synthase enzymes. The reaction product of nitric oxide with superoxide generates potent oxidizing
agent, peroxynitrite which is the main mediator of tissue and cellular injury. Peroxynitrite is reactive towards many biomolecules
which includes amino acids, nucleic acid bases; metal containing compounds, etc. NO metabolites may play a key role in mediating
many of the genotoxic/carcinogenic effects as DNA damage, protein or lipid modification, etc. The basic reactions of nitric
oxide can be divided as direct effect of the radical where it alone plays a role in either damaging or protecting the cell
milieu and an indirect effect in which the byproducts of nitric oxide formed by convergence of two independent radical generating
pathways play the role in biological reactions which mainly involve oxidative and nitrosative stress. Nitric oxide is also
capable of directly interacting with mitochondria through inhibition of respiration or by permeability transition. Reaction
of nitric oxide with metal ions include its direct interaction with the metals or with oxo complexes thereby reducing them
to lower valent state. Excessive production of nitric oxide can be studied by inhibiting the synthetic pathway of nitric oxide
using both selective or specific nitric oxide synthase inhibitor or non-selective nitric oxide synthase inhibitor with respect
to isoforms of nitric oxide. 相似文献
40.
In this special issue of Biomicrofluidics, a wide variety of applications of microfluidics to tissue engineering and cell biology are presented. The articles illustrate the benefits of using microfluidics for controlling the cellular environment in a precise yet high rate manner using minimum reagents. The topic is very timely and takes a stab at portraying a glimpse of what is to come in this exciting and emerging field of research. 相似文献