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1.
This study examined issues in supporting middle-school teachers to become more learner centered when implementing computer-based, workplace simulations in their classrooms. Specifically, this report focuses on a participant observation study of two teachers to develop and evolve a framework for professional development. The framework was developed based on prior professional development efforts, information on developing learner-centered classrooms, and data about teacher change. The framework included five key pieces: (a) reflection, (b) proximal goals, (c) collegial support groups, (d) one-on-one feedback, and (e) support materials for the teachers. The foundation for the framework was a belief that change is individual and needs to be supported in context and over time. The data included field observations as the teachers used the simulations in their classrooms made by the author and three outside observers, and interviews with each teacher following her use of the simulation program. During the four-month study, the original framework evolved in response to the data collected. The final version of the framework focuses on the professional developer working with teachers to develop reflective skills. Proximal goals became a focusing tool for reflection after teachers had begun to develop their reflective skills. The interplay between reflection and proximal goals was enhanced by outside resources, one-on-one feedback, and collegial group meetings. The work reported here was comp;eted as part of a dissertation conducted at Indiana University’s Center for Innovation in Assessment, and was supported in part by grants from the Andrew W. Mellon Foundation and the Russell Sage Fundation. The school and participant names have been changed to protect their identity. All researcher names are actual. 相似文献
2.
An estimate of water levels due to the interaction of tide and surge associated with a storm including air bubble effects is made along the coastal region of Bangladesh. For this purpose, a vertically integrated shallow water model in Cartesian coordinate system is developed introducing air bubbles and is solved using nested finite difference schemes. A fine grid model covering the region between 21°15′N to 23°N and 89°E to 92° E has been nested into a coarse grid model covering the region between 15°N to 23°N and 85°E to 95°E in the Bay of Bengal to incorporate all the major islands and coastal bending accurately. By applying tidal forcing through the southern open boundary of the coarse grid model appropriate tidal conditions are generated in the problem domain. Numerical experiments are performed with the help of the model to simulate water levels due to tide and surge interaction including air bubble effects associated with the tropical storm of April 1991. The model results are found to be reasonable and the model can be found to simulate higher water levels in the presence of air bubbles. 相似文献
3.
Sarama Saha Chandan Sarkar Subhash Chandra Biswas R. Karim 《Indian journal of clinical biochemistry : IJCB》2008,23(3):262-266
Abnormal lipid profile is often found in women with Polycystic Ovary Syndrome. To assess the impact of abnormal lipid profile on atherosclerosis in young Polycystic Ovary Syndrome women, carotid intima-media thickness as judged by B-mode ultrasonography were done in 30 young (18–35 yrs) Polycystic Ovary Syndrome women and in similarly age-matched 30 apparently healthy controls. Compared to controls, young Polycystic Ovary Syndrome women had significantly elevated serum total cholesterol, triglyceride and LDL-C levels and carotid intima-media thickness. HDL-C level did not differ significantly between two groups of women. In Polycystic Ovary Syndrome women carotid intima-media thickness was positively correlated with serum total cholesterol, triglyceride and LDL-C and negatively correlated with serum HDL-C. Our study suggests that even young Polycystic Ovary Syndrome women are prone to atherosclerosis from early age. 相似文献
4.
Chandra Hawley Orrill 《Distance Education》2002,23(1):41-57
This study considers how four groups of education graduate students worked in a distributed problem-based learning (PBL) environment using an asynchronous threaded discussion tool. The analyses consider how the students were able to interact with each other using the tool and how they worked together to define the problem and identify key issues to explore. The outcomes include some design considerations for tools to support these activities as well as insight about how students may work together to solve a problem in a distributed environment. 相似文献
5.
The motion of a projectile in a constant gravitational field is an age-old problem. If there is no resistive force, the problem is simple. However, with the intoduction of resistive forces, the complexity of the problem increases. Recently, there has been a growing interest in the problem of projectile motion under a resistive force proportional to the square of velocity. The problem for resistive force proportional to vv cannot be solved in closed analytical form. A series solution of the equation leads to divergent series for x (t) and y (t) for reasonable values of the initial speed and angle of projection. However, we demonstrate that by inverting the series for x (t), i.e., expressing t in terms of x, and substituting this in y (t) one can express y in terms of x which is a highly convergent series and one can obtain the path of projectile with a few terms of the series. We further demonstrate that one can obtain the path even with a few terms of the divergent series for x (t) and y (t) by using extrapolation methods. 相似文献
6.
Unstable angina is a critical condition of heart resulting from narrowing of vessels supplying blood to heart. Ischemia of
the myocardium leads to oxidative stress and severe tissue damage. The objective of the present study was to determine the
effect of l-arginine administration on the oxidant–antioxidant homeostasis which otherwise gets imbalanced in patients with cardiovascular
diseases. The results obtained, show improvement in the oxidant–antioxidant levels of the subjects upon incorporation of l-arginine. Our findings suggest that supplementation of l-arginine along with regular anti-anginal therapy may be beneficial to the patients of unstable angina. 相似文献
7.
8.
Souvik Ghosh H.N. Verma Dinesh Chandra P. Nanda 《The Journal of Agricultural Education and Extension》2013,19(1-4):17-26
The key to agricultural development in the eastern region of India, where problems of excess water and water scarcity coexist, is the scientific management of water resources with the adoption of recommended water-management technologies. A vast networking of infrastructure for the development and dissemination of water- management technologies have been designed since the very inception of planned economic change. Despite these concerted efforts, a large number of recommended technologies are either being adopted in piece-meal or not at all. The research and extension systems have been generating and disseminating technologies, therefore, it was felt worthwhile to assess the feasibility and appropriateness of recommended tecnologies as perceived in the first instance by the personnel of the research system and followed by the extension personnel. These steps were felt to be a precursor to screen the recommended technologies for their dissemination and evaluation in different farming systems. The assessment of recommended water-management technologies was performed after their documentation from different organisations working in the field of water management in two eastern India states viz. Orissa and West Bengal. The perception of 30 personnel members of the research system regarding the feasibility of these technologies elucidated that out of 86 documented recommended water-management technologies, 40 were having feasibility scores of ≥ 4.0; 8 technologies with score £ 3.0 and the rest of the 38 technologies with a score between 3.0 and 4.0 on a feasibility continuum range from 1.0 (not feasible) to 5.0 (highly feasible). Out of 40 recommended technologies (already assessed as highly feasible by the research personnel), extension personnel have perceived 16 and 10 technologies as highly appropriate and feasible, respectively. While six and four technologies were found to be less appropriate and feasible, respectively. Correlation of all nine indicators of appropriateness with feasibility of technologies was significant. Five indicators of appropriateness viz. simplicity, physical compatibility, production sustainability, cultural compatibility and cost together constituted 36.8 per cent of the total variation in feasibility with the ‘t’ values and ‘F’ values being significant. It indicates that not appropriateness of technologies alone but other factors influence the feasibility of technologies. 相似文献
9.
Singh PP Chandra A Mahdi F Roy A Sharma P 《Indian journal of clinical biochemistry : IJCB》2010,25(3):225-243
The antioxidants are essential molecules in human system but are not miracle molecules. They are neither performance enhancers
nor can prevent or cure diseases when taken in excess. Their supplemental value is debateable. In fact, many high quality
clinical trials on antioxidant supplement have shown no effect or adverse outcomes ranging from morbidity to all cause mortality.
Several Chochrane Meta-analysis and Markov Model techniques, which are presently best available statistical models to derive
conclusive answers for comparing large number of trials, support these claims. Nevertheless none of these statistical techniques
are flawless. Hence, more efforts are needed to develop perfect statistical model to analyze the pooled data and further double
blind, placebo controlled interventional clinical trials, which are gold standard, should be implicitly conducted to get explicit
answers. Superoxide dismutase (SOD), glutathione peroxidase and catalase are termed as primary antioxidants as these scavenge
superoxide anion and hydrogen peroxide. All these three enzymes are inducible enzymes, thereby inherently meaning that body
increases or decreases their activity as per requirement. Hence there is no need to attempt to manipulate their activity nor
have such efforts been clinically useful. SOD administration has been tried in some conditions especially in cancer and myocardial
infarction but has largely failed, probably because SOD is a large molecule and can not cross cell membrane. The dietary antioxidants,
including nutrient antioxidants are chain breaking antioxidants and in tandem with enzyme antioxidants temper the reactive
oxygen species (ROS) and reactive nitrogen species (RNS) within physiological limits. Since body is able to regulate its own
requirements of enzyme antioxidants, the diet must provide adequate quantity of non-enzymic antioxidants to meet the normal
requirements and provide protection in exigent condition. So far, there is no evidence that human tissues ever experience
the torrent of reactive species and that in chronic conditions with mildly enhanced generation of reactive species, the body
can meet them squarely if antioxidants defense system in tissues is biochemically optimized. We are not yet certain about
optimal levels of antioxidants in tissues. Two ways have been used to assess them: first by dietary intake and second by measuring
plasma levels. Lately determination of plasma/serum level of antioxidants is considered better index for diagnostic and prognostic
purposes. The recommended levels for vitamin A, E and C and beta carotene are 2.2–2.8 μmol/l; 27.5–30 μmol/l; 40–50 μmol/l
and 0.4–0.5 μmol/l, respectively. The requirement and recommended blood levels of other dietary antioxidants are not established.
The resolved issues are (1) essential to scavenge excess of radical species (2) participants in redox homeostasis (3) selective
antioxidants activity against radical species (4) there is no universal antioxidant and 5) therapeutic value in case of deficiency.
The overarching issues are (1) therapeutic value as adjuvant therapy in management of diseases (2) supplemental value in developing
population (3) selective interactivity of antioxidant in different tissues and on different substrates (4) quantitative contribution
in redox balance (5) mechanisms of adverse action on excess supplementation (6) advantages and disadvantages of prooxidant
behavior of antioxidants (7) behavior in cohorts with polymorphic differences (8) interaction and intervention in radiotherapy,
diabetes and diabetic complications and cardiovascular diseases (9) preventive behavior in neurological disorders (10) benefits
of non-nutrient dietary antioxidants (11) markers to assess optimized antioxidants status (12) assessment of benefits of supplementation
in alcoholics and heavy smokers. The unresolved and intriguing issues are (1) many compounds such as vitamin A and many others
possessing both antioxidant and non-antioxidant properties contribute to both the activities in vivo or exclusively only to
non-antioxidant activity and (2) since human tissues do not experience the surge of FR, whether there is any need to develop
stronger synthetic antioxidants. Theoretically such antioxidants may do more harm than good. 相似文献
10.
N. Chandra Shekhar K. Venkatasubbaiah N. R. Kandukuria 《European Journal of Engineering Education》2012,37(6):575-591
Measuring overall service quality (OSQ) is gaining prominence in higher education due to the increased competition among engineering education institutions (EEIs) and growing awareness about value for money among the public. Determination of OSQ on certain institutional aspects is done by various agencies throughout the world. Each system uses a different set of weighted indicators to measure the overall service quality of institutions. Five service quality factors, namely professionalism, integrated education, facilities, responsiveness and empathy are considered in the study. Trapezoidal fuzzy numbers are used to determine the aggregate weights of the factors to handle the vagueness present in the linguistic values of the stakeholders’ subjective opinions. Final weights of the factors are assessed by taking the distances of each factor between Fuzzy Positive Ideal Rating and Fuzzy Negative Ideal Rating. An illustrative study is presented to determine the OSQ of EEIs. The results help to focus on the factors which need immediate attention to enhance the quality of EEIs. 相似文献