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81.
The association among mothers', fathers', and infants' risk and cognitive and social behaviors at 24 months was examined using structual equation modeling and data on 4,200 on toddlers and their parents from the Early Childhood Longitudinal Study, Birth Cohort. There were 3 main findings. First, for cognitive outcomes, maternal risk was directly and indirectly linked to it through maternal sensitivity whereas paternal risk was only indirectly related through maternal sensitivity. Second, for social behaviors, maternal and paternal risks were indirectly linked through maternal sensitivity and father engagement. Third, maternal and paternal levels of risk were linked to maternal supportiveness whereas mothers' and children's risk were linked to paternal cognitive stimulation. Implications are that policy makers must take into account effects of mothers', children's, and fathers' risk on young children's functioning.  相似文献   
82.
We report a case of a diabetic, heterozygote with near normal hematology, marginally low level of hemoglobin A2(HbA2) having an increased level of hemoglobin F(HbF) that was pancellularly distributed among the red cells. BioRad DiaSTAT measurements gave a high glycated hemoglobin A1c(HbA1c) of 31.5% and the BioRad Variant analyzer recorded an HbA1c value which was very low, in discordance with the detected blood glucose levels. Flow cytometry and polymerization chain reaction (PCR) based studies were carried out which revealed the case to be that of the common hereditary persistence of fetal hemoglobin (HPFH)-3, an Asian Indian mutation. Fructosamine estimation and HbA1c by Boronate affinity chromatography were able to resolve the discordant value detected and was able to confirm the diabetes status. The case would have been a diagnostic dilemma, if reported without correlation.  相似文献   
83.
The world of mobile communications is poised for yet another disruptive transformation – the introduction of 5G. It will change the way mobile phones communicate. New technologies at the device level and novel network architectures to manage them will be soon seen everywhere. This article explores what 5G is all about. It also talks briefly about the preparations underway across the globe to deploy 5G by 2020.  相似文献   
84.
85.
The impact of misspecifying covariance matrices at the second and third levels of the three-level model is evaluated. Results indicate that ignoring existing covariance has no effect on the treatment effect estimate. In addition, the between-case variance estimates are unbiased when covariance is either modeled or ignored. If the research interest lies in the between-study variance estimate, including at least 30 studies is warranted. Modeling covariance does not result in less biased between-study variance estimates as the between-study covariance estimate is biased. When the research interest lies in the between-case covariance, the model including covariance results in unbiased between-case variance estimates. The three-level model appears to be less appropriate for estimating between-study variance if fewer than 30 studies are included.  相似文献   
86.
INTRODUCTION The physics of plastic deformation and crack propagation at atomic level is complex but is essential for the development of new materials. This requires an understanding of the atomic level phenomena associated with the plastic deformation. In this con- text, emission of electromagnetic radiation (EMR) during plastic deformation and crack propagation in metals and alloys, and generation of transient mag- netic fields during crack initiation in ferromagnetic materials are rep…  相似文献   
87.
This study examines the use of cross-classified random effects models (CCrem) and cross-classified multiple membership random effects models (CCMMrem) to model rater bias and estimate teacher effectiveness. Effect estimates are compared using CTT versus item response theory (IRT) scaling methods and three models (i.e., conventional multilevel model, CCrem, CCMMrem). Results indicate that ignoring rater bias can lead to teachers being misclassified within an evaluation system. The best estimates of teacher effectiveness are produced using CCrems regardless of scaling method. Use of CCMMrems to model rater bias cannot be recommended based on the results of this study; combining the use of CCMMrems with an IRT scaling method produced especially unstable results.  相似文献   
88.
Satish Kumar 《Resonance》1999,4(4):45-55
In Part 1 of this article we understood the idea of a fuzzy set. We also reviewed simple operations such as fuzzy set intersection, union, and complementation, and related these to geometry. In Part 2, we extend the idea of fuzzy sets to explain how we may develop systems that reason with fuzzy sets using fuzzy logic. The idea of extending fuzzy logic to fuzzy engineering and fuzzy function approximation is explored with a working example. It is hoped that readers will be provided with enough motivation to appreciate the use of fuzzy set theory for real world applications.  相似文献   
89.
The use of fiction and autobiography in social science course work has been shown to enhance students' learning experience. Using the novel PUSH, by Sapphire, we designed a curriculum supplement for the social work course, human behavior and the social environment (HBSE) that encourages students to integrate course content in an innovative way and enables them to apply the material to life-like situations. The HBSE supplement allows students to explore poignant and problematic issues that push them past intrapersonal and interpersonal limits. Classes are infused with energy and the critical consciousness of the students. Final projects are a systematic case study of a chosen character (or characters) in the book and are a testament to student critical thinking and creativity. Methods, assignments, and student experiences in an introductory BSW course are described.  相似文献   
90.
Differential Item Functioning (DIF) is traditionally used to identify different item performance patterns between intact groups, most commonly involving race or sex comparisons. This study advocates expanding the utility of DIF as a step in construct validation. Rather than grouping examinees based on cultural differences, the reference and focal groups are chosen from two extremes along a distinct cognitive dimension that is hypothesized to supplement the dominant latent trait being measured. Specifically, this study investigates DIF between proficient and non-proficient fourth- and seventh-grade writers on open-ended mathematics test items that require students to communicate about mathematics. It is suggested that the occurrence of DIF in this situation actually enhances, rather than detracts from, the construct validity of the test because, according to the National Council of Teachers of Mathematics (NCTM), mathematical communication is an important component of mathematical ability, the dominant construct being assessed. However, the presence of DIF influences the validity of inferences that can be made from test scores and suggests that two scores should be reported, one for general mathematical ability and one for mathematical communication. The fact that currently only one test score is reported, a simple composite of scores on multiple-choice and open-ended items, may lead to incorrect decisions being made about examinees.  相似文献   
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