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991.
Growing recognition of the complexity of children’s lives has led to strong advocacy in education research literature for greater collaboration between researchers from different paradigms to address the ‘wicked’ problems that face contemporary children and families. There is little literature, however, exploring how collaboration works in practice. This paper, drawing on researcher reflective narrative, and using Cultural Historical Activity Theory as a heuristic framework, describes and critiques the formative stages of an educational research collaborative group of five early and one mid-career early childhood education researchers (the authors), from two universities, and with quite different epistemological and ontological understandings. It outlines, from an insider perspective, some of the outcomes, challenges and tensions associated with participating in the research group, and concludes by providing some implications for policy and considerations for those contemplating forming a collaborative group.  相似文献   
992.
The vapor-liquid equilibrium(VLE) properties for the binary and ternary mixtures of CH4,C2H4 and isoC4H10 are of great importance in the recovery of ethylene from mixture containing CH4 and C2H4 with iso-C4H10 as solvent.Hence,Gibbs ensemble Monte Carlo(GEMC) simulations were used to estimate vapor-liquid equilibrium for the binary and ternary mixtures of CH4,C2H4 and iso-C4H10 with the united atom potential NERD model.The selected simulation conditions are based on the experiment in the literature.The results of this work were shown to be in satisfactory agreement with available experimental data and predictions of Peng-Robinson equation of state.The structure of simulated liquid phase is also characterized by radial distribution function(RDF),which contributes to further understanding of the VLE curve of these systems.RDF is not sensitive to the pressure and temperature range.With the increase of pressure or the decrease of temperature,the molecules tend to gather together.  相似文献   
993.
994.
This study was based on Hovland's four-part statement, “Who says what to whom with what effect,” the rationale for persuasive communication, a theoretical model for modifying attitudes. Part I was a survey of 139 perservice elementary teachers from which were generated the more credible characteristics of metric instructors, a central element in the “who” component of Hovland's model. They were: (1) background in mathematics and science, (2) fluency in metrics, (3) capability of thinking metrically, (4) a record of excellent teaching, (5) previous teaching of metric measurement to children, (6) responsibility for teaching metric content in methods courses and (7) an open enthusiasm for metric conversion. Part II was a survey of 45 mathematics educators where belief statements were synthesized for the “what” component of Hovland's model. It found that math educators support metric measurement because: (1) it is consistent with our monetary system; (2) the conversion of units is easier into metric than English; (3) it is easier to teach and easier to learn than English measurement; there is less need for common fractions; (4) most nations use metric measurement; scientists have used it for decades; (5) American industry has begun to use it; (6) metric measurement will facilitate world trade and communication; and (7) American children will need it as adults; educational agencies are mandating it. With the “who” and “what” of Hovland's four-part statement defined, educational researchers now have baseline data to use in testing experimentally the effect of persuasive communication on the attitude of preservice teachers toward metrication.  相似文献   
995.
The view that imagery might be a disadvantage on certain tasks might surprise some mathematics educators who contend that a learner's conceptual understanding is increased whenever visual imagery is used. One of the limitations of imagery found in the literature comes to bear on a unique aspect of mathematics teaching and learning. This is the notion of an uncontrollable image, which may persist, thereby preventing the opening up of more fruitful avenues of thought, a difficulty which is particularly acute if the image is vivid. Although one calculus student's images supported high levels of mathematical functioning, occasionally his vivid images became uncontrollable, and the power of these images did more to obscure than to explain. This type of imagery can be a major hindrance in constructing meaning for mathematical concepts — contrary to the panacea view of imagery which is sometimes expressed.This revised version was published online in September 2005 with corrections to the Cover Date.  相似文献   
996.
DBA/2J mice were exposed to a distinctive floor stimulus (CS+) and ethanol (2 g/kg) in a place conditioning paradigm. A different floor stimulus (CS?) was presented with saline. Mice injected just before or 30 min before CS exposure (Groups 0, ?30) showed conditioned place preference, whereas mice injected right after exposure to the CS (Group 5) displayed place aversion (Experiment 1). None of the other groups (?120, ?60, 15, 60) showed place conditioning. Handling and saline injection given just before or after CS exposure were unable to produce place conditioning (Experiment 2). However, there was a positive relationship between ethanol concentration (10% vs. 20%) and test performance, suggesting that peritoneal irritation influences place conditioning (Experiment 3). Overall, these findings support the suggestion that intraperitoneal injection of ethanol produces an initial short-duration aversive effect that is followed by a longer lasting positive motivational effect.  相似文献   
997.
In this contribution, a theoretical and empirical framework based on work carried out at the Open universiteit (Ou) for a new approach towards the design, production and delivery of flexible, interactive learning materials for distance education is presented.

In the Research and Development centre of the Ou, a project has concentrated on the innovation of current approaches. This framework can also be considered as an advance organizer to reading the remaining articles from the Open universiteit in this issue of Distance Education.

A key feature of the innovation is that during the design phase, course developers have to define ‘models’ of the materials to be developed: a content model, a support model, a student model and the learning path. From a flexibility point of view especially, the ‘student model’ is of importance since it defines the student variables that will be taken into account when developing/ presenting alternative materials (basic content and/or embedded support). A computer‐based system, the ‘Interactive Learning and Course Development Environment (ILCE)’, was developed to support the work of course development teams and tutors on the one hand, and students on the other hand. The development system supports the work of the developers; the delivery system supports the study process of students. The delivery is realised as an on‐line course, on the World Wide Web.

Students start working with the ILCE‐system by following an intake procedure. They can make choices in relation to student variables that have been defined in the student model (profession, study intentions, context, etc.). Next, they can ‘on the fly’ generate a course. Rom the large repository of learning materials only those materials are selected and compiled that are in line with the student model of this specific student Furthermore, they can choose to study the materials on screen and/or make prints of the materials. Of course, in printing the materials they lose the interactive and dynamic possibilities of the computer learning environment  相似文献   

998.
This study deals with the initial understanding that advanced undergraduate mathematics students exhibit when presented with a new concept in an environment requiring self-generation and self-validation of instances of the concept. Data were collected in spring of 1995 through interviews with 11 third and fourth year undergraduate mathematics students. We discuss the data from the perspective of the student's concept image and introduce the notion of learning event to indicate when a student communicates and applies a new understanding of a concept. We infer that the students in our study who employed an example generation learning strategy were more effective in attaining an initial understanding of the new concept than those who primarily employed other learning strategies such as definition reformulation or memorization.This revised version was published online in September 2005 with corrections to the Cover Date.  相似文献   
999.
This study tested the effects of an entrepreneurship education intervention, the New Youth Entrepreneur curriculum, on lower socioeconomic black high-school students' knowledge of basic and advanced concepts in entrepreneurship. Ninety-five high school sophomores (over 85% black) from a lower socioeconomic neighborhood made up the sample for the experimental design: 51 in the treatment group and 44 in the control group. The two instruments used measured participants' knowledge of basic entrepreneurship concepts and higher cognitive levels of entrepreneurship learning, including comprehension, application, and analysis. The treatment group experienced the New Youth Entrepreneur (NYE) curriculum for one period a day for a semester, while the control group was exposed to basic entrepreneurship concepts at an awareness level as part of a general business education course. It was predicted and found that the treatment group significantly outperformed the control group on all dimensions of entrepreneurship tested. The study results confirm that appropriate curricular innovation can significantly influence the acquisition of entrepreneurship concepts and skills by lower socioeconomic black students. They also confirm that these same students can even be energized to the point of moving from opportunity recognition to initial business implementation.  相似文献   
1000.
Objective: With the rapid rise of sexual abuse allegations, there is a growing need to develop instruments to help clinicians determine the likelihood that sexual abuse has occurred.Method: This study evaluated the discriminant validity of a structured parent interview regarding emotional, behavioral, and physical symptoms by comparing results among three subsamples of age matched boys: 22 sexually abused boys whose perpetrator confessed, 47 boys evaluated in a sexual abuse clinic but without a history of perpetrator confession and 52 nonabused boys selected after rigorous screening.Results: In comparison with the nonabused (NA) boys, the sexually abused boys were significantly more likely to demonstrate sudden emotional and behavioral changes, frequent stomachaches, more knowledge about sex and sexual activities than expected for age, unusual agressiveness toward playmate or toy's private parts, crying easily, difficulty getting to sleep, and a change to poor school performance. The internal reliability of the SASA was determined to be .83 and scoring of an abbreviated 12-item scale demonstrated a sensitivity of 90.9% and a specificity of 88.5%.Conclusions: The findings suggest that Structured Interview of Symptoms Associated with Sexual Abuse (SASA) is an effective tool which may help in the comprehensive assessment of boys who may have been sexually abused.  相似文献   
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