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901.
Over the past two years, Florida State University's Science Education Program and Sabal Palm Elementary have collaborated to develop a PPS. The formation of the Sabal Palm PPS was not based upon a predetermined design nor has one group served as an authority to direct how the PPS ought to operate. The success of this model relies on PPS participants working collaboratively to establish goals and plans for actions to be taken to support teacher-learning. The Sabal Palm PPS continues to evolve as dynamic model for creating a center for teacher and student learning. The purpose of this paper is to discuss our involvement in the formation a PPS and implications for enhancing teacher education programs. Specializations: professional practice school development, teacher research, primary science education Specializations: environmental science, primary science education.  相似文献   
902.
903.
Reinstatement after counterconditioning was examined in three experiments with rats. The rats received CS-shock pairings in Phase 1 and then CS-food pairings in Phase 2. When unsignaled shock was presented after appetitive conditioning, fear performance to the CS replaced food performance. This reinstatement effect depended on initial pairings of the CS and shock in Phase 1. It also depended on shock exposure occurring in the test context. The results parallel previous data obtained after extinction. Counterconditioning and extinction yield several parallel effects (spontaneous recovery, renewal, and now reinstatement) which suggest that Phase 2 does not destroy the learning acquired in Phase 1.  相似文献   
904.
A causal model for understanding the complex interplay between student‐reported teacher behaviors, student self‐systems, and student engagement was tested. One hundred seventeen African American students in grades 1 through 12 completed a comprehensive questionnaire regarding teacher context, self, and engagement variables. A series of hierarchical regression analyses were conducted to test the hypothesized mediation models and to construct a path model. Most hypotheses were supported. Student self‐system variables (perceived competency and autonomy) mediated relations between teacher context (structure and autonomy support), and engagement. Contrary to predictions, however, teacher involvement exerted a strong and direct effect on student engagement even when controlling for grade level and self‐system variables. Given existing research showing that African American students are at risk for low teacher involvement and that engagement is critical for academic success, research and intervention strategies are urgently needed to promote teacher involvement with these students. © 2002 Wiley Periodicals, Inc.  相似文献   
905.
OBJECTIVE: This study seeks to: (1) assess the relationship between identified prenatal substance use and the risk of subsequent maltreatment allegations among families involved with child protective services; and (2) compare the types of safety threats encountered by children whose parents had substance-exposed infant (SEI) allegations to the types of safety threats faced by children whose parents had other types of allegations. METHOD: Survey data from a probability sample of parents were linked to state administrative data over a 33-month time frame. Cox regression models were conducted to assess the relative risk of subsequent allegations associated with parents whose child welfare case opened following an SEI allegation (the SEI group) compared to parents whose case opened following other types of allegations. RESULTS: The likelihood of subsequent allegations is greater among parents in the SEI group. However, the increased risk stems almost entirely from subsequent SEI-related allegations. Parents in the SEI group are not more likely to incur other types of allegations such as physical abuse or lack of supervision. CONCLUSIONS: An increased risk of subsequent maltreatment has been used to justify opening child protective cases on the basis of an SEI allegation alone. By looking closely at the types of subsequent allegations as well as the incidence of subsequent allegations, this research helps to clarify the maltreatment risks associated with SEI cases.  相似文献   
906.
907.
Information loss occurs when continuous data are grouped in discrete intervals. After calculating the squared correlation coefficients between continuous data and corresponding grouped data for four population distributions, the effects of population distribution, number of intervals, and interval width on information loss and recover), were examined.  相似文献   
908.
909.
In business research situations it is often of interest to examine the differences in the responses in repeated measurements of the same subjects or from among matched or paired subjects. A simple and useful procedure for comparing differences between proportions in two related samples was devised by McNemar (1947) nearly 60 years ago. Although the technique has enjoyed widespread usage in both behavioral and medical research, it has unfortunately not received proper attention in marketing, advertising, consumer research, public relations, operations management, or organizational behavior endeavors—disciplines wherein it is particularly desirable to evaluate the significance of changes in attitudes, opinions, or beliefs regarding some campaign or strategy. Perhaps the major reason for this obscurity is simply a general lack of awareness as to its value and practical power. The McNemar test is generally not currently being taught to business statistics students. It is the purpose of this article to demonstrate the usefulness and applicability of the McNemar procedure to these aforementioned disciplines so that it may be more appropriately employed as an important confirmatory data analysis tool within the basic business statistics curriculum.  相似文献   
910.
Two experiments with rat subjects examined whether a saccharin taste could potentiate the conditioning of an aversion to a salty taste when the two stimuli were presented together prior to lithium-induced illness. In Experiment 1, a 0.1% (w/v) saccharin solution potentiated conditioning of a very dilute (0.03%) NaCl solution, but had no demonstrable effect on two stronger NaCl solutions (0.6% and 1.2%). In Experiment 2, the 0.1% saccharin solution again potentiated the 0.03% NaCl target, but weaker and stronger saccharin concentrations (0.033% and 0.3%) did not. The ability of a taste to potentiate a secondtaste is not consistent with theories that assume that potentiation is unique to compounds composed of tastes and other, functionally different, nontaste cues. Potentiation may occur when the target stimulus is weakly conditionable on its own and when the particular combination of target and potentiator facilitates perceptual integration of the compound.  相似文献   
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