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61.
Honeybees foraged from six locations, each of which was baited with sugar solution prior to each experimental trial. Under a variety of conditions, bees exhibited a small but reliable tendency to avoid revisits to locations that they had visited earlier during the experimental trial. These results replicate those of Brown and Demas (1994), who concluded that bees use working memory to discriminate previously visited locations from those not yet visited. The present experiments included procedures that allowed alternatives to this explanation to be more completely ruled out. The extent of spatial working memory performance exhibited by honeybees in these experiments appears to be limited by a process other than working memory capacity, perhaps the ability of bees to discriminate among several locations in close proximity to one another.  相似文献   
62.
Pregnant HIV-positive women have unique education needs during the perinatal period. HIV-positive women need information regarding the differences in recommended care they can expect to experience both for themselves and their newborn. Differences in recommended care are related to minimizing transmission of the HIV virus. This article discusses the unique educational content needs of HIV-positive pregnant women. Providing women with appropriate information about what their labor and delivery experiences will entail can help them make decisions and promote a positive birth experience.  相似文献   
63.
Businesses and educational institutions use satellite technology to transmit information for a number of purposes, including training. This study assessed the effectiveness of a satellite training program for achieving various learning requirements ranging from recognition and recall of information to the performance of a specific job procedure. This study also compared satellite training with traditional classroom training for two courses in which the same material was taught using both media. Results showed that learning occurred using the satellite medium and that there were slight but statistically significant differences between satellite and classroom instruction for learning job-related skills.Kristen M. Williams is a senior member of AIR's research staff specializing in training research and evaluation. The research reported here was conducted under Contract Number 104230-88-D-1811, Task Order Number 10430-92-D-1296 with the United States Postal Service. Opinions and conclusions presented do not necessarily reflect those of the U.S. Postal Service.  相似文献   
64.
This article examines how parental education level moderates the genetic and environmental contributions to variation in verbal IQ. Data are from 1909 non-Hispanic Whites and African American sibling pairs from the National Longitudinal Study of Adolescent Health, which obtained nationally-based samples of identical (MZ) twins, fraternal (DZ) twins, full and half siblings, cousins (in the same household), and biologically unrelated siblings. In the whole sample, the variance estimate for heritability (h2 = .57, SE = .08) was greater than that for shared environment (c2 = .13, SE = .04). Both heritability and the shared environmental estimate were moderated, however, by level of parental education. Specifically, among more highly educated families, the average h2 = .74 (SE = .10) and the average c2 = .00 (SE = .05). Conversely, among less well-educated families, heritability decreased and shared environmental influences increased, yielding similar proportions of variance explained by genetic and environmental factors, average h2 = .26 (SE = .15), and average c2 = .23 (SE = .07).  相似文献   
65.
A new economic model for the analysis of scholarly publishing – journal publishing in particular – is proposed that draws on club theory. The standard approach builds on market failure in the private production (by research scholars) of a public good (new scholarly knowledge). In this model, publishing is communication, as the dissemination of information. But a club model views publishing differently: namely as group formation, where members form groups in order to confer externalities on each other, subject to congestion. A journal is a self-constituted group, endeavouring to create new knowledge. In this sense, a journal is a club. The knowledge club model of a journal seeks to balance the positive externalities of a shared resource (readers, citations, referees) against the negative externalities of crowding (decreased prospect of publishing in that journal). A new economic model of a journal as a knowledge club is elaborated. We suggest some consequences for the management of journals and financial models that might be developed to support them.  相似文献   
66.
This paper reflects upon student teachers' conceptions of inter-community relations and the preparation they receive to address issues of diversity and mutual understanding. The study in Northern Ireland is set against a backdrop of political, social and educational change, where a shared, peaceful future appears possible. Student teachers at a Catholic institution and a predominantly Protestant institution indicated a willingness to engage with issues concerning diversity and inter-community relations, despite having a limited knowledge of the concepts. However they also demonstrated clear views about the relevance and value of the preparation they received. The findings are evaluated using multicultural theory.  相似文献   
67.
Materials science, which entails the practices of selecting, testing, and characterizing materials, is an important discipline within the study of matter. This paper examines how third grade students’ materials science performance changes over the course of instruction based on an engineering design challenge. We conducted a case study of nine students who participated in engineering design-based science instruction with the goal of constructing a stable, quiet, thermally comfortable model house. The learning outcome of materials science practices was assessed by clinical interviews conducted before and after the instruction, and the learning process was assessed by students’ workbooks completed during the instruction. The interviews included two materials selection tasks for designing a sturdy stepstool and an insulated pet habitat. Results indicate that: (1) students significantly improved on both materials selection tasks, (2) their gains were significantly positively associated with the degree of completion of their workbooks, and (3) students who were highly engaged with the workbook’s reflective record-keeping tasks showed the greatest improvement on the interviews. These findings suggest the important role workbooks can play in facilitating elementary students’ learning of science through authentic activity such as engineering design.  相似文献   
68.
Early childhood curricula should be authentic and child-centered, however, many teachers still rely on direct instruction lessons. To better define how an integrated curriculum meets the needs of students, this study examined teacher talk and actions during instructional activities with first and second graders under two conditions: (1) subject-integrated social studies lessons of an integrated curriculum unit (experimental condition); and (2) single subject-focused mathematics lessons of a traditional separate subject curriculum (control condition). The mixed-methods study sought to define and compare characteristics of both curriculum approaches. Fourteen hours of observations were collected in each setting. In the integrated curriculum setting, the teacher was a facilitator of teamwork, offering choices, and giving praise; students made choices, decisions, and worked collaboratively. In the traditional setting, the teacher delivered direct instruction and controlled behavior; students followed directions, recalled knowledge, and worked individually. Less teacher energy was expended for behavior management in the integrated curriculum setting, indicating intrinsic motivation of students. Implementation of integrated curricula is recommended because of the student-centered focus that results in greater motivation, ownership, and teamwork, along with deeper knowledge connections. Because many factors hinder implementation, teachers need support when first teaching with this approach.  相似文献   
69.
Peer victimization (PV) has been associated with a number of negative psychological sequelae. Few studies, however, have examined the relationship between PV and the symptomatology of post‐traumatic stress disorder, and no studies to date have examined this relationship in a rural sample. Adapted versions of the SEQ‐SR and the TSCC were used to assess the relationship between PV and post‐traumatic stress symptomatology in a sample of 244 rural youths (ages 10–14) in two school districts in a south‐central area of the United States. In addition to a positive relationship between PV and post‐traumatic stress symptomatology, the results indicated relatively high rates of adult presence and peer bystanding during PV experiences. Limitations and implications for practice are discussed. © 2010 Wiley Periodicals, Inc.  相似文献   
70.
The aims of this study were to determine if there are significant kinematic changes in running pattern after intense interval workouts, whether duration of recovery affects running kinematics, and whether changes in running economy are related to changes in running kinematics. Seven highly trained male endurance runners (VO 2max = 72.3 +/- 3.3 ml kg -1 min -1 ; mean +/- s) performed three interval running workouts of 10 X 400 m at a speed of 5.94 +/- 0.19 m s -1 (356 +/- 11.2 m min -1 ) with a minimum of 4 days recovery between runs. Recovery of 60, 120 or 180 s between each 400 m repetition was assigned at random. Before and after each workout, running economy and several kinematic variables were measured at speeds of 3.33 and 4.47 m s -1 (200 and 268 m min -1 ). Speed was found to have a significant effect on shank angle, knee velocity and stride length (P ? 0.05). Correlations between changes pre- and post-test for VO 2 (ml kg -1 min -1 ) and several kinematic variables were not significant (P > 0.05) at both speeds. In general, duration of recovery was not found to adversely affect running economy or the kinematic variables assessed, possibly because of intra-individual adaptations to fatigue.  相似文献   
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