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151.
The present paper summarizes international and national research findings on the general and differential effectiveness of pedagogical work in early childhood education and care settings, evaluations of pilot projects on compensatory preschool education as well programs to support individual learning abilities. Based on these findings, the following conclusions are drawn: First, attending early childhood education and care settings at an early age (after the age of three) has a positive influence on the development of academic competences. Second, the effectiveness of these settings depends on the instructional quality, which could be considerably improved in Germany. Third, pilot projects on programs to support individual learning abilities could show that compensatory effects for disadvantaged groups of children exist, especially when they are interlinked with stimulating conditions in the family and at school. Fourth, effective training programs exist that can be implemented in early childhood education and care. However, a number of challenges need to be met before they can be successfully implemented. 相似文献
152.
Marcus Wagner 《Research Policy》2011,40(9):1217-1225
Innovation in high technology industries poses considerable challenges, frequently forcing firms to consider using acquisitions as a means of sourcing technology. This paper investigates such behaviour in a major high technology sector, namely the semiconductor industry. The paper focuses on differential effects of technology-related versus nontechnological acquisitions on exploratory and exploitative research and innovation. Most importantly, it confirms the important role of technology-related acquisitions for exploratory innovation. 相似文献
153.
Giraud G Pethig R Schulze H Henihan G Terry JG Menachery A Ciani I Corrigan D Campbell CJ Mount AR Ghazal P Walton AJ Crain J Bachmann TT 《Biomicrofluidics》2011,5(2):24116
The manipulation of ribosomal RNA (rRNA) extracted from E. coli cells by dielectrophoresis (DEP) has been demonstrated over the range of 3 kHz-50 MHz using interdigitated microelectrodes. Quantitative measurement using total internal reflection fluorescence microscopy of the time dependent collection indicated a positive DEP response characterized by a plateau between 3 kHz and 1 MHz followed by a decrease in response at higher frequencies. Negative DEP was observed above 9 MHz. The positive DEP response below 1 MHz is described by the Clausius-Mossotti model and corresponds to an induced dipole moment of 3300 D with a polarizability of 7.8×10(-32) F m(2). The negative DEP response above 9 MHz indicates that the rRNA molecules exhibit a net moment of -250 D, to give an effective permittivity value of 78.5 ε(0), close to that of the aqueous suspending medium, and a relatively small surface conductance value of ~0.1 nS. This suggests that our rRNA samples have a fairly open structure accessible to the surrounding water molecules, with counterions strongly bound to the charged phosphate groups in the rRNA backbone. These results are the first demonstration of DEP for fast capture and release of rRNA units, opening new opportunities for rRNA-based biosensing devices. 相似文献
154.
155.
156.
Tuition at private colleges in the United States for the academic year 1982–1983 were statistically very closely related to quality characteristics associated with those colleges. Reduced form hedonic regressions reveal the equilibrium marginal tuition revenue estimates for over twenty important measures of quality, including faculty-student ratios, library size, and the percentage of the faculty holding Ph.D. degrees. These findings show that private college tuition responds in economically sensible ways to changes in public tuition, and changes in the quantity and quality of the faculties, facilities, and student bodies at private colleges. 相似文献
157.
ABSTRACTScholars writing on agency argue that normally, individuals who experience social structures as comfortable will tend to want to reproduce them while those who experience these structures as oppressive will want to change them. This is a bleak outlook because it suggests that those in positions of power and influence are less likely to seek to overhaul the very system of rewards and punishments that benefits them. However, there are exceptions to this pattern: instances where those who experience the structures as comfortable, nevertheless, work at transforming them. This article introduces an alternative perspective to current transformation discourses by seeking to understand why such exceptions exist. It argues that critical engagement is an important dimension of such transformation, and examines how it interacts with reflexivity to shape individual choices and reformulate interest. Drawing on a hermeneutic phenomenological analysis of in-depth interviews with 10 academics who have been identified as agents of change at one university in South Africa, we reveal how individuals are able to shift their understanding of what is or is not in their interest in a context where raced, gendered and classed interests are deeply embedded in the fabric of the society. In such contexts, reflexivity and critical personal engagement with one’s context can lead to a shift in interest and then consciousness as the individual comes to see and experience things from a different vantage point, opening up the possibility for a changed relationship with the social structure and its constraints and determining influence. 相似文献
158.
Michael Windle Carol Miller-Tutzauer Grace M. Barnes John Welte 《Child development》1991,62(1):179-189
Adolescent perceptions of help-seeking social resources (e.g., parents, friends, school counselor, clergyman) they would utilize if they were having substance abuse difficulties were investigated for samples of early and middle adolescents. 8 different perceived help-seeking categories were identified, and intergroup comparisons were made with regard to gender and ethnic/racial group and with regard to alcohol consumption, substance-related problems, and school misconduct. 2 perceived help-seeking categories had the highest levels of problem behaviors. The first category consisted of adolescents who identified friends as the only social resource they would utilize if they were having substance abuse problems. The second category, referred to as social isolates, indicated that they would not utilize any social resource if they were having substance abuse problems. There were approximately twice as many male social isolates as female social isolates, and blacks and Hispanics were highly overrepresented in the social isolate category. 相似文献
159.
OBJECTIVE: It has often been hypothesized that because of a lack of early satisfactory attachments, sex offenders grow up unable to form relationships with adults, which makes them susceptible to pursue intimacy in maladaptive ways. This research aims to empirically examine the parental bonding patterns for a group of sex offenders, comparing child molesters and rapists. METHOD: Seventy-six men convicted of a sexual offense (57 child molesters and 19 rapists) completed the parental bonding instrument (PBI), and were assessed by means of a semi-structured clinical interview. RESULTS: Affectionless control style of parental bonding was highly prevalent amongst the sex offenders. There was some suggestion that low parental care was associated with childhood abuse and disturbances, particularly for child molesters. High overprotection in mothers was linked with parental separation and sex play with male peers in childhood. CONCLUSIONS: There is a need to replicate the study with non-sexual offenders as a comparison group, and to establish whether the PBI provides a useful adjunct to studies of adult romantic attachment in sex offenders. 相似文献
160.
The construction of a building may change the microclimate in the vicinity, and planning indicators in a master plan may directly affect the outdoor physical environmental quality in residential areas. An inappropriate plan for a site may accelerate wind and intensify vortexes over places on the pedestrian levels, which leads to an adverse outdoor environment. Therefore, the design of a cluster of buildings should not focus only on the buildings but also provide a good outdoor environment around the buildings. To tackle the problem of inadequate wind environment, the relationship between the building’s floor area ratio and height was identified in this study as the main planning indicator to be examined on its effects on the outdoor wind environment. A computational fluid dynamics (CFD) model was hence developed to simulate the wind conditions generated by some typical site layouts with different values for planning indicators under relevant weather conditions, which were typical of those in Hangzhou, China. The simulated wind conditions are assessed using the wind speed ratio over the whole area of the building cluster at the pedestrian level. The effects on the local wind condition due to the varying of the planning indicators are discussed whilst considering the potential construction costs. The indicators resulting in better external conditions are highlighted in the conclusion as the recommendation which could be used as a rule of thumb by architects and planners at the master planning stage. The study disproves the common belief in the practice that a lower floor area ratio means fewer buildings and therefore greater external comfort. In fact, the higher the building, the greater the outdoor comfort wind zone for pedestrians. However, the increment in comfort area is limited to buildings extending from 25 to 30 levels. 相似文献