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171.
In Western societies scientists are increasingly expected to seek media exposure and cooperate with industry. Little attention
has been given to the way such expectations affect the role of scientific experts in society. To investigate scientists’ own
perspectives on these issues eight exploratory, in-depth interviews were conducted in Denmark with reputable nutrition scientists.
Additionally, eight interviews were held with ‘key informants’ from the field of nutrition policy. It was found that nutrition
scientists experience two dilemmas: first, between their aspiration to make a collective impact on public health and the powerful
incentives of each to appear frequently in the media with new messages; second, between their need to cooperate with the food
industry for financial reasons and their fear that this may compromise their independence and scientific integrity. It is
argued that the dilemmas identified in this study should be dealt with openly by the relevant groups of scientists. 相似文献
172.
Theo Araujo Anke Wonneberger Peter Neijens Claes de Vreese 《Communication methods and measures》2017,11(3):173-190
Given the importance of survey measures of online media use for communication research, it is crucial to assess and improve their quality, in particular because the increasingly fragmented and ubiquitous usage of internet complicates the accuracy of self-reported measures. This study contributes to the discussion regarding the accuracy of self-reported internet use by presenting relevant factors potentially affecting biases of self-reports and testing survey design strategies to improve accuracy. Combining automatic tracking data and survey data from the same participants (N = 690) confirmed low levels of accuracy and tendencies of over-reporting. The analysis revealed biases due to a range of factors associated with the intensity of (actual) internet usage, propensity to multitask, day of reference, and the usage of mobile devices. An anchoring technique could not be proved to reduce inaccuracies of reporting behavior. Several recommendations for research practice follow from these findings. 相似文献
173.
174.
Kenneth Tobin Leonie Rennie Grady Venville Hye-Eun Chu Peter Fensham James Gallagher Reinders Duit Wolfgang Graeber Ed van den Berg Brian Hand Stephen Ritchie Justin Dillon 《Cultural Studies of Science Education》2011,6(3):783-793
For almost a half century David F. Treagust has been an exemplary science educator who has contributed through his dedication and commitments to students, curriculum development and collaboration with teachers, and cutting edge research in science education that has impacted the field globally, nationally and locally. A hallmark of his outstanding career is his collaborative style that inspires others to produce their best work. 相似文献
175.
176.
177.
Many scientists and coaches are interested in mechanical power produced during cycling, and use Schoberer Rad Me\technik (SRM)
bicycle power cranks to obtain this data. However, it has been expensive and difficult to calibrate SRM cranks, causing much
of the collected data to be unreliable. We present a static method, derived from first principles, for obtaining a calibration
factor for SRM cranks.
A known mass and lever arm (chainring of a known diameter) are used to apply a known torque load to the instrument in four
positions, and the output frequencies are used to calculate the calibration factor in Hz/Nm. The reproducibility of this method
is ±0.01 Hz/Nm, which is acceptable for the application of the instrument, which is measurement of mechanical power application
by cyclists at the crank.
The method is reliable, inexpensive, and easy to set up, and will allow higher confidence in data collected using SRM power
cranks. We recommend calibration of the power meter once every six months because of the measured drift of the calibration
factor over time. 相似文献
178.
Peter K. Dunn 《Teaching Statistics》2005,27(2):37-41
Rolling dice and tossing coins can still be used to teach probability even if students know (or think they know) what happens in these experiments. This article considers many simple variations of these experiments which are interesting, potentially enjoyable and challenging. Using these variations can cause students (and teachers) to think again about the statistical issues involved – and learn in the process. 相似文献
179.
A series of studies of shuttlebox-avoidance learning in the gerbil evaluated the efficacy of an exteroceptive feedback stimulus (FS). Experiment 1 assessed the relative effectiveness of a FS at 30- and 90-sec intertriai intervals (ITIs), and found that the FS and warning signal termination contingencies were additive sources of avoidance reinforcement; i.e., they produced “supernormal acquisition” at the short ITI, but not at the 90-sec ITI. The effectiveness of a FS at the 30-sec ITI was further explored in Experiments 2 and 3, in which FS duration was varied in delayed and trace avoidance conditioning, respectively. In both studies, a FS facilitated acquisition but FS duration was not a critical determinant of performance. These results were interpreted in terms of an expectancy account of the informational value of a FS, and the problem of experimentally distinguishing between cognitive and inhibition-of-fear accounts of avoidance learning was discussed. 相似文献
180.
Peter Riley Bahr 《Research in higher education》2007,48(6):695-725
Prior research has established that the depth and breadth of remedial need in basic skills (math and English) exhibited by
a student at college entry are strongly and negatively associated with the likelihood of achieving college-level competency
in those subjects (i.e., successful remediation). This well-documented finding is built upon a body of work employing either
simple bivariate analyses or regression analyses that assume additive effects. Yet, there are reasons to suspect that multiple
basic skill deficiencies, rather than exhibiting additive effects alone, may exhibit a negative multiplicative interaction
effect on the likelihood of successful remediation. In this research, I test the hypothesis that the negative effect of math
deficiency increases in magnitude with decreasing English competency. Although the data support this hypothesis, I find that
this interaction does not have substantive importance in the face of the powerful direct effect of math deficiency on the
likelihood of successful remediation in math.
Direct all correspondence to the author at the Department of Sociology, Wayne State University, Detroit, Michigan, 48202 (peter.bahr@wayne.edu).
I am indebted to Tim Brown, Willard Hom, Myrna Huffman, Tom Nobert, Mary Kay Patton, and Patrick Perry of the Chancellor’s
Office of California Community Colleges for their assistance with the data employed in this study, and to Dr. John C. Smart
and the anonymous referees of Research in Higher Education for their recommendations concerning improving this work. 相似文献