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81.
82.
Edward Barrow 《Learned Publishing》1998,11(4):259-263
Rightsholders' groups have given CLA approval to develop sector-by-sector licences for the digitisation of existing print material. The first two licences, for pharmaceutical regulatory submissions and for higher education, are approaching completion. Rightsholders will be asked to opt-in to each of them and to determine applicable fees for each of their publications. 相似文献
83.
The short-term memory for sounds of the bottlenosed dolphin was tested using symbolic, identity, and probe forms of the delayed matching-to-sample (DMS) task. The forms differed in the number (one or two) or nature (symbolic or identity matches of sample sounds) of postdelay test stimuli available as memory retrieval cues. Although symbolic DMS was difficult to learn, the final performance level was approximately equal to that for identity or probe DMS. On all tasks, the dolphin’s responses were above 80% correct through to delays of 90 sec and, in some cases, through to delays of 180 and 240 sec, the “limits” being governed mainly by the dolphin’s reluctance to continue being tested at long delays. Encoding of sample stimuli into their learned symbolic representation was hypothesized to have reduced symbolic DMS to a recognition memory task, resulting in the observed equivalence of performance with the other two recognition memory tasks. The probe DMS results, unlike those for identity or symbolic DMS, showed no significant proactive interference effects from samples of prior trials. Instead, proactive interference was traceable to the probe value of the prior trial. Overall, the auditory DMS data for the dolphin were functionally similar to results reported for monkeys tested on symbolic, identity, and probe visual DMS tasks. 相似文献
84.
85.
The “Advances in Library Data and Access” column examines technological advances internal and external to libraries. The focus is on how library data is created and used. The strength of the column is its broad, international focus and contributors are encouraged to explore issues and recent advances in information technology relevant to their geographical region, as well as the larger, global audience. Interested authors are invited to submit proposals and articles to the column editor at moulaisonhe@missouri.edu. Please include “IILR Submission” in the subject line of the e-mail. 相似文献
86.
Greg Atkinson Richard Davison Asker Jeukendrup Louis Passfield 《Journal of sports sciences》2013,31(9):767-787
Abstract In this holistic review of cycling science, the objectives are: (1) to identify the various human and environmental factors that influence cycling power output and velocity; (2) to discuss, with the aid of a schematic model, the often complex interrelationships between these factors; and (3) to suggest future directions for research to help clarify how cycling performance can be optimized, given different race disciplines, environments and riders. Most successful cyclists, irrespective of the race discipline, have a high maximal aerobic power output measured from an incremental test, and an ability to work at relatively high power outputs for long periods. The relationship between these characteristics and inherent physiological factors such as muscle capilliarization and muscle fibre type is complicated by inter-individual differences in selecting cadence for different race conditions. More research is needed on high-class professional riders, since they probably represent the pinnacle of natural selection for, and physiological adaptation to, endurance exercise. Recent advances in mathematical modelling and bicycle-mounted strain gauges, which can measure power directly in races, are starting to help unravel the interrelationships between the various resistive forces on the bicycle (e.g. air and rolling resistance, gravity). Interventions on rider position to optimize aerodynamics should also consider the impact on power output of the rider. All-terrain bicycle (ATB) racing is a neglected discipline in terms of the characterization of power outputs in race conditions and the modelling of the effects of the different design of bicycle frame and components on the magnitude of resistive forces. A direct application of mathematical models of cycling velocity has been in identifying optimal pacing strategies for different race conditions. Such data should, nevertheless, be considered alongside physiological optimization of power output in a race. An even distribution of power output is both physiologically and biophysically optimal for longer ( >4km) time-trials held in conditions of unvarying wind and gradient. For shorter races (e.g. a 1km time-trial), an‘all out’ effort from the start is advised to‘save’ time during the initial phase that contributes most to total race time and to optimize the contribution of kinetic energy to race velocity. From a biophysical standpoint, the optimum pacing strategy for road time-trials may involve increasing power in headwinds and uphill sections and decreasing power in tailwinds and when travelling downhill. More research, using models and direct power measurement, is needed to elucidate fully how much such a pacing strategy might save time in a real race and how much a variable power output can be tolerated by a rider. The cyclist's diet is a multifactorial issue in itself and many researchers have tried to examine aspects of cycling nutrition (e.g. timing, amount, composition) in isolation. Only recently have researchers attempted to analyse interrelationships between dietary factors (e.g. the link between pre-race and in-race dietary effects on performance). The thermal environment is a mediating factor in choice of diet, since there may be competing interests of replacing lost fluid and depleted glycogen during and after a race. Given the prevalence of stage racing in professional cycling, more research into the influence of nutrition on repeated bouts of exercise performance and training is required. 相似文献
87.
88.
Laursen PB Knez WL Shing CM Langill RH Rhodes EC Jenkins DG 《Journal of sports sciences》2005,23(10):1111-1120
The aim of the present study was to examine the relationship between the performance heart rate during an ultra-endurance triathlon and the heart rate corresponding to several demarcation points measured during laboratory-based progressive cycle ergometry and treadmill running. Less than one month before an ultra-endurance triathlon, 21 well-trained ultra-endurance triathletes (mean +/- s: age 35 +/- 6 years, height 1.77 +/- 0.05 m, mass 74.0 +/- 6.9 kg, = 4.75 +/- 0.42 l x min(-1)) performed progressive exercise tests of cycle ergometry and treadmill running for the determination of peak oxygen uptake (VO2peak), heart rate corresponding to the first and second ventilatory thresholds, as well as the heart rate deflection point. Portable telemetry units recorded heart rate at 60 s increments throughout the ultra-endurance triathlon. Heart rate during the cycle and run phases of the ultra-endurance triathlon (148 +/- 9 and 143 +/- 13 beats x min(-1) respectively) were significantly (P < 0.05) less than the second ventilatory thresholds (160 +/- 13 and 165 +/- 14 beats x min(-1) respectively) and heart rate deflection points (170 +/- 13 and 179 +/- 9 beats x min(-1) respectively). However, mean heart rate during the cycle and run phases of the ultra-endurance triathlon were significantly related to (r = 0.76 and 0.66; P < 0.01), and not significantly different from, the first ventilatory thresholds (146 +/- 12 and 148 +/- 15 beats x min(-1) respectively). Furthermore, the difference between heart rate during the cycle phase of the ultra-endurance triathlon and heart rate at the first ventilatory threshold was related to marathon run time (r = 0.61; P < 0.01) and overall ultra-endurance triathlon time (r = 0.45; P < 0.05). The results suggest that triathletes perform the cycle and run phases of the ultra-endurance triathlon at an exercise intensity near their first ventilatory threshold. 相似文献
89.
Edward P. Hyde P.W. Cobb H.M. Johnson W. Weniger 《Journal of The Franklin Institute》1920,189(3):331-369
90.
Effects of student versus staff tutoring on student learning in a problem-based, health sciences curriculum were studied. Academic achievement of 334 tutorial groups guided by staff tutors was compared with achievement of 400 groups guided by student tutors. In addition, students rated their tutor's performance on four behaviors considered critical to facilitating student learning. Overall, students guided by a staff tutor achieved somewhat better. In terms of practical significance, the difference was, however, fairly small. Staff tutors were rated as more knowledgeable and their contributions as more relevant. In addition, they asked stimulating questions to a larger extent. However, an interaction effect was found between the ratings and the year of study: Peer tutors displayed the supportive behaviors more extensively in the first year, whereas staff tutors' ratings were higher as the curriculum advanced. These results were interpreted in terms of the cognitive congruence framework.Parts of this article have been presented to the Annual Meeting of the American Educational Research Association, Atlanta, GA, April, 1993. 相似文献