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151.
Brit Toven-Lindsey Marc Levis-Fitzgerald Paul H. Barber Tama Hasson 《CBE life sciences education》2015,14(2)
The 6-yr degree-completion rate of undergraduate science, technology, engineering, and mathematics (STEM) majors at U.S. colleges and universities is less than 40%. Persistence among women and underrepresented minorities (URMs), including African-American, Latino/a, Native American, and Pacific Islander students, is even more troubling, as these students leave STEM majors at significantly higher rates than their non-URM peers. This study utilizes a matched comparison group design to examine the academic achievement and persistence of students enrolled in the Program for Excellence in Education and Research in the Sciences (PEERS), an academic support program at the University of California, Los Angeles, for first- and second-year science majors from underrepresented backgrounds. Results indicate that PEERS students, on average, earned higher grades in most “gatekeeper” chemistry and math courses, had a higher cumulative grade point average, completed more science courses, and persisted in a science major at significantly higher rates than the comparison group. With its holistic approach focused on academics, counseling, creating a supportive community, and exposure to research, the PEERS program serves as an excellent model for universities interested in and committed to improving persistence of underrepresented science majors and closing the achievement gap. 相似文献
152.
Kozeracki CA Carey MF Colicelli J Levis-Fitzgerald M Grossel M 《CBE life sciences education》2006,5(4):340-347
UCLA's Howard Hughes Undergraduate Research Program (HHURP), a collaboration between the College of Letters and Science and the School of Medicine, trains a group of highly motivated undergraduates through mentored research enhanced by a rigorous seminar course. The course is centered on the presentation and critical analysis of scientific journal articles as well as the students' own research. This article describes the components and objectives of the HHURP and discusses the results of three program assessments: annual student evaluations, interviews with UCLA professors who served as research advisors for HHURP scholars, and a survey of program alumni. Students indicate that the program increased their ability to read and present primary scientific research and to present their own research and enhanced their research experience at UCLA. After graduating, they find their involvement in the HHURP helped them in securing admission to the graduate program of their choice and provided them with an advantage over their peers in the interactive seminars that are the foundation of graduate education. On the basis of the assessment of the program from 1998–1999 to 2004–2005, we conclude that an intensive literature-based training program increases student confidence and scientific literacy during their undergraduate years and facilitates their transition to postgraduate study. 相似文献
153.
Association between 11beta-hydroxysteroid dehydrogenase type 1 gene polymorphisms and metabolic syndrome in Bosnian population 总被引:1,自引:0,他引:1
Dujic T Bego T Mlinar B Semiz S Malenica M Prnjavorac B Ostanek B Marc J Causevic A 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2012,22(1):76-85
Introduction:
The enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) catalyzes the conversion of the hormonally inactive cortisone to active cortisol, thus facilitating glucocorticoid receptor activation in target tissues. Increased expression of 11β-HSD1 in adipose tissue has been associated with obesity and insulin resistance. In this study, we investigated the association of two 11β-HSD1 gene (HSD11B1) polymorphisms with the metabolic syndrome (MetS) and its characteristics in the Bosnian population.Materials and methods:
The study included 86 participants: 43 patients diagnosed with MetS and 43 healthy controls. Subjects were genotyped for two HSD11B1 gene polymorphisms: rs846910: G>A and rs45487298: insA, by the high resolution melting curve analysis. Genotype distribution and an influence of genotypes on clinical and biochemical parameters were assessed.Results:
There was no significant difference in the mutated allele frequencies for the two HSD11B1 gene polymorphisms between MetS patients and controls. In MetS patients, no significant associations between disease-associated traits and rs45487298: insA were found. Regarding rs846910: G>A variant, heterozygous patients (G/A) had significantly lower systolic (P = 0.017) and diastolic blood pressure (P = 0.015), lower HOMA-IR index (P = 0.011) and higher LDL-cholesterol levels (P = 0.049), compared to the wild-type homozygotes. In the control group, rs45487298: insA polymorphism was associated with lower fasting plasma insulin levels (P = 0.041), lower homeostasis model assessment insulin resistance (HOMA-IR) index (P = 0.041) and lower diastolic blood pressure (P = 0.048). Significant differences between rs846910: G>A genotypes in controls were not detected. Haplotype analysis confirmed the association of rs45487298: insA with markers of insulin resistance in the control subjects.Conclusions:
Our results indicate that a common rs45487298: insA polymorphism in HSD11B1 gene may have a protective effect against insulin resistance. 相似文献154.
155.
Psychology has penetrated many domains of society and its vocabulary and discourse has become part of our everyday conversations. It not only carries with it the promise that it will deliver insights into human behaviour, but it is also believed that it can address many of the problems human beings are confronted with. As a discipline it thrives in the present climate of performativity, where more attention is given to means than to ends. The article observes first that for education and thus for educational research, though psychology's approach can be valuable, other theoretical stances are also necessary. It then analyses why psychology may be attractive nowadays in the educational field and identifies its prestige in academia, partly arising from its professionalization, but above all the use of a particular method and the focus on certain contents. This has historical antecedents, and so some illustrations are given of previous developments, paying attention as well to the controversies in which educational psychology has been involved in the past, as well as to the need of biographical research, which warns us to be careful with generalizations. It is argued that a more balanced approach (invoking the particularities of the situation as well as a broader concept of practical rationality) is required for the study of education and that educational researchers therefore should resist the tendency to see psychology as the default auxiliary science of education; instead they should reclaim their territory, do justice to the responsibility that is required and highlight the importance of understanding social practices to a large extent in terms of reasons and intentions. 相似文献
156.
This study analyzed the activity of expert table tennis players during a match, in reference to course of action theory (Theureau, 1992). Matches were videotaped, and the players' verbalizations as they viewed the tapes were collected a posteriori. The data was analyzed by (a) transcribing the players' actions and verbalizations, (b) decomposing their activity into elementary units of meaning, and (c) grouping the elementary units into larger sets. The results showed that the matches began with an inquiry into the specific features of the opponent's play. This was followed by reproducing the actions identified as effective during the inquiry. The results are discussed in relation to the role of training in expert performance. 相似文献
157.
Tourism is important for many rural territories in France, notably with respect to economic development. A growing element of such tourist activity concerns outdoor sports which rely heavily on a region’s natural resources and are centred predominantly on a series of entrepreneurs and small businesses. Given the importance of tourism to local economies, a fuller understanding of the nature and operational characteristics of these enterprises, and of their relationship with other local actors, is essential to ensure their future development. With this objective, this paper aims to explore and evaluate the emergence of ‘localised tourist systems’ and the adaptation of this concept to outdoor sports. By using a systems approach, emphasis is given to analysing the interplay between different actors in the public, private and associative sectors and the mutual benefits that derive from such collaboration. Using evidence from the region of Ardèche in south-east France, it is argued that outdoor sports entrepreneurs form part of a ‘localised outdoor sports tourist system’ which provides added-value to the activities of these enterprises and to local institutional actors and the means to create a competitive advantage for the region’s tourist development. Future research might usefully explore in more detail the relative strength of linkages between the different actors. 相似文献
158.
The aim of the present study was to determine the effect of post-exercise ingestion of a unique, high molecular weight glucose polymer solution, known to augment gastric emptying and post-exercise muscle glycogen re-synthesis, on performance during a subsequent bout of intense exercise. On three randomized visits, eight healthy men cycled to exhaustion at 73.0% (s = 1.3) maximal oxygen uptake (90 min, s = 15). Immediately after this, participants consumed a one-litre solution containing sugar-free flavoured water (control), 100 g of a low molecular weight glucose polymer or 100 g of a very high molecular weight glucose polymer, and rested on a bed for 2 h. After recovery, a 15-min time-trial was performed on a cycle ergometer, during which work output was determined. Post-exercise ingestion of the very high molecular weight glucose polymer solution resulted in faster and greater increases in blood glucose (P < 0.001) and serum insulin (P < 0.01) concentrations than the low molecular weight glucose polymer solution, and greater work output during the 15-min time-trial (164.1 kJ, s = 21.1) than both the sugar-free flavoured water (137.5 kJ, s = 24.2; P < 0.05) and the low molecular weight glucose polymer (149.4 kJ, s = 21.8; P < 0.05) solutions. These findings could be of practical importance for athletes wishing to optimize performance by facilitating rapid re-synthesis of the muscle glycogen store during recovery following prolonged sub-maximal exercise. 相似文献
159.
Quod MJ Martin DT Laursen PB Gardner AS Halson SL Marino FE Tate MP Mainwaring DE Gore CJ Hahn AG 《Journal of sports sciences》2008,26(14):1477-1487
The purpose of this study was to compare the effects of two practical precooling techniques (skin cooling vs. skin + core cooling) on cycling time trial performance in warm conditions. Six trained cyclists completed one maximal graded exercise test (VO2(peak) 71.4 +/- 3.2 ml x kg(-1) x min(-1)) and four approximately 40 min laboratory cycling time trials in a heat chamber (34.3 degrees C +/- 1.1 degrees C; 41.2% +/- 3.0% rh) using a fixed-power/variable-power format. Cyclists prepared for the time trial using three techniques administered in a randomised order prior to the warm-up: (1) no cooling (control), (2) cooling jacket for 40 min (jacket) or (3) 30-min water immersion followed by a cooling jacket application for 40 min (combined). Rectal temperature prior to the time trial was 37.8 degrees C +/- 0.1 degrees C in control, similar in jacket (37.8 degrees C +/- 0.3 degrees C) and lower in combined (37.1 degrees C +/- 0.2 degrees C, P < 0.01). Compared with the control trial, time trial performance was not different for jacket precooling (-16 +/- 36 s, -0.7%; P = 0.35) but was faster for combined precooling (-42 +/- 25 s, - .8%; P = 0.009). In conclusion, a practical combined precooling strategy that involves immersion in cool water followed by the use of a cooling jacket can produce decrease in rectal temperature that persist throughout a warm-up and improve laboratory cycling time trial performance in warm conditions. 相似文献
160.