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751.
Learning Environment Perceptions of European University Students   总被引:1,自引:0,他引:1  
This article describes a study of the experiences of 610 Dutch students and 241 European students who studied at least three months abroad within the framework of an international exchange program. The Dutch students went to a university in another European country and the foreign students went to a Dutch university. Using a new questionnaire called the Inventory of Perceived Study Environment (IPSE), students, perceptions of eight characteristics of the university learning environment were measured concerning the home university, the host university and the ideal learning environment. With this instrument, the learning environment can be described in terms analogous to the learning strategies performed. Large differences were found between the different countries in university learning environments, but students from different countries had strikingly similar opinions concerning their desired learning environment. There was a strong preference for activating instruction with a low threshold in teacher-student interaction and more room for student alternatives.  相似文献   
752.
The present study was designed to examine the question of whether developmental dyslexia in 12-year-old students at the beginning of secondary education in the Netherlands is confined to problems in the domain of reading and spelling or also is related to difficulties in other areas. In particular, hypotheses derived from theories on phonological processing, rapid automatized naming, working memory, and automatization of skills were tested. To overcome the definition and selection problems of many previous studies, we included in our study all students in the first year of secondary special education in a Dutch school district. Participants were classified as either dyslexic, garden-variety, or hyperlexic poor readers, according to the degree of discrepancy between their word recognition and listening comprehension scores. In addition, groups of normal readers were formed, matching the poor readers in either reading age or chronological age. A large test battery was administered to each student, including phonological, naming, working memory, speed of processing, and motor tests. The findings indicate that dyslexia is associated with deficits in (1) phonological recoding, word recognition (both in their native Dutch and in English as a second language), and spelling skills; and (2) naming speed for letters and digits. Dyslexia was not associated with deficits in other areas. The results suggest that developmental dyslexia, at the age of 12, might be (or might have become) a difficulty rather isolated from deficiencies in other cognitive and motor skills.  相似文献   
753.
754.
Background: Due to the limited force feedback provided by laparoscopic instruments, surgeons may have difficulty in applying the appropriate force on the tissue. The aim of this study was to determine the influence of force feedback and visual feedback on the exerted pinch force. Methods: A grasper with a force sensor in the jaws was developed. Subjects with and without laparoscopic experience grasped and pulled pig bowel with a force of 5 N. The applied pinch force was measured during tasks of 1-s and 1-min duration. Visual feedback was provided in half the measurements. Force feedback was adjusted by changing the mechanical efficiency of the forceps from 30% to 90%. Results: The mean pinch force applied was 6.8 N (± 0.5), whereas the force to prevent slippage was 3.0 N ( ± 0.4). Improving the mechanical efficiency had no effect on the pinch force for the 1-s measurements. The amount of excessive pinch force when holding tissue for 1 min was lower at 30% mechanical efficiency compared with 90% (105% vs 131 %, p = 0.04). The tissue slipped more often when the subject had no visual feedback (2% vs 8%, p = 0.02). Conclusion: Force feedback and visual feedbacK playa more limited role than expected in the task of grasping tissue with laparoscopic forceps.  相似文献   
755.
Book reviews     
Varela Gomes, Rosa. Cerâmicas Muçulmanas do Castelo de Silves. Silves: Museu Municipal de Arqueologia, 1988 (XELB, 1). 294pp, numerous figs, and pls.

Rubiera i Mata, María Jesús.Introducció a la literatura hispaho‐àrab (Col. ecció Xarc AI‐Andalus, l).Alicante: Universitat d'Alacant, 1989. 117pp.

Guichard, Pierre. L'Espagne et la Sicile musulmanes aux XIe et XIIe siècles. Lyon: Presses Universitaires de Lyon, 1990. 232pp., figures, maps. FF. 138.‐ ‘ .

Lozano Cámara, Indalecio. Tres tratados árabes sobre el Cannabis Indica. Madrid: Agencia Española de Cooperación Internacional, Instituto de Cooperación con el Mundo Arabe, 1990. 220pp.

Powell, James M., ed. Muslims under Latin Rule, 1100–1300. Princeton: Princeton University Press, 1990. 221pp.

Actas del Simposio Internacional sobre la Ciuidad Islámica. Ponencias y Comunicaciones. Zaragoza: Institución Fernando el Católico de la Diputación Provincial, 1991. 474pp.

Neugebauer, Otto. Abu Shaker's “Chronography”: A treatise of the 13th Century on Chronological, Calendrical and Astronomical Matters, written by a Christian Arab, preserved in Ethiopie (Õsterreichische Akademie der Wissenschaften Philos.‐Histor. Klasse: Sitzungsberichte, 498).Wien: Ö.A.W., 1988. 198pp., 7pl. OS 350.‐.

Arbel, Benjamin, Hamilton, Bernard and Jacoby, David, eds. Latins and Creeks in the Eastern Mediterranean after 1204. London: Frank Cass, 1989. 245pp. £18.  相似文献   

756.
Previous studies that have examined self-efficacy-performance relationships have used novice performers. It is unclear if these findings would generalize to "experienced" performers. Based on Bandura's self-efficacy theory, this study was designed to investigate (a) the effects of false information feedback on self-efficacy beliefs and subsequent weightlifting performance, and (b) whether self-efficacy or past performance is most related to subsequent weightlifting performance. Experienced weightlifters engaged in six performance sessions, each consisting of a one-repetition-maximum bench press. Male subjects (N = 36) were randomly assigned to one of three treatment groups: accurate performance information, false information that they lifted more than their actual lift, or false information that they lifted less than their actual lift. Before each session, subjects indicated the amount of weight they were 100%, 75%, and 50% confident they could lift. Results replicated existing research findings regarding deception and performance; false positive feedback increased future bench press performance. In addition, results indicated that past weightlifting performance accounted for nearly all of the variance in subsequent performance. This finding is discussed in light of the difficulty in extending the predictions of self-efficacy theory to sport settings where athletes have gained experience by undergoing repeated training trials.  相似文献   
757.
A detailed survey of 498 high technology small and medium-sized enterprises in the Netherlands shows process innovation by user firms to be common practice. Fifty-four percent of these firms reported developing entirely novel process equipment or software for their own use and/or modifying these, both at significant private expense. Twenty-five percent of the user innovations in our sample were transferred to commercializing producer firms. Many transfers were made without any direct compensation. Very importantly from the perspective of effective diffusion of user innovations, innovations with higher commercial potential - and more general appeal for users - are much more likely to be transferred to producers. The pattern we document of frequent innovation by individual user firms at substantial cost, followed in many cases by voluntary, no-charge information spillovers to producers, suggests that “open source economics” may be a general pattern in the economy.  相似文献   
758.
The need to economically identify rare subjects within large, poorly mapped search spaces is a frequently encountered problem for social scientists and managers. It is notoriously difficult, for example, to identify “the best new CEO for our company,” or the “best three lead users to participate in our product development project.” Mass screening of entire populations or samples becomes steadily more expensive as the number of acceptable solutions within the search space becomes rarer.The search strategy of “pyramiding” is a potential solution to this problem under many conditions. Pyramiding is a search process based upon the idea that people with a strong interest in a topic or field tend to know people more expert than themselves. In this paper we report upon four experiments empirically exploring the efficiency of pyramiding searches relative to mass screening. We find that pyramiding on average identified the most expert individual in a group on a specific topic with only 28.4% of the group interviewed - a great efficiency gain relative to mass screening. Further, pyramiding identified one of the top 3 experts in a population after interviewing only 15.9% of the group on average. We discuss conditions under which the pyramiding search method is likely to be efficient relative to screening.  相似文献   
759.
The term ‘hypervideo’ has different interpretations in the scientific literature. The aim of this contribution is to define hypervideo as it is and can be (more optimally) used for teaching and learning purposes. Videos can promote learning by recreating real experiences and dynamic processes, although they do not necessarily enable students to interact with contents and to self-regulate their learning. Hypervideos technically overcome these limitations and add further benefits. However, even though some literature on the topic exists, the concept of hypervideo is not well represented in the scientific community and lends itself to different interpretations. Results show that hypervideo is defined as a dynamic artefact, it should allow navigation control and include additional material; it could also integrate individual or collaborative annotation and automated or manual feedback. So far, most studies have been conducted in artificial settings involving tertiary-level students. Finally, its use is beneficial for students’ learning.  相似文献   
760.
The angiogenesis-signalling pathway is a physiological response after mechanical loading to promote matrix remodelling and thereby maintain tissue homeostasis. Studies have shown increased expression of angiogenic molecules in response to loading and in ruptured ligaments. Recently, polymorphisms within the vascular endothelial growth factor A (VEGFA) and kinase insert-domain receptor (KDR) genes were associated with risk of anterior cruciate ligament (ACL) ruptures and Achilles tendinopathy in Caucasian study groups. A case-control genetic association study was conducted on 100 controls and 98 participants with surgically-diagnosed ACL ruptures; of which 51 participants reported non-contact mechanism of injury (NON). All participants were genotyped for five functional polymorphisms: VEGFA (rs699947, rs1570360, rs2010963) and KDR (rs2071559, rs1870377). Haplotypes were inferred. In the male participants, the KDR rs2071559 AG genotype was significantly over-represented (P = 0.048, OR: 1.90, 95% CI: 1.00–3.59) in the controls. Furthermore, the GG genotype was significantly under-represented in the male controls compared to the male ACL group (P = 0.018, OR: 2.77, 95% CI: 1.17–6.55) and the male NON subgroup (P = 0.013, OR: 3.26, 95% CI: 1.24–8.58). Haplotype analysis implicated the KDR gene in all participants and in male participants separately. Collectively, these results implicate the angiogenesis-signalling pathway as a potentially key biological pathway contributing to ACL injury susceptibility.  相似文献   
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