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71.
Abstract

The aim of this study was to quantify the changes in locomotive rates across the duration of senior elite rugby league matches. A semi-automated image recognition system (ProZone 3, ProZone®, Leeds, England) was used to track the movements of 59 players from six teams during three competitive matches. The players were classified into one of four positional groups: props (n = 9), back row (n = 9), pivots (n = 14) or outside backs (n = 27). Players' movements were classified as low, high or very high intensity running and reported as locomotive rates (distance covered per minute played) for successive quarters of each match. Analysis of variance revealed that only the outside backs showed a significantly lower overall locomotive rate during the final quarter compared to the first (P < 0.05). However, locomotive rates for high and very high intensity running during the final quarter were significantly lower (P < 0.05) than the first quarter among outside backs, pivots and props despite no change in the rate of involvements in contact. On the basis of these findings, it is suggested that high and very high intensity running locomotive rates may be more affective methods of detecting fatigue during competitive matches than overall locomotive rate.  相似文献   
72.
The aim of this study was to assess the sensitivity of the lactate minimum speed test to changes in endurance fitness resulting from a 6 week training intervention. Sixteen participants (mean +/- s :age 23 +/- 4 years;body mass 69.7 +/- 9.1 kg) completed 6 weeks of endurance training. Another eight participants (age 23 +/- 4 years; body mass 72.7 +/-12.5 kg) acted as non-training controls. Before and after the training intervention, all participants completed: (1) a standard multi-stage treadmill test for the assessment of VO 2max , running speed at the lactate threshold and running speed at a reference blood lactate concentration of 3 mmol.l -1 ; and (2) the lactate minimum speed test, which involved two supramaximal exercise bouts and an 8 min walking recovery period to increase blood lactate concentration before the completion of an incremental treadmill test. Additionally, a subgroup of eight participants from the training intervention completed a series of constant-speed runs for determination of running speed at the maximal lactate steady state. The test protocols were identical before and after the 6 week intervention. The control group showed no significant changes in VO 2max , running speed at the lactate threshold, running speed at a blood lactate concentration of 3 mmol.l -1 or the lactate minimum speed.In the training group, there was a significant increase in VO 2max (from 47.9 +/- 8.4 to 52.2 +/- 2.7 ml.kg -1 .min -1 ), running speed at the maximal lactate steady state (from 13.3 +/- 1.7 to 13.9 +/- 1.6 km.h -1 ), running speed at the lactate threshold (from 11.2 +/- 1.8 to 11.9 +/- 1.8 km.h -1 ) and running speed at a blood lactate concentration of 3 mmol.l -1 (from 12.5 +/- 2.2 to 13.2 +/- 2.1 km.h -1 ) (all P ? 0.05). Despite these clear improvements in aerobic fitness, there was no significant difference in lactate minimum speed after the training intervention (from 11.0 +/- 0.7 to 10.9 +/- 1.7 km.h -1 ). The results demonstrate that the lactate minimum speed,when assessed using the same exercise protocol before and after 6 weeks of aerobic exercise training, is not sensitive to changes in endurance capacity.  相似文献   
73.
Understanding what influences an individual to transition from awareness that a sport team exists to attraction to that team is of critical importance in the management and development of consumer bases. Determining the factors that prevent individuals at a stage of awareness from becoming attracted is of equal importance. In this paper we use a social identity approach to explore reasons for non-attendance. Qualitative data were gathered from a mixed-method online survey administered to registered participants in a large football (soccer) association in New South Wales. The questionnaire included an open-ended question allowing individuals who had not attended a match during the previous 12 months to elaborate on the reasons that they did not attend. The seventy-five individuals who responded to this open-ended question comprise the sample for this research. Data highlighted that cognitive apathy and disidentification were both salient cognitive responses associated with individuals who did not attend. Furthermore, club values and characteristics were shown to influence team-based perceptions. The findings present implications for sport teams to overcome cognitive apathy and disidentification through organisation-initiated efforts to disseminate information and promote the team, as well as efforts to align team characteristics and values with consumer perceptions.  相似文献   
74.
75.
Human generated environmental problems are significant issues of global concern. Despite this, varying attitudes towards environments continue to exist across the globe, impacting on environmental decision-making and action at local, national and international levels. This paper probes some of the similarities and differences in environmental attitudes amongst pre-service teachers in Australia, Republic of Maldives and Indonesia. Data were collected using an established environmental attitude questionnaire and individual interviews. The three communities exhibited a similar range of environmental attitudes using the established questionnaire but significant differences emerged when the interview data were analysed phenomenographically. These differences reflect diversity within and across cultural groups that cannot be satisfactorily explained by the theory underpinning the established questionnaire. Consequently, a revised conceptual framework is proposed.  相似文献   
76.
Working memory training improves children's cognitive performance on untrained tasks; however, little is known about the underlying neural mechanisms. This was investigated in 32 typically developing children aged 10–14 years (19 girls and 13 boys) using a randomized controlled design and multi-modal magnetic resonance imaging (Devon, UK; 2015–2016). Training improved working memory performance and increased intrinsic functional connectivity between the bilateral intraparietal sulci. Furthermore, improvements in working memory were associated with greater recruitment of the left middle frontal gyrus on a complex span task. Repeated engagement of fronto-parietal regions during training may increase their activity and functional connectivity over time, affording greater working memory performance. The plausibility of generalizable cognitive benefits from a neurobiological perspective and implications for neurodevelopmental theory are discussed.  相似文献   
77.
Concern has been expressed about the vulnerability of the ‘academic profession’ as a consequence of threats from productivism, managerialism and the like (Beck and Young, Br J Sociol Educ 26(2):183–197, 2005). I question the apparent self-understanding of academe as a profession. Referring to thinking from higher education (Barnett, High Educ 40:409–422, 2000a; Educ Phil Theor 32(3):319–326, 2000b; Realizing the University in an age of supercomplexity, 2000c; Stud High Educ 25(3):255–265, 2000d; Lond Rev Educ 2(1):61–73, 2004a; Piper, Are professors professional? The organisation of University examinations, 1994; Taylor 1999), and from the sociology of the professions (in particular Evetts, Int J Sociol Soc Policy 23(4/5):22–35, 2003a; Int Sociol 18(2):395–415 2003b; Curr Sociol 54(1):133–143 2006a; Curr Sociol 54(4):515–531, 2006b), I propose that significant shifts in self-understanding and practice are needed for academe to claim a social role as a ‘profession’.  相似文献   
78.
OBJECTIVE: Children's Advocacy Centers (CACs) aim to improve child forensic interviewing following allegations of child abuse by coordinating multiple investigations, providing child-friendly interviewing locations, and limiting redundant interviewing. This analysis presents one of the first rigorous evaluations of CACs' implementation of these methods. METHODS: This analysis is part of a quasi-experimental study, the Multi-Site Evaluation of Children's Advocacy Centers, which evaluated four CACs relative to within-state non-CAC comparison communities. Case abstractors collected data on investigation methods in 1,069 child sexual abuse cases with forensic interviews by reviewing case records from multiple agencies. RESULTS: CAC cases were more likely than comparison cases to feature police involvement in CPS cases (41% vs. 15%), multidisciplinary team (MDT) interviews (28% vs. 6%), case reviews (56% vs. 7%), joint police/child protective services (CPS) investigations (81% vs. 52%) and video/audiotaping of interviews (52% vs. 17%, all these comparisons p<.001). CACs varied in which coordination methods they used, and some comparison communities also used certain coordination methods more than the CAC with which they were paired. Eighty-five percent of CAC interviews took place in child-friendly CAC facilities, while notable proportions of comparison interviews took place at CPS offices (22%), police facilities (18%), home (16%), or school (19%). Ninety-five percent of children had no more than two forensic interviews, and CAC and comparison differences on number of interviews were mostly non-significant. CONCLUSIONS: Relative to the comparison communities, these CACs appear to have increased coordination on investigations and child forensic interviewing. The CAC setting was the location for the vast majority of CAC child interviews, while comparison communities often used settings that many consider undesirable. CACs showed no advantage on reducing the number of forensic interviews, which was consistently small across the sample.  相似文献   
79.
OBJECTIVE: Most research on child abuse in Tanzania and Kenya is unpublished in the international literature. The purpose of this paper is to examine the various commentaries and reports extant, toward an overview of the nature and frequency of child sexual abuse in Tanzania and Kenya. METHODS: Contacts were made with academics, government departments, NGOs, and UN agencies. This was followed by a field trip in the summer of 2001 where all available reports were examined and a wide range of interviews conducted. RESULTS: Little empirical data exist on child sexual abuse in Tanzania. It is widely perceived that it may be increasing as a result of AIDS sufferers' attempts to "cleanse" themselves. The breakdown of traditional childcare systems, foreign influences, poverty, and the lowly position of girls in society are also implicated. More research has been conducted in Kenya. It is clear that first coitus occurs at a young age for many Kenyan children and adolescents. Also, a degree of force, trickery, or material exchange is not uncommon in adolescent sexual relations. CONCLUSIONS: Child sexual abuse is under-researched in Tanzania and Kenya. Studies by UN agencies such as United Nations Children's Fund (UNICEF) and the International Labour Organisation (ILO) have focused on the commercial sexual exploitation of children, to the neglect of more pervasive abuse in children's own communities by family, relatives, and neighbors. Nationwide surveys of the general population are required for an empirical understanding of this topic. Given the high incidence of AIDS/HIV in both countries, it is important to know if the epidemic is increasing the risk of rape or incest for children.  相似文献   
80.
Automatic detection of source code plagiarism is an important research field for both the commercial software industry and within the research community. Existing methods of plagiarism detection primarily involve exhaustive pairwise document comparison, which does not scale well for large software collections. To achieve scalability, we approach the problem from an information retrieval (IR) perspective. We retrieve a ranked list of candidate documents in response to a pseudo-query representation constructed from each source code document in the collection. The challenge in source code document retrieval is that the standard bag-of-words (BoW) representation model for such documents is likely to result in many false positives being retrieved, because of the use of identical programming language specific constructs and keywords. To address this problem, we make use of an abstract syntax tree (AST) representation of the source code documents. While the IR approach is efficient, it is essentially unsupervised in nature. To further improve its effectiveness, we apply a supervised classifier (pre-trained with features extracted from sample plagiarized source code pairs) on the top ranked retrieved documents. We report experiments on the SOCO-2014 dataset comprising 12K Java source files with almost 1M lines of code. Our experiments confirm that the AST based approach produces significantly better retrieval effectiveness than a standard BoW representation, i.e., the AST based approach is able to identify a higher number of plagiarized source code documents at top ranks in response to a query source code document. The supervised classifier, trained on features extracted from sample plagiarized source code pairs, is shown to effectively filter and thus further improve the ranked list of retrieved candidate plagiarized documents.  相似文献   
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