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71.
Abstract

High-level physical performance in rhythmic gymnastics is influenced by numerous skills and anthropometric factors. In order to understand if genetic predisposition could play a role to define the elite rhythmic gymnast phenotype, we analysed the frequency of common polymorphisms linked to genes correlated with body mass (ADRB2 and FTO), explosive strength (ACTN3 and ACE), and joint mobility (COL5A1), in 42 gymnasts involved in National and International events, and in 42 control girls. Our results demonstrated that high-level rhythmic gymnasts constituted a genetically selected population showing higher frequency of: (a) ADRB2 and FTO alleles linked to low body mass index and low fat mass; (b) COL5A1 CT genotype linked to high joint mobility and to the occurrence of genu recurvatum, but also to a higher incidence of injuries. ACTN3 and ACE polymorphisms did not appear to be connected with the phenotype of high-level rhythmic gymnast. Based on these data, it can be assumed that these polymorphisms could positively affect the phenotype and performance of gymnasts.  相似文献   
72.
Higher education systems in competitive environments generally present top universities, that are able to attract top scientists, top students and public and private financing, with notable socio-economic benefits in their region. The same does not hold true for non-competitive systems. In this study we will measure the dispersion of research performance within and between universities in the Italian university system, typically non-competitive. We will also investigate the level of correlation that occurs between performance in research and its dispersion in universities. The findings may represent a first benchmark for similar studies in other nations. Furthermore, they lead to policy indications, questioning the effectiveness of selective funding of universities based on national research assessment exercises. The field of observation is composed of all Italian universities active in the hard sciences. Research performance will be evaluated using a bibliometric approach, through publications indexed in the Web of Science between 2004 and 2008.  相似文献   
73.

Introduction

The study of cardiac response to strenuous and continuous exercise is crucial to understanding the physiology of endurance. N-terminal proB-type natriuretic peptide (NT-proBNP) is a potential marker for monitoring myocardial wall stress, and troponins (TnT and TnI) are widely used in the diagnosis of cardiac ischemia and infarction. Strenuous exercise may generate transitory ischemia, myocardial stress, and diastolic left ventricular dysfunction, inducing the increased production of both these biomarkers. We measured changes in NT-proBNP and TnT in elite cyclists during a 3-week stage race, a model of strenuous exercise.

Materials and methods:

The study population was 9 professional cyclists participating in the 2011 Giro d’Italia. Pre-analytical and analytical phases scrupulously followed official recommendations. Anthropometric data, net energy expenditure and cardiac indexes (rate, diastolic and systolic blood pressure) were recorded. Blood samples were drawn pre-race (day −1) and at days 12 and 22; NT-proBNP and highly sensitive-troponin (Hs-TnT) concentrations were assayed and corrected for plasma volume changes.

Results:

Body-mass index decreased and energy expenditure increased by 52% during the race. NT-proBNP concentrations increased [day −1: 23.52 ng/L (9.67–34.33); day 12: 63.46 ng/L (22.15–93.31); P = 0.039; day 22: 89.26 ng/L (34.66–129.78) vs. day −1; P < 0.001] and correlated with heart rate (r = −0.51; P = 0.006), systolic pressure (r = 0.39; P = 0.046) and energy expenditure (r = 0.70; P < 0.001). TnT concentrations did not vary, but a widened TnT amplitude distribution was observed.

Conclusions:

Increases in NT-proBNP correlated with higher energy expenditure over a 3-week cycling stage race, possibly indicating myocardial stress.  相似文献   
74.
The incidence of extramural collaboration in academic research activities is increasing as a result of various factors. These factors include policy measures aimed at fostering partnership and networking among the various components of the research system, policies which are in turn justified by the idea that knowledge sharing could increase the effectiveness of the system. Over the last two decades, the scientific community has also stepped up activities to assess the actual impact of collaboration intensity on the performance of research systems. This study draws on a number of empirical analyses, with the intention of measuring the effects of extramural collaboration on research performance and, indirectly, verifying the legitimacy of policies that support this type of collaboration. The analysis focuses on the Italian academic research system. The aim of the work is to assess the level of correlation, at institutional level, between scientific productivity and collaboration intensity as a whole, both internationally and with private organizations. This will be carried out using a bibliometric type of approach, which equates collaboration with the co-authorship of scientific publications.
Giovanni AbramoEmail:
  相似文献   
75.
We investigate youths' conceptualization of social robots. Informed by Schudson's theory of the potency of the cultural object, we conducted two studies. The first study centered on essays on social robots written by bachelor's and master's students. The second study centered on prototypes of social robots built by small groups comprised of same students. The essays and prototypes were content analyzed. The results confirm that social robots embody all five dimensions that characterize cultural objects. However, to fully understand this peculiar cultural object, another dimension needs to be introduced: dynamicity.  相似文献   
76.
We report characteristics of in-text citations in over five million full text articles from two large databases – the PubMed Central Open Access subset and Elsevier journals – as functions of time, textual progression, and scientific field. The purpose of this study is to understand the characteristics of in-text citations in a detailed way prior to pursuing other studies focused on answering more substantive research questions. As such, we have analyzed in-text citations in several ways and report many findings here. Perhaps most significantly, we find that there are large field-level differences that are reflected in position within the text, citation interval (or reference age), and citation counts of references. In general, the fields of Biomedical and Health Sciences, Life and Earth Sciences, and Physical Sciences and Engineering have similar reference distributions, although they vary in their specifics. The two remaining fields, Mathematics and Computer Science and Social Science and Humanities, have different reference distributions from the other three fields and between themselves. We also show that in all fields the numbers of sentences, references, and in-text mentions per article have increased over time, and that there are field-level and temporal differences in the numbers of in-text mentions per reference. A final finding is that references mentioned only once tend to be much more highly cited than those mentioned multiple times.  相似文献   
77.
78.
This paper discusses the results for Italy of a CDM model (Crepon et al., 1998) further extended with the objective of evaluating drivers and productivity effects of environmental innovations. The particular nature of environmental innovations, especially as regards the need of government intervention to create market opportunities, is likely to affect the way through which they are pursued (innovation equation within the CDM model) and their effect on productivity (productivity equation).  相似文献   
79.
Physicians’ willingness to share knowledge is a central antecedent of effective knowledge sharing within hospitals. This paper aims at supporting the micro-foundation of knowledge sharing with the identification of the factors that affect willingness to share and their classification according to a behavioural model grounded in the Theory of Planned Behaviour (TPB). The identification of antecedents and their classification is based on the review of the major contributions published on top tier and specialist journals. This study identifies 22 factors that affect physicians’ willingness to share. These factors are classified according to the TPB framework, which identifies three behavioural antecedents: attitude, subjective norm and perceived behaviour control. The organization of the factors allows appreciating the diffusion of knowledge-sharing behaviours as the result of three concurring perspectives: raising attention to the benefits of knowledge sharing, building up social pressures from relevant actors and designing appropriate organizational contingencies.  相似文献   
80.
Bibliometricians have long recurred to citation counts to measure the impact of publications on the advancement of science. However, since the earliest days of the field, some scholars have questioned whether all citations should be worth the same, and have gone on to weight them by a variety of factors. However sophisticated the operationalization of the measures, the methodologies used in weighting citations still present limits in their underlying assumptions. This work takes an alternative approach to resolving the underlying problem: the proposal is to value citations by the impact of the citing articles, regardless of the length of their reference list. As well as conceptualizing a new indicator of impact, the work illustrates its application to the 2004–2012 Italian scientific production indexed in the WoS. The proposed impact indicator is highly correlated to the traditional citation count, however the shifts observed between the two measures are frequent and the number of outliers not negligible. Moreover, the new indicator shows greater “sensitivity” when used to identify the highly-cited papers.  相似文献   
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