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111.

Introduction

The aim of this study was to identify clinical variables which may be independently associated with positivity of a cardiac troponin I (cTnI) assay in a large population of patients admitted to the emergency department (ED).

Materials and methods

3166 subjects, with at least two troponin I tests ordered within 6 hours in the ED, were studied. Patient data were statistically analyzed to identify clinical associations with increased values of Troponin I.

Results

Although patients with diagnosis of acute coronary syndrome displayed troponin I values significantly higher than those of other groups, positivity to troponin I (> 40 ng/L) was also observed in patients with other clinical conditions. In multivariate analysis, age, elevated heart rate and electrocardiographyc changes were independently associated with troponin I positivity at admission. In the whole study population troponin I positivity exhibited high sensitivity and negative predictive value, counterbalanced by low specificity and limited positive predictive value.

Conclusions

Troponin I positivity should be combined with history and clinical evaluation and cautiously interpreted in the ED, especially in patients exhibiting factors associated with higher troponin I levels such as older age, elevated heart rate or ECG changes.Key words: troponin I, acute coronary syndrome, emergency service, hospital, chest pain  相似文献   
112.
In this paper, we analyze the compelling issue of monetary valuation of a scientific publication. While many academic scholars tend to overlook the topic, as being either too difficult or even meaningless, policymakers begin to use very rough tools for evaluating publications, which have many limitations, as we will discuss in this work. The main objective of this work is to address this open problem by stimulating further discussion on the topic and future research developments. We provide an overview of different methods to value scientific publications. We discuss their main hypotheses, pros and cons by means of an illustration based on Sapienza University of Rome. Although we begin to address the issue of monetary valuation of scientific publications, presenting a range of available methods and listing the limits and benefits of each, further methodological and empirical research is still needed to comply with policy and stakeholders' needs which we expect will increase in the near future.  相似文献   
113.
At the down of the third millennium, it is rather misleading to consider the “whole population” as a conceptual entity, whereby the population is actually composed by single individuals, who differ broadly in terms of age, sex, ethnic origin, occupation, health, wellbeing, lifestyle and risk factors. While reaffirming strongly that laboratory medicine shall aim to provide data that could be translated into actionable information on “BOTH” an individual and universal level, we confute and refuse the naive and too simplistic approach that the common beneficence shall always be prioritized over the individual good, since the common good is just the sum of many individual beneficences.  相似文献   
114.
Despite official government srt (in various jurisdictions around the world) for providing students with opportunities to construct their own knowledge within the context of formal schooling, school science systems continue to place greatest priority on teaching and learning of products of science (e.g., laws and theories), while compromising students’ opportunities to develop realistic conceptions about science and expertise for doing science. Based on qualitative data analyzed using constant comparative methods (based on constructivist grounded theory), we found this also to be the case – paradoxically – in a school belonging to the Canadian Coalition for Self-directed Learning (CCSDL). Schools in this coalition espouse, among various goals, enabling students to construct their own knowledge, in ways and directions suiting their individual needs, interests, perspectives, and abilities, in addition to gaining access to knowledge developed by society. The science department within the coalition school in this study experienced considerable difficulty realizing this goal, despite school-level administrative support for a concerted effort to reinvent itself along these lines. Factors that appeared to influence the science department’s efforts included those in each of Schwab’s (1969) educational "commonplaces;” that is, the curriculum, teachers, students, and the milieu surrounding teaching and learning. Further analysis suggests that results can be explained through reference to a Kuhnian (1962/1996) paradigm conflict – in which the school’s administrative and curricular committee and other members of the CCSDL were unsuccessful in convincing members of the science department (who, in turn, appeared to be supported by the provincial government, parents, and students) to make provisions for more student-directed, openended science inquiry. Assuming that student-led scientific inquiry continues to be an important curricular goal, efforts must continue to be made, therefore, to convince members of the mainstream paradigm that it is a worthy goal.  相似文献   
115.
Critical reflexivity has been acknowledged as fundamental in higher education. For facing complex situations in turbulent environments, students nowadays need not only to be taught technical knowledge, but also to be helped develop “relevant” learning for their future professional practice. In recent years, scholars have concentrated on what makes the internship experience a successful opportunity for the parties involved, and have also discussed the crucial role of a mentor/tutor in sustaining relevant and effective learning. However, the specific conditions that make tutorship successful in promoting critical reflexivity in such a boundary crossing experience need to be further explored. Aim of this paper is therefore to analyze what tutorship conditions sustain the development of critical reflexivity in internship. For this purpose, we will present the case study of an internship program run by one of the largest universities in northern Italy.  相似文献   
116.
The present study aimed to investigate the effects of a standardized fatiguing protocol on central and peripheral fatigue in knee-flexors and knee-extensors. Thirteen healthy men (age: 23?±?3 years; height: 1.78?±?0.09 m; body-mass: 73.6?±?9.2?kg) volunteered for the present study. Maximal voluntary contraction (MVC), Electromyography (EMG) activity, voluntary activation level (VAL) as an index of central fatigue and twitch potentiation as an index of peripheral fatigue were measured before and after the fatiguing protocol. The fatiguing protocol consisted of a 0.6 duty-cycle to exhaustion (6?s isometric contraction, 4?s recovery) at 70% MVC. After the fatiguing protocol, MVC decreased in both (Effect-size (ES)?=?1.14) and knee-extensors (ES?=?1.14), and EMG activity increased in both knee-flexors (ES?=?2.33) and knee-extensors (ES?=?1.54). Decreases in VAL occurred in knee-flexors (ES?=?0.92) but not in knee-extensors (ES?=?0.04). Decreases in potentiation occurred in both knee-flexors (ES?=?0.84) and knee-extensors (ES?=?0.58). The greater central occurrence of fatigue in knee-flexors than in knee-extensors may depend on the different muscle morphology and coupled with a greater tolerance to fatigue in knee-extensors. The present data add further insight to the complicated knee-flexors-to-knee-extensors strength relationship and the mechanisms behind the different occurrence of fatigue.  相似文献   
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