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31.

Background

Early diagnosis is crucial for management of patients with suspected acute myocardial infarction (AMI). Among innovative and promising biomarkers, the recent interest raised on glycogen phosphorylase isoenzyme BB (GPBB) has prompted us to perform a meta-analysis of published studies.

Materials and methods:

A systematic electronic search was carried out on PubMed, Web of Science and Google Scholar, with no date restriction, to retrieve all articles that have investigated the early diagnostic performance of GPBB in patients with suspected AMI, and directly reported or allowed calculation of sensitivity and specificity. A meta-analysis of the reported sensitivity and specificity of each study and pooled area under the curve (AUC) was then performed by random effect approach. Heterogeneity was assessed by I-square statistics.

Results:

Eight studies were finally selected for analysis (941 subjects; 506 cases and 435 controls), with a high heterogeneity (I-squared, 86.3%). The resulting pooled estimates and 95% confidence interval were 0.854 (0.801–0.891) for sensitivity, 0.767 (0.713–0.815) for specificity, 0.826 (0.774–0.870) for negative predictive value, 0.802 (0.754–0.844) for positive predictive value, and 0.754 (0.602–0.907) for AUC. In those studies that have simultaneously assessed GPBB and a troponin immunoassay, the combination of these biomarkers did not significantly improve the performance of troponin alone.

Conclusion:

GPBB does not meet the current requirements for an efficient diagnosis of AMI when used as a stand-alone test, whereas its combination with troponin merits further investigation in larger trials.  相似文献   
32.
The paper describes the numerical techniques implemented in the finite-element code NOSA for structural analysis of masonry constructions. The code is then applied to the analysis of “Buti’s bell tower”, a medieval structure located on the Pisa mountains, under two different conditions: firstly, with the structure subjected to its own weight alone, and then while subjected to both its own weight and a horizontal load, which models an earthquake. The displacement and stress fields, as well as the distribution of cracking have been calculated with NOSA, and the numerical results analysed and compared to the actual distribution of fractures in the tower.  相似文献   
33.
Reading and written spelling skills for words and non-words of varying length and orthographic complexity were investigated in normal Italian first and second graders. The regularity and transparency of the mapping between letters and phonemes make Italian orthography an unlikely candidate for discrepancies between reading and spelling to emerge. This notwithstanding, the results showed that reading accuracy is significantly better than spelling. The difference is particularly striking in first graders, but it is still evident in 2nd graders, though most strongly on non-words. The data show that reading and written spelling are non parallel processes and that the developmental asynchrony reflects a partial structural independence of the two systems.  相似文献   
34.
35.
We studied the conceptions of students coming from secondary education and university regarding the number line as a representation of real numbers. In the context of a wider questionnaire, 307 students were presented with a task consisting of two verbal items and one graphic item related to the number line. The students were all at different levels in their study of mathematics (in the third, fourth or fifth year of secondary education, or at the beginning or advanced stage of a university degree in mathematics, biology or physical education). A gradient in the depth of the students’ conceptions, associated with the level of their studies in mathematics, was found. This gradient extends from the estrangement of facing the problem or a conception of a drawn or physical matter line, which was associated with students with a lower level of mathematical studies, passing through a vision centred around potential numeric density or a line containing points (discrete), up to an instrumental conception of the line as supportive of magnitudes in advanced students of biology and focusing on continuity sustained by advanced students of mathematics.  相似文献   
36.
Research in Science Education - This paper reports the findings from a cross-sector research project designed to question how the development of university-school partnerships can influence...  相似文献   
37.
Classifying people into categories not only helps humans simplify a complex social world but also contributes to stereotyping and discrimination. This research examines how social categorization develops by testing how language imbues with meaning otherwise arbitrary differences between people. Experimental studies (= 129) with 2‐year‐olds showed that generic language—language that refers to abstract kinds—guides the development of social categorization. Toddlers learned a new category after hearing generic language about individuals who shared an arbitrary perceptual feature but not after hearing matched specific language, simple labels, or plural (but nongeneric) language about the same set of individuals. These findings show how subtle linguistic cues shape the development of social categorization.  相似文献   
38.
The impact of the geographical origin of patents on the probability of an opposition being filed and a patent being revoked has been examined in this paper, after accounting for patent value indicators and industry specificities. The study is based on a dataset of approximately 450,000 EPO granted patents and 24,000 patent opposition cases in the years 2000–2008. We find that patents with a first priority in the US are less likely to be challenged, although they are relatively more likely to be revoked than patents with a priority in a member country of the European Patent Convention. Patents from Japan have less probability of being opposed and are less likely to be revoked than the other countries. A disaggregation of the European countries has revealed that patents with a German priority have a higher or similar likelihood of being opposed than patents from the other countries, with the exceptions of The Netherlands and Denmark.  相似文献   
39.
Abstract

In this study, we examined the mechanics and energetics of locomotion with a paddle-wheel boat and a water bike. Power output ([Wdot] tot) was measured directly on the water bike by means of an instrumented chain-ring. The simultaneous assessment of oxygen uptake ([Vdot]O2) allowed the computation of the “overall” efficiency of locomotion (η o = [Wdot] tot / [Vdot]O2). Mean η o was 0.27 (s = 0.02), which was unaffected by the speed, and was assumed to be the same for the two boats as both are semi-recumbent bicycles. For the paddle-wheel boat, [Wdot] tot was then obtained from η o and measures of [Vdot]O2. The power to overcome (passive) drag was calculated as [Wdot] d = D · v (where D is the force measured by means of a load cell when towing the boats at given speeds). Propelling efficiency was calculated as η p = [Wdot] d / [Wdot] tot, which was lower with the paddle-wheel boat (mean 0.35, s = 0.01) than with the water bike (mean 0.57, s = 0.01). The observed differences in η p and [Wdot] d explain why at the highest speed tested (~3 m · s?1), the energy required to cover a unit distance with the water bike is similar to that required to move the paddle-wheel boat at 1.3 m · s?1.  相似文献   
40.
Abstract

Runners have increased numbers of neutrophils in the airways at rest and after exercise compared with sedentary individuals. The aim of this study was to determine whether Mediterranean seasonal changes in temperature, humidity or airborne pollutants affect the airway cells of runners training outdoors in an urban environment. In nine male amateur runners, cell composition, apoptosis, and inflammatory mediators were measured in induced sputum collected at rest (baseline) and the morning after races held in the fall (21 km), winter (12 km), and summer (10 km). Concentrations of air pollutants were below the alert threshold at all times. Neutrophil differential counts tended to increase after all races (P = 0.055). Apoptosis of neutrophils increased with ozone (P < 0.005) and particulate matter <10 μm (PM10) (P < 0.05) exposure. Bronchial epithelial cell counts were low at all times and weakly correlated with ozone and PM10 concentrations. Apoptotic bronchial epithelial cells increased after all races (P < 0.05). Inflammatory mediators in induced sputum were low at baseline and after the races, and correlated with neutrophil differential counts only at rest. In conclusion, apoptosis of airway cells in runners appears to be affected by both exercise and environmental conditions. Apoptosis of neutrophils increased with exposure to environmental pollutants while apoptosis of bronchial epithelial cells increased after intense exercise. Since no relationship was observed between neutrophil counts and inflammatory mediators 20 h after races, airways inflammation at this time point appears blunted in healthy runners and little affected by exposure to mild seasonal changes and airborne pollutants.  相似文献   
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