The timely diagnosis of acute coronary syndrome (ACS), in particular myocardial infarction (MI), is still one of the most challenging issues in medicine. The introduction into routine laboratory practice of assays for measuring the cardiospecific troponins has dramatically revolutionized the diagnostic approach and the recent development of methods with improved analytical sensibility (i.e., highly sensitivity [HS] assays), has further contributed to improve the negative predictive value of troponin testing but, contextually, has substantially lowered the clinical specificity of these markers. In particular, clinical studies have demonstrated the existence of an exercise-related increase of HS-troponins, with measurable values detectable in up to 94% of athletes undergoing endurance sports. This measurable amount oftroponin in blood would mirror an increased membrane permeability and early troponin release rather than reflecting a clinically threatening myocardial injury. As such, the measurable amount of cardiac troponins as assessed with the novel HS assays requires major clinical focus (i.e., serial measurement of cardiac biomarkers, detailed clinical history-taking, integration with ECG and imaging findings) to prevent misdiagnosis of ACS and/or MI in otherwise healthy persons. 相似文献
Two fear-conditioning experiments with rats assessed whether retrospective revaluation, which has been observed in cue competition (i.e., when compounded cues are followed with an outcome), can also be observed in retroactive cue interference (i.e., when different cues are reinforced in separate phases with the same outcome). Experiment 1 found that after inducing retroactive cue interference (i.e., X-outcome followed by A-outcome), nonreinforced presentations of the interfering cue (A) decreases interference with responding to the target cue (X), just as has been observed in retrospective revaluation experiments in cue competition. Using the opposite manipulation (i.e., adding reinforced presentations of A), Experiment 2 demonstrated that after inducing retroactive cue interference, additional reinforced presentations of the interfering cue (A) increases interference with responding to the target cue (X); alternatively stated, the amount of interference increases with the amount of training with the interfering cue. Thus, both types of retrospective revaluation occur in retroactive cue competition. The results are discussed in terms of the possibility that similar associative mechanisms underlie cue competition and cue interference. 相似文献
Nordic walking (NW), characterized by the use of two walking poles, is becoming increasingly popular (Morgulec-Adamowicz, Marszalek, & Jagustyn, 2011). We studied walking pressure patterns of 20 experienced and 30 beginner Nordic walkers. Plantar pressures from nine foot zones were measured during trials performed at two walking speeds (preferred and 20% faster), and under two walking conditions (NW vs. normal walking). In comparison to normal walking, NW experience led to a significant (p < .05) pressure reduction of about 50% on the central metatarsals. No significant increases were detected in other foot regions. The differences between experienced and beginners during normal walking including a 40% pressure reduction on the metatarsal area, suggests that regular NW practice might also have a beneficial effect on plantar pressure when walking without poles. 相似文献
The warm-up programme “FIFA 11+” has been shown to reduce football injuries in different populations, but so far veteran players have not been investigated. Due to differences in age, skill level and gender, a simple transfer of these results to veteran football is not recommended. The purpose of this study was to investigate the preventive effects of the “FIFA 11+” in veteran football players.
Twenty veteran football teams were recruited for a prospective 9-month (1 season) cluster-randomised trial. The intervention group (INT, n = 146; 45 ± 8 years) performed the “FIFA 11+” at the beginning of each training session, while the control group (CON, n = 119; 43 ± 6 years) followed its regular training routine. Player exposure hours and injuries were recorded according to an international consensus statement.
No significant difference was found between INT and CON in overall injury incidence (incidence rate ratio [IRR]: 0.91 [0.64–1.48]; P = 0.89). Only severe injuries reached statistical significance with higher incidence in CON (IRR: 0.46 [0.21–0.97], P = 0.04).
Regular conduction (i.e. once a week) of the “FIFA 11+” did not prevent injuries in veteran footballers under real training and competition circumstances. The lack of preventive effects is likely due to the too low overall frequency of training sessions. 相似文献
Along the Umbria-Marche stretch of the Flaminia Consular Road (220 B.C.) several archaeological finds of the most important monumental works, are well preserved. The stones, employed to build many bridges, substructions and sewerages, are represented by carbonatic breccias whose geological environment of formation and source areas had never been established. On the basis of mineralogical, petrographic and micropalaeontological analyses, two groups of these lithotypes employed in Roman age were distinguished: “monogenic carbonatic breccias” only constituted by clasts of the Maiolica Unit (Late Jurassic – Early Cretaceous) and “polygenic carbonatic breccias” made of fragments (in different proportions) of Calcare Massiccio (Early Jurassic), Corniola (Early Jurassic), Maiolica (Late Jurassic – Early Cretaceous) and Scaglia Rossa (Late Cretaceous – Early Paleogene) Units. The possible source areas of the breccias are compatible with stratified slope-waste to scarp-base deposits of periglacial origin belonging to the Upper Pleistocene. In particular, among the seven investigated areas, we pointed out the most probable provenances (Monte Faeto-Colle, Costacciaro, Scirca, Foci, Secchiano) along the flanks of the Apennine Mesozoic chain of the Umbria and Marche regions. Although the Romans could have exploited the whole thickness of some outcrops (now disappeared) of these carbonatic lithotypes at the deepest part of the valleys, we have constrained a local provenance of the breccias so commonly used in the monumental works of the Flaminia. 相似文献
ResumenEn los últimos años se han desarrollado dos concepciones distintas del alumno adolescente en relación con la enseñanza de la ciencia. Por un lado, se ha analizado a los alumnos en términos de su capacidad para el pensamiento formal y, por otro, se han descrito innumerables concepciones espontáneas desviadas que los alumnos adolescentes poseen con respecto a los fenómenos científicos. El presente artículo revisa y compara los fundamentos epistemológicos y psicológicos de ambos enfoques, además de revisar las implicaciones didácticas que se derivan de cada una de esas posiciones para la enseñanza de la ciencia. 相似文献