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Coxsackievirus B (CVB) is a significant pathogen that causes pediatric central nervous system disease with acute syndromes commonly. The onset of its infection was abrupt, and after recovery there usually will be severe mental sequelae. The disease model for research was not established by the way of natural infection, although there are various investigations about the CVB-induced central nervous system (CNS) diseases. Thus, we have established an acute neonatal CNS disease mice model by CVB orally infecting. This model imitated the natural infection route and focuses the onset of CNS disease, inducing severe infection and lesion in the hippocampus and cortex regions, and the stability of the model was demonstrated. A pathology score system was developed for quantitative pathology analysis, which standardizes the CNS pathology analysis by statistics analysis. By this model, the track of CVB penetrating the blood brain barrier in vivo has been captured. One of the experimental strains CVB3/Macocy, as a new variant, was isolated, and its genomic RNA was cloned. According to its nucleotide sequence, we have characterized its genomic structure and defined its genotype. Based on the sequence, some mutations which do not change the CVB-induced CNS damage have been found. The model is an effective tool for studies on CVB-induced CNS diseases.  相似文献   
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The identification of a sub-endocardial infarction is of major interest in cardiology. This study evaluates the sensitivity of selected measures to the thickness of such an infarction. Synthetic ultrasonic data (long-axis view) of left ventricular models with inclusions were generated using Field II and meshes obtained from finite-element simulations, which also provided the reference for the estimates obtained from ultrasonic data. The displacements, the first and second component of the principal strain (ε1 and ε2), and several measures derived from these quantities were estimated. All estimates, except for the poorly estimated ε2, exhibited sensitivity to the presence and transmurality of the inclusion. The most sensitive was the gradient of the averaged transmural profiles of ε1, and ε1 averaged over the area corresponding to the transmural inclusion. The inflection point of the ε1 profile shifted toward the outer wall with increasing thickness of the non-transmural inclusion.  相似文献   
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This paper is focused on the mechanical properties and the energy absorption characteristics of the extruded Mg-Al-Ca-Mn alloy in different compression directions under high strain rate compression. Compressive characterization of the alloy was conducted from the high strain rate (HSR) test by using a Split Hopkinson Pressure Bar (SHPB). Results show that the investigated alloy exhibits a strong strain rate sensitivity. With the rise of strain rate, the compressive strength is increased significantly, and the deformation ability also improves. When compressed along the extrusion direction, as the strain rate increases, the total absorbed energy E, the crush force efficiency (CFE), and the specific energy absorption SEA of Mg-Al-Ca-Mn alloy are all greatly improved as compared with those obtained along other compression directions.  相似文献   
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The number of young adults with hypertension (HT) is increasing. We investigated the changes of left ventricular (LV) function and their relationship to the ambulatory blood pressure monitoring (ABPM) parameters in young adults with never-treated HT and no LV hypertrophy.

Consecutive young patients (29.5?±?5.9 years) with first diagnosed primary HT and sex- and age-matched normotensive controls were enrolled. We excluded patients who had LV hypertrophy. ABPM was performed in all HT patients. LV strain values were obtained by two-dimensional speckle tracking imaging.

There was no difference in LV ejection fraction and mass index between HT patients (n?=?40) and controls (n?=?40). LV global longitudinal strain (GLS) was lower (p?=?0.001) and twist was higher (p?=?0.002) in HT patients than in controls. LV GLS was significantly correlated to averaged and daytime diastolic BP and its variability and most related to daytime diastolic BP (β?=?0.33, p?=?0.03). Patients with high daytime diastolic BP and its variability showed lower GLS (both p?=?0.02) and higher twist (both p?=?0.04) than patients with low daytime diastolic BP.

Early changes of LV function with decreased GLS and increased twist were shown in young HT patients even with no LV hypertrophy and daytime diastolic BP and its variability were related to the impairment of LV function.  相似文献   
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