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Transient left ventricular apical ballooning syndrome was first described in Japan as "Takotsubo cardiomyopathy." This syndrome has been identified in many other countries. Many variations of this syndrome have been recently described in the literature. One of the rarest is the reverse type of this syndrome, with hyperdynamic apex and complete akinesia of the base (as opposed to the classic apical ballooning). In this article, we report an interesting case of a young woman who presented with this rare type of reverse apical ballooning syndrome occurring after amphetamine use. This report is followed by review of the literature.  相似文献   
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Metabolic Brain Disease - Bile secretion is a physiological function that is disrupted following Bile Duct Ligation (BDL) and induces cholestasis. Cholestasis is a bile flow reduction that induces...  相似文献   
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BACKGROUND: Polyethylene Glycol (PEG) is a solvent and used in a wide range of biomedical applications. Many fatty-acid-based molecules cannot be administered without a solvent in vivo. PEG can be used to dissolve compounds to make them water soluble. However, the effect of PEG on the cardiovascular system has not been studied. In this study, we evaluated the effect of PEG on the cardiovascular system in rat models. METHODS: Twenty male Sprague-Dawley rats weighing 250-300 g were used in this study. The control group (10 rats) were injected intraperitoneally with 0.5 ml of 5% D/W in normal saline and the second group (10 rats) with PEG 400, 2 ml/kg ip, twice a day for 1 week. After 4 weeks, the rats underwent general anesthesia and a 1.4 French ultra miniature pressure volume catheter (Millar catheter) was placed in the left ventricle via the right carotid artery to measure comprehensive hemodynamic data. The data were analyzed with PVAN pressure-volume analysis software. RESULTS: All the systolic and diastolic parameters were similar in both groups except for the effective arterial elastance (Ea), which was decreased in the PEG group. There were no significant differences in maximum (dp/dt(max)) and minimum (dp/dt(min)) development of pressure stroke work, cardiac output, ejection fraction, end systolic volume (Ves), and end diastolic volume. CONCLUSIONS: We have demonstrated that PEG, as a solvent, decreases Ea in rats in comparison to a placebo. Therefore, PEG as a solvent should be used cautiously in the cardiovascular research.  相似文献   
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BackgroundThere is a paucity of interventional research that systematically assesses the role of exercise intensity and cardiorespiratory fitness, and their relationship with executive function in older adults. To address this limitation, we have examined the effect of a systematically manipulated exercise intervention on executive function.MethodsNinety-nine cognitively normal participants (age = 69.10 ± 5.2 years; n = 54 female) were randomized into either a high-intensity cycle-based exercise, moderate-intensity cycle-based exercise, or no-intervention control group. All participants underwent neuropsychological testing and fitness assessment at baseline (preintervention), 6-month follow-up (postintervention), and 12-month postintervention. Executive function was measured comprehensively, including measures of each subdomain: Shifting, Updating/ Working Memory, Inhibition, Verbal Generativity, and Nonverbal Reasoning. Cardiorespiratory fitness was measured by analysis of peak aerobic capacity; VO2peak.ResultsFirst, the exercise intervention was found to increase cardiorespiratory fitness (VO2peak) in the intervention groups, in comparison to the control group (F =10.40, p≤0.01). However, the authors failed to find mean differences in executive function scores between the high-intensity, moderate intensity, or inactive control group. On the basis of change scores, cardiorespiratory fitness was found to associate positively with the executive function (EF) subdomains of Updating/Working Memory (β = 0.37, p = 0.01, r = 0.34) and Verbal Generativity (β = 0.30, p = 0.03, r = 0.28) for intervention, but not control participants.ConclusionAt the aggregate level, the authors failed to find evidence that 6-months of high-intensity aerobic exercise improves EF in older adults. However, it remains possible that individual differences in experimentally induced changes in cardiorespiratory fitness may be associated with changes in Updating/ Working Memory and Verbal Generativity.  相似文献   
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Purpose

Functional magnetic resonance imaging (fMRI) in resting state can be used to evaluate the functional organization of the human brain in the absence of any task or stimulus. The functional connectivity (FC) has non-stationary nature and consented to be varying over time. By considering the dynamic characteristics of the FC and using graph theoretical analysis and a machine learning approach, we aim to identify the laterality in cases of temporal lobe epilepsy (TLE).

Methods

Six global graph measures are extracted from static and dynamic functional connectivity matrices using fMRI data of 35 unilateral TLE subjects. Alterations in the time trend of the graph measures are quantified. The random forest (RF) method is used for the determination of feature importance and selection of dynamic graph features including mean, variance, skewness, kurtosis, and Shannon entropy. The selected features are used in the support vector machine (SVM) classifier to identify the left and right epileptogenic sides in patients with TLE.

Results

Our results for the performance of SVM demonstrate that the utility of dynamic features improves the classification outcome in terms of accuracy (88.5% for dynamic features compared with 82% for static features). Selecting the best dynamic features also elevates the accuracy to 91.5%.

Conclusion

Accounting for the non-stationary characteristics of functional connectivity, dynamic connectivity analysis of graph measures along with machine learning approach can identify the temporal trend of some specific network features. These network features may be used as potential imaging markers in determining the epileptogenic hemisphere in patients with TLE.

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Ocular ultrasonography is a valid and non-invasive diagnostic method used to evaluate ocular and retrobulbar structures, especially when opacity of the anterior segments precludes ophthalmic examination of deeper structures of the eye or when exophthalmos is present. This study describes the B-mode ultrasonographic findings of the globe in 10 rabbits with experimental glaucoma. Ultrasonography of the eyes, using Titan TM machine and 7 MHz linear array transducer, was performed transpalpebrally. Ocular ultrasonographic findings revealed two cases of increased corneal thickness, seven cases of change in the anterior chamber depth, one case of increased echogenicity in the anterior chamber, three cases of retinal detachment, one case of increased iris and ciliary body thickness and six cases of change in axial globe length. Increased echogenicity of the capsule, cortex and nucleus was found in two cases. Six cases showed change in lens diameter. Increased echogenicity and altered lens diameter are typical of cataract. Two cases of point-like lesions, mass and/or linear echodensities in mild extent were observed within the vitreous representing haemorrhage, vitreous degeneration or detachment. The B-mode ultrasonographic imaging technique has become an essential diagnostic tool in most ocular disease. This method provides additional information allowing the clinician to offer more accurate diagnosis, treatment and prognosis in glaucoma.  相似文献   
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