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Although pulmonary arteriovenous malformations (PAVM) are relatively rare in children, they are important in the differential diagnosis of common pulmonary problems, such as hypoxemia, hemoptysis and dyspnea on exertion. We report the cases of two PAVM patients with different presentations and describe the treatment strategies.  相似文献   
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The main purpose of this study was to investigate the relation between carotid intima-media thickness (CIMT) and coronary artery disease (CAD) complexity. Consecutive patients (n = 360) with CAD confirmed by coronary angiography were enrolled. Mean CIMT and the overall SYNTAX score (SXscore) were 0.87 ± 0.12 mm and 15 ± 9, respectively. In univariate analysis, there was a significant correlation between the overall SXscore and CIMT (r = .42, P < .001), age (r = .23, P < .001), hypertension (r = .27, P = 0.001), diabetes (r = 0.11, P = 0.02), smoking (r = .24, P = .01), dyslipidemia (r = .2, P = 0.03), and β-blocker use (r = .19, P < .001). In multivariate analysis, CIMT (β = .34, P < .001) and age (β = .11, P < .019) were independently associated with SXscore. We have demonstrated a significant relation between CIMT and SXscore. Although this study is correlative and no causative conclusions can be drawn, our findings suggest that increased CIMT could reflect complex coronary artery lesions.  相似文献   
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Polysulfone (PSF) was prepared under high shear in a vortex fluidic device (VFD) operating in confined mode, and its properties compared with that prepared using batch processing. This involved reacting the pre-prepared disodium salt of bisphenol A (BPA) with a 4,4′-dihalodiphenylsulfone under anhydrous conditions. Scanning electron microscopy (SEM) established that in the thin film microfluidic platform, the PSF particles are sheet-like, for short reaction times, and fibrous for long reaction times, in contrast to spherical like particles for the polymer prepared using the conventional batch synthesis. The operating parameters of the VFD (rotational speed of the glass tube, its tilt angle and temperature) were systematically varied for establishing their effect on the molecular weight (Mw), glass transition temperature (Tg) and decomposition temperature, featuring gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA) respectively. The optimal VFD prepared PSF was obtained at 6000 rpm rotational speed, 45° tilt angle and 160 °C, for 1 h of processing with Mw ∼10 000 g mol−1, Tg ∼158 °C and decomposition temperature ∼530 °C, which is comparable to the conventionally prepared PSF.

Polysulfone (PSF) was prepared under high shear in a vortex fluidic device (VFD) operating in confined mode. This involved reacting the pre-prepared disodium salt of bisphenol A (BPA) with a 4,4′-dihalodiphenylsulfone under anhydrous conditions.  相似文献   
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PurposeTo describe headaches in patients with epilepsy and try to identify relations between epileptic seizures and headaches.MethodsCross-sectional study, with 304 patients from the epilepsy out-patient section of University Hospital of Federal University of Alagoas (Brazil) between February 2007 and February 2008. The presence of headaches and their relationships with the epileptic seizures were analyzed.ResultsFrequent seizures were associated with a greater tendency of occurrence of headaches (odds ratio = 1.6 times, p = 0.077). Headaches occurred in 66.1% of the cases. The highest occurrence was of migraine (32.9% of the patients), followed by tension-type headaches (9.2%). Two syndromes with a continuum epilepsy–migraine in the same seizure are worth mentioning: migralepsy in 6.6% and epilepgraine in 10.2% of the patients with epilepsy.ConclusionsA high prevalence of headaches in patients with epilepsy was observed, with emphasis on hybrid crises of epilepsy and migraine.  相似文献   
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