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Surgical Treatment of Atrial Septal Defect under Hypothermia   总被引:1,自引:0,他引:1       下载免费PDF全文
S. Zellos 《Thorax》1964,19(6):481-489
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Bronchial Adenoma   总被引:6,自引:6,他引:0       下载免费PDF全文
S. Zellos 《Thorax》1962,17(1):61-68
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Vitamin D status in humans depends on the amount of sun exposure and vitamin D intake. Recent reports suggest that hypovitaminosis D (as defined by serum 25-hydroxyvitamin D [25(OH)D] <10 ng/mL) is reemerging in developed countries and in the Middle East, pointing out the significance of dietary and cultural practices. In the line of prevention, we determined vitamin D status in 393 healthy preschool children randomly selected from 7 day care centers in the Municipality of Athens in October. The data for the analysis were collected from a questionnaire regarding their actual dietary practices, voluntary sun exposure, and lifestyle conditions; clinical investigation for the determination of the skin phototype; and blood sampling for the determination of serum 25(OH)D, parathyroid hormone, and osteocalcin levels. Of the 393 children, 49 were immigrants. According to our results, 6.6% of our population had serum 25(OH)D less than 10 ng/mL. Multilinear analysis showed that the amount of sun exposure and vitamin D intake were the direct determinants of vitamin D status. Immigrant children presented lower serum 25(OH)D levels associated with lower vitamin D intake and lower socioeconomic class when compared with the Greek children. No relationship was found between 25(OH)D concentration and skin phototype, whereas 93.3% of children used topical sunscreen. We suggest that abundant sunlight exposure in Athens is not sufficient to prevent hypovitaminosis D in preschool children. The extensive use of topical sunscreens and environmental factors such as air pollution would account for inadequate sunlight exposure and the need for dietary intake of vitamin D.  相似文献   
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Studies have implicated aspartame (ASP) with neurological problems. The aim of this study was to evaluate acetylcholinesterase (AChE) activity in human erythrocyte membranes after incubation with the sum of ASP metabolites, phenylalanine (Phe), methanol (met) and aspartic acid (aspt), or with each one separately. Erythrocyte membranes were obtained from 12 healthy individuals and were incubated with ASP hydrolysis products for 1 h at 37 degrees C. AChE was measured spectrophotometrically. Incubation of membranes with ASP metabolites corresponding with 34 mg/kg, 150 mg/kg or 200 mg/kg of ASP consumption resulted in an enzyme activity reduction by -33%, -41%, and -57%, respectively. Met concentrations 0.14 mM, 0.60 mM, and 0.80 mM decreased the enzyme activity by -20%, -32% or -40%, respectively. Aspt concentrations 2.80 mM, 7.60 mM or 10.0 mM inhibited membrane AChE activity by -20%, -35%, and -47%, respectively. Phe concentrations 0.14 mM, 0.35 mM or 0.50mM reduced the enzyme activity by -11%, -33%, and -35%, respectively. Aspt or Phe concentrations 0.82 mM or 0.07 mM, respectively, did not alter the membrane AChE activity. It is concluded that low concentrations of ASP metabolites had no effect on the membrane enzyme activity, whereas high or toxic concentrations partially or remarkably decreased the membrane AChE activity, respectively. Additionally, neurological symptoms, including learning and memory processes, may be related to the high or toxic concentrations of the sweetener metabolites.  相似文献   
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OBJECTIVES: We evaluated the ability of magnetic resonance imaging to perform a noninvasive assessment of coronary arteries, function and viability in one examination in a population with Kawasaki disease. BACKGROUND: Magnetic resonance angiography (MRA) can identify coronary abnormalities in patients with Kawasaki disease (KD). Contrast enhanced cardiovascular magnetic resonance (CeCMR) is the current gold standard for scar detection. Steady-state, free precession (SSFP) cine is a reliable technique to evaluate myocardial function and wall motion. METHODS: Twenty patients with KD aged 7-12 yrs, were examined. Coronary MRA was performed using a 1.5 T system with two ECG-triggered pulse sequences. CeCMR images were acquired 15 minutes after the i.v. injection of 0.1 mmol/kg Gd-DTPA using an inversion recovery sequence. SSFP cines were acquired using 6-mm short-axis slices from the atrioventricular ring to the apex. RESULTS: Aneurysms of the coronary arteries were identified in 7 patients and coronary ectasia was present in the remaining 12 patients while 1 patient had both. Transmural anterior-apical scar was detected by ceCMR in two cases, while small inferior necrosis was identified in another 2 cases. Left ventricular function was deteriorated only in the two patients with antero-apical infarction. The presence of myocardial infarction was detected in the territory supplied by the involved coronary artery. CONCLUSION: In Kawasaki disease MRA, SSFP cine and ceCMR are able to perform noninvasive coronary artery evaluation, function and infarct detection in a single study.  相似文献   
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