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Clearance of 5-hydroxytryptamine (5-HT) by the lungs of normal and vitamin E-deficient rats was evaluated following a 60-min exposure to 100% oxygen (O2) at 4 ATA (HBO). After exposure, lungs were isolated, ventilated, and perfused, with a recirculating system used for measurement of 5-HT clearance. Control lungs were obtained from rats exposed to air at 1 ATA. In control normal rats, fractional clearance of 5-HT was 0.78+/-0.03 (mean+/-SE). Following HBO 5-HT clearance was 0.55+/-0.04 (P less than 0.01). In control vitamin E-deficient rats. 5-HT clearance was 0.85+/-0.05 and was decreased to 0.46+/-0.03 (P less than 0.001) following HBO. To evaluate the effect of recovery time after HBO on 5-HT clearance, separate groups of rats were killed at varying intervals post-HBO. In normal rats, 5-HT clearance had returned to control levels by 3-4 after HBO; in vitamin E-deficient rats, clearance remained unchanged 4 h after HBO and was only 74% (P less than 0.001) of control values 24 h post-HBO. These results indicate that depression of pulmonary 5-HT clearance occurs in rats due to hyperoxia and is potentiated by vitamin E deficiency. This represents a reversible alteration of lung function which requires vitamin E for complete recovery. 相似文献
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Congenital complete atrioventricular block and prolapsing mitral valve are described in a 41-year-old woman who exhibited ventricular arrhythmias and symptoms initially attributed to her atrioventricular block. The importance of physical examination to elicit clues in the diagnosis of prolapsing mitral valve is emphasized. 相似文献
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EIu Dorofeeva VA Gorshkov VV Chestukhin VV Lyskovtsev AB Bezprozvanny? ED Avde?chuk GV Kesarev OM Lazutina VN Nesvetov AE Radzevich 《Canadian Metallurgical Quarterly》1997,69(8):17-19
Therapeutic and prophylactic antiarrhythmic efficacy of sotalol hydrochloride (Sotahexal, "Hexal", Germany) and its effects in intracardiac hemodynamics and ECG parameters were evaluated in 95 patients with ischemic heart disease (IHD). The highest response to the drug was observed in ventricular extrasystoles, arterial flutter and fibrillation. Acute episodes of arrhythmia are managed by bolus administration of Sotahexal [correction of Hexal]. In this case greater risk of side effects exists. It is desirable to decide on the drug dose, mode of administration on the individual basis with due consideration of the risks and dangers which could be avoided in case of adequate instrumental control. 相似文献