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Progressive systemic sclerosis may be associated with focal myocardial fibrosis. Electrocardiographic abnormalities including conduction block are common in progressive systemic sclerosis but whether they are due to direct destruction of the specialized conduction tissue of the heart is uncertain. The conduction systems of 35 patients with progressive systemic sclerosis were studied. Of these 35 patients, 17 (50 per cent) had myocardial fibrosis of the type seen in progressive systemic sclerosis. In 10 of the 17, it was severe. Sinus node fibrosis was present in 13 patients and was nearly as frequent in those with as in those without the progressive systemic sclerosis myocardial lesion. Overlying pericarditis may have contributed to the fibrotic changes within the sinoatrial nodes in seven of the 13 patients. The atrioventricular node and main His bundles were normal. However, fibrotic changes were found in the proximal bundle systems in six patients. In three of the six, severe myocardial progressive systemic sclerosis was present, two had focal fibrous atrophy of the left bundle, and one had complete interruption of the right bundle. In only the latter patient was this reflected in the electrocardiogram which showed a right bundle branch block. Three patients without progressive systemic sclerosis myocardial lesions also had fibrous atrophy of a portion of the proximal left bundle branch, and in one the electrocardiogram showed an isolated left anterior hemiblock. Thus, morphologic abnormalities within the conduction system in our patients are difficult to attribute to progressive systemic sclerosis per se. Furthermore, although conduction abnormalities were more frequent in patients with myocardial disease, specific conduction system disease was not the cause in most patients. As has been noted in ischemic heart disease, the conduction system appears to be relatively spared from the myocardial changes of progressive systemic sclerosis, and the high incidence of conduction disturbances in this condition may be a consequence, rather, of damage to working myocardium.  相似文献   
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The increase of the concentration of fatty acids, the reduction in the concentration of serotonin, the lowering of the activity of glucose-6-phosphate dehydrogenase and transketolase, and the development of compensated metabolic acidosis were discovered in the stage that preceded strophanthine arrhythmia. These characteristics may be recommended for a wider use on the clinical basis for predicting arrhythmias in the treatment of cardiac glycosides.  相似文献   
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Hypoxemia (45-minute) influence in vivo on erythropoietic activity of the kidney, liver, spleen, and sternum was studied by normoxemic perfusion of the isolated organs. The erythropoietic activity proved to increase after 6-hour perfusion of the liver; this confirmed the participation of this organ in the extrarenal secretion of the erythropoietic factor.  相似文献   
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Concrements were found in the ducts of 172 patients subjected to secondary surgical interventions on bile ducts. The detailed analysis of the data failed to answer the question whether the stones could be formed immediately in the ducts without such conditions as a mechanical obstacle for the outflow of bile, the presence of foreign bodies and a big stump of the cystic duct. Such a formation of stones can take place in very few cases. The authors have shown that control cholangiography and especially choledochoscopy can reduce the danger to leave the stones in the ducts, but does not eliminate the danger completely. Nevertheless they think that now it is possible to lessen the indications for biliodigestive anastomoses in choledocholithiasis since the retained stones can be revealed within the first days after surgery and, as a rule, removed with instruments or by other methods using the drainage left in the ducts.  相似文献   
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