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91.
FA Amosenko VV Surkov TI Tikhonenko TS Maksimova 《Canadian Metallurgical Quarterly》1976,26(3):361-366
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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V. V. Frolov 《Journal of Engineering Physics and Thermophysics》1969,17(1):867-872
We propose a method of constructing discontinuous solutions for nonlinear problems in the theory of heat conduction. The method is a modification of the pivot methods for the solution of linear boundary-value problems. As an illustration we present numerical solutions of two problems.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 17, No. 1, pp. 111–117, July, 1969. 相似文献
98.
G. A. Frolov 《Journal of Engineering Physics and Thermophysics》2004,77(3):489-520
A model of heating and thermal destruction of a material is suggested on the basis of analysis and generalization of computationalexperimental and literature data. The fundamental importance of the constant of thermal destruction in nonstationary processes of heating and entrainment of mass and its interrelation with the heat of material evaporation are shown. The mechanism of heat absorption in the surface layer of the destructing material, which determines the time of reaching the quasistationary mode of heating and entrainment of mass, is found. The limiting power capacity of internal and surface processes of heat absorption by a heatprotective material is considered. 相似文献
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OE Kolesova LM Alekseeva LA Apollonova TM Frolova VV Ivanitskaia 《Canadian Metallurgical Quarterly》1982,45(2):59-62
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