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171.
The structure of cardiac rhythm was studied with the help of specialized computers during digitalization in 60 patients with atrial fibrillation of different etiology. The reduction of the heart contractions rate under digitalization is accompanied by certain changes in the structure of cardiac rhythm: the arrhythmic pattern of the ventricular contractions increases with a predominant growth of the number of long R--R intervals, the transitions from short intervals to longer ones become sharper, and portions of a relatively stable ventricular rhythm appear. Three main types of dynamics of the rhythm structure were distinguished on the basis of the changes in the interval R--R histogram. The described changes in the structure of cardiac rhythm are not specific, but when Digitalis drugs are used alone they can be used as additional criteria for digitalization.  相似文献   
172.
A retrospective analysis of 89 patients who underwent jejunoileal bypass surgery for morbid obesity disclosed 33 complications that were detected radiographically. Intestinal obstruction (10.1% of patients), cholecystitis (5.6%), renal stones (4.5%), peptic ulcer (3.4%), megacolon (6.7%), and elongation of the small intestine with hypertrophy of the mucosal folds of the jejunum (6.7%) were diagnosed solely by radiographic means.  相似文献   
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Effective pulmonary capillary blood flow was measured on the first day of life in twenty term infants with birth asphyxia and twenty-five normal term infants. The infants studied showed no clinical or laboratory evidence of respiratory distress. The mean effective pulmonary capillary blood flow of 121 ml/kg/min in the birth asphyxia group was significantly lower than the mean of 162 ml/kg/min in the normal group. The possible relationship of birth asphyxia and pulmonary hypoperfusion in the aetiology of the idiopathic respiratory distress syndrome is discussed.  相似文献   
178.
Acidosis inhibits catecholamine-induced lipolysis in vivo and in vitro. The lipolytic response of canine subcutaneous adipose tissue to short (5 min) nerve stimulations at 4 Hz was, however, not influenced by hypercapnic acidosis (pH 7.0). The steady state outflow of glycerol during a prolonged nerve stimulation at 4 Hz was inhibited by 40 per cent (p less than 0.05) at pH 7.0. Similarly, glycerol outflow during vasodilatation induced by a 4 Hz stimulation in alpha-blocked adipose tissue was inhibited by 37 per cent (p less than 0.05). Post-stimulatory glycerol outflow was, however, not influenced by acidosis. This poststimulatory glycerol outflow, which may represent a complex wash-out phenomenon, forms the largest part of the response to short nerve stimulations. It is suggested that steady state, rather than poststimulatory lipolysis should be studied in order to see the influence of treatments such as acidosis on responses to nerve stimulation.  相似文献   
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The relationships between luminal hydrostatic pressure and fluid transport by dog jejunum in vivo studied as a sheet in the Wells clamp were compared with quantitative predictions from a model proposed for the mechanism of the secretion produced by elevated venous pressure. According to the model, the secretion produced by increasing venous pressure and the secretion produced by negative luminal pressure are both passive filtrates contingent on a transepithelial pressure of a few centimeters of H2O. We consider that the agreement between the observed and predicted responses to luminal pressure provides strong support for the model. In particular, a) the observations displayed a predicted gross asymmetry in rates of fluid transfer with isotonic fluids depending on whether the luminal pressure was positive or negative; b) the observed magnitude of the negative luminal pressure required for the onset of secretion agreed with predictions; and c) the secretion contained significant amounts of protein at about 25% of the plasma concentration.  相似文献   
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