ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

Ventricular filling in the isolated right ventricle was studied. Mechanical impedance of the ventricle was estimated from simultaneous ventricular pressure and inflow measurements. Changes in work load or heart rate were accompanied by reproducible and characteristic changes in impedance and intraventricular pressure-curve contour. These were discussed in relation to changes in ventricular relaxation, elasticity, and viscosity. The right ventricle fills according to a pattern fixed by hemodynamic factors which affect the mechanical properties of the ventricle. The physical state of the ventricle early in diastole appears to be a determinant of stroke output.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

Selected inotropic drugs were studied in an isolated right ventricle preparation in which the work load and heart rate could be controlled. Records of ventricular pressure and volume were made. Rate of ventricular relaxation was estimated, and mechanical impedance to inflow was calculated as the ratio of intraventricular pressure to inflow. The negatively inotropic drugs slowed relaxation and increased impedance. Strophanthin-K reversed these effects. Adrenalin decreased impedance. It is concluded that, during the filling period, inotropic drugs alter those physical properties of ventricle wall which contribute to mechanical impedance.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

A procedure has been developed for the quantitative determination of the extractable proteins of the rat heart. Utilizing extraction with a sucrose-versene solution and employing differential centrifugation, followed by extraction with a phosphate-pyrophosphate buffer, low-ionic-strength extractives, a mitochondrial fraction, and high-ionic-strength extractives have been obtained. Electrophoretic analysis has shown five subfractions to be present in the low-ionic-strength extractives and three sub-fractions in the high-ionic-strength extractives.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

Hemidecortication usually caused arterial hypertension in rats for one or two months. Sympathicolytic drugs caused a transient reduction in blood pressure. Release of subcortical centers from the modulating action of the cerebral cortex seems to be the best explanation.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

Jet action from experimental “berry” aneurysms was evaluated as part of a long-range study of stress-strain-time relations of aneurysmal rupture. It was apparent that free jet action was a potent stress agent upon matter in its path. Calculated velocities of free jets ranged up to 477 cm. per sec. Supplementary observations were made upon jets from glass-model aneurysms, including the jet effects upon gelatin blocks cast about the models. Coefficients of velocity were determined for the various jets studied and the results were correlated with theoretic hydraulics.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

A whole blood colorimeter was developed which permits cardiac output determination after the injection of 5 to 15 mg. of Evans blue dye, resulting in maximal excursions of 5 to 11 cm. The apparatus permits sampling of blood through a cardiac catheter and its sensitivity is independent of the oxygen saturation and hematocrit of the blood sampled.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

The effect of quinidine, procaine amide and five new antiarrhythmic compounds on calcium-induced arrhythmias in the rat are described. When the compounds prevented fibrillation, the other actions of calcium on cardiac rhythm were revealed.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

Venous occlusion plethysmography was used to measure the effect of changes in limb position on the peripheral blood flow. The validity of the method with the limb dependent was investigated, and found to be reliable in the conditions of the experiment. The blood flow in the limb was found to be decreased when it was raised or lowered 45 degrees. At 15 degrees of elevation, the flow was increased. Similar changes were found in recently sympathectomized limbs. The reactions may therefore be regarded as local vascular responses to postural change.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

A method is described for estimating the quantity of blood in the leg. Experiments evaluating the accuracy and validity of the method using I131labeled human serum albumin and in vivo analysis are presented. The data suggest that in the recumbent position the leg is about 5.6 volumes per cent blood. Speculation in regard to the similarity and amount of other portions of the body to the leg lead to the possibility that about six-tenths of the blood is present in the carcass and four-tenths in the viscera.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID