ISSN:0009-7330    

出版商:OVID    

年代:1958

数据来源: OVID

摘要:

Unilobar injection of starch solution produced pulmonary infarction at the site of injection and diffuse bilateral pulmonary edema. The predominantly or entirely unilobar distribution of the embolizing material was established by histologic methods and by a technic using whole lung lobe suspension stained with Lugol's solution. Evidence is presented suggesting that the pulmonary edema in the nonembolized lobes is attributable to neural or neurohumoral mechanisms.

ISSN:0009-7330    

出版商:OVID    

年代:1958

数据来源: OVID

摘要:

The hemodynamic effects of acute hypoxia upon the pulmonary circulation were studied in dogs. The most striking changes were observed on the venous side of the circuit, consisting of a rise in venous (and arterial wedge) pressure greater than that in the pulmonary artery and an increase in the pressure gradient between the venules and the left atrium. These alterations are discussed and interpreted in an attempt to further clarify the response of the pulmonary circulation to hypoxia. It is suggested that there is arteriolar dilatation associated with increased postcapillary vascular resistance.

ISSN:0009-7330    

出版商:OVID    

年代:1958

数据来源: OVID

摘要:

An investigation was made of the possible release from heart muscle of substances of small molecular weight following experimental myocardial infarction. These resulting chemical changes in coronary vein blood may be due to metabolic alterations of the cell which would either precede cell death or take place in cells with reversible metabolic changes. The coronary arteriovenous differences of pyridine nucleotides, thiamine and its phosphorylated derivatives, amino acids and amino sugars were investigated. No changes from the control were found. The negative results may have been caused by the rapid turnover of these substances in blood.

ISSN:0009-7330    

出版商:OVID    

年代:1958

数据来源: OVID

摘要:

To know where given amounts of blood might be, we need to know the potential vascular space and what the distribution among various sized vessels is. Methyl methacrylate was injected via the cannulated aorta into 4 rats, and vascular casts made. Polymerization caused 15 per cent shrinkage. The casts were separated into 3 compartments: 150 μ. and smaller, 150 to 600 μ., and 600 μ. and larger. Using the shrinkage, specific density, and weights of plastic, the “total vascular spaces” in cc./100 Gm. were found to be 8.9, 10.6, 11.1 and 11.1, respectively. The mean percentages for the 3 compartments were 10.4 in vessels 706 μ and larger, 6.7 in 188 to 706 μ., and 82.9 in vessels 188 μ. and smaller. Because the only observed distortions of the casts on the basis of comparisons with the in vivo vasculature of a number of organs were some noninjected capillaries and nonmaximally injected veins, the approximations of “total vascular space” are considered too low. The utility of methyl methacrylate casts for gravimetric determinations of volumes was demonstrated. The finding of over 80 per cent of the vascular space in vessels 188 μ. and smaller is relevant to the potential location of blood within the body.

ISSN:0009-7330    

出版商:OVID    

年代:1958

数据来源: OVID

摘要:

Comparison of the antegrade and retrograde (collateal) coronary free flows showed that the retrograde flow was less than 10 per cent of the antegrade flow in 48 per cent of animals and above 20 per cent in 11 per cent of animals.

ISSN:0009-7330    

出版商:OVID    

年代:1958

数据来源: OVID

摘要:

A method is reported which permits the estimation of the time-course of backflow velocity in the descending aorta of patients with insufficiency of the aortic valve. Instantaneous back-velocities in excess of 100 cm./sec. have been observed. Evidence suggesting the existence of an oscillation in aortic flow during diastole in some patients is presented. An index to the “volume of backflow per stroke” is described.

ISSN:0009-7330    

出版商:OVID    

年代:1958

数据来源: OVID

摘要:

Amplification of carotid sinus activity of a dog is brought about through the use of an electric analog of the carotid sinus applied in parallel with this element of the dog's own pressure regulating system. Sinusoidal excursions in arterial pressure in response to corresponding variations, between fixed limits, in rate of stimulus of one vagus nerve were larger with carotid sinus amplification than without it. Evidence presented supports the concept that because of the delay in the response of arteriolar smooth muscle, effective buffering of sudden variations in arterial pressure cannot be accomplished by variations in resistance, but can be through variations in flow.

ISSN:0009-7330    

出版商:OVID    

年代:1958

数据来源: OVID

摘要:

Capillary ultramicroelectrodes were inserted into ventricular muscle fibers of dogs in ventricular fibrillation and action potentials obtained were compared with deflections of unipolar direct lead, adjoining bipolar direct lead or other electrocardiograms taken simultaneously. In most stages of ventricular fibrillation neither synehronism nor any other regular time relationship could he found between them. Microelectrodes inserted at two points variously distant on various regions of the ventricular surface also failed to show any regular time relationship. Total incoordination of ventricular muscle fibers was thus supported.

ISSN:0009-7330    

出版商:OVID    

年代:1958

数据来源: OVID

摘要:

Application of hemodialysis to dogs has been complicated by an acute reaction consisting of hypotension, bradycardia and respiratory depression followed by instability and a mortality rate of about 30 per cent. This reaction appears to be a response to homologous blood used to fill the dialyzers. Sensitization occurs in survivors, and accentuated reactions with marked hemolysis are noted on subsequent challenge. Cross matching the donor and recipient bloods has not permitted an adequate determination of compatibility under the conditions of hemodialysis. Satisfactory hemodialysis may be accomplished in dogs by using autogenous blood or blood substitutes to fill the dialyzers.

ISSN:0009-7330    

出版商:OVID    

年代:1958

数据来源: OVID