ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

Choline deficiency leads to lipomatous infiltration of the coronary arteries and to aortic sclerosis of the Moenckeberg type in young rats. In this form of experimental cardiovascular disease the total serum cholesterol and the triglyceride-bearing lipoproteins are decreased. The beta-lipoprotein classes are essentially within normal limits. The significance of these findings in particular and of serum lipid values in general as relating to different types of experimental cardiovascular disease is discussed.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

Circulating epinephrine and norepinephrine are avidly absorbed and stored by the heart muscle but not by skeletal muscle of dogs. Stimulation of the cardiac sympathetic nerves augments myocardial norepinephrine but not epinephrine. Sympatholytic drugs do not diminish, some even increase active catecholamines in heart muscle. The results explain a number of pathophysiologic conditions briefly enumerated.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

Various substrates were tested for their ability to restore the amplitude of contraction of hypodynamic electrically-stimulated rat ventricle strips suspended in a phosphate-buffered medium. Greatest recovery of the contractile activity was obtained with pyruvate; lactate, β-hydroxybutyrate and acetate were more effective than succinate and glucose. The finding that glucose, in contrast to pyruvate, was relatively ineffective as an energy source for contraction, when a phosphate-buffered medium was employed, suggests that the defect was due to a rate-limiting step in the conversion of glucose to pyruvate, rather than to an impairment in the functioning of the Krebs cycle.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

A time-intensity analysis of I131was carried out with a highly shielded well-collimated scintillation detector placed over the chest of normal men and women, patients and dogs. I131human serum albumin solution was injected intravenously. The curves thus obtained when analyzed for cardiac output gave values not significantly different from simultaneously obtained direct Fick values.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

Investigation of the properties of indigo carmine reveals that it may be more suitable than the dye, T-1824, for circulatory studies that are now commonly carried out using the dye dilution principle of Stewart and Hamilton. Comparison is made of simultaneous dilution curves of indigo carmine and radioactive iodinated serum albumin. Apparently, indigo carmine is bound to protein firmly enough to remain the plasma in one passage through the heart and lungs, but not too firmly to be extracted rapidly from the plasma by excretory systems in the kidney and liver. This allows repeated injections without accumulation.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

Coronary arteriovenous electrolyte differences were studied in normo- and hypercapneic dogs at normal temperature and at 24 C. The ions measured were sodium, potassium, calcium, magnesium, chloride and hydrogen. Coronary arteriovenous electrolyte differences did not change during cooling in 16 dogs which did not suffer ventricular fibrillation. Ten hypercapneic hypothermia dogs exhibited characteristic Ca, K, and H ion changes at 24 C. before succumbing to ventricular fibrillation. The data suggest that ventricular fibrillation at low body temperatures is related to a gain of Ca and a loss of K and H ions by the hypothermia hypercapneic myocardium.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

The roles of vasodilator metabolites and/or reduced local intra-arteriolar pressure in producing the reactive hyperemia which follows the sudden release of arterial occlusion were studied. It was found that slight increases of metabolic activity during the period of occlusion increased the reactive hyperemia considerably. Maintenance of intra-arteriolar pressure during arterial occlusion depressed the resultant reactive hyperemia. It was concluded that both factors contribute to the reactive hyperemia. The blood flow “debt” incurred during arterial occlusion was almost invariably “overpaid” during the reactive hyperemia period.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

A method is described whereby it is possible to obtain volume curves from theleftventricle of an open-chested dog with an essentially intact systemic circulation. Several applications of such univentricular records to the study of the heart's performance are suggested and examples of analyses from recorded curves are presented. Changes in the physicochemical properties of the myocardium are seen to accompany alterations in the chemical environment of the heart.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

Small infusions of dextran fractions having average molecular weights ranging from 10,600 to 412,000 yield plasma to lymph concentration ratios which are directly proportional to molecular weight. The concentration gradient for a specific molecular weight, however, decreases as the volume of infusion is increased. This volume effect, explained in terms of stretching of capillary pores, consequently provides less resistance to the passage of macromolecules through the capillary wall. The significance of these results in terms of the conventional pore theory of capillary permeability is discussed.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID