ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

Two approaches to the analysis of spatial electrocardiographic vectors are currently being used: construction from the conventional ECG leads, and measurements from oscilloscopic recordings of spatial loops. There are several fundamental differences between the approaches, and there is noa prioricertainty that equivalent or even similar phenomena are being investigated. This study presents a statistical comparison between mean spatial vectors, constructed from the conventional ECG, and instantaneous maximum spatial vectors, determined with the stereovector electro-cardiographic technic.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

A method has been developed for the estimate of total tissue sodium by direct measurement of radiosodium concentrations in undigested samples. Accuracy is comparable to that of flame photometric estimates on tissue digests; time and cost, about one-quarter as great. The method appears particularly useful for experimental designs requiring multiple tissue sodium measurements.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

The antiarrhythmic activity of Ambonestyl in dogs with persistent ventricular tachycardia is compared with that of procaine amide. The data indicate that Ambonestyl is as effective in suppressing the arrhythmia as procaine amide, but is pharmacologically more specific since it does not depress cardiac conduction, or elevate ventricular electrical threshold, and produces less hypotension.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

The lipicl profile of connective tissue, isolated from the rat and the rabbit, by the sponge-implantation technique, is presented. This tissue is rich in cholesterol, phospholipid, and neutral fat. Several sex, age, and species differences in the concentration of its lipids are reported. Simultaneous determination of serum lipids indicates that there is no significant correlation between the lipid values of the serum and connective tissue. The relationship of these findings in connective tissue, the chief constituent of the intima, to the problem of atherosclerosis is discussed.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

Rats with polycythemia induced by exposures to simulated high altitudes developed a significantly higher incidence of endocarditis following intravenous bacterial injections than rats with cobalt polycythemia or ground level controls. No increase occurred in altitude rats when polycythemia was prevented by repeated bleedings. These findings suggest that both polycythemia and hypoxia are necessary to explain increased susceptibility of altitude rats. Cortisone increased susceptibility of ground level rats injected withStreptococcus faecalis. Unlike altitude exposures, however, cortisone did not render rats susceptible to endocarditis due toHemophilus parainfluenza.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

Variations in flow in the presence of a constant arteriovenous pressure difference can only occur when vascular dimensions have been altered, irrespective of the rheological properties of the liquid being perfused. When the vascular bed of the hind leg is subjected to parallel changes in arterial and venous pressures, higher absolute values of pressure result in an enhancement of flow. This constitutes convincing evidence to indicate that certain vessels which offer a significant resistance to blood flow are distensible.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

Splanchnic outflow was studied along with carotid and aortic presso- and chemoreceptor inflow in cats under a variety of conditions. Splanchnic activity was increased by a decrease in presso- or increase in chemoreceptor activity and vice-versa. Blood pressure rose following splanchnic activation. Protoveratrine and serotonin, reported to activate the “coronary chemoreflex,” depressed completely splanchnic outflow, without enhancing pressoreceptor activity. Prolonged hypotension from protoveratrine coincided with partial return of splanchnic activity and tonic discharge of pressoreceptors. ATP increased splanchnic activity simultaneously with the hypotension and it is suggested that it be excluded from the list of drugs eliciting the “coronary chemoreflex.”

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

The effects, in rabbits, of heparin, AMP, and ATP against both experimental cholesterol-induced atherosclerosis and epinephrine-thyroxine medial arteriosclerosis, were studied. Heparin and AMP, in general, were ineffective. Marked, statistically significant inhibition of both experimental atherosclerosis and experimental medial arteriopathy was achieved with ATP.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID

摘要:

Hemodynamic alterations were produced in dogs by injecting meningococcus toxin. Hypotension and a decrease in cardiac output occurred without significant reduction in blood volume. These changes were accentuated by small hemorrhage. Increasing the blood volume above normal led to marked increase in cardiac output with slight increase in arterial pressure. The arterial pressure was markedly increased by the administration of levarterenol but large doses were required. Cortisone did not modify the effect of meningococcus toxin on the circulation. Meningococcus toxin apparently produced its effect by increasing the volume of blood in small blood vessels.

ISSN:0009-7330    

出版商:OVID    

年代:1955

数据来源: OVID