ISSN:0009-7330    

出版商:OVID    

年代:1953

数据来源: OVID

摘要:

Local carotid sinus application of noradrenaline induces a stimulation of the pressoceptors at different constant physiologic and nonphysiologic intrasinusal pressure ranges. Tension and resistance to stretch of the arterial wall where the pressoceptors are located, are the fundamental factors affecting, at different pressure ranges, those receptors which regulate and moderate reflexly the systemic arterial pressure.

ISSN:0009-7330    

出版商:OVID    

年代:1953

数据来源: OVID

摘要:

The application of ion-exchange chromatography for the determination of adenosine nucleotides in mammalian hearts is described. It is found that 1 gram ventricular muscle contains nearly 5 × 10-6mole of adenine nucleotides, presumably present as ATP in the relaxed heart in vivo. After isolation of the heart, breakdown of ATP takes place especially under anaerobic conditions, and the reaction products AMP and IMP diffuse into the medium. Effects upon these reactions of glucose, glutamic acid and excess potassium are suggested by preliminary experiments.

ISSN:0009-7330    

出版商:OVID    

年代:1953

数据来源: OVID

摘要:

Relaxed mammalian hearts contain ATP as the predominant nucleotide, sometimes accompanied by smaller amounts of ADP, presumably formed during manipulation. In systole, one-tenth of the nucleotide is changed into a new compound, nucleotide H.

ISSN:0009-7330    

出版商:OVID    

年代:1953

数据来源: OVID

摘要:

Vascular responses in the large central pad of the dog's foot were recorded during stimulation of the lumbosacral sympathetic trunk and correlated with the site of stimulation and the subsequent histologic analysis of the excised trunk. The resulting description of the preganglionic inflow and postganglionic outflow from the trunk demonstrated marked variations in the anatomic patterns of the vasomotor innervation of the footpad in various animals. Complete preganglionic denervation of this vascular bed required extirpation of the entire lumbar trunk caudalward as far as L-7 in addition to the interruption of those preganglionic pathways through the spinal nerves which do not pass through the sympathetic trunk.

ISSN:0009-7330    

出版商:OVID    

年代:1953

数据来源: OVID

摘要:

Blood flow of the toes and fingers was studied plethysmographically with the level of the blood vessels below or above the heart, using the contralateral digit as control. The apparent flow is a maximum when the vessels are near the heart level. The decrease of flow when the vessels are raised is explained on the basis of narrowing and closure of vessels when the hydrostatic pressure within them falls. The decrease in flow when the limb is lowered is interpreted as evidence of a vasoconstriction elicited by distension of the local veins. This raises serious doubt about the classic flow method.

ISSN:0009-7330    

出版商:OVID    

年代:1953

数据来源: OVID

摘要:

Blood flow was measured with the electromagnetic flowmeter in the saphenous artery bed (cutaneous) and in the distal femoral and popliteal beds (muscle). The effects of ischemia and of intra-arterial injection with methacholine, l-epinephrine and l-norepinephrine were studied before and again after each injection of progressively increased doses of antiadrenergic drugs. These studies indicate a fundamental difference between the reactivity of cutaneous and muscular vascular beds.

ISSN:0009-7330    

出版商:OVID    

年代:1953

数据来源: OVID

摘要:

Clinical data and hemodynamic measurements made by cardiac catheterization are presented in two patients with tricuspid stenosis of rheumatic origin. In one, pure tricuspid stenosis was proved by autopsy, and in the second the development of tricuspid stenosis and insufficiency was demonstrated by means of cardiocirculatory studies made 27 months apart. A detailed analysis of the pressure pattern characteristic of this type of valvular stenosis is given. The measurement of the stenosed tricuspid valve area by three methods is described and discussed.

ISSN:0009-7330    

出版商:OVID    

年代:1953

数据来源: OVID

摘要:

Wedged catheter pressures (PC) were compared with those in the aorta, left atrium, and pulmonary artery before and after production of mitral stenosis, insufficiency, and pulmonary embolism. In general it was found that “PC” pressures follow closely changes in left atrial pressures even when pulmonary artery pressure changes in an opposite direction (for example, pulmonary embolism). However, properly recorded “PC” pressure pulses did not display the large cyclic pressure variations recorded from the left atrium during mitral stenosis and insufficiency. It is concluded that pressures recorded through a properly wedged catheter represent the constant pulmonary capillary pressure but do not reflect cyclic pressure variations in the left atrium.

ISSN:0009-7330    

出版商:OVID    

年代:1953

数据来源: OVID

摘要:

Left and right ventricular end diastolic pressure, stroke work, stroke volume, and cardiac output were measured in open and closed chest dogs infused with blood and/or saline. The methods employed permitted repeated determinations of these factors during short time intervals. For nonfatigued hearts in the open chest preparation point to point correlation of end diastolic pressure with the other three variables was very good, but in closed chest animals a number of non-correlations occurred. Sufficient variation was seen to indicate that factors other than those measured in this study will have to be known before cardiac performance in the intact animal can be fully assessed.

ISSN:0009-7330    

出版商:OVID    

年代:1953

数据来源: OVID