In an acute experiment in Texel ewes, Doppler flow velocity waveforms from the fetal descending aorta were related to peripheral vascular resistance as calculated from perfusion pressure divided by electromagnetically measured volume flow in the descending aorta. Vascular resistance was increased by stepwise embolization of the peripheral circulation via repeated bolus administration of Sephade...

background and objective: vascular endothelial growth factor (vegf) and its receptors (vegf-r1 and r2) are major regulators of angiogenesis. this study was designed to assess serum levels of vegf and vegf-r1 and their prognostic significance in newly diagnosed childhood acute leukemia. materials and methods: for this purpose, vegf and vegf-r1 were determined using enzyme linked immuno-sorbant a...

Background. Although postprandial hypotension is a common cause of falls and syncope in elderly persons and in patients with autonomic insufficiency, the pathophysiology of this disorder remains unknown. Methods and Results. We examined the hemodynamic, splanchnic blood pool, plasma norepinephrine (NE), and heart rate (HR) power spectra responses to a standardized 400-kcal mixed meal in 11 heal...

1. The effects of acute volume expansion on vascular resistance and reactivity to noradrenaline and angiotensin I1 are reported in this study. The estimated circulating blood volume of pentobartibal-anaesthetized dogs was expanded by about 35% with equilibrated donor blood. The animals were bilaterally nephrectomized to sustain expanded volume. 2. Functional changes in vascular smooth muscle we...

Present study was conducted with the objectives of determining the renal vascular resistance in dogs with diabetes mellitus and to study the correlation between the indices of renovascular resistance with glycemic status, systolic blood pressure (SBP) and proteinuria in dogs with diabetes mellitus. This study was conducted on seventeen diabetic dogs and ten apparently healthy dogs. Increa...

The purpose of this study was to test the hypothesis that regional brain blood flow and vascular resistance are altered by acute and chronic head-down tail suspension (HDT). Regional cerebral blood flow, arterial pressure, heart rate, and vascular resistance were measured in a group of control rats during normal standing and following 10 min of HDT and in two other groups of rats after 7 and 28...

Previous experiments have demonstrated that the vestibular system contributes to regulating sympathetic nervous system activity, particularly the discharges of vasoconstrictor fibres. In the present study, we examined the physiological significance of vestibulosympathetic responses by comparing blood flow and vascular resistance in the forelimb and hindlimb during head-up tilt from the prone po...

To study the resistance to standard dosage of clopidogrel among Iranian patients following percutaneous coronary intervention measured by platelet aggregation test.Patients undergoing percutaneous coronary intervention in Imam Hussein Medical center, Tehran, Iran, who were under treatment with aspirin, but had no history of clopidogrel usage, entered the study. Patients received standard dosage...

To study the resistance to standard dosage of clopidogrel among Iranian patients following percutaneous coronary intervention measured by platelet aggregation test.Patients undergoing percutaneous coronary intervention in Imam Hussein Medical center, Tehran, Iran, who were under treatment with aspirin, but had no history of clopidogrel usage, entered the study. Patients received standard dosage...

Studies were performed to determine whether an alteration in coronary vascular resistance and a reduction in the reflow phenomenon occurred in the blood-perfused, heparinized canine heart after various periods of myocaridal ischemia. Regional myocardial blood flow was measured with radioactive microspheres. Proximal left anterior descending coronary artery blood flow was measured with a periart...