These experiments were designed to study the effects of vasoactive drugs on normal and malignant tissue in W/Fu rats. The increase in resistance to tumor blood flow elicited by a bolus injection of 10 microgram of norepinephrine was greater than that elicited in the surrounding mammary gland tissue. A 10-fold increase in the resistance to tumor blood flow was sustained for 30 min by the infusio...

The flow of blood in narrow arteries with bell-shaped mild stenosis is investigated that treats blood as non-Newtonian fluid by using the K-L model. When skin friction and resistance of blood flow are normalized with respect to non-Newtonian blood in normal artery, the results present the effect of stenosis length. When skin friction and resistance of blood flow are normalized with respect to N...

INTRODUCTION Some types of antenatal maternal psychological distress may be associated with reduced fetal growth and birthweight. A stress-mediated reduction in placental blood flow has been suggested as a mechanism. Previous studies have examined this using ultrasound-derived arterial resistance measures in the uterine (UtA) and umbilical (UA) arteries, with mixed conclusions. However, a reduc...

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...

Accurate assessment of gestational age, fetal growth, and the detection of fetal and placental abnormalities are major benefits of sonography. Color Doppler can be used to assist in the identification of vascular architecture, detection of vascular pathology and visualization of blood flow changes associated with physiologic processes and disease states. The clinical applications of obstetrical...

BACKGROUND Few studies have examined the time-course of localized exercise training on regional blood flow in humans. The study examined the influence of handgrip exercise training on forearm reactive hyperemic blood flow and vascular resistance in apparently healthy men. METHODS Forearm blood flow and vascular resistance were evaluated, in 17 individuals [Age: 22.6 +/- 3.5], in both arms, at...

The role of skin and muscle vascular beds in baroreceptor-mediated alterations of peripheral vascular resistance was evaluated in six normal subjects in whom the skin circulation in one forearm was temporarily suppressed by epinephrine iontophoresis. Baroreceptor activity was enhanced by application of negative pressure to the neck (neck suction) and inhibited by application of lower body negat...

The purpose of the present study was to determine the effect of a spinal cord injury (SCI) on resting vascular resistance in paralyzed legs in humans. To accomplish this goal, we measured blood pressure and resting flow above and below the lesion (by using venous occlusion plethysmography) in 11 patients with SCI and in 10 healthy controls (C). Relative vascular resistance was calculated as mea...

To investigate the effect of alveolar hypoxia on the pulmonary blood flow-segmental vascular resistance relationship, we determined the longitudinal distribution of vascular resistance while increasing blood flow during hyperoxia or hypoxia in perfused cat lungs. We measured microvascular pressures by the micropipette servo-null method, partitioned the pulmonary vessels into three segments [i.e...