This study experimentally investigates the relationships between central cardiovascular variables and oxygen uptake based on nonlinear analysis and modeling. Ten healthy subjects were studied using cycleergometry exercise tests with constant workloads ranging from 25 Watt to 125 Watt. Breath by breath gas exchange, heart rate, cardiac output, stroke volume and blood pressure were measured at ea...

OBJECTIVE To examine cardiovascular response as a function of children's aggression after controlling for the effects of known risk factors. METHOD Participants were 140 children in second, fourth, and sixth grades. Teachers completed the Matthews Youth Test for Health, a measure that includes questions pertaining to children's aggression. Measures of blood pressure and heart rate were obtain...

Systemic vascular pressure in vertebrates is regulated by a range of factors: one key element of control is peripheral resistance in tissue capillary beds. Many aspects of the relationship between central control of vascular flow and peripheral resistance are unclear. An important example of this is the relationship between hypoxic response in individual tissues, and the effect that response ha...

artemisia species, growing in almost all the northern hemisphere, is used in folk medicine of some countries as a remedy for hypertension. since some cardiovascular disorders including hypertension are accompanied with altered responsiveness of vascular alpha-adrenergic receptors, the effect of aqueous artemisia annua extract (100 and 200 mg kg-1) on a1-adrenoceptor agonist-induced contraction ...

angiotensin-converting enzyme (ace) inhibitors including quinapril could exert a protective effect on cardiovascular system through endothelial system in normoglycemic and diabetic rats. the present experimental work was designed to study the vascular reactivity of aortic ring segments isolated from streptozotocin (stz)-diabetic rats treated for 4 weeks with nitro-l-arginine-methyl ester (l-nam...

Psychological stress elicits increases in sympathetic activity accompanied by a marked cardiovascular response. Revealing the relevant central mechanisms involved in this phenomenon could contribute significantly to our understanding of the pathogenesis of stress-related cardiovascular diseases, and the key to this understanding is the identification of the nuclei, pathways and neurotransmitter...

The immediate-early gene product and zinc finger transcription factor early growth response (Egr)-1 plays a key master regulatory role in multiple cardiovascular pathological processes. This article reviews the amazing recent evidence implicating Egr-1 in atherosclerosis, intimal thickening after acute vascular injury, ischemic pathology, angiogenesis, allograft rejection, and cardiac hypertrophy.

An instrument, the AGS (artificial gravity simulator), has been built to produce artificial gravity. This paper reports preliminary results of experiments on human subjects conducted to study the cardiovascular response to various g-levels and exposure times.