Many techniques have been devised to measure the haemodynamics of the human and animal eye. In this perspective these are outlined and their use in ophthalmic investigation summarised. Some have exploited the ability of an observer to directly visualise the retinal vasculature by optical means, others have been designed to study the haemodynamics ofthe invisible parts of the eye such as the cho...

unteers were studied, nine sitting and seven supine. During hypoxia there was a slight but significant increase in relative perfusion of the upper portions of the lungs in both the sitting and supine subjects. During recovery from hypoxia, blood flow distribution differed significantly from the control. The erect subjects showed increased relative perfusion of the lung bases and the supine subj...

per tissue mass of all human organs. The resting coronary blood flow is 250 ml min 1 (0.8 ml min 1 g 1 of heart muscle); this represents 5% of cardiac output. Ischaemia results when oxygen demand outstrips supply. Arterial oxygen extraction is 70–80%, compared with 25% for the rest of the body. Therefore, increased oxygen consumption must principally be met by an increase in coronary blood flow...

In the experimental animal the basic and controversial problem was studied of the influence of cardiac contraction on coronary blood flow. Normally beating hearts were perfused at a constant pressure, and coronary inflow and outflow were determined. In order to assess the role of systole, prolonged periods of ventricular asystole and fibrillation were induced and observations were made of the c...

Background. Although aspirin exerts beneficial antiplatelet activity in patients with coronary artery disease, cyclooxygenase blockade produced by aspirin causes a potentially deleterious effect by interrupting endothelial production of prostacyclin. Collateral vessels that develop in response to coronary occlusion display prominent endothelial cell proliferation and undergo vasoconstriction in...

Background and objectives: Many clinicians believe that low-dose dopamine (LDD) [2 g/kg/min] increases renal blood flow (RBF) and medium-dose norepinephrine (MD-NE) [0.4 g/kg/min] decreases RBF. They also believe that MD-NE might induce mesenteric and/or coronary ischemia. In fact, the effects of these drugs on renal and vital organ blood flow are poorly understood. The aim of this study was to...

Background Although neurostimulation has been shown to be of benefit in angina pectoris, the exact mechanism of its action is not clear. This study was performed to examine the effect of transcutaneous electrical nerve stimulation on coronary blood flow. Methods and Results The effect of transcutaneous electrical nerve stimulation was studied in 34 syndrome X patients (group 1), 15 coronary art...

the use of flow cytometry in the clinical laboratory has grown substantially in the past decade. flow cytometric analysis provides a rapid qualitative and quantitative description of multiple characteristics of individual cells. for example, it is possible to detect the cell size and granularity, aspects of dna and rna content and the presence of cell surface and nuclear markers which are used ...

BLOOD has anomalous rheological properties, particularly in certain disease states. It may therefore be necessary to consider these properties when attempting to assess and perhaps to improve the state of a patient's cerebral circulation. So what evidence is there that cerebral blood flow (CBF) is affected by viscosity? Before attempting to answer this question, one should be aware of what infl...

Acknowledgments: The authors would like to express their gratitude to Virginia Morman, Nurse Manager of Western Nephrology Acute Dialysis, for her support of the project and to the Acute Team staff who participated in the data collection for this project. Also, thanks are extended to to Karen Chaney and Doug Reid (formerly of Gambro Healthcare) for their interest and support. W hen setting the ...