M EIER and Zierlerl have lucidly presented the theory underlying the application of indicator dilution of the measurement of flow in the vascular bed. This theory is not violated by the presence of valve incompetence provided that indicator particles that recirculate and reenter the vascular system can be excluded from the primary indicator concentration-time curve. Valve incompetence results i...

M EIER and Zierlerl have lucidly presented the theory underlying the application of indicator dilution of the measurement of flow in the vascular bed. This theory is not violated by the presence of valve incompetence provided that indicator particles that recirculate and reenter the vascular system can be excluded from the primary indicator concentration-time curve. Valve incompetence results i...

A technic is described for determining mean circulation time, cardiac output, and central blood volume by use of graded dosages of sodium dehydrocholate (Decholin) administered into a peripheral vein. The indicator-dilution curves derived by the technic were compared with radiopotas-sium-dilution curves obtained simultaneously in 12 patients. The results showed a surprisingly good agreement bet...

Investigation of peer effects on achievement with sample survey data on schools may mean that only a random sample of peers is observed for each individual. This generates classical measurement error in peer variables, resulting in the estimated peer group effects in a regression model being biased towards zero under OLS model fitting. We investigate the problem using survey data for England fr...

BACKGROUND Despite the increasing use of real-time PCR in the diagnosis and management of viral infections, there are no published studies adequately addressing the optimum number of calibrators, the number of replicates of each calibrator, and the frequency with which calibration needs to be repeated. This study was designed to address these issues. METHODS Cycle threshold data (ABI 7700) wa...

The multiple indicator dilution technique was used to study transfer of labeled HCO3- across the hepatocyte membrane in the anesthetized mongrel dog. A bolus of H[14C]O3-, 51Cr-labeled erythrocytes, [36Cl-] and/or [3H]sucrose, and [3H]OH was injected through a catheter in the portal vein, and timed anaerobic blood samples were obtained from a catheter in the hepatic vein. Experiments were carri...

T HE shape of an indicator-dilution curve is determined by at least 4 variables: cardiac output, the volume between the injection site and the sampling site, the presence of a left-to-right intracardiac shunt, and the presence of valvular regurgitation.1-3 In the absence of an intracardiac shunt and valvular regurgitation, one can predict the downslope of the arterial dilution curve, using the ...

THE PURPOSE of this paper is to present a mathematical model of dilution curves obtained by precordial detection of concentration of an intravenously injected radioactive tracer. The analysis makes possible formulation of equations relating parameters of the curve to cofunctions of the curve, such as cardiac output, central circulating blood volume, and volume of heart chambers. The presentatio...

The volume of the primary (PCS) and secondary (SCS) circulatory system in the Atlantic cod Gadus morhua was determined using a modified dye dilution technique. Cod (N=10) were chronically cannulated in the second afferent branchial artery with PE-50 tubing. Evans Blue dye was bound to harvested fish plasma at a concentration of 1 mg dye ml(-1) plasma, and injected at a concentration of 1 mg kg(...

Plant analysis is a very promising diagnostic tool for assessment of crop nitrogen (N) requirements in perspectives of cost effective and environment friendly agriculture. Diagnosing N nutritional status of rice crop through plant analysis will give insights into optimizing N requirements of future crops. The present study was aimed to develop a new methodology for determining the critical nitr...