Radioactivity in the effluents from high-speed liquid chromatographic analyzers was continuously measured by use of a new sample segmentation system. To achieve highest counting efficiency, the column effluents were mixed with scintillation fluid carrying small segments of semisolid, resillient spacer. After passing through a mixer, the mixture was passed through a hollow-tube flow cell mounted...

background: the present research has focused on the effect of radioactivity on drinking water from five sites in the region of zahedan city. materials and methods: the measurement of water activity in wells, river and spring has been used as a screening method. the determination of gamma emitters was performed by use the application of gamma spectrometry. results: the values of radium concentra...

The distribution of 3-hydroxykynurenine, a tryptophan metabolite that is suspected of being carcinogenic, was studied in mice. After s.c. administration of [3H]-3-hydroxykynurenine into male BALB/c X DBA/2 F1 mice, the distribution of 3H was investigated by whole-body autoradiography and radioactivity measurement. At 30 and 60 min after injection, 3H was distributed mainly in the kidneys, pancr...

The specific radioactivity of free leucine has been measured in rat liver at various times after the injection of labeled leucine. The results of these measurements have served to calculate the effect of leucine reutilization on a previous measurement of the apparent turnover rate of catalase with labeled leucine as precursor. This effect was found to account entirely for the difference between...

This report describes the construction and performance characteristics of a device capable of making rapid serial measurement of rat brain radioactivity following the administration of a positron emitting isotope. Two bismuth germanate oxide (BGO) scintillation detectors in a coincidence detection circuit are used to achieve the necessary degree of collimation. Data from the device can be used ...

The absorption of vitamin B(12) following the simultaneous administration of (58)Co B(12) and a complex of (57)Co B(12) with human gastric juice was assessed by measurement of urinary excretion of radioactivity. Sixteen control subjects, 13 patients with pernicious anaemia, and four who had had total gastrectomy were studied. The method proved a reliable means of detecting those with intrinsic ...

Among the current activities of the IAEA laboratory is a project for the measurement and analysis of small amounts of radioactivity in living persons. This is done with what is known as a "whole body counter" installed in the basement of the Agency's headquarters building in Vienna. This facility is also available for rendering services to Member States at their request as part of the bio-assay...

We investigated factors affecting sensitivity and reproducibility of radioenzymic (catechol-O-methyltransferase) measurement of plasma catecholamines. There was no apparent deterioration of catecholamine during storage at -20 degrees C for 240 days. Accuracy and sensitivity of the assay depended mostly on the method of transferase preparation; its preparation by adjusting the pH to 6.8 before f...

The measurement of radioactivity deposited in the lung is often performed with an array of germanium detectors placed over the chest of the individual. The detector array size can be from four to eight detectors depending on the size of the germanium detector and Dewar assembly. Typically, large area diameter germanium detectors (70 mm diameter) consist of four detectors, and the larger arrays ...