background : the aim of the current study was to develop a marking technique as an internal marker to mark post blood meal mosquitoes by using stable phosphate isotope 32 p and determine the optimal concentration of it. methods : an isotonic physiological saline solution, containing different concentration of radioactive isotope 32 p-labeled disodium phosphate (na 2 h 32 po4) was injected into ...

A new isotope separator has been designed, constructed, and put into routine operation for separation of 133Xe providing a major advancement and significant cost reduction in preparation of this radioactive isotope. The design features and advantages are discussed that expedite high purity separation of relatively small quantities of this isotope. These advantages could be easily used to expedi...

W ithin a decade of the discovery of radioactivity in 1896, the chemical elements uranium, radium, polonium, and thorium were recognized as radioactive; the basic theory, mechanisms, and mathematics of radioactive decay were established; decay rates of some radioactive chemical elements were determined; and the ages of two mineral specimens were calculated for the first time from their uranium ...

1. Four different methods of calculating calcium absorption by radioactive calcium procedures have been compared with each other and with net calcium absorption in calcium-balance studies in 100 consecutive studies on 71 patients. 2. All four isotope procedures yielded highly significant correlations with net calcium absorption derived from the balance studies, but there was little to choose be...

The metabolism of iron is one of the most important subjects in the field of mineral metabolism. ,There have been numerous investigations of its problems, but until recently they have been seriously limited by the methods of study available. The production of radioactive isotopes of iron (1, 2) provided a new research tool which has proved of great value in the investigation of this field. Iron...

The metabolism of iron is one of the most important subjects in the field of mineral metabolism. ,There have been numerous investigations of its problems, but until recently they have been seriously limited by the methods of study available. The production of radioactive isotopes of iron (1, 2) provided a new research tool which has proved of great value in the investigation of this field. Iron...

The landmark experiments of Schoenheimer and Rittenberg in the 1930s provided the scientific foundation for the ensuing development and application of stable isotope techniques in clinical diagnosis and research. Stable isotopes are non-radioactive atoms of the same chemical element, which diVer only in their number of neutrons. Many elements also have radioactive (non-stable) isotopes. Aspects...

The present review discusses the advantages and limitations of using stable-isotope tracers to assess carbohydrate and fat metabolism at the whole-body level. One advantage of stable- (v. radioactive-) isotope tracers is the relative ease with which the location of a label within a molecule can be determined using selected-ion-monitoring GC-mass spectrometry (SIM-GC-MS). This technique minimize...

Synovial membranes surgically removed from the knees of 2 patients who had received radioactive yttrium-90 silicate have been examined. Autoradiographs showed that in both cases the activity was unevenly distributed over the synovium. One of the specimens, removed 7 weeks after administration of the isotope, was found to contain a slight degree of radioactivity, attributable in part to a long-l...