RESUMO
An experimental unit for radiofluorescent analysis using the REIS-I x-ray emitter, a Si (Li) detector, an analyser with the NOIKA LP-4900 microprocessor and appropriate soft ware was devised for a study of some aspects of metabolism and kinetics of a number of electrolytes playing an important role in the state of water-salt homeostasis of the organism of man and animals. Methodological approaches to quantitative determination of the native content of plasma trace elements and macrocells: S, Cl, K, Ca and stable bromine administered for determination of extracellular fluid volume--were developed. This method can be used for determination of quantitative indices of the above functions in healthy men and animals during outer space flights, ground mock-up experiments, for clinical investigations in diagnosis of subpathological conditions and for control of therapeutic efficacy.