Читать книгу The Glands Regulating Personality - Louis Berman - Страница 33

The isolation of thyroxin has made possible the determination of the influence of the thyroid hormone upon the evolution of energy in any higher animal organism. There is, for every individual, a constant, known as the metabolic rate, or the combustion rate, a reading of the rate at which his cells are consuming material for heat. The metabolic rate is thus a gauge of the energy pressure within the organism. It may be calculated by measuring the amount of carbon dioxide gas exhaled during a unit of time, and the number of calories of heat radiated by the skin simultaneously. A simplified device has lately rendered it practicable to make actual determinations by a few five-minute readings of the rate of oxygen absorption by the lungs. Plummer, also connected with the Mayo Foundation, has shown that what would amount to less than a grain of the thyroxin would more than double the amount of energy produced in a unit of time. To be exact, one milligram of thyroxin increases the metabolic rate two per cent. That illustrates some of the power of the internal secretion of the thyroid and its importance to normal life.