Parametros (from the Greek. para - about + necrosis) - initial reversible phase denaturation cellular proteins that occur under the influence of various factors - heat, cold, radiant energy, acids, alkalis, drugs, etc., Characteristic of parametros is its nespecificescoe: regardless of the nature of the stimulus changes when parametrize always the same and are to decrease in the degree of dispersion of colloids cytoplasm and nucleus, the shift reaction of nucleus and cytoplasm acidic side, the suppression of granulozitopenia and diffuse the colouring of the nucleus and cytoplasm lifetime dyes, increase of viscosity of colloids cells and the release of the latest ions of potassium, phosphate, and the accumulation of ions of sodium and chlorine. After the termination of the pathogenic influence the structure and function of cells regenerate, which radically distinguishes parametros from necrosis (see) and explains the name of this condition, given A. N. Nasonova and C. Y. Alexandrov. Electron microscopic studies show that when P. reversible changes are and ultrastructure of cells, the mitochondria, endoplasmic reticulum, Golgi apparatus, etc.