[en] The preasymptotic behaviour of elastic nucleon-nucleon amplitudes is studied in the limit of high-energy large-angle quasipotential scattering. Formulae obtained are used for a common description of experimental data on the differential cross sections of pp and pn elastic scattering. It is concluded that preasymptotic effects in nucleon-nucleon large-angle scattering are characteristic in the energy range where the hadron dynamics is dominated by the interaction of point-like constituents of hadrons at short distances