By using effective chiral Lagrangians with a suitable incorporation of the scaling property of QCD, we establish the approximate in-medium scaling law, ${\mathit{m}}_{\mathrm{\ensuremath{\sigma}}}^{\mathrm{*}}$/${\mathit{m}}_{\mathrm{\ensuremath{\sigma}}}$\ensuremath{\approxeq}${\mathit{m}}_{\mathrm...