  It is shown that in resistive nanowires out of equilibrium containing either
single- or two-channel Kondo impurities the distribution function $f(E,U)$
obeys scaling behavior in terms of the quasiparticle energy $E$ and the bias
voltage $U$. The numerically calculated $f(E,U)$ curves explain quantitatively
recent experiments on Cu and Au nanowires. The systematics of the impurity
concentration c_{imp} extracted from the comparison between theory and results
on various Cu and Au samples strongly suggests that in these systems the
scaling arises from magnetic Kondo impurities.
