  We study the nuclear parton distribution functions on the basis of our
recently developed semi-microscopic model, which takes into account a number of
nuclear effects including nuclear shadowing, Fermi motion and nuclear binding,
nuclear meson-exchange currents, and off-shell corrections to bound nucleon
distributions. We discuss in detail the dependencies of nuclear effects on the
type of parton distribution (nuclear sea vs valence), as well as on the parton
flavor (isospin). We apply the resulting nuclear parton distributions to
calculate ratios of cross sections for proton-induced Drell-Yan production off
different nuclear targets. We obtain a good agreement on the magnitude, target
and projectile $x$, and the dimuon mass dependence of proton-nucleus Drell-Yan
process data from the E772 and E866 experiments at Fermilab. We also provide
nuclear corrections for the Drell-Yan data from the E605 experiment.
