  Since large $p_T$ particles in high-energy hadronic or nuclear collisions
come from jet fragmentation, jet quenching due to parton energy loss in dense
matter will cause the suppression of large $p_T$ hadron spectra in high-energy
heavy-ion collisions. Assuming an effective energy loss $dE/dx$ for the high
$E_T$ partons, effective jet fragmentation functions are constructed in which
leading hadrons will be suppressed. Using such effective fragmentation
functions, high $p_T$ hadron spectra and particle suppression factors relative
to $pp$ collisions are estimated in central high-energy nuclear collisions with
a given range of the assumed $dE/dx$. It is found that the suppression factors
are very sensitive to the value of the effective energy loss. Systematic
nuclear and flavor dependence of the hadron spectra are also studied.
