  We study the hadron properties at finite temperature from measurement of the
screening masses, using two-flavor full QCD of the hybrid Monte Carlo (HMC)
algorithm with the renormalization group improved Iwasaki gauge action and the
clover improved Wilson quark action on a $16^3 \times 4$ lattice. We explore
rather heavy quark mass regions. Disconnected quark diagram is dropped. We
observe the tendency that the screening masses in all the channels degenerate,
which is in accord with the effective restoration of U$_{\rm A}$(1) symmetry,
and then eventually approach 2$\pi T$, i.e. the free quark value. In the low
temperature region below pseudocritical temperature $T_c$, the screening masses
in all the channels decrease. We discuss the different features between these
calculations and the previous ones.
