  In medium T-matrix calculations for symmetric nuclear matter at zero and
finite temperatures are presented. The internal energy is calculated from the
Galitskii-Koltun's sum rule and from the summation of the diagrams for the
interaction energy. The pressure at finite temperature is obtained from the
generating functional form of the thermodynamic potential. The entropy at high
temperature is estimated and compared to expressions corresponding to a
quasiparticle gas.
