  Within the framework of the minimum quadratic Poincare gauge theory of
gravity in the Riemann-Cartan spacetime we study the influence of gravitational
vacuum energy density (a cosmological constant) on the dynamics of various
gravitating systems. It is shown that the inclusion of the cosmological term
can lead to gravitational repulsion. For some simple cases of spatially
homogeneous cosmological models with radiation we obtain non-singular solutions
in form of elementary functions and elliptic integrals.
