Abstract: This paper deals with the existence of solution for the systems u_i-K△u=F(t, x, u, ▽u) with the initial boundary value condition, where F (t, x, y, z) grows in y, z with arbitrary power and goes to infinity as t→∞. Under suitable assumptions on the nonlinear term F and the initial value condition, we will obtain a unique global solution and an asymptotic estimate.