We establish an existence result of positive solutions to the following boundary value problem:where is a bounded C 1;1 -domain in R n ,˛1;˛2 < 1 and a 1 ; a 2 are nonnegative functions in C loc . /, 0 < < 1, satisfying some appropriate assumptions related to Karamata regular variation theory. We give estimates on such solutions where appear the combined effects of singular and sublinear terms in the nonlinearity.