How to avoid nested loops when taking portions of a matrix(e.g using every 10x10 matrix in a 100x100 matrix)?

I am interested in running several operations in every 10x10 matrix in a 100x100 matrix. How do I avoid nested loops here? For example,

    A = rand(100,100);
    B = rand(10,10);
    C = zeros(91,91);
    for i = 1:91
        for j = 1:91
            D = B .* A(i:i+9,j:j+9);
            C(i,j) = sum(D(:));
        end
    end

Answer 1

[Ahmet Cecen]

C = imfilter(A,B);