$$\int_0^\infty\dfrac{x^{m-1}e^{-qx}}{(\sqrt{1+px})^{m-0.5}}dx$$
$$=\int_0^\infty x^{m-1}(1+px)^\frac{1-2m}{4}e^{-qx}~dx$$
$$=\int_0^\infty\left(\dfrac{x}{p}\right)^{m-1}(1+x)^\frac{1-2m}{4}~e^{-\frac{qx}{p}}~d\left(\dfrac{x}{p}\right)$$
$$=\int_0^\infty\dfrac{x^{m-1}(1+x)^\frac{1-2m}{4}~e^{-\frac{qx}{p}}}{p^m}dx$$
$$=\dfrac{\Gamma(m)U\left(m,\dfrac{2m+5}{4},\dfrac{q}{p}\right)}{p^m}$$