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Polycrystalline samples of Ru(Sr2are synthesized to study the e ects of La doping on the superconducting and magnetic properties of the Ru-1222-type compound which is a ferromagnetic superconductor. We nd that, in contrast to the studies on Ru(Sr2there is no indication of an increase in the magnetic ordering temperature when La is substituted for Sr in the Ru(Sr2Cu2Oz system. However, increasing the La content has the e ects of increasing the normal state resistivity and slightly decreasing the Tc. These features are also observed for the (Ru0:5Nb0:5)(Sr2Cu2Oz system, in which the Nb substitution for Ru signi cantly reduces the ferromagnetic component of the magnetization, suggesting that the La-doping e ects on superconductivity are insensitive to the magnetic ordering of Ru ions.