Polycrystalline samples of Nd1-xCaxBa2-xLaxCu3O7-δ (with 0.0≤x≤0.15) were prepared by the standard solid state method. The co-doping effect was studied on transport properties as a function of temperature and doping concentration x by thermoelectric power, S, and resistivity, ρ, measurements. The results were analyzed by Fermi liquid model. The density of states at Fermi energy, g(εF), was decreased as x increased while hole concentration in the CuO2 plane , p, was constant. The Aslamazo and Larkin (AL) model have been used for analyzing the superconducting fluctuation behavior. The excess conductivity Δσ was analyzed as a function of ε = (T-Tmf)/Tmf and results was in agreement with the theoretical prediction. This results suggested that the hole localization is the main reason of superconducting suppression in the charge neutral doped cuprates.

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