  The La0.7Sr0.3MnO3 (LSMO) layers and YBa2Cu3O7-{\delta}/La0.7Sr0.3MnO3
(YBCO/LSMO) bilayers were grown by magnetron sputtering on sapphire (Al2O3 or
ALO) substrates. Temperature dependences of resistance of single LSMO films,
grown on ALO substrates were typical for polycrystalline manganite materials
and the resistance decreased with decrease of the temperature at medium
temperatures and increased at lower and higher temperatures. Deposition of a
top YBCO layer led to a drastic increase of the sample resistance. These
bilayers did not demonstrate a decreasing of the resistance with decrease of
temperature. Temperature dependence of the resistance of these samples was
interpreted in the framework of a phenomenological model of two intergrain
conduction channels. In framework of this model, parameters of the samples were
determined and discussed.

Materials Science;Strongly Correlated Electrons