MuromegalovirusCytomegalovirusCytomegalovirus InfectionsRats, Inbred WFSalivary GlandsHerpesviridae InfectionsViral ProteinsRats, Inbred LewDNA, ViralHeart TransplantationGenes, ViralTransplantation, HomologousSpleenVirus ReplicationMolecular Sequence DataBase SequenceRNA, ViralCloning, MolecularAmino Acid Sequence