Directed Tissue DonationTissue DonorsClergyTissue and Organ ProcurementUnited States Office of Research IntegrityThird-Party ConsentDeltaretrovirus InfectionsDeltaretrovirus AntibodiesTissue BanksNucleic Acid Amplification TechniquesOocyte DonationFamilyLiverBlood DonorsDecision MakingLiver NeoplasmsLiving DonorsLiver DiseasesLiver TransplantationLiver Cirrhosis