Cord Blood Stem Cell TransplantationFetal BloodHistocompatibility TestingBlood DonorsGraft vs Host DiseaseUmbilical CordHematopoietic Stem Cell TransplantationBlood BanksUmbilical VeinsUmbilical ArteriesInfant, NewbornAntigens, CD34PregnancyTissue DonorsHematopoietic Stem CellsSpinal CordDonor SelectionCells, CulturedSpinal Cord InjuriesMaternal-Fetal ExchangeBlood PreservationHernia, UmbilicalCell DifferentiationMesenchymal Stromal CellsTransplantation ConditioningCell SeparationBlood TransfusionUnrelated DonorsCell Culture TechniquesTransplantation, HomologousAntigens, CDStem CellsFlow CytometryColony-Forming Units AssayLiving DonorsUrachal CystHematologic NeoplasmsImmunophenotypingMice, SCIDGestational AgePlacentaGraft SurvivalAntigens, CD38Nuchal CordSeroepidemiologic StudiesMice, Inbred NODBlood Cell CountFetusADP-ribosyl CyclaseBone Marrow CellsTime FactorsLeukocytes, MononuclearWharton JellyHLA AntigensCell Lineage