Stem CellsAdult Stem CellsHematopoietic Stem Cell TransplantationEmbryonic Stem CellsHematopoietic Stem CellsStem Cell TransplantationTransplantation, HomologousCell DifferentiationTransplantation, AutologousTransplantationHematologic NeoplasmsGraft vs Host DiseaseTissue DonorsKidney TransplantationCytomegalovirus InfectionsTransplantation ConditioningGraft SurvivalImmunocompromised HostPeripheral Blood Stem Cell TransplantationBone Marrow TransplantationTreatment OutcomePluripotent Stem CellsOpportunistic InfectionsHistocompatibility TestingGraft RejectionMycosesStem Cell NicheRetrospective StudiesTransplantsAspergillosisTime FactorsRoseolovirus InfectionsNeural Stem CellsHistocompatibilityMesenchymal Stem Cell TransplantationImmunosuppressive AgentsInduced Pluripotent Stem CellsCytomegalovirusHematopoietic Stem Cell MobilizationMultipotent Stem CellsRecurrenceMultiple MyelomaHeart TransplantationMesenchymal Stromal CellsStem Cell FactorTransplantation ChimeraWhole-Body IrradiationAntiviral AgentsAntifungal AgentsImmunosuppressionHematologic DiseasesCells, CulturedCyclosporineGanciclovirLeukemiaBusulfanBK VirusCord Blood Stem Cell TransplantationFatal OutcomeHerpesvirus 6, HumanOrgan TransplantationAntigens, CD34Lung TransplantationCell LineageFlow CytometryHepatic Veno-Occlusive DiseaseCell ProliferationSurvival RatePolyomavirus InfectionsSurvival AnalysisRisk FactorsPostoperative ComplicationsCombined Modality TherapyZygomycosisFollow-Up StudiesLymphoproliferative DisordersAcute DiseaseSalvage TherapyStem Cell ResearchAnemia, AplasticLiving DonorsBone Marrow CellsPlant StemsProspective StudiesFetal Stem CellsLeukemia, Myelogenous, Chronic, BCR-ABL PositiveVirus ActivationChimerismMice, Inbred C57BLIncidenceHLA AntigensTriazolesMyeloablative AgonistsTransplantation ImmunologyViral LoadCell TransplantationPrecursor Cell Lymphoblastic Leukemia-LymphomaAntineoplastic AgentsLymphocyte DepletionPolymerase Chain Reaction