GanciclovirAntiviral AgentsThymidine KinaseCytomegalovirus InfectionsCytomegalovirus RetinitisCytomegalovirusFoscarnetAcyclovirGenetic TherapySimplexvirusGenes, Transgenic, SuicideProdrugsRetinitisPhosphotransferases (Alcohol Group Acceptor)Herpesvirus 1, HumanGenetic VectorsOrgan TransplantationGliosarcomaBystander EffectAIDS-Related Opportunistic InfectionsOrganophosphonatesAdministration, OralAntimetabolitesTransplantation, HomologousViremiaAdenoviridaeInjections, IntravenousCytosineDrug Resistance, ViralRibonucleosidesVitreous BodyDNA, ViralOrganophosphorus CompoundsAcquired Immunodeficiency SyndromeDrug ImplantsBone Marrow TransplantationTumor Cells, CulturedGene Transfer TechniquesOpportunistic InfectionsDimercaprolTransduction, GeneticHerpesvirus 6, HumanPneumonia, ViralTransplantation