Reverse Transcriptase InhibitorsHIV Reverse TranscriptaseDrug Resistance, ViralNucleosidesAnti-HIV AgentsHIV-1Drug Resistance, Multiple, ViralHIV InfectionsHIV Protease InhibitorsZidovudineBenzoxazinesLamivudineNevirapineHIV ProteaseGenotypeAntiretroviral Therapy, Highly ActiveViral LoadRitonavirPyrimidinonesMutationLopinavirTreatment FailureDelavirdineOrganophosphonatesAnti-Retroviral AgentsDrug Resistance, MicrobialHIVRNA-Directed DNA PolymeraseDideoxynucleosidesStavudinePurine NucleosidesRNA, ViralAdenineCD4 Lymphocyte CountDrug Therapy, CombinationDidanosineOxazinesPyrimidine NucleosidesAntiviral AgentsNucleoside Transport ProteinsZalcitabineMicrobial Sensitivity TestsMutation, MissenseDideoxynucleotidesPyridazinesPyranocoumarinsDrug ResistanceSequence Analysis, DNAMolecular Sequence DataDrug Resistance, BacterialEquilibrative Nucleoside Transporter 1Virus ReplicationDrug Resistance, MultipleNelfinavirDrug Resistance, NeoplasmThymine NucleotidesBase SequenceTreatment OutcomeReverse Transcriptase Polymerase Chain ReactionHIV Integrase InhibitorsRibonuclease HHIV-Associated Lipodystrophy SyndromeThioinosineHepatitis B, ChronicDrug InteractionsTelomeraseCohort StudiesPurine-Nucleoside PhosphorylaseCell LineAcidosis, Lacticpol Gene Products, Human Immunodeficiency VirusDeoxyadenosinesKineticsReverse TranscriptionGuanosineIndinavirDisease ResistanceSaquinavirFuransIntegrase InhibitorsHIV-2UridinePyrrolidinonesAmino Acid SequenceAcquired Immunodeficiency SyndromeInhibitory Concentration 50Nucleoside-Diphosphate KinaseVascular ResistanceInosineNitrilesRetrospective StudiesNucleotidesDrug Resistance, Multiple, BacterialMolecular StructureAnilidesPyridinesAmino Acid SubstitutionProtease InhibitorsAnti-Bacterial AgentsPyrimidines