Defective VirusesMurine Acquired Immunodeficiency SyndromeVirus ReplicationHelper VirusesGenes, ViralViral ProteinsViral InterferenceRNA, ViralVaccinia virusCell LineRNA VirusesLeukemia Virus, MurineReceptors, VirusDNA, ViralMolecular Sequence DataInfluenza A Virus, H5N1 SubtypeHemagglutinin Glycoproteins, Influenza VirusInfluenza A virusInfluenza A Virus, H3N2 SubtypeVirus CultivationMutationGenetic Complementation TestBirdsSindbis VirusVirus AssemblyInfluenza A Virus, H1N1 SubtypeVirus SheddingDucksSimian virus 40Virus DiseasesGenome, ViralPlant VirusesDNA VirusesMeasles virusInfluenza A Virus, H7N7 SubtypeBase SequenceHepatitis B virusOrthomyxoviridae InfectionsInfluenza in BirdsInfluenza, HumanRabies virusViral Plaque AssayVesicular stomatitis Indiana virusOrthomyxoviridaeCercopithecus aethiopsPoultryVero CellsAvian Sarcoma VirusesAmino Acid SequenceAntigens, ViralInfluenza A Virus, H9N2 SubtypeAvian leukosis virusVirionReassortant VirusesWest Nile virusPhylogenyRespiratory Syncytial VirusesNeuraminidaseSemliki forest virusVirus ActivationAntiviral AgentsSpecies SpecificityVirus LatencySimplexvirusCapsidVirulenceFerretsChick EmbryoTemperatureAntibodies, ViralHerpesvirus 1, SuidCell Transformation, ViralGene Expression Regulation, ViralCricetinaeNeutralization TestsOncogenic VirusesSimian immunodeficiency virusSwineChickensViral Structural ProteinsParainfluenza Virus 1, HumanMumps virusHerpesvirus 1, HumanFoot-and-Mouth Disease VirusMosaic VirusesPhenotypeMutant ProteinsHepatitis A virusRecombination, GeneticEncephalitis Viruses, Tick-BorneCytopathogenic Effect, ViralAmino Acid SubstitutionMutagenesis, Site-DirectedPoultry DiseasesCells, CulturedVirus AttachmentTranscription, GeneticSerial PassageBK VirusTumor Virus Infections