Scattering, RadiationHepatocyte Growth FactorAir MicrobiologyAerosol PropellantsNebulizers and VaporizersPhantoms, ImagingProto-Oncogene Proteins c-metParticle SizeAdministration, InhalationGamma CamerasAcid RainAtmosphereCone-Beam Computed TomographyInhalation ExposureHumidityTomography, Emission-Computed, Single-PhotonLungTechnetiumEquipment DesignAir MovementsMonte Carlo MethodImage Processing, Computer-AssistedArtifactsSulfuric AcidsPowdersTechnetium Tc 99m PentetateAir Pollutants, OccupationalModels, StructuralFiltrationSmogLightEnvironmental MonitoringRadiographic Image EnhancementAir PollutantsFlow CytometryGermaniumNasal SpraysPhotonsRespiratory Protective DevicesReproducibility of ResultsEquipment Failure AnalysisTechnology, RadiologicRadionuclide ImagingAlgorithmsBeclomethasoneMetered Dose InhalersAlbuterolMeteorologyRadiometryVentilationParticulate MatterSensitivity and SpecificityTomography, Emission-ComputedDry Powder InhalersRadiographic Image Interpretation, Computer-AssistedBronchodilator AgentsX-RaysChlorofluorocarbonsComputer SimulationTime FactorsRespiratory SystemAsthmaSubtraction TechniqueContainment of BiohazardsCromolyn SodiumAtmosphere Exposure ChambersDioctyl Sulfosuccinic AcidModels, TheoreticalImage EnhancementDogsDustRadiation DosageWindOccupational ExposureReceptor Protein-Tyrosine KinasesPhotomicrographyCell MovementCoughThallium RadioisotopesRespiratory TherapyAir ConditioningRadiopharmaceuticalsLaboratory InfectionAir Pollution, IndoorThreshold Limit ValuesPentanesKryptonSodium Pertechnetate Tc 99mModels, BiologicalBiological Warfare AgentsCopying ProcessesModels, AnatomicMucociliary ClearanceMasksFenoterolSootGalliumIndustrial OilsCalibrationScintillation Counting