Airway ResistanceHeliumAirway ObstructionPlethysmography, Whole BodyLung ComplianceRespiratory MechanicsBronchoconstrictionAirway RemodelingLungRespiratory Function TestsLung Volume MeasurementsDrug ResistanceBronchoconstrictor AgentsAsthmaMethacholine ChlorideBronchial HyperreactivityBronchiRespiratory SystemDrug Resistance, MicrobialInhalationAir PressureDrug Resistance, BacterialPulmonary VentilationBronchial Provocation TestsWork of BreathingBronchodilator AgentsOxygenRhinomanometryDrug Resistance, NeoplasmIpratropiumNasal ObstructionDecompressionPlethysmographyFunctional Residual CapacityRespirationAdministration, InhalationAerosolsDecompression SicknessHistamineSpirometryTidal VolumeAlbuterolPulmonary Gas ExchangeDrug Resistance, MultipleRespiratory Physiological PhenomenaForced Expiratory VolumeRhinometry, AcousticPositive-Pressure RespirationNasal DecongestantsDisease ResistanceBronchoalveolar Lavage FluidRespiratory MusclesVascular ResistanceNoseOscillometryDrug Resistance, ViralDrug Resistance, Multiple, BacterialRespiratory HypersensitivityEpiglottisNasal Provocation TestsNasal CavityIntubation, IntratrachealBronchial SpasmBronchiolitisClemastineRespiration, ArtificialAnti-Bacterial AgentsVital CapacityMaximal Expiratory Flow-Volume CurvesMouth BreathingExhalationCroupPulmonary Disease, Chronic ObstructiveAirway ManagementPharynxRespiratory MucosaThyroid CartilageMuscle, SmoothSnoringMicrobial Sensitivity TestsTotal Lung CapacityLung Diseases, ObstructiveVentilators, MechanicalNebulizers and VaporizersForced Expiratory Flow RatesSleep Apnea SyndromesSleep Apnea, ObstructiveGuinea PigsMucusNasal MucosaRespiratory SoundsMethacholine CompoundsInspiratory CapacityTime FactorsRespiratory TherapyContinuous Positive Airway PressureCromolyn SodiumOxygen Inhalation TherapyModels, BiologicalSleep