OxygenDyspneaOxygen ConsumptionMagnetic Resonance ImagingBlood Gas AnalysisOximetryReactive Oxygen SpeciesBrain MappingCarbon DioxidePartial PressureOxygen Inhalation TherapyBlood PressureCerebrovascular CirculationBrainImage Processing, Computer-AssistedAnoxiaHeart RateHemodynamicsHemoglobinsOxyhemoglobinsHypercapniaPulmonary Disease, Chronic ObstructiveRegional Blood FlowRespiratory Function TestsRestTime FactorsArteriesSinglet OxygenBlood Flow VelocityExercise ToleranceRespirationBoidaeApneaDivingRespiratory InsufficiencyForced Expiratory VolumeDogsAnesthesiaUrological AgentsVisual CortexLung Diseases, ObstructiveDiphosphoglyceric AcidsGyrus CinguliPhotic StimulationSeverity of Illness IndexImage Interpretation, Computer-AssistedCerebral CortexEcho-Planar ImagingTomography, OpticalDyspnea, ParoxysmalExercise TestNerve NetReproducibility of ResultsHydrogen-Ion ConcentrationAnalysis of VarianceHematocritSpirometryPulmonary Gas ExchangeVascular ResistanceLungSpectroscopy, Near-InfraredVital CapacityCardiac OutputElectroencephalographyRats, Sprague-DawleyTreatment OutcomeFrontal LobeRespiratory MusclesOxygen IsotopesHypotensionPrefrontal CortexRespiratory MechanicsEvoked Potentials, VisualSomatosensory CortexSensitivity and SpecificityNeural PathwaysArtifactsArterial PressurePerfusion ImagingModels, Cardiovascular