Regional Blood FlowMicrospheresBlood Flow VelocityCardiac OutputCerebrovascular CirculationHemodynamicsBlood CirculationVascular ResistanceDogsCoronary CirculationSplanchnic CirculationBlood PressureScandiumRenal CirculationLiver CirculationPulmonary CirculationLaser-Doppler FlowmetryXenon RadioisotopesHeart RateAnesthesiaOxygenBlood Gas AnalysisRadioisotopesNafronylOxygen ConsumptionNitrogen RadioisotopesTomography, Emission-ComputedPhentolamineVentilation-Perfusion RatioOxygen RadioisotopesKidneyBrainSwineHindlimbCarbon DioxideMicrocirculationOrganotechnetium CompoundsImmersionVasoconstrictionPartial PressureModels, CardiovascularIliac ArteryBlood VolumeRenal ArteryIschemiaVasodilationPulmonary Gas ExchangeVasodilator AgentsSupine PositionAnesthesia, InhalationTime FactorsNG-Nitroarginine Methyl EsterHeartCollateral CirculationMyocardiumIsofluraneLegInfusions, ParenteralNitric OxideMesenteric ArteriesCatsFlow CytometryRats, Sprague-DawleyPropranololTomography, Emission-Computed, Single-PhotonForearmSympathetic Nervous SystemMuscle, SkeletalSheepNorepinephrineRats, WistarRats, Inbred StrainsInjections, IntravenousNitric Oxide SynthasePulsatile FlowRabbitsDose-Response Relationship, DrugCoronary VesselsDisease Models, AnimalMagnetic Resonance ImagingReference ValuesArteriesLungMyocardial ContractionCapillariesBlood DonorsEnzyme InhibitorsMyocardial InfarctionCoronary DiseaseRheologyAnoxiaHyperemiaUltrasonography, DopplerXenonGene FlowBlood Circulation TimeUltrasonography, Doppler, ColorPlethysmographyPostureCerebral Arteries