Regional Blood FlowMicrospheresBlood Flow VelocityCardiac OutputCerebrovascular CirculationHemodynamicsBlood CirculationVascular ResistanceDogsCoronary CirculationSplanchnic CirculationBlood PressureScandiumRenal CirculationLiver CirculationPulmonary CirculationLaser-Doppler FlowmetryXenon RadioisotopesHeart RateOxygenAnesthesiaBlood Gas AnalysisRadioisotopesOxygen ConsumptionNafronylNitrogen RadioisotopesTomography, Emission-ComputedBrainPhentolamineOxygen RadioisotopesVentilation-Perfusion RatioKidneySwineHindlimbCarbon DioxideMicrocirculationOrganotechnetium CompoundsVasoconstrictionPartial PressureTime FactorsImmersionModels, CardiovascularBlood VolumeIschemiaIliac ArteryRenal ArteryVasodilationPulmonary Gas ExchangeVasodilator AgentsSupine PositionHeartAnesthesia, InhalationMyocardiumNG-Nitroarginine Methyl EsterCollateral CirculationIsofluraneRats, Sprague-DawleyLegInfusions, ParenteralNitric OxideFlow CytometryMesenteric ArteriesCatsMuscle, SkeletalPropranololSympathetic Nervous SystemSheepTomography, Emission-Computed, Single-PhotonRats, WistarForearmNorepinephrineDisease Models, AnimalRats, Inbred StrainsDose-Response Relationship, DrugRabbitsNitric Oxide SynthaseInjections, IntravenousPulsatile FlowMagnetic Resonance ImagingReference ValuesCoronary VesselsLungArteriesMyocardial ContractionCapillariesEnzyme InhibitorsBlood DonorsMyocardial InfarctionCoronary DiseaseAnoxiaRheologyHyperemiaUltrasonography, DopplerXenonBlood Circulation TimeGene FlowUltrasonography, Doppler, ColorPosturePlethysmographyCerebral Arteries