Regional Blood FlowMicrospheresBlood Flow VelocityCerebrovascular CirculationCardiac OutputHemodynamicsBlood CirculationVascular ResistanceDogsCoronary CirculationSplanchnic CirculationBlood PressureScandiumRenal CirculationLiver CirculationPulmonary CirculationLaser-Doppler FlowmetryXenon RadioisotopesHeart RateOxygenAnesthesiaOxygen ConsumptionBlood Gas AnalysisRadioisotopesNafronylTomography, Emission-ComputedNitrogen RadioisotopesPhentolamineOxygen RadioisotopesVentilation-Perfusion RatioBrainKidneySwineCarbon DioxideHindlimbMicrocirculationOrganotechnetium CompoundsPartial PressureImmersionVasoconstrictionModels, CardiovascularTime FactorsBlood VolumeIliac ArteryIschemiaRenal ArteryPulmonary Gas ExchangeVasodilationVasodilator AgentsSupine PositionAnesthesia, InhalationHeartNG-Nitroarginine Methyl EsterMyocardiumCollateral CirculationLegIsofluraneInfusions, ParenteralNitric OxideMesenteric ArteriesCatsFlow CytometryMuscle, SkeletalRats, Sprague-DawleySheepTomography, Emission-Computed, Single-PhotonPropranololForearmSympathetic Nervous SystemRats, Inbred StrainsNorepinephrineRats, WistarDose-Response Relationship, DrugInjections, IntravenousRabbitsNitric Oxide SynthasePulsatile FlowCoronary VesselsDisease Models, AnimalReference ValuesMagnetic Resonance ImagingArteriesLungMyocardial ContractionUtilization ReviewCapillariesBlood DonorsEnzyme InhibitorsMyocardial InfarctionCoronary DiseaseRheologyAnoxiaGlucoseHyperemiaUltrasonography, DopplerXenonHealth ServicesGene FlowBlood Circulation TimeUltrasonography, Doppler, Color