Mesenteric VeinsMesenteric Vascular OcclusionPortal VeinMesenteric ArteriesMesenteric Artery, SuperiorSplenic VeinPortal SystemPancreaticoduodenectomySplanchnic CirculationIliac VeinLigationMesenteric Artery, InferiorVeinsHypertension, PortalVenous ThrombosisHepatic VeinsArteriesTomography, X-Ray ComputedVena Cava, InferiorThrombosisGastrointestinal HemorrhagePancreatic NeoplasmsTreatment OutcomeRenal VeinsFemoral VeinTooth AbnormalitiesSaphenous VeinCeliac ArterySuperior Mesenteric Artery SyndromeVasoconstrictionNorepinephrinePulmonary ArteryRenal ArteryVisceraVaricose VeinsFemoral ArteryCarotid ArteriesCerebral ArteriesVasodilationVena Cava, SuperiorSuperior ColliculiDogsPulmonary VeinsBasilar ArteryTime FactorsMuscle ContractionVasoconstrictor AgentsBiological FactorsLiver CirculationVasodilator AgentsJugular VeinsIofetamineSplenic Artery