Cerebral ArteriesMiddle Cerebral ArteryInfarction, Middle Cerebral ArteryArteriesCerebrovascular CirculationCerebral InfarctionPosterior Cerebral ArteryAnterior Cerebral ArteryTomography, X-Ray ComputedBrain IschemiaCerebral AngiographyBasilar ArteryBrainCerebral Arterial DiseasesPulmonary ArteryCarotid ArteriesIschemic Attack, TransientArterial Occlusive DiseasesCerebral PalsyCarotid Artery, InternalRenal ArteryColonography, Computed TomographicFemoral ArteryUltrasonography, Doppler, TranscranialMesenteric ArteriesIntracranial AneurysmVertebral ArteryBlood Flow VelocityInfarction, Anterior Cerebral ArteryIntracranial Embolism and ThrombosisCerebral HemorrhageSubarachnoid HemorrhageTemporal ArteriesCarotid Artery DiseasesCerebrovascular DisordersBrain EdemaTomographyCircle of WillisCerebral VeinsMagnetic Resonance AngiographyIliac ArteryMagnetic Resonance ImagingTime FactorsInfarction, Posterior Cerebral ArteryVasoconstrictionStrokeCoronary Artery BypassTomography, Emission-ComputedCerebral RevascularizationRadial ArteryDisease Models, AnimalReperfusionRats, Sprague-DawleyMalaria, CerebralSubclavian ArteryUmbilical ArteriesTomography, Emission-Computed, Single-PhotonNeuroprotective AgentsMammary ArteriesTreatment OutcomeAngiographyRegional Blood FlowBlood PressureImaging, Three-DimensionalCarotid Artery, CommonMuscle, Smooth, VascularAneurysm, RupturedTomography, OpticalVasodilationCoronary VesselsImage Processing, Computer-AssistedBrain InfarctionCarotid Artery, ExternalCarotid StenosisOphthalmic ArterySensitivity and SpecificityAngiography, Digital SubtractionHepatic ArteryCoronary AngiographyBrachial ArterySplenic ArteryVasospasm, IntracranialCeliac ArteryProspective StudiesRats, WistarPia MaterMesenteric Artery, SuperiorPredictive Value of TestsUltrasonography, DopplerDogsVasodilator AgentsCarotid Artery ThrombosisRetrospective StudiesFollow-Up StudiesConstrictionHemodynamicsEndothelium, VascularReproducibility of ResultsEmbolization, TherapeuticReperfusion Injury