Blood PressureHeart RateBlood VesselsArteriesPressureBlood Pressure DeterminationBlood Flow VelocityHypertensionBlood Pressure Monitoring, AmbulatoryRegional Blood FlowCerebral ArteriesFemoral ArteryPulmonary ArteryCarotid ArteriesMiddle Cerebral ArteryHemodynamicsMesenteric ArteriesOphthalmic ArteryPulsatile FlowVascular ResistanceMesenteric Artery, SuperiorAntihypertensive AgentsCerebrovascular CirculationRenal ArteryCoronary VesselsUmbilical ArteriesRadial ArteryBrachial ArteryUltrasonography, DopplerTime FactorsHydrostatic PressureVasodilationBronchial ArteriesUltrasonography, Doppler, PulsedBasilar ArteryVasoconstrictionUterusUltrasonography, Doppler, TranscranialCarotid Artery, InternalSystoleUltrasonography, Doppler, ColorEndothelium, VascularBlood Pressure MonitorsDogsArterial PressureVasodilator AgentsIliac ArteryRetinal VesselsCardiac OutputProspective StudiesCarotid Artery, CommonLymphatic VesselsPregnancyVertebral ArteryCoronary Artery BypassSympathetic Nervous SystemUterine ArteryMammary ArteriesVasoconstrictor AgentsRats, Inbred SHRCoronary CirculationMuscle, Smooth, VascularReference ValuesTreatment OutcomeCarotid Artery DiseasesNorepinephrineDiastoleLaser-Doppler FlowmetryFollow-Up StudiesRats, Sprague-DawleyAnalysis of VarianceHypotensionSubclavian ArteryPulseOxygenAortaFetal Growth RetardationUltrasonographySplanchnic CirculationReninRisk FactorsIntracranial PressureHypotension, OrthostaticCarotid Artery, ExternalIntraocular PressureRetinal ArteryNitric OxideNeovascularization, PhysiologicKidneyTransducers, PressureRats, Inbred WKYNitroglycerinRenal Artery ObstructionCircle of WillisDisease Models, AnimalSplenic ArteryDose-Response Relationship, DrugCardiovascular SystemCarbon DioxideGestational Age