VaricoceleTestisUltrasonography, DopplerRegional Blood FlowUltrasonography, Doppler, ColorTestosteroneSpermatogenesisUltrasonographyBlood Flow VelocityUltrasonography, Doppler, PulsedUltrasonography, Doppler, TranscranialDoppler EffectUltrasonography, PrenatalPulsatile FlowCerebrovascular CirculationSensitivity and SpecificityEchocardiography, Doppler, PulsedUltrasonography, Doppler, DuplexEchocardiography, Doppler, ColorProspective StudiesUmbilical ArteriesLaser-Doppler FlowmetryReproducibility of ResultsVascular ResistancePregnancyPlacental CirculationEchoencephalographyCerebral ArteriesContrast MediaMiddle Cerebral ArteryArteriesPredictive Value of TestsPortal VeinScrotumUltrasonography, InterventionalFetal DiseasesHemodynamicsBlood PressureTomography, X-Ray ComputedOphthalmic ArteryEndosonographyUterusTesticular DiseasesHepatic VeinsLiver CirculationMagnetic Resonance ImagingArterial Occlusive DiseasesGestational AgeImaging, Three-DimensionalTime FactorsReference ValuesObserver VariationPortographyCarotid Artery DiseasesFetal Growth RetardationAngiographyUltrasonography, MammaryUltrasonicsIntracranial Embolism and ThrombosisHepatic ArteryRetrospective StudiesMicrocirculationRenal ArteryOvarian CystsCarotid ArteriesTreatment OutcomeSpermatic CordCerebrovascular DisordersIntracranial PressureMetacarpophalangeal JointFollow-Up StudiesFetal HeartValsalva ManeuverMesenteric Artery, SuperiorInfant, NewbornPregnancy Trimester, SecondConstriction, PathologicSubclavian Steal SyndromeDogsCollateral CirculationVertebral ArteryLegSulfur HexafluorideFetusDiastoleSeverity of Illness IndexCarotid StenosisVeinsROC CurveRheologyAbdomenVaginaMagnetic Resonance AngiographySynovitisFemoral ArteryPregnancy Trimester, FirstHypertension, PortalCarbon DioxideRenal CirculationCarotid Artery, Internal