Ultrasonography, DopplerUltrasonographyUltrasonography, Doppler, ColorUltrasonography, Doppler, PulsedDoppler EffectUltrasonography, Doppler, TranscranialBlood Flow VelocityUltrasonography, PrenatalEchocardiography, Doppler, PulsedEchocardiography, Doppler, ColorUltrasonography, Doppler, DuplexSensitivity and SpecificityReproducibility of ResultsEndosonographyProspective StudiesLaser-Doppler FlowmetryPulsatile FlowUltrasonography, InterventionalContrast MediaPredictive Value of TestsPregnancyNoninvasive VentilationRegional Blood FlowUltrasonography, MammaryTomography, X-Ray ComputedUmbilical ArteriesImaging, Three-DimensionalMagnetic Resonance ImagingObserver VariationSulfur HexafluorideFetal DiseasesDiastoleUltrasonicsCerebrovascular CirculationDiagnostic ImagingGestational AgeEchoencephalographyImage EnhancementRetrospective StudiesEchocardiographyCarotid Artery DiseasesPlacental CirculationAngiographyVascular ResistanceHemodynamicsTime FactorsMiddle Cerebral ArteryCarotid ArteriesArteriesFeasibility StudiesUterusSystoleMitral ValveReference ValuesTransducersTreatment OutcomeBlood PressureFetal Growth RetardationCoronary CirculationFollow-Up StudiesScrotumFetal HeartVentricular Function, LeftOphthalmic ArteryROC CurveImage Interpretation, Computer-AssistedPregnancy Trimester, SecondImage Processing, Computer-AssistedInfant, NewbornCerebral ArteriesMonitoring, PhysiologicUrographyCarotid StenosisPrenatal DiagnosisPreoperative CareOvarian CystsArterial Occlusive DiseasesRheologyCystsFetusSeverity of Illness IndexRespiratory InsufficiencyMagnetic Resonance AngiographyAbdomenPortal VeinVaginaCardiac CatheterizationTesticular DiseasesPregnancy Trimester, FirstPregnancy Trimester, ThirdPalpationAngiography, Digital SubtractionVentricular Dysfunction, LeftAuscultationElasticity Imaging TechniquesMetacarpophalangeal JointPositive-Pressure RespirationRisk FactorsStroke VolumeMicrocirculation