Venous ThrombosisPortal VeinThrombosisHypertension, PortalHypertensionVeinsThrombophlebitisFemoral VeinPortal SystemHypertension, PulmonaryIliac VeinUpper Extremity Deep Vein ThrombosisPhlebographyMesenteric VeinsSplenic VeinRenal VeinsPulmonary EmbolismAnticoagulantsVaricose VeinsJugular VeinsSaphenous VeinPopliteal VeinSubclavian VeinSinus Thrombosis, IntracranialIntracranial ThrombosisCoronary ThrombosisPortal PressureVena Cava, InferiorHypertension, RenalFibrin Fibrinogen Degradation ProductsRisk FactorsHeparin, Low-Molecular-WeightBlood PressureTreatment OutcomeAxillary VeinThrombophiliaBudd-Chiari SyndromeHepatic VeinsPostthrombotic SyndromeCerebral VeinsPortasystemic Shunt, SurgicalCarotid Artery ThrombosisRetrospective StudiesAntihypertensive AgentsUltrasonography, Doppler, DuplexHypertension, RenovascularPulmonary VeinsTime FactorsEsophageal and Gastric VaricesVenous ThromboembolismProspective StudiesHeparinFollow-Up StudiesFactor VLiver CirculationProtein S DeficiencyThromboembolismLegThrombectomyHypertension, MalignantVena Cava FiltersTomography, X-Ray ComputedFibrinolytic AgentsWarfarinMesenteric Vascular OcclusionLiver CirrhosisPregnancy Complications, CardiovascularPlethysmography, ImpedancePostphlebitic SyndromePostoperative ComplicationsStockings, CompressionIncidenceHemorrhageIntermittent Pneumatic Compression DevicesSplenorenal Shunt, SurgicalRecurrenceGastrointestinal HemorrhageLiver TransplantationUltrasonography, DopplerSplenectomyPortacaval Shunt, SurgicalUmbilical VeinsHepatic ArteryActivated Protein C ResistanceThrombolytic TherapyUltrasonography, Doppler, ColorBandagesRisk AssessmentVenous InsufficiencyProthrombinAngiographySagittal Sinus ThrombosisDisease Models, AnimalHypersplenismPrevalenceLower ExtremityIntracranial Embolism and ThrombosisLigationHypertension, Pregnancy-InducedCatheterization, Central Venous