Polycythemia VeraThrombocythemia, EssentialPolycythemiaJanus Kinase 2ThrombocytosisPrimary MyelofibrosisHydroxyureaMyeloproliferative DisordersBusulfanReceptors, ThrombopoietinPipobromanErythroid Precursor CellsThrombosisPlatelet CountMegakaryocytesAloeGranulocytesErythropoietinThrombopoietinPhlebotomyMutation, MissenseCarbazilquinoneMutationErythropoiesisAmino Acid SubstitutionLeukocytosisLeukemia, Myeloid, Chronic, Atypical, BCR-ABL NegativeBone MarrowSplenomegalyGPI-Linked ProteinsReceptors, ErythropoietinIsoantigensHomozygoteBloodlettingHematocritBlood PlateletsHematopoietic Stem CellsAntisickling AgentsLeukemia, Myelogenous, Chronic, BCR-ABL PositiveErythroid CellsHematopoiesis, ExtramedullaryPoint MutationThrombocytopeniaInterferon-alphaPlatelet Aggregation InhibitorsColony-Forming Units AssayReceptors, CytokineHematopoiesisThrombopoiesisDNA Mutational AnalysisHeterozygoteErythrocyte InclusionsProto-Oncogene ProteinsLeukemia, MyeloidBudd-Chiari SyndromeAnemia, Refractory