Primary MyelofibrosisReticulinBone MarrowSplenomegalyMegakaryocytesJanus Kinase 2Osteitis Fibrosa CysticaBone Marrow CellsBone Marrow TransplantationMyeloproliferative DisordersBone and BonesReceptors, ThrombopoietinFibrosisCystic FibrosisMyelodysplastic SyndromesBone RemodelingBone Marrow DiseasesBone Marrow ExaminationBone Marrow NeoplasmsHematopoietic Stem CellsBone DensityBone ResorptionBone Marrow PurgingMice, Inbred C57BLHematopoiesisBone Neoplasms