{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,2]],"date-time":"2026-05-02T21:04:00Z","timestamp":1777755840255,"version":"3.51.4"},"reference-count":0,"publisher":"S. Karger AG","license":[{"start":{"date-parts":[[2009,2,24]],"date-time":"2009-02-24T00:00:00Z","timestamp":1235433600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/karger.com\/pages\/terms-and-conditions"},{"start":{"date-parts":[[2009,2,24]],"date-time":"2009-02-24T00:00:00Z","timestamp":1235433600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/karger.com\/pages\/terms-and-conditions"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Acta Haematol"],"abstract":"<jats:p>Megakaryocytopoiesis in polycythemia vera (PV) was characterized by in vitro growth of marrow megakaryocytic progenitors (CFU-Meg) and quantitation of megakaryocyte numbers in marrow biopsy specimens in 14 patients with PV. Megakaryocyte numbers and CFU-Meg numbers in the 14 patients were variable, with values from the control range to markedly increased numbers. Nine of the 14 patients showed spontaneous CFU-Meg growth, and the presence or absence of spontaneous CFU-Meg growth was found to be related to the degree of marrow megakaryocyte increase, i.e., those with spontaneous CFU-Meg had higher megakaryocyte numbers. None of the plasmas from the PV patients contained detectable levels of megakaryocyte colony-stimulating activity (Meg-CSA), assayed using the culture with nonadherent normal marrow cells and tested plasma without phytohemagglutinin-stimulated leukocyte-conditioned medium as an exogenous source of Meg-CSA. Increased megakaryocyte numbers and resultant thrombocytosis in PV are likely based on the abnormal population of CFU-Meg.<\/jats:p>","DOI":"10.1159\/000205681","type":"journal-article","created":{"date-parts":[[2009,2,24]],"date-time":"2009-02-24T13:05:14Z","timestamp":1235480714000},"page":"1-6","source":"Crossref","is-referenced-by-count":10,"title":["Megakaryocytopoiesis in Polycythemia vera: Characterization by Megakaryocytic Progenitors (CFU-Meg) in vitro and Quantitation of Marrow Megakaryocytes"],"prefix":"10.1159","author":[{"given":"Hideo","family":"Kimura","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tohru","family":"Ohkoshi","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shin","family":"Matsuda","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tatsumi","family":"Uchida","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shigeo","family":"Kariyone","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"127","published-online":{"date-parts":[[2009,2,24]]},"container-title":["Acta Haematologica"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.karger.com\/Article\/Pdf\/205681","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/karger.com\/article-pdf\/doi\/10.1159\/000205681","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T12:16:27Z","timestamp":1777464987000},"score":1,"resource":{"primary":{"URL":"https:\/\/karger.com\/article\/doi\/10.1159\/000205681"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2009,2,24]]},"references-count":0,"URL":"https:\/\/doi.org\/10.1159\/000205681","archive":["Portico"],"relation":{},"ISSN":["0001-5792","1421-9662"],"issn-type":[{"value":"0001-5792","type":"print"},{"value":"1421-9662","type":"electronic"}],"subject":[],"published":{"date-parts":[[2009,2,24]]}}}