n. an increase in the proportion of immature red blood cells (reticulocytes) in the bloodstream. It is a sign of increased output of new red cells from the bone marrow.
n. an immature red blood cell (erythrocyte). Reticulocytes may be detected and counted by staining living red cells with certain basic dyes that result in the formation of a blue precipitate (reticulum) within the reticulocytes. They normally comprise about 1% of the total red cells and are increased (reticulocytosis) whenever the rate of red cell production increases.... reticulocyte
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