Key Points. 1  Megaloblasts are large nucleated RBC precursors with noncondensed chromatin. 2  The most common causes of megaloblastic, macrocytic anemia are deficiency or defective utilization of vitamin B12 or folate. 3  Do CBC, RBC indices, reticulocyte count, and peripheral smear.
Wiktionary (0.00 / 0 votes) Rate this definition: vein (Noun). A blood vessel that transports blood from the capillaries back to the heart. vein (Noun). (used in plural veins) The entrails of a shrimp. vein (Noun). In leaves, a thickened portion of the leaf containing the vascular bundle. vein (Noun).
Vein, Vain, and Vane The words vein, vain, and vane sound identical, but their meanings are very different. Vein The noun vein has several meanings: A blood vessel that carries blood from the capillaries towards the heart. varicose veins A distinctive style or manner. Mr Mellor continued in the same vein despite several reprimands.