释义 |
DictionarySeetarget cellMexican Hat Cell
tar·get cell1. an erythrocyte with a dark center surrounded by a light band that again is encircled by a darker ring; it thus resembles a shooting target; such cells appear in target-cell anemias or after splenectomy; Synonym(s): Mexican hat cell2. a cell lysed by cytotoxic T lymphocytes, as in graft rejection. A thin red blood cell with the appearance of a target with a bull’s eye due to a disproportional increase in the surface membrane-to-volume ratio secondary to increased membrane surface area or decreased haemoglobin Aetiology • Liver disease Lecithin cholesterol acyltransferase activity may decrease in obstructive liver disease, increasing the cholesterol:phospholipid ratio, thereby increasing red cell surface area • Iron deficiency Decreased haemoglobin content relative to surface area—seen in thalassemias, haemoglobin C disease, etc. • Post-splenectomy Altered erythrocytes are not removed from the circulation • Autosplenectomy Sickle cell anaemiatar·get cell (tahr'gĕt sel) 1. An erythrocyte in target cell anemia, with a dark center surrounded by a light band that again is encircled by a darker ring, thus resembling a target used in practice with firearms or archery; such cells also appear after splenectomy. 2. A cell lysed by cytotoxic T lymphocytes, as in graft rejection. Synonym(s): codocyte, leptocyte, Mexican hat cell. tar·get cell (tahr'gĕt sel) An erythrocyte in target cell anemia, with a dark center surrounded by a light band that again is encircled by a darker ring, thus resembling a target used in practice with firearms or archery; such cells also appear after splenectomy. Synonym(s): leptocyte, Mexican hat cell. LegalSeeCellFinancialSeecell |