Homozygous a-thalassemia (--/--) has what clinical outcome?
a. Incompatible with life
b. Severe anemia
c. Mild anemia
d. No anemia
ANS: A
When all four a genes are missing, no a globin chains are synthesized. All normal hemoglobins (A, A2, and F) require a chains. In utero, the predominant hemoglobin will be Hb Barts (g4). This is a high oxygen affinity hemoglobin and thus is not effective in reversible oxygen transport. There will also be some Hb Portland (z2g2) and traces of Hb H (b4). Hb Portland is the primary hemoglobin up until the third trimester of fetal life, so the fetus generally survives until the third trimester.
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A type-A Rh-negative infant has spherocytes on his blood film and a weakly positive direct antiglobulin test. What antibody will most likely be found on the infant's red cells?
a. IgG anti-A antibody b. IgM anti-A antibody c. D antibody d. Kell antibody
The PID is used to direct the useful beam of radiation
Indicate whether the statement is true or false