“The apparent Km of estrogen synthetase for 1,4-androstadiene-3,17-dione was 1.3μM, and the apparent Km of … of placental microsomal 17β-hydroxysteroid oxidoreductase for NADH was 0.5 mM and that for NADPH was 0.67 mM. Androstenedione … [3H]-1,4-androstadiene-3,17-dione …).”