the fall in specific activity of phosphatidylcholine with time was measured after the intratracheal administration of either a trace dose of 3h-labeled natural surfactant and synthetic 14c-dipalmitoylphosphatidylcholine ( dppc ) at birth or a treatment dose of the same mixture at 5 h of age ( about 55 mg of total surfactant lipid/kg body weight ) .
C1959616
phosphatidylcholine
C0000039
dipalmitoylphosphatidylcholine