infants in whom rlf developed were gestationally younger ( p = 0.005 ) , required a longer period of mechanical ventilation ( p = 0.035 ) , had a greater exposure to oxygen ( p = 0.03 ) , and had a greater number of arterial po2 values between 75 and 99 mm hg ( p = 0.004 ) .
C0035344
rlf
C0030054
oxygen