6Myer EC, Morris DL, Brase DA, et al. Naltrexone therapy of apnea in children with elevated cerebropsinal fluid beta-endorphin [J ].Ann Neurol, 1990, 27(1): 75-80.
7MacDonald MG, Herman BH, Kammerman LA, et al. Cerebrospinal fluid and plasma beta-endorphin-like immunoreactivity in full-term neonates and in preterm neonates with and without apnea of prematurity[J]. Dev Pharmacol Ther, 1990, 15(1):8-15.
8Storm H, Stoltenberg L, Saugstad OD, et al. Beta-endorphin immunoreactivity levels in CSF after laryngeal chemoreflex activation correlate with apnea duration in piglets[J] .J Perinat Med, 1996, 24(4) :363-72.
9Mehta Rajeev, Weiberger Barry, Usmani Shaista S, et al. Theophylline alters neurophil function in preterm infants [ J ]. Biol Neonate, 2002, 81(3): 176-81.