- Surfactant protein expression is increased in the ipsilateral but not contralateral lungs of fetal sheep with left-sided diaphragmatic hernia. Davey, M.G., Biard, J.M., Robinson, L., Tsai, J., Schwarz, U., Danzer, E., Adzick, N.S., Flake, A.W., Hedrick, H.L. Pediatr. Pulmonol. (2005)