we infused cortisol ( 450 micrograms/h for 48 h ) , thyrotropin-releasing hormone ( trh ) ( 25 micrograms/h for 48 h ) , and ritodrine ( 1.3 micrograms/kg/min for 24 h ) independently , and in double ( cortisol plus beta-agonist , cortisol plus trh ) , and in triple ( cortisol plus trh plus beta-agonist ) combinations into chronically catheterized fetal lambs between 0.88 and 0.90 gestation .
C0035661
ritodrine
C0032961
gestation