GDNF and necrotizing enterocolitis: In infants with NEC, the median values of GFAP [2.40 (0.30–3.10) vs. 1.40 (0.20–6.50) P = 0.767], GDNF [2.99 (0.56–10.30) vs. 2.84 (1.05–14.11) P = 0.859], and FABP-2 [646.80 (179.20–1,571.00) vs. 621.70 (278.40–2,207.00) P = 0.953] in the second sample were higher than those in the first sample.