Table 2.

Plasma TM concentration at different time in NEC group and PRE group (ng/ml), mean ± SD

Time points	NEC group	PRE group	t	P
Baseline	18.06 ± 3.24	17.06 ± 1.48	1.004	0.330
1 week	28.73 ± 3.02	24.80 ± 3.18	2.451	0.029
2 weeks	23.15 ± 5.65	17.59 ± 2.42	3.259	0.005
4 weeks	23.88 ± 8.51	15.41 ± 2.89	2.305	0.047
12 weeks	21.59 ± 7.49	16.17 ± 2.40	1.552	0.185

NEC group: Osteonecrosis group; PRE group: Prevention group; TM: Thrombomodulin; SD: Standard deviation.