Table 5.

Comparison of levels of EGF and amylase before radiotherapy, and after 21 d and 42 d of radiotherapy (x̅ ± sd)

Time	Group	Amylase (ng/mL)	EGF (ng/L)
Before radiotherapy	Control group (n=46)	211.36±46.84	69.63±10.35
	Test group (n=51)	213.94±44.76	70.16±9.68
	t	0.277	0.261
	P	0.782	0.795
After 21 d of radiotherapy	Control group (n=46)	273.95±36.98***	99.63±12.74***
	Test group (n=51)	328.74±40.09***	143.86±20.47***
	t	6.974	12.613
	P	<0.001	<0.001
After 42 d of radiotherapy	Control group (n=46)	342.74±51.29***,###	186.63±20.41***,###
	Test group (n=51)	417.96±58.62***,###	257.83±31.48***,###
	t	6.693	13.060
	P	<0.001	<0.001

Note: Paired t-test was used for the comparison in the same group before radiotherapy;

^***P<0.001.

Paired t-test was used for the comparison in the same group after 21 d of radiotherapy;

^###P<0.001.

EGF: epidermal growth factor.