highly significantP<0.01
A highly significant difference was seen between sub-groups 1a, 2a (P<0.01) and sub-groups 1b, 2b (P<0.01), as shown in Table 2 .
A highly significant difference was seen between sub-groups 1a, 2a (P<0.01) and sub-groups 1b, 2b (P<0.01), as shown in Table 2 .