16S functional prediction of gut microbiota in healthy male and cervical SCI groups. A. The abundance of nucleotide (Wilcoxon rank-sum test, P = 0.027), lipid metabolism (Wilcoxon rank-sum test, P = 0.027) and translation (Wilcoxon rank-sum test, P = 0.019) had significant decreased in SCI group. B. The lipid metabolism in level 2 (Wilcoxon rank-sum test, P = 0.025) and fat acid metabolism in level 3 (Wilcoxon rank-sum test, P = 0.014) of KEGG metabolic pathway abundance had significant decreased in SCI group.