Figure 2. Venn diagram and microbial community structure assessment in the two groups. Number of common and specific OTUs for grouped samples with OTUs=0.03 (A). Comparison of common and specific microbiota at phylum level (B). Community richness assessment contains the ACE estimator (C) and the Chao estimator (D); community diversity assessment contains the Shannon index (E) and the Simpson index (F). Principal coordinate analysis of 16S rRNA sequences from all samples using unweight (G) and weight (H). Results were compared by unpaired t test with Welch’s correction, *P < 0.05.