Microbial flora in the intestinal mucosae of patients
Total genomic DNA samples were extracted from mucosal samples with OMEGA Soil DNA Kit (OmegaBio-Tek, Norcross, GA, USA), following the manufacturers instructions. After that, the V3  V4 region of bacterial 16S rRNA genes was amplificated via polymerase chain reaction (PCR). PCR amplicons were purified with Vazyme VAHTSTM DNA Clean Beads (Vazyme , Nanjing, China) and quantified via the Quant-iT PicoGreen dsDNA Assay Kit (Invitrogen, Carlsbad, CA, USA), after which they were pooled and multiplexed at equal concentrations. Raw pair-end 2250 bp sequencing was performed through the Illlumina NovaSeq platform (Illumina, San Diego, California, USA) with NovaSeq 6000 SP Reagent Kit at Personal Biotechnology Co., Ltd (Shanghai, China).