microbiome 74 human 68 nonhuman 65 Microbiome 54 intestine flora 48 Article 46 Humans 46 Gastrointestinal Microbiome 34 Microbiota 33 microflora 33 controlled study 31 RNA 16S 29 metagenomics 27 microbial community 27 genetics 26 article 24 Animals 22 animal 22 female 22 microbiology 21 metabolism 20 male 19 Metagenomics 18 bacterium 17 mouse 17 Bacteria 16 microbial diversity 16 Female 14 RNA, Ribosomal, 16S 12 adult 12