small interfering RNA priority journal 76 human 72 nonhuman 72 Animals 68 controlled study 68 article 66 Humans 58 metabolism 56 unclassified drug 54 RNA, Small Interfering 48 human cell 48 animal cell 46 animal 42 mouse 36 Mice 34 genetics 32 messenger RNA 32 protein expression 30 Cell Line 28 gene silencing 28 Article 26 cell line 26 gene expression 26 physiology 26 upregulation 24 female 22 gene expression regulation 22 protein function 22 protein protein interaction 22