中文摘要：

微小RNA（miRNA）是一类长度为21~25个核苷酸的内源性非编码RNA,能够通过与靶基因3′非翻译区结合在转录后水平负调控基因的表达。miRNA与人类疾病的发生发展密切相关,且血液、尿液中的miRNA稳定性强、重复性好,因此可作为多种疾病尤其是肿瘤诊断的非创伤性生物标志物。近年来,通过研究发现,在肝、脑损伤,急性心肌梗死及肿瘤等疾病中,有着相对特异的miR-NA出现在血液或尿液中。

英文摘要：

MicroRNAs（miRNAs）are endogenous non-coding RNAs,about 22 nucleotides in length,which mediate negative regulation of gene expression at a post-transcriptional level by binding to complementary sequences in the 3′-untranslated regions of target mRNAs.MiRNAs are involved in the pathogenesis and progression of human diseases;and miRNAs in blood and urine are stable and reproducible.Therefore,miRNAs might serve as non-invasive biomarkers for diagnostic of various diseases,especially cancers.In the past few years,some relatively specific miRNAs were found in blood and urine as diagnostic markers of liver or brain injury,acute myocardial infarction and tumer.