RecruitingClinical trialEstablishment of Precise Histological Evaluation Criteria for NASH Fibrosis ReversalCollect confirmed cases of NAFLD patients and enroll them in the study. Select patients with NASH and fibrosis stage F2-4 confirmed by liver biopsy, and collect clinical and pathological data for relevant evaluation and definition. Establish a NASH "fibrosis reversal" pathological evaluation system, based on a new reversal standard, establish non-invasive alternative indicators, and observe indicators.