To explore the fecal bile acid profile of patients with radiation enteritis, to clarify the types of bile acids that are closely related to the occurrence of radiation enteritis; to explore the interaction between fecal bile acids and intestinal flora in patients with radiation enteritis, and to lay the foundation for further elucidation of the pathogenesis of radiation enteritis.

Inclusion Criteria:

1. . non-surgical cervical cancer patients aged 18 to 75 years who received radiotherapy;
2. . Patients who can fully understand the content of informed consent for this trial and voluntarily sign the written informed consent;
3. . able to receive follow-up examinations, follow-up examinations, and specimen retention on time;
4. . The case group met the diagnostic criteria for chronic radiation enteritis in the "Expert Consensus on the Diagnosis and Treatment of Radiation Proctitis in China (2018 edition)"; Control group 1: Non-surgical cervical cancer patients without chronic radiation enteritis after radiotherapy; Control group 2: Patients with cervical cancer who did not receive any treatment.

Exclusion Criteria;

1. . Presence of diseases affecting bile acid metabolism, such as hepatitis and cirrhosis of the liver from various causes, gallstones, etc;
2. . Patients who have previously undergone cholecystectomy or partial resection of the intestine;
3. . Taking drugs affecting bile acid metabolism due to other diseases, such as cholestyramine, anti-inflammatory and Xiaoyan lidan tablets, Danshu capsules, ursodeoxycholic acid, obeticholic acid, and proprietary Chinese medicines such as schisandrin B, Tanshinone IIA, and Yinjiazhuang;
4. . Recent use of drugs that affect gastrointestinal motility;
5. . Patients with moderate or severe renal impairment (blood creatinine > 2 mg/dL or 177 mmol/L), or abnormal liver function (ALT > 2 times the upper limit of normal value); moderate or severe chronic obstructive pulmonary disease; patients with severe hypertension, patients with cerebrovascular accidents; patients with congestive heart failure, unstable angina pectoris;
6. . Patients with mental or legal disabilities;
7. . Suspected or confirmed history of alcohol/substance abuse or other pathology that, in the judgment of the investigator, reduces the likelihood of enrollment or complicates enrollment;
8. . Refuse to sign informed consent;

patients are from Xijing Hospital.