inclusion criteria: 1. 18-70 years old (including 18 and 70 years old), regardless of gender; 2. infection with new coronavirus pneumonia was confirmed by throat swab nucleic acid test. patients with severe and critical illness were clinically judged. the symptoms of acute infection have been alleviated after treatment (at least 14 days after onset, no fever for more than 3 days), and the disease is recovering within three months; 3. ct examination of patients with multiple fibrotic shadows in both lungs; 4. blood routine, liver, and kidney functions are within the controllable range: such as the normal upper limit of plasma total bilirubin and creatinine ≤ 1.5 times; ast, alt, ldh ≤ 2 times the normal upper limit; sufficient hematopoietic function: such as white blood cells ≥4.0 × 109 / l, platelets ≥100 × 109 / l; 5. signed informed consent.

inclusion criteria: 1. 18-70 years old (including 18 and 70 years old), regardless of gender; 2. infection with new coronavirus pneumonia was confirmed by throat swab nucleic acid test. patients with severe and critical illness were clinically judged. the symptoms of acute infection have been alleviated after treatment (at least 14 days after onset, no fever for more than 3 days), and the disease is recovering within three months; 3. ct examination of patients with multiple fibrotic shadows in both lungs; 4. blood routine, liver, and kidney functions are within the controllable range: such as the normal upper limit of plasma total bilirubin and creatinine ≤ 1.5 times; ast, alt, ldh ≤ 2 times the normal upper limit; sufficient hematopoietic function: such as white blood cells ≥4.0 × 109 / l, platelets ≥100 × 109 / l; 5. signed informed consent.

inclusion criteria: 18-70 years old (including 18 and 70 years old), regardless of gender; infection with new coronavirus pneumonia was confirmed by throat swab nucleic acid test. patients with severe and critical illness were clinically judged. the symptoms of acute infection have been alleviated after treatment (at least 14 days after onset, no fever for more than 3 days), and the disease is recovering within three months; ct examination of patients with multiple fibrotic shadows in both lungs; blood routine, liver, and kidney functions are within the controllable range: such as the normal upper limit of plasma total bilirubin and creatinine ≤ 1.5 times; ast, alt, ldh ≤ 2 times the normal upper limit; sufficient hematopoietic function: such as white blood cells ≥4.0 × 109 / l, platelets ≥100 × 109 / l; signed informed consent.

inclusion criteria: 18-70 years old (including 18 and 70 years old), regardless of gender; infection with new coronavirus pneumonia was confirmed by throat swab nucleic acid test. patients with severe and critical illness were clinically judged. the symptoms of acute infection have been alleviated after treatment (at least 14 days after onset, no fever for more than 3 days), and the disease is recovering within three months; ct examination of patients with multiple fibrotic shadows in both lungs; blood routine, liver, and kidney functions are within the controllable range: such as the normal upper limit of plasma total bilirubin and creatinine ≤ 1.5 times; ast, alt, ldh ≤ 2 times the normal upper limit; sufficient hematopoietic function: such as white blood cells ≥4.0 × 109 / l, platelets ≥100 × 109 / l; signed informed consent.

inclusion criteria: 1. 18-70 years old (including 18 and 70 years old), regardless of gender; 2. infection with new coronavirus pneumonia was confirmed by throat swab nucleic acid test. patients with severe and critical illness were clinically judged. the symptoms of acute infection have been alleviated after treatment (at least 14 days after onset, no fever for more than 3 days), and the disease is recovering within three months; 3. ct examination of patients with multiple fibrotic shadows in both lungs; 4. blood routine, liver, and kidney functions are within the controllable range: such as the normal upper limit of plasma total bilirubin and creatinine ≤ 1.5 times; ast, alt, ldh ≤ 2 times the normal upper limit; sufficient hematopoietic function: such as white blood cells ≥4.0 × 109 / l, platelets ≥100 × 109 / l; 5. signed informed consent.

inclusion criteria: 1. 18-70 years old (including 18 and 70 years old), regardless of gender; 2. infection with new coronavirus pneumonia was confirmed by throat swab nucleic acid test. patients with severe and critical illness were clinically judged. the symptoms of acute infection have been alleviated after treatment (at least 14 days after onset, no fever for more than 3 days), and the disease is recovering within three months; 3. ct examination of patients with multiple fibrotic shadows in both lungs; 4. blood routine, liver, and kidney functions are within the controllable range: such as the normal upper limit of plasma total bilirubin and creatinine ≤ 1.5 times; ast, alt, ldh ≤ 2 times the normal upper limit; sufficient hematopoietic function: such as white blood cells ≥4.0 × 109 / l, platelets ≥100 × 109 / l; 5. signed informed consent.