Effect of Stem Cell Infusion Time on aGVHD in Patients With Hematological Malignancies

Inclusion Criteria: * Definite diagnosis of malignant hematologic disease before transplantation, age 12-60 years old, gender is not limited, race is not limited; * Patients who are proposed to receive allo-PBSCT for the first time; * Eastern Cooperative Oncology Group (ECOG) score 0-2; * No serious organ failure and active infection; * Voluntary open randomized controlled study to observe whether the time of stem cell infusion affects the occurrence of aGVHD after transplantation; * Each subject must sign an informed consent form (ICF) indicating that he/she understands the purpose and procedures of the study and is willing to participate in the study; in view of the patient's condition, if the patient's own signature is not conducive to the treatment of his/her condition, the ICF will be signed by the legal representative. Exclusion Criteria: * Those with severe organ dysfunction or disease, such as severe disease and dysfunction of the heart, liver, kidneys and pancreas; * Pregnant patients; * Patients and/or authorized family members who refuse to undergo an open randomized controlled study to observe whether the time of stem cell infusion affects the occurrence of aGVHD after transplantation; * Any life-threatening disease, physical condition, or organ system dysfunction that, in the opinion of the investigator, may compromise patient safety and put the results of the study at unnecessary risk; drug-dependent individuals; patients with uncontrolled psychiatric disorders; and individuals with cognitive dysfunction; * Participants in other clinical studies that may affect aGVHD within 3 months; * Those whom the investigator considers unsuitable for enrollment (e.g., those who anticipate that patients will not be able to adhere to the examination and treatment due to financial and other issues).