Conditions for joining China Bone Marrow Bank: 1, China citizen age 18-45 years old. 2. Good health, no blood-borne infectious diseases such as hepatitis B, hepatitis C and AIDS. 3. Permanent residence at the place of donation. (Volunteers can contact the local Red Cross to register in different places. 4. Relatives and spouses have no objection. (To avoid that donors can't donate smoothly after successful matching. ) 2. Registration method is 1. Telephone registration: broadcast donation hotlines in various places and report your name, address and date of birth. By phone. 2. Mailing materials: After telephone registration, the local donation office will mail you a copy of how to donate hematopoietic stem cells and how to donate them according to the address you reported. 3. Donate at the notified place: the bone marrow bank will arrange for you to have a blood test (5 ml) at an appropriate time, and store the HLA (human leukocyte antigen) after the test in the computer database for patients to find a match.