<qa>  What is the randomized, double-blind, placebo-controlled parallel group study?This is a randomized, double-blind, placebo-controlled parallel group study on the efficacy, safety of intramuscular injections of autologous immunoglobulin in patients with moderate-to-severe atopic dermatitis. After providing informed consent, patients will be assessed for study eligibility at the baseline visit. Patients will undergo screening within 28 days prior to randomization as wash out period, and during the screening period, treatment with medications including systemic corticosteroids and systemic immunomodulating agents for atopic dermatitis will be wash-out for at least 28 days prior to baseline exclude moisturizers. 