Study on Glucocorticoid Combined With Gamma Globulin and Ropristine N01 in Treatment of Initial Severe ITP

The goal of this clinical trial is to learn if romiplostim N01 works to treat severe primary immune thrombocytopenia in adults. It will also learn about the safety of romiplostim N01. The main question it aims to answer is: TO evaluate the effectiveness of the combination treatment of glucocorticoids, gamma globulin and romiplostim N01 in patients with severe primary immune thrombocytopenia during the initial treatment period for one month. Participants will: Romiplostim N01, starting dose of 1 µg/kg, subcutaneous injection, given on the third day of IVIG, once a week, for up to one month. IVIG, 400mg/kg/d, intravenous administration, continuous administration for 3-5 days. Prednisone, 0.8mg/kg/d, taken orally or intravenously, for up to one month.