A 27-year-old patient complains of nasal hemorrhages, multiple bruises on the anterior surface of the trunk and extremities, sudden weakness. In blood: Hb- 74 g/l, reticulocytes - 16%, RBCs -2,5 × 1012/l, platelets - 30 × 109/l, ESR - 25 mm/h. What is the most effective measure for the treatment of thrombocytopenia?