甲氨蝶呤(MTX)属于周期特异性药物,为叶酸拮抗剂,抑制二氢叶酸还原酶,使其不能转变为四氢叶酸,从而干扰DNA合成,使肿瘤细胞不能增生,临床上主要用于白血病、绒癌和实体肿瘤等治疗。MTX在化疗应用时常为大剂量及长期给药,该药应用的剂量越大,临床疗效越显著,但不良反应发生率也更高,导致治疗进展受到限制[1]。其临床不良反应有骨髓 Methotrexate (MTX) is a cycle-specific drugs, folic acid antagonist, inhibition of dihydrofolate reductase, so that it can not be converted to tetrahydrofolate, thus interfering with DNA synthesis, so that tumor cells can not proliferate, the main clinical use of Leukemia, choriocarcinoma and solid tumors and other treatment. MTX is often used in large doses and long-term chemotherapy in the application of the dose of the drug, the clinical efficacy of the more significant, but the incidence of adverse reactions are also higher, resulting in the treatment of progress is limited [1]. The clinical adverse reactions are bone marrow