Including cyclophosphamide, all-trans retinoic acid inhibition of rat spinal cord and methotrexate compared with sodium valproate is relatively obvious, but the abortion rate is higher, lower teratogenicity. 2. 其中环磷酰胺、全反式维甲酸对大鼠脊髓抑制作用较丙戊酸钠及甲氨蝶呤相对较明显,但流产率较高,致畸率较低。