treat 治疗,含义最广,包括对伤口、病人进行诊断,制定治疗方案、开药方等.
eg.Cancer is difficult to treat.
cure 治愈；治疗,多指病后恢复健康
eg.The madicine cured her toothache.
heal （伤口或断骨）愈合；复原,多指创伤,外伤,也可指矛盾,分歧
eg.The wound heals rapidly.
还有一个意思相近的词
remedy 医治；补救,指消除身心上的不正常、不理想的状况
eg.Aspirin may remedy a headache.