[名词解释] 预防接种(prophylacticvaccination)

亚单位疫苗(subunitvaccine) 疫苗(vaccine) 少枝胶质细胞瘤的常见CT表现为() ["A．斑块状钙化","B．混合密度","C．不规则增强","D．可呈低密度","E．以上都是"] 主动免疫(activeimmunity) 计划免疫(plannedimmunization) 预防接种(prophylacticvaccination)