十二指肠溃疡的好发部位是（）. ["球部","降部","水平部","升部","降部和升部"]
胆道蛔虫病腹痛的特点（）. ["阵发性腹部绞痛","持续性腹部胀痛","持续性绞痛伴阵发性加重","阵发性钻顶样绞痛","刀割样腹痛"]
胆总管引流术后，T管引流胆汁过多常提示（）. ["肝细胞分泌亢进","胆管分泌胆汁过多","胆囊浓缩功能减退","胆道下端梗阻","十二指肠反流"]
决定工厂用户供电质量的指标为（）。 ["A、电压","B、频率","C、可靠性","D、电流"]
测量误差＝测量值－（）。 ["A、统计值","B、平均值","C、测量结果","D、真值"]
循泵出口蝶阀油站的作用是（），并使出口门有逆止门的作用。
