患儿,女,4岁。从小体弱、易累、易患感冒,发育相对滞后。查体胸骨左缘第2肋间可闻及粗糙连续性机器样杂音,可见毛细血管搏动及股动脉枪击音。考虑为() ["法洛三联症","主动脉瓣狭窄","房间隔缺损","动脉导管未闭","大动脉转位"]
有一水泥试样,用雷氏法测定其安定性,测试数据如表所示。经计算判断该水泥试样的安定性是()o ["不合格","合格","应立即童做","应立即用试饼法重做,并以试饼法结果为准"]
镗刀头的截面形状有()等几种形式。 ["方形","长方形","菱形","圆形","椭圆形","锥形"]
ZPW-2000A衰耗盘的测试孔有哪些?
风景如画主义
顺序抽样法