老年人听到第三心音,常提示的是()
A.高血压
B.动脉粥样硬化
C.健康人
D.贫血
E.心功能不全
参考答案:E
Mr. Black ______ Shanghai in a few days. Do you know when the earliest plane ______
on Sunday? [ ]
A. is leaving, takes off
B. leaves, takes off
C. is leaving, is taking off
D. leaves, is taking off
以下牙体缺损修复的机械原则中,错误的是()
A.牙体预备体相对的轴壁越接 * * 行,固位力越大
B.预备体的龈距越大,越能更好的阻止修复体旋转移位
C.牙体预备体的横截面直径越小,修复体越易绕支点转动
D.通过限制就位道的几何形态,可改善固位力
E.瓷、树脂修复体,不宜设计洞缘斜面