慢性肺源性心脏病的X线诊断标准有()、()、()。
参考答案:右下肺动脉干扩张,其横径≥15mm;横径与气管横径之比≥1.07;肺动脉段明显突出或其高度≥3mm,右心室肥大
What does the speak mean a. World War One did not break out over night though it seemed so. b. World War One Came into being in a short period of time. c. World War One had been fought for years. d. World War One did not last for a long time.
井塌的原因,钻井液密度过()井内液柱压力不足平衡地层压力,致使倾角过大或胶结不好的地层垮塌。
A、大
B、小
C、多
D、少