风湿性心脏病二尖瓣关闭不全的彩色血流显示,正确的是
A.全部为蓝色
B.全部为红色
C.血流信号常呈五彩镶嵌色
D.A、B、C均可出现
E.以上都不是
参考答案:C
Mr Smith was having a meeting at that time, otherwise he ______________over to help us.
A.would have come
B.would come
C.had come
D.was going to come
人参皂苷二醇型的苷元类型是()
A.齐墩果酸型
B.乌索酸型
C.羽扇豆烷型
D.羊毛甾烷型
E.达玛烷型