LVEDV是反映左心前负荷的最佳指标。
参考答案:对
有一个八位二进制数的补码是11111101,其相应的十进制数是 ( )
A.509
B.-2
C.-3
D.253
I’ll call you _____ I get there. [ ]
A. as soon as
B. while
C. how long
D. how soon