严重吸气性呼吸困难最主要特点是（）
A.端坐呼吸
B.明显发绀
C.三凹征
D.鼻翼扇动
E.呼吸节律、频率、深度改变
参考答案：C
The story is ___________ that one.
A．as more interesting as
B．so more interesting as
C．as interesting as
D．so much interesting as
在SDH测试中，如测试VC-4通道，则选择TSS5信号结构；测试140Mbit/s通道，则选择TSS1信号结构。
