下列有关脊柱的描述哪项错误()
A.仰卧位时L最高
B.由椎骨以及椎间盘、椎间关节、韧带等连接装置组成
C.仰卧位时T6最低
D.椎管内有三个潜在的腔隙
E.有四个生理弯曲
参考答案:A
The survey shows that ______ we are enjoying less and less good sleep, rates of heart diseases have risen rapidly.
A.while
B.although
C.if only
D.as though
属于变压器定期取油样化验的项目()
A、酸价
B、电气绝缘强度
C、闪光点
D、游离碳