慢性心房颤动病人电复律治疗最易并发脑梗死的时间是术后（）
A.2小时
B.4小时
C.24～48小时
D.72小时
E.96小时
参考答案：C
Which reason for purchasing U. S. Treasury securities is least valid（）
A. Coupon strips synthesize a zero-coupon bond.
B. Treasury-bonds are available in maturities of two years to nearly 30 years.
C. Treasury Inflation Protection Securities (TIPS) raise their principal value to adjust for inflation.
全挂列车倒车，要避免牵引车与挂车形成较大的角度。
