心血管系统在应激时的基本变化为心率(),心肌收缩力(),心输出量()。
参考答案:增快;增强;增加
—How was your journey last week?
—Very interesting. The people there still keep the custom _____ the Ming Dynasty, which is different from other areas.
A.dating back to
B.dating back
C.dated back to
D.dated back
电动吊篮应安装上、下限位装置。()