题型:问答题 As is known to all ,Xi’an was starting point of world – famous Silk Road. A./; /B.a; aC.the; /D.the; the 查看答案
题型:问答题 以下哪项描述是正确的()。A.睡眠时脑活动处于安静状态B.根据电生理变化,睡眠可分为NREM睡眠与REM睡眠C.NREM睡眠时全身代谢活动增强D.REM睡眠可以分为1-4期E.睡眠期间人体始终保持体温调节功能 查看答案