热解吸-气相色谱法测定室内空气中总挥发性有机物时，采样后将吸附管取下，密封采样管，样品可存放（）d。
A.4
B.7
C.10
D.14
参考答案：D
______ the same story many times, my little brother can now tell it himself.
A．Telling
B．Having told
C．Being told
D．Having been told
患者男性，45岁。因腹痛、寒战高热、黄疸入院。
该患者首选的辅助检查是（）.
A.CT
B.PTC
C.MRI
D.ERCP
E.剖腹探查
F.B超
