《铁路线路修理规则》规定的接头阻力C值包含钢轨与夹板之间的磨阻力和螺栓的抗剪力。
参考答案:错
To keep healthy,Professor Johnson _______ cycling as a regular form of exercise after he retired.
A.caught on
B.set out
C.made for
D.took up
目前临床上常用的检测乙型肝炎最常用方法是
A.免疫电镜检测粪便标本中病毒颗粒
B.RIA和ELISA检测患者血清中HBV抗原抗体
C.直接分离培养
D.PCR检测血液中HBV抗原抗体
E.ELISA检测患者血清中HBV抗原