安全检验合格标志的有效期自签发验收检验或者定期检验合格报告之日起计算。
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轻轻拉动安全带，安全带能够自由拉出无卡滞，快速拉动安全带，安全带应锁紧。（ ）
A. 对
B. 错
用95牛顿米的检查护顶架与挡货架固定螺栓架是否松动。（ ）
A. 对
B. 错
Each statement is right about spirochete EXCEPT ___.
A. It is Gram-negative bacteria.
B. It is thin, tightly coiled, helically shaped.
C. It can corkscrew and burrow through their hosts’ tissues.
D. Its axial fimbria can rotate.
Which one does not belong to the group of spiral bacterium?
A. Vibrio cholera;
B. Helicobacter pylori
C. Psuedomonads ;
D. Treponema palidum;
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