最易引起枕骨大孔疝的颅内占位性病变是()
A.蝶鞍区肿瘤
B.额顶叶肿瘤
C.颞叶脑脓肿
D.侧脑室肿瘤
E.小脑半球肿瘤
参考答案:E
He tried to make ______ clear that he did an important job.
A.this
B.that
C.it
D.\
带电作业工具使用前应进行分段绝缘检测(电极宽2cm、极间宽2cm),阻值应不低于500MΩ。