局部去极化电紧张电位可以叠加而增大,一旦达到阈电位水平则产生扩布性兴奋
参考答案:对
I forgot to bring a pen. Would you lend me ____? [ ]
A. one
B. that
C. it
D. this
配合公差的大小,等于相配合的孔轴公差之和。