内脏痛觉有何特点?
参考答案:
(1)缓慢持续,定位不精确;
(2)伴随不安与恐怖感;
(3)对牵拉、缺血、痉挛、炎症敏感,对切割、烧伤不敏感;
(4)有牵涉痛。
超导体的同位素效应
It is not until you have lost your health()you know its value.
A.until
B.when
C.what
D.that