角膜边缘出现Kayser-Fleischer环,原因是()。
A.先天性因素
B.类脂质沉着
C.铜代谢障碍
D.维生素A缺乏
E.角膜血管增生
参考答案:C
The Oregon Trail went through the South Pass,______gold was discovered in 1842.
A.where
B.which
C.that
D.when
人体碰触漏电的焊机外壳发生触电称为直接电击。()