链球菌引起化脓性病灶脓汁稀薄且易扩散,其主要原因是病原菌能产生()
A.透明质酸酶
B.血浆凝固酶
C.链激酶
D.链道酶
E.溶血毒素
参考答案:A, C, D
He has work to do, so he can’t go with you.
A.much too
B.many too
C.too much
D.too many
对H2O的电离平衡不产生影响的粒子是( )
A.HCl
B.Na
C.NaCl
D.NaHSO4