蛋白质具有紫外吸收的性质,检测波长是
A.270~290nmB.290~340nmC.250~270nmD.340~360nmE.360~400nm
参考答案:A
Our teachers __________ the same clothes when they are at school.
A.put on
B.wear
C.dress
D.pull on
试述改良J-G法测定血清胆红质的基本原理。