下列哪种免疫球蛋白在特应性过敏症患者血清中浓度可升高（）.
A.IgG
B.IgA
C.IgM
D.IgE
E.IgD
参考答案：D
What term indicates the line drawn at the top of the flat plate keel（）.
A.Base line
B.Molded line
C.Designer's waterline
D.Keel line
静电除尘器自动电压调整器中为什么要串接电抗器，其串接方式如何？
