For me,I walked into a bead store and the girl showed me how to put bead and chain together, worked a few wire techniques.

VOA: special.2009.05.18

They also have binding sites for antigen, but they are sort of two IgG type molecules bound together by another peptide chain.

同样IgA抗体表面也有与抗原结合位点,但它们就像两个IgG型分子,通过肽链相互连接

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