The active fragment consisted of two peptide chains linked by two disulphide bridges, comprising 26 and 9 amino acid residues with Ser and Phe as the Nterminal, Leu and Hse as the C-terminal residues respectively.

• 此活力碎片是由两条肽链所组成,通过两对二硫键相连结,它们分别含26及9个氨基酸残基,N末端分别为丝氨酸及苯丙氨酸,C末端分别为亮氨酸及高丝氨酸。