Polymerase chain reaction (PCR) was used to amplify the region of V K and V H from Fab of SZ51, and scu PA 32k(leu144 l eu411) from urokinase gene, respectively.

• 通过聚合酶链式反应（PCR），分别从SZ51的Fab片段基因中扩增出VK和VH区； 从尿激酶原基因中扩增出scu?PA?32k基因。