Differential display PCR(dd PCR) was used to detect the different gene expression level of two groups of cultured cells from dorsal root ganglia(DRG), one treated with "Nerve Regeneration Factor" and the other not.

The general principle and process of DD PCR,as well as the progress of its application in crops environment stress were summarized.

Using DD mixture to synthesize 3-chloro-2-propenyl acrylate;