Routine genotyping was performed using PCR 4 min denaturation at 98 C, followed by 25 cycles consisting of 30 s denaturation at 98 C, 30 s annealing at 69 C, and 25 s extension at 72 C using iProof kit from Bio Rad with the following 2 primers 21M loxp1 sequence sense CTGTTGGTGTCAGTTCTTGCAGATG, in intron 20 and 21M sequence loxp2 antisense CAAGGATGCTGGCCATTGAATGGCTTC, in exon 21 cialis for sale in usa Zhao Ling entered a state of searching