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Immun. 64: 2808 - 2811. 41 PHỤ LỤC HÓA CHẤT CHO ĐIỆN DI TBE (0,5X) Tris HCl 3,94 mg Acid Boric 1,39 mg Na 2 EDTA 93,06 mg Nước cất vừa đủ 500 ml pH = 8,3 Agarose (1,65%) Loading dye Bromophenol blue 0,25% Sucrose 40% TE 1X vừa đủ 100% HÓA CHẤT CHO NHUỘM GEL TBE 1X Ethidium bromide 10 mg/ml MÔI TRƯỜNG VÀ THUỐC THỬ Môi trường Nước pepton đệm Pepton 10 g Sodium chloride 5 g Disodium hydrogen phosphate 9 g Potassium dihydrogen phosphate 1,5 g Nước cất vừa đủ 1000 ml NA Pepton 5 g Sodium chloride 5 g 42 Beef Extract 1,5 g Yeast Extract 1,5 g Agar 15 g Nước cất vừa đủ 1000 ml pH = 7,4 0,2 (25 0 C) MAC Bacto pepton 17 g Bacto Proteose pepton 3 g Bacto Lactose 10 g Bacto Bile salts 1,5 g Sodium Chloride 5 g Bacto agar 13,5 g Neutral Red 0,03 g Bacto Crystal Violet 0,001 g SMAC Pepton 20 g Sodium chloride 5 g Bile salt 1,5 g Sorbitol 10 g Crystal violet 0,001 g Neutral red 0,003 g Agar 15 g Nước cất vừa đủ 1000 ml SIMMON CITRATE Na citrate 2 g NaCl 5 g K 2 HPO 4 1 g NH 4 H 2 PO 4 1 g MgSO 4 0,2 g 43 Bromothymol blue 0,08 g Agar 15 g Nước cất vừa đủ 1000 ml MR – VP Pepton 7 g Glucose 5 g K 2 HPO 4 5 g Nước cất vừa đủ 800 ml pH = 6,9 0,2 Thuốc thử VP (Voges Proskauer) Dung dịch A: Alpha napthol 5 g Ethanol tuyệt đối 100 ml Dung dịch B: Potassium hydroxyde 40 g Nước cất 100 ml MR (Methyl red) Methyl red 0,1 g Alcohol 300 ml Nước cất vừa đủ 500 ml Cấy từng khuẩn lạc được chọn vào t ừng . Multiplex PCR. J. Clin. Microbiol. 3 3: 248 - 250 . 13. Cerna J. F., Nataro J. P., and Teresa Estrada Garcia, 2003. Multiplex PCR for detection of three plasmide borne genes of enteroaggregative Escherichia. identify enterohemorrhagic Escherichia coli of O 157 :H7 and other serotypes that cause hemorrhagic colitis and hemolytic uremic syndrome. J. Infect. Dis. 15 6: 1 75 - 182. 39 34. Leyer G. J.,. Louie M., Wilson J., Lior H., and Gyles C. L., 1996. Prevalence of the eaeA gene in verotoxigenic Escherichia coli strains from dairy cattle in Southwest Ontario. Epidemiol. Infect. 11 6: 1