Farrar W E
Clin Invest Med. 1983;6(3):213-20.
Molecular biological techniques, including agarose gel electrophoresis, restriction endonuclease analysis and DNA-DNA hybridization (Southern blotting and heteroduplex analysis) are being applied very successfully to the investigation of nosocomial infections. 'Plasmid fingerprinting' by electrophoresis, with or without restriction endonuclease analysis, can be used to identify epidemic strains of bacteria and 'epidemic plasmids' which have spread through several different bacterial species. This technique is rapid and inexpensive, and can be applied to drug-sensitive as well as resistant strains. This approach is especially useful for investigation of organisms for which no standard typing system is available. DNA-DNA hybridization techniques can be used to study the evolution of plasmids in the hospital environment, and to demonstrate the presence and spread of translocatable DNA sequences (transposons) carrying drug resistance determinants from plasmid to plasmid within a bacterial cell.
分子生物学技术，包括琼脂糖凝胶电泳、限制性内切酶分析以及DNA-DNA杂交（Southern印迹法和异源双链分析），正非常成功地应用于医院感染的调查。通过电泳进行“质粒指纹图谱分析”，无论是否进行限制性内切酶分析，均可用于鉴定已在几种不同细菌物种中传播的细菌流行菌株和“流行质粒”。该技术快速且成本低廉，可应用于药敏菌株和耐药菌株。这种方法对于没有标准分型系统的微生物的调查尤为有用。DNA-DNA杂交技术可用于研究医院环境中质粒的进化，并证明携带耐药决定簇的可转移DNA序列（转座子）在细菌细胞内从一个质粒到另一个质粒的存在和传播。
