A 230 bp fragments of rpoB were amplified from all M. tuberculosis strains and 113 of 135 (83.7%) sputum samples that were positive for acid fast stain, but not from 16 species of nontuberculosis bacteria and sputum from nontuberculosis patients.

• PCR从所有 2 12株结核分枝杆菌中均扩得 2 3 0bp片段 ；13 5份抗酸染色阳性的痰标本中 ；有 113份扩得阳性片段 ( 83 .；7%25 )。