FIG. 1.

Agarose gel electrophoresis (ethidium bromide stain) of PCR products. (A) First round of amplification; (B) double PCR amplification. Lanes 1 and 2, fresh sample; lanes 3 and 4, specimen in 2.5% potassium dichromate solution; lanes 5 and 6, formalin-fixed sample; lanes 7 and 8, specimen preserved in MF. Lanes 1, 3, 5, and 7, homogeneous suspension; lanes 2, 4, 6, and 8, concentrated sample. Lanes 9 and 10, positive and negative controls, respectively; lane 11, reaction mixture; lane M, 100-bp ladder.