FIG. 1.

Frequency of gallbladder signals upon intravenous infection with L. monocytogenes. Twenty female CD1 outbred mice (25 g) were infected intravenously via the tail vein with 6 × 10⁴ CFU of virulent L. monocytogenes strain 2C and imaged 2 days later. This dose in 25-g CD1 female mice is fatal after 5 to 6 days. The scale bar indicates pseudocolor representation of photon counts detected during the 5-min exposure. The characteristic isotropic signal from the lower thorax of the animal originates from the gallbladder.