Cover: Representative histology and ultrastructure of liver of LPS-treated rats. Effect of LPS treatment on liver histology. (a) Day 0: Control liver section. No significant structural abnormalities noted. (b) Day 1: Liver section shows a necrotic focus (arrow) with rim of scattered inflammatory cells. (c) Day 2: Note the increase in mitotic figures (arrowheads). (d) Day 5: Liver section shows the presence of a few infiltrating mononuclear cells and scattered mitotic figures. This figure represents one of four independent experiments. (H&E stain; original magnification, {times}300.) For more information see article by Suliman and colleagues beginning on page 570.