TUNEL assay for detection of the effect of Cd on hepatopancreas apoptosis in <i>S</i><i>. henanense</i> (<i>n</i> = 4).

<p>(<b>A</b>) Control group. (<b>B</b>) 3.56-mg/L group. (<b>C</b>) 7.12-mg/L group. (<b>D</b>) 14.25-mg/L group. (<b>E</b>) 28.49-mg/L group. (<b>F</b>) 56.98-mg/L group. The apoptotic cellular nucleus was stained brown, ×600. The positive cells were dispersedly distributed or clustered.