Autonomic modification of intestinal smooth muscle contractility.

Intestinal smooth muscle contracts rhythmically in the absence of nerve and hormonal stimulation because of the activity of pacemaker cells between and within the muscle layers. This means that the autonomic nervous system modifies rather than initiates intestinal contractions. The practical described here gives students an opportunity to observe this spontaneous activity and its modification by agents associated with parasympathetic and sympathetic nerve activity.

Postbiopsy bleeding in a porcine model: reduction with radio-frequency ablation--preliminary results.

Purpose: To test a biopsy needle modified for use of radio-frequency (RF) energy to produce hemostasis after core biopsy of liver or kidney.

Materials And Methods: RF energy was applied to a partially insulated 17-gauge needle, and tip temperature was monitored with a thermocouple. Domestic Yorkshire pigs (n = 4; mean weight, 23.