Human body is a conductor, not only conducts heat and electricity, but also qi and blood. Channels and Collaterals is the pathway of qi and blood. The function of qi and blood of Zang and Fu is depended on the flow of qi and blood through the Channels and Collaterals. If the pathway is obstructed, stagnation of qi and blood occurs, and the related location and organ are out of condition. The principle of treatment is
　　 dredging the channel. For example the reason of pain is the channel obstructed and removing obstruction in the channel can relieve pain. In clinic dredging the channel is very effective to relieve pain.

By Xia Jim.
　　Long Life Chinese Medical Center and Research institute 20444 Lake Chabot Road, #5 Castro Vally, CA 94546, U.S.A.