Resonance phenomena in cell population chemotherapy models

A drain clip and method for making a drain clip for use in circumposed relation about a surgical drain of tubular rubbery material. The clip has a) an elongate base of rigid material preferably in sheet form with a smooth main surface to be positioned in overlaying relation of an incision line and with a drain tube opening, and b) one-way gripping means on the base with a terminal surface extending into the opening and away from the smooth main surface which overlays the incision. The gripping means comprise a plurality of spaced shallow gripping teeth arranged in a pattern and defining a constricted drain passage between the teeth. When the clip is circumposed about a surgical grain extending from an incision, the drain is adapted to be advanced as the healing process takes place while retractive movement of the drain toward the incision will be resisted by the gripping means.