Tobacco Smoke Filter Material

A tobacco smoke filter comprising a imidazole-containing polymer, the imidazole groups being chemically bound to said polymer

Radiodiagnostic Agent

A radiodiagnostic agent comprising a solid, insoluble nontoxic synthetic resin, such as polystyrene, bearing a detectable amount of technetium 99m thereon. This agent is useful for analyzing the gastrointestinal tract, for example, for gastric emptying time, by means of a gamma camera