Human cyclin - a - compositions, methods for their preparation, nucleotide sequence, a method and active ingredients for the determination or diagnosis of cell multiplication, a method and active ingredients for the inhibition of cell multiplication

摘要

Silver sulphide crystalline membrane for the determination of silver ions or halide ions in solution and method of production. According to the invention, the membrane comprises silver sulphide doped with an ion capable of forming, either with Ag+ or with S2-, a salt presenting a much higher degree of insolubility than chemical species in solution. Preferably, the membrane also contains an inert hydrophobic compound. The membrane is prepared by co-precipitation of the silver sulphide and the doping agent, homogenizing with the hydrophobic compound and then pressing. The membrane may be used in an electrode for the determination of silver or halide ions in solution.