The invention relates to a method for exchanging messages in a mobile radio system by means of a convergent messaging system, which allows an exchange of messages between the terminals of two or more users. The organic molybdenum compounds can be represented by the general formula which is indicated below,wherein A1 and A2 are heterocyclic rings which may have substituent groups. A forked portion formed of a combination of the guide piece and the engagement part. The invention is also directed to a method of producing said tissue matrix and to the use thereof, as well as to the autologous graft produced therefrom, and to the production and use thereof.