[Methods for the preservation of soft tissue preparations for clinical use].

The demand for consistent supply of nonvital allogenous implants in tissue banks has the supposition for graft preservation. Besides of many logistic advantages the preservation methods are accompanied by the influence of original attributes, especially of biomechanic parameters in soft tissue preparations. A procedure of dura mater preparation, of fascia lata, tendons and skin is demonstrated which is preserving the required qualities of plasticity, softness and resistance.

[Relevant laboratory diagnostic methods for the evaluation of the osteoinductivity of bone matrix implants].

For the valuation of the osteoinductive efficacy of different bone grafts bears upon increasing the determination of the alkaline phosphatase, the content of calcium, hydroxyproline and protein. We could prove the quantitative differentiation of different prepared bone matrix implants being possible, nevertheless the histological examination is an unavoidable, full of good sense completion.

[A method for the preparation of demineralized bone matrix].

A procedure for preparation of a demineralized bone matrix (DBM) implant is demonstrated. The main steps of this method are refrigeration, milling/sieving, defatting, demineralization, freeze-drying and sterilization. These steps are standardized but also viable.

[Population genetic studies in Ethiopia: distribution of blood group polymorphisms in Amhara/Tigrai ethnic groups].

During 1981-1982 and 1983-1984 a population-genetic study has been performed in the Amhara/Tigrai ethnic groups of Northwestern Ethiopia (Gondar). Blood group frequencies are reported for 6 systems (AB0, MNSs, Rh, P, Kell, Kidd), secretor status, haptoglobin, Gc, Gm/Km, HLA-A and -B as well as for the erythrocytic enzyme polymorphisms AcP, PGM1, ADA, EsD, GPT, AK and GLO I. The results are compared with other reports from East Africa and the Arabian peninsula.