Zeitschrift fur experimentelle Chirurgie最新文献

A conglomerate of homologous bone-chips and n-butyl-cyanoacrylate fixes the fragments in the ultrasonic osteosynthesis. The sound pressure leads to the forced penetration of the monomer into preformed gaps of the bone surface (Volkmann and Haversian canals) up to maximum 300 microns during the polymerisation forced by ultrasound. A toothing effect between the conglomerate and the cortex takes place in this way, this one leads to a higher mechanical resistance and to specialities in the regenerative process. The term welding is founded scientifically by the mechanism of the connecting formation. On the other hand the application of the ultrasound is sensible in order to force the polymerisation.

The epicardium as a biological substrate is able to absorb. We were able to observe the absorption of pharmacological substances and the physically dissolved oxygen as well as the gaseous oxygen after the application into the pericardial cavity by experiments in narcotised mini-pigs. The oxygen absorption by the epicardium led to the retrogression of an artificially caused myocardial ischemia.

Lung transplantations were carried out in 20 not immunologically selected mongrel dogs which were pretreated with donor specific spleno-antigen mixture. The average survival time was double the size (12.3 days) as in a control group of untreated dogs after allogenic lung transplantation. A number of the receivers got Cyclophosphamid in addition to the spleno-antigen mixture. In this group the average survival time amounted to 17 days. A chronic course of the rejection was not to be achieved with this method. The autopsy showed thoracic infectious complications in nearly all receivers. A great number of central pulmonary vein thromboses in the transplant was discovered in this series in contrast to other lung transplantation series. Circumstances refer to a connection with hyperacute rejection courses. The receivers of this series survived the destruction of the transplant longer on an average as such in other experimental series.

A two-component polyacrylic amide gel forming a net-like structure was built up on pancreatic cells. In such a way the transplanted cells could be protected from the damage by immune protein with big molecule. The method was tested in yeast cells before, human erythrocytes, and wether erythrocytes. It was shown that the polymerisation and the inclusion method do not influence essentially the vitality of the examined cells. It was demonstrated by means of the complement fixation reaction that the included erythrocytes cannot be damaged by the immune protein with big molecule. Metabolic processes of the included pancreas beta cells were provable by diffusion. The experiments promise that the included cells survive after the transplantation and the polyacrylic amide gel protects the cells from the impairing effect of the immune protein.

The determination of the concentration in acetate puffered methanol solutions (formaldehyde solutions) with pH = 5.60 during 14 months disproved the opinion of the limited durability of these solutions. Neither a significant decrease of the methanal mass concentration nor a noticeable change of the pH value could be proved during the period of the examination under different influences of light and temperature. Methanal solutions can be applied farther in the practice of the preservation.

Methanal (formaldehyde) preserved and ethane acid peroxide finally sterilised aortic segments showed in vitro and in vivo a significant decrease of the material characteristics in case of watering for 180 days. Intraperitoneal incorporation in a xenogeneous animal species during 60 days reduced the mechanical stability of the substitutes without long-term watering and also with long-term watering, but with an additionally greater negative effect.

The investigation of bioactive materials in the subcutaneous tissue of the rat is a method of the biocompatibility testing of newly developed bio-vitrokerame. The histological assessment of the course of wound healing was the base of the evaluation after a period of 40 days. An extensively concluded cellular reaction and the formation of a thin fibrous capsule can be judged positively with aluminium oxide ceramics and beta tricalcium phosphate. Bioactive materials of a determined combination can arise problems.

The influence of serum factors on the antibiogram was investigated in 21 patients. The plate culture and the culture in tubes were used in combination. A different interaction of the 4 examined antimicrobiotics (gentamycin, chloramphenicol, ampicillin, and nitrofurantoin) with the serum factors was shown which were modified by the duration of the infection (pyelonephritis).