Biomedical subjects
Publications and source records attributed to P Roll.
Three areas in which zonular fibers of Zinn enter were demonstrated with the aid of scanning electron microscopy. 1. The area, which applied to the edge of the lens. 2. The area of Pars plicata corporis ciliaris. 3. The area of Pars plana. The connection of zonuar fibers with limited membran of vitreous body was presented too.
Single zonular fibers could be shown in the area of ora serrata and the peripheral parts of retina between the basement membrane of pigmented epithelium and the elastic tissue of Bruchsmembran. The occurrence of fibroblasts in the proximity of zonular fibers was noticeable.
The course of zonular fibers in the area of pars plicata corporis ciliaris could be shown down to the pigmented epithelial layer and its basement membrane. S ingle fibrils enter in a connection with the plasma membrane in allinvestigated parts. Fibrils could be observed in the cytoplasm of the ora serrata. For the other areas (pars plicata corporis ciliaris, parsplana) this can be suggested too.
Zonular fibers could be shown between the basement membrane of the pigmented epithelium of pars plana and the elastic tissue of Bruch's membrane. A connection of zonular fibrils between the unpigmented epithelium and the basement membrane of pigmented epithelium of the pars plana could not be observed. It is possible to discuss two independent courses of zonular fibers.
Examination of the ultrastructure of cases of spotty corneal dystrophy (Groenouw II) showed polymorphous results in various layers of the cornea. Inclusions of acidic mucopolysaccharides occur in membrane surrounded storage granules and also in the free state. The results from sections of the central and peripheral regions are extraordinarily variable. The present investigations showed for the first time, that numerous vesicular inclusions can occur also in the boundary region between the stroma and Descemet's membrane.
Based on the results from semistructured interviews with parents of fifty SIDS victims and of fifty matched controls we developed a SIDS risk questionnaire, the so-called SRFB Graz. In a retrospective study this questionnaire was applied to 65 SIDS victims and 195 comparable controls. By statistical analysis a cut point was computed, which discriminates SIDS cases from controls with a sensitivity of 86% and a specificity of 95%.
The skin of Helix pomatia was investigated by biochemical methods and electronmicroscope. Biochemical investigations showed that Helix pomatia collagen represents a methionine-lacking collagen resistant to CNBr-cleavage. Electron microscopic studies showed a cross striation pattern of 53--57 nm.
The authors tested whether use of an electro shock weapon (stun gun) leaves marks on skin which can be found in an exterior examination. On pig skin such marks could not be produced postmortally. An experiment on one of the authors caused reddish skin marks which persisted for about 2 h. Inability to act as promised by the weapons' manufacturers did not occur in our experiments, exactly as previously described by other authors. Use of an air tester which shoots barbed electrodes ought to produce bleedings if the electrodes actually penetrate the skin.
During a sailing maneuvre the mast of the boat was brought into contact with a high-voltage transmission line; the metal parts of the boat caused a ground connection into the water. At first, the four men on board the boat attempted to interrupt the flow of electric current. In doing so, one of them got into the electric circuit and became unconscious. A second sailer jumped into the water, in order to save his unconscious colleague by pulling him ashore. This attempt, however, was not successful. Only the bodies of the two sailors could be recovered by divers. The forensic findings concerning each of the two bodies, as well as the results of an on-the-spot examination done with the help of the two survivors of the accident, are discussed with emphasis on the electrophysical laws related to the causes of death.