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Biomedical subjects

H Weiss

Publications and source records attributed to H Weiss.

At least 415 records · Page 23Linked to original sources
PubMed1976

[Experimental siderosis bulbi: an echographic-histological study (author's transl)].

In 20 eyes of 10 rabbits a siderosis was provoked by intravitreal injection of 0,1 ml of a 1% watery solution of Mohr's salt. The course of the following vitreous retraction was observed during 4 weeks by means of ultrasonography, and each echogram was compared with the corresponding histological finding. The results of these investigations show that by means of ultrasonography vitreous destruction or liquefaction can be ascertained and distinguished from an undulation, taught or funnel-shaped detachment of the posterior hyaloid membrane; in addition, this membrane and retinal detachments are well discernible by this method.

Animals↗
PubMed1976

[The influence of the retina on the maturation of the testicles: an experimental study in rabbits (author's transl)].

In the present experimental study in rabbits the importance of the non-illuminated retina as a superior regulating centre for the maturation of the testicles is demonstrated. Involvement of the retinal maturation by an experimentally provoked total retinal detachment is followed by a cessation of the development of the testicles. The extent of this influence can be brought in evidence by means of the quotation of the fatty acids C20:4/C22:5 as well as on the hand of the histological findings.

Animals↗
PubMed1976

[Changes of the phosphatides and their fatty acids in the retina and in the fasciculus opticus after retinal detachment: investigations of human and animal retinae (author's transl)].

In this study the effect of an experimentally provoked retinal detachment on the pattern of the phosphatides and fatty acids of the retina and the optic nerve of adult rabbits was investigated. The analysis was performed one month, and 4 months after the operation, and the values were related to the findings in control animals of the same age, and of the age of one day and 30 days respectively. In this way changes in the total lipide, in the phosphatides and in their fatty acids could be revealed, with a tendency towards the developmental stage of the 20th up to the 30th day of life. Between retina and optic nerve no difference was found neither temporally nor regarding the quantitative reaction. In the detached human retinae the same reactions can be proved as in the animal experiment. The relationship of these findings to the recovery of the operatively reatached human retina is discussed.

Adult↗
PubMed1976

Irradiation of cells by single and double pulses of high intensity radiation: oxygen sensitization and diffusion kinetics.

The biological effects of ionizing radiation in living cells are the ultimate result of a long chain of events with the initial step being the local absorption of radiation. Whereas such physical abosrption is probably over within 10(-16) s after dose delivery, the biological consequences of radiation do not manifest themselves until very much later times. Between these two extremes of time, events occur relatively early at the molecular level which are undoubtedly critically related to the still unknown basic mechanisms of cellular radiation damage. These events may include not only the interaction of highly reactive species produced within the cell but also the diffusion of molecules such as oxygen or other chemical radiosensitizers.

Bacteria↗
PubMed1975

[Lesion of the retinal fatty acids following intravitreal injection of iron. An experimental study on the retinal lesions in cases of siderosis bulbi (author's transl)].

In this study the alterations of the pattern of the fatty acids of the retinal phosphatides after intravitreal injection of ferrous ammonium sulphate are treated. In vitro and in vivo a significant decrease of the highly unsaturated fatty acids of the C22 type occurs. This lesion spreads from the region of direct contact between iron and retina towards the periphery within 24 hs. The reliability of the experiment is ensured by the proof of analogous changes in human globes affected with siderosis. Finally, the production of lipid peroxides as a cause of the breakdown of the retinal function is discussed.

Animals↗
PubMed1975

[A light-independent function of the retina of rabbits. Examination on the energetic part of the visual pathway (author's transl)].

In this study a light-independent function of the retina of rabbits could be proved. For this purpose, the energetic part of the visual pathway was utilized, and its influence on the maturation of the testicles was examined. As a criterion of maturation, the pattern of the phosphatid-fatty acids was ascertained. The subdivision of the energetic part of the visual pathway into a photo-energetic and an autonomic-energetic component is proposed.

Animals↗
PubMed1975

[A clinical experimental study on the therapeutically effective component of retinal phosphatides (author's transl)].

In the present study it was demonstrated that neither the relation of the single phosphatide components nor the organ which serves as the source of the phosphatides have any importance on the therapeutic effect on the retina. The therapeutic effect of the phosphatide depends on their content of C 22:6. The phosphatide complex from livers of pigs, feeded with fish, has a particularly high content C 22:6. Its therapeutic effect and its production offers great technical and economical advantages.

Animals↗