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Biomedical subjects

E Neumann

Publications and source records attributed to E Neumann.

At least 199 records · Page 11Linked to original sources
PubMed1975

Myopia-aphakia. II. Vitreous and peripheral retina.

Biomicroscopical examination of the vitreous and peripheral retina was performed on 103 aphakic eyes with myopia of at least -6-0 dioptres. Retinal breaks were found in 19 eyes (18-4 per cent). Posterior vitreous detachment was present in all but one of the eyes. The high prevalence of retinal breaks in aphakic eyes with high myopia is compatible with the high incidence of retinal detachment in such eyes.

Adult↗
PubMed1975

Nerve excitability--toward an integrating concept.

Although numerous experimental data have been accumulated in the various fields of research on bioelectricity, the mechanism of nerve excitability is still an unsolved problem. Many mechanistic interpretations of nerve behavior cover only a part of the facts, are thus selective and unsatisfactory. An attempt at an integral interpretation of basic data well-established by electrophysiological, biochemical, and biophysical investigations was inspired by the late Aharon Katchalsky and a first attempt had been made previously (Neumann et al., 1973). The present account is a further step toward a quantitative physiochemical theory of bioelectricity. We have further explored the previously introduced notion of a basic excitation unit in excitable membranes. This notion is of fundamental importance for modeling details of sub- and suprathreshold responses, such as threshold behavior and strength-duration curves, in terms of kinetic parameters for specific membrane processes. Our integral model of excitability is based on the original chemical hypothesis for the control of bioelectricity (Nachmansohn, 1959, 1971b). This specific approach includes some frequently ignored experimental facts on acetylcholine-processing proteins in excitable membranes. According to the integral model, acetylcholine ions are continuously processed through the basic excitation units within excitable membranes: axonal, presynaptic, and postsynaptic parts. Excitability, i.e., the generation and propagation of nerve impulses, is due to a cooperative increase in the rate of AcCh translocation through the cholinergic control system.

Acetylcholine↗