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Biomedical subjects

D W Mann

Publications and source records attributed to D W Mann.

25 records · Page 2Linked to original sources
PubMed1976

Differential survival of isolated portions of crayfish axons.

Electron microscopic studies show that transplanted segments of sensory axons of varying lengths degenerate within 7-14 days whereas transplanted segments of crustacean motor axons survive morphologically intact for 20-30 days. The middle portion of an isolated motor axon segment degenerates less rapidly than portions of the same axon located nearer the periphery or nearer the ventral nerve cord. One week after transplantation, glial cells appear to phagocytize sensory axons whereas glial cells around motor axons appear to hypertrophy and to have more rough endoplasmic reticulum. After three weeks, motor axons also appear to be phagocytized by glial cells. These data suggest that the glia surrounding isolated motor axons can change from a supportive to a destructive function, whereas glial cells surrounding severed sensory axons primarily have a destructive function. These and other data also indicate that crustacean motor axons receive significant trophic inputs from their own perikaryon, from post-synaptic contacts, and from adjacent glial cells. The possibility that adjacent healthy cells may supply metabolically deficient cells with needed substances could be a significant adaptive advantage for the evolution of multicellular organisms.

Animals↗
PubMedDate not supplied

Theories of the self.

This paper reviews the historical and conceptual development of theories concerning the nature of the self, highlighting both common themes and differences among representative theorists and their systems. The evolution of the concept of the self is traced from its ancient foundations in Vedic thought through its classical period (Socrates) and into the present century, where the work of James, Freud, Klein, Fairbairn, Sullivan, Winnicott, and Kohut illustrate the major modern refinements of the concept. The paper concludes with my own recent work toward a synthesis of these developments.

Ego↗
PubMedDate not supplied

The virtues in psychiatric practice.

Using as a guide Pellegrino and Thomasma's "end-oriented beneficence model" of the virtues in medical practice, the author derives from the cardinal forms of psychiatric treatment a set of virtues particular to this field. Prior work from Jung, Havens and Menzer-Benaron helps to clarify the analysis.

Attitude to Health↗