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Biomedical subjects

R Whitehead

Publications and source records attributed to R Whitehead.

At least 109 records · Page 6Linked to original sources
PubMed1972

ABO blood groups, rhesus factor and intestinal metaplasia of the stomach.

The presence or absence of intestinal metaplasia of the stomach was determined in 272 patients by direct vision biopsy of standardized intragastric sites using fiberoptic gastroscopy. Analysis of ABO blood groupings and Rhesus factor failed to reveal an association with metaplasia.

ABO Blood-Group System↗
PubMed1972

Ultrastructure within the lateral plexus of the Limulus eye.

The ultrastructure of the lateral plexus in the compound eye of Limulus is investigated by serial section technique. "Cores" of tissue containing the axons, lateral plexus, and neuropile associated with one sensory ommatidium show the following features: (a) collateral branches from retinular cells do not contribute to the lateral plexus proper, but do form retinular neuropile by contacting collaterals of a self-contained cluster of retinular axons; (b) collateral branches from eccentric cell axons always branch repeatedly upon leaving the parent axon, and compose the bulk of the lateral plexus; (c) the most distal collateral branches from an eccentric cell axon appear to form neuropile and synaptic contacts with each other, whereas more proximal branches form synaptic contacts with collaterals from eccentric cell axons of neighboring ommatidia. We conclude that the ribbon synapses and associated transmitter substance in eccentric cell collaterals must be inhibitory, and that two pathways for self-inhibition may exist. We suggest, as a working hypothesis for the structure of the lateral plexus, a branching pattern with depth that mirrors the horizontal spread of lateral inhibition measured physiologically.

Animals↗
PubMed1972

The histological diagnosis of chronic gastritis in fibreoptic gastroscope biopsy specimens.

The advent of the fibreoptic gastroscope with biopsy facilities has provided the means of obtaining biopsy specimens under direct vision from any part of the stomach. This creates new opportunities for the study of chronic gastritis, and, in particular, its evolution, topographical location, and causal relationships. On the basis of an experience with more than 2,500 biopsy specimens we have outlined a method for their systematic examination and have proposed a classification of chronic gastritis. This classification includes the type of mucosa, the type and stage of activity of the gastritis, and the presence and type of metaplasia. The classification is sufficiently flexible to allow within it quantitative assessment of individual histological features.

Biopsy↗
PubMed1972

A method for the quantitation of small intestinal biopsy specimens.

A simple method is described for the quantitative examination of small intestinal mucosal biopsies involving the determination of an index related to the surface-to-volume ratio of the mucosa. The method is of value in distinguishing minor degrees of villous abnormality and will prove useful in comparing serial changes in a given patient. It will also allow comparisons to be made between biopsies taken in different medical centres.

Atrophy↗
PubMed1971

Ischaemic enterocolitis: an expression of the intravascular coagulation syndrome.

In 20 cases of ischaemic enterocolitis unassociated with lesions of major vessels, fresh thrombi were found in the small vessels of the bowel wall and were widespread in other tissues. The capillaries of the renal glomeruli and vessels in the lung were the commonest sites. Pseudo-membranous enterocolitis is shown to be an early or more slowly evolving but identical entity to other forms of so-called ischaemic enterocolitis. This is a condition which includes ischaemic enterocolitis, postoperative enterocolitis, necrotizing enterocolitis, and probably some cases of clostridial and staphylococcal enterocolitis. It is due to an episode of intravascular coagulation occurring principally in the gut wall but also elsewhere.

Adult↗