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Biomedical subjects

R D Harkness

Publications and source records attributed to R D Harkness.

At least 19 recordsLinked to original sources
PubMed1978

Digestion of native collagen in the gut.

The digestion and absorption of collagen, native and artificially cross-linked, has been examined in the rat and the Gaboon viper, by feeding known quantities and measuring the hydroxy-proline content of the faeces and of the contents of the gut at different levels, and comparing with an unabsorbable marker (polyethylene glycol). Incubation of collagen in vitro with pepsin at 37 degrees C at pH 1.5 followed by trypsin or chymotrypsin converted about 40% into dialysable material.

Animals↗
PubMed1975

The structure of the tapetum of the eye of the sheep.

The structure of the tapetum of the sheep's eye has been examined by transmission electron microscopy. It consists of regularly arranged layers of collagen fibrils, estimated from the hydroxyproline content to make up about 60 percent of the dry weight of the tissue. There are several hundred of these layers in the whole depth, a majority being oriented in the same direction. The collagen is associated with strands of microfibrillar material as well as with cells of both fibrocyte and smooth muscle types.

Animals↗