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R Hebel

Publications and source records attributed to R Hebel.

At least 37 records · Page 2Linked to original sources

Distribution of retinal ganglion cells in five mammalian species (pig, sheep, ox, horse, dog).

In order to ascertain shape and location of the central area, the distribution of ganglion cells was measured in whole mounts of the retina from pig, sheep, ox, horse, and dog. Although exact comparison of corresponding points of measurement in different animals was not possible, the measurements allowed the mapping of retinal ganglion cell density, typical for the particular species. In all ungulates a streak of high cell density extends along a straight horizontal line, dorsal to the optic disc. As a rule a maximum of ganglion cell density is found close to the temporal end of the visual streak. In the dog a well demarcated oval portion of the streak continues into a short temporal (variable) and a long nasal linear arm. The functional significance of these findings is discussed.

Animals↗

Ischemic carotid endothelium. Scanning electron microscopical studies.

The normal luminal surface and the effect of ischemia on the endothelium of the common carotid arteries of rhesus monkeys were examined by scanning electron microscopy. Clamps were placed proximally and distally on the right common carotid arteries, totally occluding the vessels for periods ranging from five minutes to four hours. The clamps were then removed and fixation carried out by intravascular perfusion. The contralateral sham-operated carotids, as well as those from unoperated animals were used as control specimens. The most obvious effect of ischemia was the appearance of conical, crater-like defects in the cytoplasm of endothelial cells. Such "craters" were observed following as little as 15 minutes of ischemia, were much less frequent in sham-operated vessels, and were not seen in the unoperated control specimens.

Animals↗