A manual of human physiology, including histology and microscopical anatomy, with special reference to the requirements of practical medicine (1885) (14778451651)

Identifier: manualofhumanphy01land (find matches)
Title: A manual of human physiology, including histology and microscopical anatomy, with special reference to the requirements of practical medicine
Year: 1885 (1880s)
Authors: Landois, L. (Leonard), 1837-1902 Stirling, William, 1851-1932
Subjects: Physiology Histology
Publisher: Philadelphia, P. Blakiston, Son, and Company
Contributing Library: MBLWHOI Library
Digitizing Sponsor: MBLWHOI Library



Text Appearing Before Image:
end of each cell is open, and from it there projects pseudo-podia-like bundles of protoplasmic processes (Fig. 150, B). These processes aresupposed to be extended beyond the margin of the cell and again rapidly retracted,and in so acting they are said to carry the fatty particles into the interior of thecells, much as the pseudopodia of an amoeba entangles its food. (This view hasnot been confirmed by a sufficient number of observers.) Between the epithelialcells are the so-called goblet-cdls (Fig. 150, C). (Each goblet-cell is more~or less 388 STRUCTURE OF A VILLUS. like a chalice, narrower above and below, and broad in the middle, with a taperingfixed extremity. The outer part of each cell is filled with a clear substance ormucigen, which, on the addition of water, yields mucus. The mucigen lies in theintervals of a fine net-work of fibrils, which pervades the cell protoplasm. Theprotoplasm, containing a globular or triangular nucleus, is pushed into the lower part B o•« .••a
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Fig. 150. .Scheme of an intestinal villus—A, Transverse section of part of a villus ; a,columnar epithelium with, b, clear disc; c, goblet-cell; i, i, adenoid reti-culum ; d, d, spaces within the same and containing leucocytes, e, e; f, sectionof the central lacteal; B, scheme of a cell with processes supposed to beprojected from its interior; C, columnar epithelium after the absorption offatty granules; D, the columnar epithelium of a villus seen from above witha goblet-cell in the centre. of the cell. These goblet-cells are simply altered columnar epithelial cells, whichsecrete mucus in their interior. They are more numerous under certain conditions.Not unfrequently in sections of the mucous membrane of the gut, after it is stainedwith logwood, we may see a deep blue plug of mucus partly exuded from thesecells. When looked at from above they give the appearance seen in Fig. 150, D.)The epithelial cells are shed in enormous numbers in cholera, and in poisoningwith arsenic and musca