973 resultados para Francis Webb


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The endocrine pancreas of the rock bass (Ambloplites rupestris) was examined by light and electron microscopy. Two cell types with staining properties similar to mammalian A and B cells, and a third, non-staining cell type were found in the spherical pancreatic islets that were surrounded by a connective tissue capsule and embedded in two small masses of exocrine tissue. From an analysis of the ultrastructure of the A and B cells, a secretory cycle for each of these cell types was proposed. The secretory cycle of the A cell consisted of three well defined stages: (1) A cell production stage: during which A granule formation occurred in the sacs of the Golgi apparatus and the cell was characterized by the presence of numerous secretory granules, some elements of lamellar endoplasmic reticulum, and a homogeneously granular nucleus. The cytoplasm contained few distended cisternae, variable numbers of free ribosomes, microtubules and small vesicles. (2) A cell release stage: during which the release of A granules occurred and the cell usually contained several large distended cisternae and variable numbers of secretory granules. Granule release mechanisms included exocytosis, by which individual granules were released into the extracellular space after their membranes fused with the plasmalemma, and emiocytosis, by which one or more granules were released into a large cisterna whose membrane fused with the plasmalemma and formed a pore through which the cisternal contents passed out of the cell. (3) A cell reorganization stage: during which the changeover from the release stage to the production stage occurred and the reorganization of organelles and membrane structures took place. The cell contained few secretory granules and numerous small endoplasmic reticular cisternae. The cytoplasm exhibited less electron density than either of the other two stages. The A granule after formation underwent a series of morphological changes which were described in four numerically identified phases. The secretory cycle of the B cell consisred of two stages: (1) B cell production stage: during which the B granule formation occurred in the sacs of the Go1gi apparatus. The cell was characterized by an irregular outline, the presence of numerous secretory granules, and an irregularly shaped nucleus which contained variable amounts of clumped chromatin. The cytoplasm contained moderate amounts of lamellar endoplasmic reticulum studded with ribosomes, several small vesicles, and an active Go1gi apparatus. (2) B cell release stage: during which the release of B granules occurred. The cell contained a rounded nucleus with dispersed chromatin, several distended endoplasmic reticular cisternae and a variable number of secretory granules. Granule release occu~ by emiocytosis and exocytosis similar to that found for the A cell.

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Survey map and description of Francis Goring Parnell's land created by The Welland Canal Company. Included is a written description of the land along with a drawing of the land. Noteable features include; line between Widow Secord and Parnell's land, line between Rykert and Parnell's land. The deed for the land is dated December 5th, 1826. The land totals 4 acres, 1 road, and 6 perches. Surveyor notes are seen in pencil on the map.

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Originally published in the Federal Republican of Baltimore. Printed by Benjamin Edes

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A letter from Colonel Albert D. Shaw to Francis Lynde Stetson dated March 31, 1892. The letter is in regards to correspondence with the Attorney General in efforts to expedite the passing of an Act through Ontario Parliament. The act was introduced a week later (April 6, 1892) confirming the agreement between the Queen Vctoria Niagara Falls Park and the Canadian Niagara Power Company.

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Photograph of Francis Bond Head Willson of Beaverdams. He was the great grandson of Thomas and Abigail Willson. The photographer is Geo. Grenville, Artist, Thorold, Ontario. There are two copies of the photograph in the collection and one has the date 1870 handwritten on the back.

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A photograph of Florence Upper, the wife of Francis Bond Head Willson.

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Letter sent to S.D. Woodruff from Francis Lalor regarding the last estimate of work. Mr. Lalor points out some additional work that was done, including: cart-road, culvert excavation and ditching, Mar. 29, 1855.

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Letter which gives an addition to the estimate for work done by John Brown for Dec. 1855. This is made out to S.D. Woodruff from Francis Lalor. The request is for money for extra ties, fence posts, stone and labour. The letter is slightly singed at the bottom. This does not affect the text, Jan. 3, 1856.