摘要:

Abstract.Mucosa from the anterior palate of the rat was fixed in a variety of commonly used fixatives for electron microscopy having different osmolalities and chemical compositions. The volume of the intercellular space of the epithelium was assessed using a stereological technique in which a test grid was superimposed over electron micrographs of sections through the epithelium, and the relative areas of that test grid overlying cellular and intercellular components were measured. Epithelium fixed in solutions isotonic with mammalian serum showed an intercellular space occupying approximately 4% of the total tissue volume. There was a tendency for the intercellular space to increase with increasing osmolality of the fixative, although this relationship was not a simple one; the chemical nature of the fixative solution may also influence the response.

ISSN:0904-2512    

DOI:10.1111/j.1600-0714.1973.tb01676.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY

摘要:

Abstract.The effects on normal and mildly burnt oral epithelium of rat palate of commonly used fixatives differing in osmolality and composition were examined quantitatively by the application of a stereological method at the electron microscope level. With five out of six different fixative solutions the intercellular spaces of the burnt epithelium occupied a significantly larger relative volume than in normal epithelium, and the tissue did not respond in the same way as normal epithelium does to differences in fixative solution. This may reflect changes in tissue properties resulting from burning. The differences in size of intercellular spaces between tissues fixed in different solutions were such that burnt tissue fixed in one solution did not always show larger intercellular spaces than normal tissue fixed in another solution. Observations of the ultrastructural changes of inflammation in oral epithelium should therefore always he checked by observations on identically fixed normal tissue.

ISSN:0904-2512    

DOI:10.1111/j.1600-0714.1973.tb01677.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY

摘要:

Abstract.Images were obtained from intact and acid etched enamel surfaces (both before and alter growth of surface apatite) with electron diffraction, transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Labial surfaces (intact) of bovine incisor teeth were slightly abraded and pumiced. They were then etched by a 14‐hour immersion in 2mM sodium acetate‐acetic acid buffer at pH 5.0; an average of 31 μ.Mol/cm2calcium and 24 μMol/cm2phosphate was dissolved from the surfaces. The SEM. and TEM showed loss of minerals to a depth of 10 μm. Dissolution was largely in central areas of enamel prisms, and prismatic structure in the etched surfaces was retained. Electron diffraction, SEM, and TEM showed the growth of crystalline apatites at the etched surfaces after 24 to 96 hours immersion in neutral pH solution (metastable) which contained 1.5 mM Ca+2, 0.9 mM H2PO4/HPO4−2, 0.05 mM F−, and 150 mM NaCl. Indirect analysis, at the loss of calcium and phosphate concentrations in the metastable solution after immersion periods, indicated deposition of approximately 24μMol/Cm2calcium and 14μMol/cm2phosphate on the etched surfaces. Results show induction of apatite crystal growth and recrystallization at enamel surfaces in otherwise stable solutions containin

ISSN:0904-2512    

DOI:10.1111/j.1600-0714.1973.tb01678.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY

摘要:

Abstract.The light and electron microscopic appearances of an atypical calcifying odontogenic mandibular tumor containing “amyloid” arc presented. In a part of the tumor, PAS‐reactive hyalin eosinophilic material which showed green dichroism by polarized light after Congo Red staining, and also hematoxylinophilic mineralized portions were found. By electron microscopy the hyalin material revealed a fibrillar structure. The fibrils had a median diameter of 100 Å. and were short and curved with some apparent outer modularity. They differed morphologically from other unidentified extracellular and intracellular densely packed fibrils of about 85 Å in diameter, from collagen fibers and from a small number of elastic fibers found in the connective tissue. Apparent calcification had occurred in aggregates of the 100 Å fibrils to produce‐ a linear and angulated electron‐dense front. Calcification within epithelial cells of the tumor, and calcification in irregular foci around collagen fibers were also found.Quite different histopathological appearances were noted by light microscopy in different parts of the tumor. An anterior region contained numerous islands with large areas of odontogenic epithelium with peripheral ameloblast‐like cells and also solid sheets of cuboidal epithelial cells resembling in some ways those of the calcifying epithelial odontogenic tumor.The upper or posterior region of the tumor contained marked cavernous hemangiomatous elements separated by a loose and often myxoid stroma. Metaplastic cartilage formation had occurred in one part of it. The third molar tooth was located near the coronoid notch. The tumor, although not precisely classified, appeared to be an atypical ameloblastic

ISSN:0904-2512    

DOI:10.1111/j.1600-0714.1973.tb01679.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY

摘要:

Abstract.By indirect immunofluorescence, 13 different proteins were studied in 2‐hour, acquired pellicles collected from four subjects over a 5‐day period. The 300 specimens were coded, and the intensity of fluorescence specific for each protein was scored by two independent observers.Statistical analyses indicated that the mean score values differed significantly when a comparison was made between individual proteins or between subject‐donors of the pellicles. Also, the scores for each protein were highly dependent on the subject. Despite daily fluctuations, the pellicles from each subject presented a characteristic protein profile.Frequently, high fluorescence scores were noted for proteins of generally low salivary concentration, e.g., IgM and IgG. The third component of complement was discovered in several pellicles and, by subsequent testing, in whole saliva but not in parotid fluid. Its presence in pellicles of an edentulous subject suggests that this protein may be transferred across the oral epith

ISSN:0904-2512    

DOI:10.1111/j.1600-0714.1973.tb01680.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY

ISSN:0904-2512    

DOI:10.1111/j.1600-0714.1973.tb01681.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY