Life Sciences Commons^™

Intrauterine Device (Iud) Associated Pathology: A Review Of Pathogenic Mechanisms, Waldemar A. Schmidt, Karmen L. Schmidt

Scanning Electron Microscopy

This paper summarizes our studies of IUD-related disease with those previously published by others. Our data are based upon 51 IUDs and 42 index cases of IUD-related disease demonstrating specific processes. Gross, dissecting microscope, scanning electron microscope and X-ray microanalysis examinations were made of selected IUDs and associated tissues. Tissue associated with the IUDs revealed inflammation in 59.4%, calcific material in 6.3% and no abnormality in 34.4%. JUD-associated tissue responses were accompanied by changes of the IUD; these changes involved deposition of substances upon the IUD surface and degradation of the JUD itself. Disintegration of the IUD, its string or …

Scanning And Transmission Electron Microscopic Study Of Recovered Porcine Aortic Valved Conduits, D. J. Allen, I. H. Fentie, J. T. Davis, Angela Lineen

Scanning Electron Microscopy

Four explanted porcine aortic valved conduits were examined using scanning and transmission electron microscopy. Sources of obstruction such as neointima or "peel" and calcification were observed. In one sample the neointima was found to possess an unusually large expanse of squamous cells partially lining the luminal surface. This lining much resembled a normal endothelium, which is not an expected feature of neointima. Cells, presumably of host origin, were noted upon the leaflet surfaces. They did not seem as well organized as those found on the neointima. Calcification did not seem greatly advanced but was clearly apparent. Certain treatments proposed by …

Transmission Electron Microscopy Of Semiconductor Materials And Devices, R. B. Marcus

Scanning Electron Microscopy

This paper surveys the application of transmission electron microscopy (TEM) to semiconductor materials and device technology. A broad spectrum of TEM studies requires the preparation of either plan-view or vertical sections; these sections are made using mechanical abrasion, chemical etching or ion milling or a combination of these procedures. A survey is then given of applications of TEM to four classes of studies of semiconductor materials and devices: the configuration of device features, crystallographic defects, lattice and atomic resolution imaging, and the analysis of phase and chemical composition.

Delineation Of Emitter-Collector Shorts In Bipolar Test Structures By Voltage Contrast Scanning Electron Microscopy, A. H. Carim, R. Sinclair, W. T. Stacy

Scanning Electron Microscopy

In examining emitter-collector shorts and their relationship to structural defects, we desire a nondestructive method for locating the short-circuited devices in large test arrays. Voltage contrast scanning electron microscopy (VC-SEM) and an established electrochemical anodization technique have been used to identify electrically faulty bipolar transistors. Direct comparison of these approaches was achieved by examining the same emitters with each method. The results indicate that VC-SEM may serve as a useful technique for delineating E-C shorts because of its nondestructive and purely electrical nature. In our qualitative investigation, the sensitivity and voltage resolution available by VC-SEM were not sufficient to differentiate …

The Application Of Physico-Chemical Procedures In The Analysis Of Urinary Calculi, Allen L. Rodgers

Scanning Electron Microscopy

All physico-chemical techniques used in the analysis of urinary calculi have inherent advantages and limitations. Al though x-ray powder diffraction can identify constituents unambiguously, certain minor components can be missed. Infrared spectroscopy is more sensitive but band assignment at low concentrations is difficult. Scanning electron microscopy together with energy dispersive x-ray analysis permits the simultaneous investigation of morphology and chemical microstructure. However, microanalysis of elements lighter than sodium is not possible and constituents are prone to irradiation damage. With the electron microprobe, minor constituents can be detected but tedious sample preparation procedures are required. Transmission electron microscopy is extremely useful …

Ultrastructural Studies Of Crystal-Organic Matrix Relations In Renal Stones, P. -T. Cheng, A. D. Reid, K. P. H. Pritzker

Scanning Electron Microscopy

Biochemically the organic matrix of kidney stones contains mucoproteins, mucopolysaccharides, inorganic material and bound water. Morphologically, the organic matrix exists as either amorphous or fibrous forms. We have attempted to critically evaluate results from analytical and morphological studies on stone matrices using light microscopy, histochemistry, x-ray diffraction, scanning electron microscopy, x-ray energy dispersive spectrometry, transmission electron microscopy and selected area electron diffraction.

On the surface of calcium oxalate stones, there are usually large masses of randomly deposited calcium oxalate crystals each coated with organic matrix. Transmission electron microscopy shows these large surface crystals are composed of rows of smaller crystallites …

Immunocytochemical Labeling Of Enzymes In Low Temperature Embedded Plant Tissue: The Precursor Of Glyoxysomal Malate Dehydrogenase Is Located In The Cytosol Of Watermelon Cotyledon Cells, C. Sautter

Scanning Electron Microscopy

The Lowicryl-technique in combination with protein A gold was used in order to localize the precursor of glyoxysomal malate dehydrogenase in watermelon cotyledons. Preservation of the antigen was evaluated by a preembedding technique in isolated organelles. The glyoxysomal malate dehydrogenase was localized in tissue sections by a postembedding technique. Antigens of glyoxysomal malate dehydrogenase were found in the glyoxysomal matrix and in the cytosol, whereas the endoplasmic reticulum was completely free of labeling. Controls are presented by preimmunserum, by a serum against various proteins of the glyoxysomal membrane and by application of cycloheximide in order to inhibit translation at cytosolic …

Use Of Scanning Electron Microscopy To Study Structural-Functional Relationships In Normal And Diseased Platelets, J. C. Mattson

Scanning Electron Microscopy

This paper reviews the contribution of scanning electron microscopy (SEM) to our understanding of platelet physiology and pathology. Observations of platelet shape changes which accompany activation and the ability to visualize and analyze platelet aggregation and adhesion in three dimensions make this experimental medium an important tool in the evaluation of healthy and diseased platelets. While SEM adds a valuable third dimension to the study of morphology and ultrastructure, its greatest contribution is realized when studies are correlated directly with light and/or transmission electron microscopic observations and with studies of functional capacity.

Energy Selecting Electron Microscopy, F. P. Ottensmeyer

Scanning Electron Microscopy

One of the major improvements in transmission electron microscopy over the last years is the addition of the capability of producing images with electrons that have specific narrow energy bands out of the total spectrum of energies they possess after having passed through the specimen. Though the idea is not new, the power of this application is only beginning to be recognized. Most simply, selection of elastically scattered electrons permits increased contrast in high resolution i mages in bright field, dark field, and diffraction. The use of combined elastic and inelastic signals adds entirely new contrast mechanisms, partially independent of …