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961.
An 11-year-old boy with laryngeal carcinoma underwent a partial laryngectomy. Subsequently, a cervical metastatic node developed eight months following a tonsillectomy; a radical neck dissection was performed. The patient has remained free of disease over a ten-year follow-up period. In our review of the English literature, no similar case report was found. The potential relationship of tonsillectomy to alterations in local T cell-mediated immune response is discussed. 相似文献
962.
S Sridaromont RH Feldt DG Ritter GD Davis JE Edwards 《Canadian Metallurgical Quarterly》1976,38(1):85-94
An obsessive-compulsive patient was treated with modified analytic therapy to enable him to complete his first college year. As an assistant professor, he returned 19 years later complaining of retarded ejaculation. Traditional psychotherapy (52 sessions) failed to resolve the problem. After eight sessions of solo sex therapy, the ejaculatory dysfunction was mastered. 相似文献
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964.
Proposals have recently been made within the computer industry to standardize local area computer networking hardware and, although such standards are primarily aimed at the office automation market, they will undoubtedly find many applications in distributed industrial control where a requirement for high speed reliable standardized digital communications also exists. A simple manufacturing cell will be described which demonstrates the advantage of distributed control by using an integrated communications network employing low cost twin axial cable. The individual cell element control systems are supervised by a single computer station providing both control and management information. It will also be shown how such techniques can be applied within industrial manufacturing systems by considering the use of computer networks within a process plant and for the integration of industrial robot systems. 相似文献
965.
Pericardial tamponade in a 51-year-old man after acute anteroseptal myocardial infarction was the result of spontaneous perforation of an atheromatous coronary artery. The value of a simple necropsy technique of selective coronary arteriography in demonstrating the lesion is described. 相似文献
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969.
The attachment of virulent strains of Agrobacterium tumefaciens to plant cells is the first step in the bacterial induction of tumors. Binding of A. tumefaciens to carrot tissue culture cells occurred as a two-step process. The initial step was the attachment of the bacteria to the plant cell wall. Living plant cells were not required. Bacterial attachment to heat-killed or glutaraldehyde-fixed carrot cells proceeded with only slightly altered kinetics and unaltered bacterial strain specificity. After the bacteria bound to the carrot cell surface, scanning electron microscopy showed that fibrils developed, surrounded the bacteria, and anchored them to the plant cell surface. These fibrils were synthesized by the bacteria and not by the plant cell since they were also made after the attachment of A. tumefaciens to dead carrot cells and since under some conditions the bacteria synthesized fibrils in the absence of plant cells. Calcofluor staining, acid hydrolysis, enzymatic digestion studies, and infrared spectroscopy showed that the fibrils were composed of cellulose. The formation of these cellulose fibrils occurred during the attachment of virulent strains of A. tumefaciens to plant cells in vitro. The fibrils anchored the bacteria to the plant cell surface and entrapped additional bacteria. The multiplication of entrapped and attached bacteria resulted in the formation of large clusters of bacteria held close to the plant cell wall and plasma membrane by cellulose fibrils. This high concentration of bacteria may facilitate transfer of Ti plasmid deoxyribonucleic acid to the plant cell resulting in the formation of tumors. 相似文献
970.
Spin‐coated epoxy resin embedding technique enables facile SEM/FIB thickness determination of porous metal oxide ultra‐thin films
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A facile nonsubjective method was designed to measure porous nonconductive iron oxide film thickness using a combination of a focused ion beam (FIB) and scanning electron microscopy. Iron oxide films are inherently nonconductive and porous, therefore the objective of this investigation was to optimize a methodology that would increase the conductivity of the film to facilitate high resolution imaging with a scanning electron microscopy and to preserve the porous nature of the film that could potentially be damaged by the energy of the FIB. Sputter coating the sample with a thin layer of iridium before creating the cross section with the FIB decreased sample charging and drifting, but differentiating the iron layer from the iridium coating with backscattered electron imaging was not definitive, making accurate assumptions of the delineation between the two metals difficult. Moreover, the porous nature of the film was lost due to beam damage following the FIB process. A thin layer plastication technique was therefore used to embed the porous film in epoxy resin that would provide support for the film during the FIB process. However, the thickness of the resin created using conventional thin layer plastication processing varied across the sample, making the measuring process only possible in areas where the resin layer was at its thinnest. Such variation required navigating the area for ideal milling areas, which increased the subjectivity of the process. We present a method to create uniform thin resin layers, of controlled thickness, that are ideal for quantifying the thickness of porous nonconductive films with FIB/scanning electron microscopy. 相似文献