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H Ota T Katsuyama S Nakajima H El-Zimaity JG Kim DY Graham RM Genta 《Canadian Metallurgical Quarterly》1998,29(8):846-850
Helicobacter pylori seem to avoid areas of intestinal metaplasia in the gastric mucosa, but attachment of these bacteria to epithelium with the appearance of incomplete intestinal metaplasia has been documented. To characterize the nature of the epithelium to which H pylori was attached, we carried out an immunohistochemical study using monoclonal antibodies against gastric surface mucous cell mucins (M1), blood group-related carbohydrates antigens (Le(a), sialyl Le(a), Le(b), type 1H, and type 2H) and sialyl Tn antigen. The results of this study suggest that these areas of H pylori attachment represent a hybrid epithelium whose cells share characteristics of both gastric surface mucous cells and intestinal metaplastic cells. Whether all areas of incomplete intestinal metaplasia represent an intermediate stage between the normal gastric epithelium and the fully developed complete type of metaplasia remains to be determined. 相似文献
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Graham A. Jullien Wenzhe Luo Neil M. Wigley 《The Journal of VLSI Signal Processing》1996,14(2):207-220
This paper discusses strategies for implementing DSP systems using residue replication. The theory, recently introduced by two of the authors, uses formal polynomial ring mappings, from binary representations, to direct product ring implementation of integer processing arrays. The mapping produces completely independent computational arrays each computing over the same ring. This paper describes an architecture and processing array to implement, and take advantage of, the special computational ring structures that result from the mapping. A brief review of the theory and mapping techniques, is followed by the discussion of the architecture and VLSI design of an efficient inner product processing array using Fermat Primes. 相似文献
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One hundred and twenty-four patients over the age of 75 years were assessed for the cause of their macrocytosis (MCV > 95 fl). A definitive diagnosis was reached in 75/124 (60%) by non-invasive techniques. The remainder underwent a bone marrow biopsy yielding a definitive diagnosis in a further six patients who had an identifiable myelodysplastic syndrome (MDS). A high proportion of the remainder had morphological abnormalities which fitted with no recognized pathological entity. It is suggested that these may represent MDS in evolution. 相似文献
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Peter Eaton Andrea Ragusa Caroline Clavel Cristina T Rojas Paul Graham Raúl V Durán Soledad Penadés 《IEEE transactions on nanobioscience》2007,6(4):309-318
Glyconanoparticles which present carbohydrate and amino groups motifs at their surface were produced. These particles were highly stable and soluble in aqueous solutions. The presence of the carbohydrate groups also allowed the inclusion of more strongly binding groups, without affecting solubility. The binding of a model DNA, plasmid by these nanoparticles was studied by atomic force microscopy, transmission electron microscopy, and gel electrophoresis. Significant differences between the nanoparticles based on their affinities for the DNA were found, with implications for their potential use as nonviral gene delivery agents. 相似文献
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This paper reports a method to produce networks of crystalline gallium oxide comprised of one‐dimensional (1D) nanostructures. Because of the unique arrangement of wires, these crystalline networks are termed as ‘nanowebs’. Nanowebs are of great technological interest since they contain wire densities of the order of 109 cm–2. A possible mechanism for the fast self‐assembly of crystalline metal oxide nanowires involves multiple nucleation and coalescence via oxidation–reduction reactions at the molecular level. The preferential growth of nanowires parallel to the substrate enabled them to coalesce into regular polygonal networks. The individual segments of the polygonal network consist of both nanowires and nanotubules of β‐gallium oxide. Individual wire properties contribute to a nanoweb’s overall capacity and the implications for devices based on nanowebs are expected to be enormous. 相似文献