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101.
We have recently reported that thymic B lymphocytes (TBL) are the first B-cell subpopulation undergoing isotype switching to IgG and IgA during embryonic life. The aim of this study is to analyze the influence of antigenic stimulation on TBL location and activity using a germ-free (GF) newborn pig model, in which maternal antibodies and antigens do not affect B-cell development. Immunohistological analysis showed that TBL were disseminated mainly in the thymic medulla. There were no differences in the distribution of TBL, both in GF newborn piglets before and after colonization with Escherichia coli and in older conventionally reared (CONV) piglets. The number of immunoglobulin (Ig)-secreting cells measured by the ELISPOT method was not influenced by microflora and food antigens. IgM-positive cells secreting IgM and CD45RC-positive cells spontaneously producing IgM, IgG, and IgA were detected in newborn thymus. Our findings suggest that TBL differentiation and Ig switching to IgG and IgA-secreting cells is not influenced by external antigens and that the thymic microenvironment plays an important role in this process.  相似文献   
102.
A design-for-test methodology for SC filters is presented, based on an architecture using some additional circuitry and providing extra capabilities for both off- and on-line tests. The approach uses a comparison (voting) mechanism to indicate whether or not two copies of a filter element (a biquad, for instance) have a similar response during their actual operation. The design and implementation of a few filter examples are included to assess the potential usefulness of this new approach.  相似文献   
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It is shown that the Caenorhabditis elegans genome contains several distantly related members of the gene family of saposin-like proteins. The putative products of genes T07C4.4, T08A9.7A, T08A9.7B, T08A9.8, T08A9.9, T08A9.10 are similar to the amoebapores of Entamoeba histolytica, granulysin of cytotoxic T lymphocytes and a putative amoebapore-related protein of the liver fluke Fasciola hepatica inasmuch as they consist of only a single saposin-like domain and a secretory signal peptide. The saposin-like domain of protein T07C4.4, which is most closely related to NK-lysin and granulysin, has been expressed in Escherichia coli and the recombinant protein was shown to have a circular dichroism spectrum consistent with the helix bundle structure characteristic of saposin-like domains. Recombinant T07C4.4 protein was found to have antibacterial activity, suggesting that these amoebapore homologs may play a role in antibacterial mechanisms of C. elegans.  相似文献   
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Artificial Intelligence Review - Attribute weighting is a task of paramount relevance in multi-attribute decision-making (MADM). Over the years, different approaches have been developed to face...  相似文献   
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Distributed and Parallel Databases - Given two datasets of points (called Query and Training), the Group (K) Nearest-Neighbor (GKNN) query retrieves (K) points of the Training with the smallest sum...  相似文献   
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Software Quality Journal - Energy consumption of software has been becoming increasingly significant, since it can vary according to how the software has been developed. In recent years, developers...  相似文献   
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We generalise belief functions to many-valued events which are represented by elements of Lindenbaum algebra of infinite-valued ?ukasiewicz propositional logic. Our approach is based on mass assignments used in the Dempster–Shafer theory of evidence. A generalised belief function is totally monotone and it has Choquet integral representation with respect to a unique belief measure on Boolean events.  相似文献   
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