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Eledoisin and ceruletide, two nonmammalian hormonelike peptides, have been explored for possible pharmaceutical application. At present, only a few of the potentialities of the two drugs have been exploited. Eledoisin is used in ophthalmology as a lachrymal secretagogue; ceruletide is applied in the radiological diagnosis of gallbladder, biliary system, and digestive tract disorders, in the study of exocrine pancreatic function, and in the treatment of postoperative paralytic ileus and intestinal hypotony and atony. Possible analgesic and antipsychotic applications of ceruletide are under study. Developments of synthetic and analytical methods for both peptides are briefly reviewed. Technical devices or alternative routes of administration are envisaged in order to enlarge both the present market and the field of application.  相似文献   
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Summary In this paper we show how an Artificial Immune System can be used to study pattern recognition processes and learning. In particular we show the ability of the model to discover and maintain coverage of the diverse patterns through mechanism of evolution and mutation.  相似文献   
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We performed ultra-deep methylation analysis at single molecule level of the promoter region of developmentally regulated D-Aspartate oxidase (Ddo), as a model gene, during brain development and embryonic stem cell neural differentiation. Single molecule methylation analysis enabled us to establish the effective epiallele composition within mixed or pure brain cell populations. In this framework, an epiallele is defined as a specific combination of methylated CpG within Ddo locus and can represent the epigenetic haplotype revealing a cell-to-cell methylation heterogeneity. Using this approach, we found a high degree of polymorphism of methylated alleles (epipolymorphism) evolving in a remarkably conserved fashion during brain development. The different sets of epialleles mark stage, brain areas, and cell type and unravel the possible role of specific CpGs in favoring or inhibiting local methylation. Undifferentiated embryonic stem cells showed non-organized distribution of epialleles that apparently originated by stochastic methylation events on individual CpGs. Upon neural differentiation, despite detecting no changes in average methylation, we observed that the epiallele distribution was profoundly different, gradually shifting toward organized patterns specific to the glial or neuronal cell types. Our findings provide a deep view of gene methylation heterogeneity in brain cell populations promising to furnish innovative ways to unravel mechanisms underlying methylation patterns generation and alteration in brain diseases.  相似文献   
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Pairwise linkage analyses are reported between the locus for multiple endocrine neoplasia type 2A (MEN-2A) and 20 restriction fragment length polymorphisms (RFLPs) in a single large kindred which was previously screened for linkage with this form of cancer using 23 blood group and serum protein polymorphisms. No significant, positive lod scores have been obtained so far. These 20 RFLPs have excluded the MEN2 locus from about as much of the genome as did the 23 classical markers previously reported. This is a clear demonstration of the value of RFLPs for linkage studies since these 20 RFLPs were not selected for being the most polymorphic of those available. Over 10% of the human genome has been excluded from linkage with the MEN2 locus in this particular family.  相似文献   
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