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We encountered a patient with heavy Hymenolepis nana infection. The patient was a 44-year-old Korean man who had suffered from chronic hepatitis (type B) for 15 years. A large number of H. nana adult worms were found during colonoscopy that was performed as a part of routine health screening. The parasites were scattered throughout the colon, as well as in the terminal ileum, although the patient was immunocompetent. Based on this study, colonoscopy may be helpful for diagnosis of asymptomatic H. nana infections.  相似文献   
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CMP-N-acetylneuraminic acid: glycoprotein sialyltransferase activities were assayed in microsomal fractions from chicken liver and hepatoma, induced by the leukosis virus strain Mc-29, using asialofetuin as the substrate acceptor of N-acetylneuraminic acid. The effect of some nucleotides and metal ions on the enzyme activity was investigated. Kinetic studies revealed that the Km values toward asialofetuin at a saturation concentrations of CMP-N-acetylneuraminic acid for both liver and hepatoma enzymes are very closed, while V value was lower for the tumor enzyme. The liver and hepatoma enzymes have no exogenous Mn cations requirement and are inhibited by CTP, CMP and ATP. CMP was shown to act as a competitive inhibitor with an apparent Ki of 0.24 mM for the liver and 0.16 mM for hepatoma enzyme, respectively.  相似文献   
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Exopolysaccharide production in Rhizobium and its role in invasion   总被引:13,自引:3,他引:10  
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Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disorder characterised by tumours of the parathyroids, pancreas and anterior pituitary. The MEN1 gene has been localised to a 2-Mb region of chromosome 11q13 by meiotic mapping studies in MEN1 families. Such studies may have a limited resolution of approximately 1 cM (i.e. 1 Mb) and we have therefore investigated 96 MEN1 families (40 British, 17 French, 12 Finnish, 7 Swedish, 7 Dutch, 7 North American, 2 Australian, 1 New Zealand, 1 German, 1 Spanish and 1 Danish) for linkage disequilibrium, in order to facilitate a finer mapping resolution. We have utilised five microsatellite DNA sequence polymorphisms from the candidate region and have accurately determined their allele sizes, which ranged from 161 bp to 272 bp. The heterozygosity and number of alleles (given in brackets), respectively, at the loci were: D11S1883 (76%, 11), D11S457 (55%, 5), PYGM (94%, 18), D11S1783 (10%, 4) and D11S449 (87%, 16). Allelic association was assessed by Chi-square 2 ×n contingency tables, by Fisher exact 2 ×n contingency tables and by a likelihood-based approach. The results of haplotype analysis revealed 91 different affected haplotypes in the 96 families, an identical affected haplotype being observed in no more than two families. These results indicate the absence of an ancestral affected haplotype. Significant linkage disequilibrium (P < 0.005) could be established amongst the microsatellite loci but not between the loci and MEN1 in either the total population or in any of the geographical sub-populations. The absence of linkage disequilibrium between MEN1 and the polymorphic loci is probably the result of the occurrence of multiple different disease-causing mutations in MEN1. Received: 1 April 1997 / Accepted: 25 June 1997  相似文献   
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