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1.
Summary Direct gene analysis of the haptoglobin gene region was carried out by Southern blotting using an Hp cDNA as probe. Two types of polymorphism were observed: one due to intragenic duplication, is characterized by a constant fragment length difference of 1700bp observed with several enzymes and by complete correspondence with the protein molecular weight polymorphism; the second type, due to point mutation, was represented by two additional restriction sites for Eco RI and Pst I, with a frequency comparable to that of other genes. These two mutations segregated together in families, suggesting that the recently described Hp related gene is closely linked to the Hp gene. Moreover, they were completely associated with each other. The evolutionary significance of this finding is discussed. 相似文献
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Chlorine dioxide disinfection temperature effects 总被引:1,自引:0,他引:1
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S Pampiglione M L Ricciardi S Visconti A Branca E Olivieri A Zamberletti 《Parassitologia》1987,29(1):1-13
A coprological survey was carried out in 1982-1983 in East Boè and in Canhabaque Island, (Bijagòs Islands), where 289 and 288 specimens of stools, respectively, have been collected. The samples were taken from apparently healthy subjects, of both sexes and of different age groups. The tests were made according to the modified Ritchie technique. The following results were obtained: A) East Boè: 1) Protozoa: E. coli 68.9%, E. nana 24.6%, G. intestinalis 8.7%, I. buetschlii 5.9%, E. histolytica 1.7%, E. hartmanni 0.7%, T. intestinalis 0.7%. b) Helminths: Ancylostomatidae 69.2%, T. trichiura 38.4%, S. stercoralis 6.2%, Taenia sp. 1.7%, H. nana 0.7%, S. haematobium 0.7%, S. mansoni 0.7%, S. fuelleborni 0.7%. B) Canhabaque: a) Protozoa: E. coli 85.1%, I. buetschlii 14.9%, E. nana 12.5%, G. intestinalis 8.3%, C. mesnili 7.3%, E. hartmanni 1.4%, E. histolytica 1.0%, T. intestinalis 0.4%. b) Helminths: Ancylostomatidae 87.9%, T. trichiura 9.4%, S. stercoralis 7.9%, S. fuelleborni 2.8%, Trichostrongylus sp. 1.4%, A. lumbricoides 0.7%, H. nana 0.4%. Eggs of Capillaria sp. probably pseudoparasites, were found in 8.7% of samples. The high prevalence of Ancylostomatidae infections appears to be related to the heavy fecal pollution all over the examined territory. The utilization of antihelminthic drug of popular medicine, which has a specific action on A. lumbricoides, could explain the lack and the low prevalence, respectively, of A. lumbricoides infections in both examined areas. In the past, other authors emphasized the low prevalence of this parasite for other Guinea Bissau regions which have a different geomorfological constitution. The cases of S. fuelleborni and H. nana are the first reported for Guinea Bissau. 相似文献
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Salvatore Oliviero Mario DeMarchi Angelo O. Carbonara Luigi F. Bernini Giuliano Bensi Giovanni Raugei 《Human genetics》1985,71(1):49-52
Summary The protein and gene structure of the Hp Johnson variant (Hp3) were analyzed in two related heterozygous individuals. The molecular weight (23kd) and amino acid composition of Hp3 alpha chain were in agreement with the triplicated structure first suggested by Smithies in 1964. Direct gene analysis by Southern blotting showed a three-fold tandem repeat of the same 1.7 kb DNA segment implicated in the Hp2 gene duplication. On the basis of these data a nine exon model for the Hp3 gene is proposed. 相似文献
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Inhibition of hepatic gluconeogenesis by the Rp-diastereomer of adenosine cyclic 3'',5''-phosphorothioate. 下载免费PDF全文
The specific intracellular cyclic AMP-dependent protein kinase antagonist, the Rp-diastereomer of adenosine cyclic 3',5'-phosphorothioate (Rp-cAMPS), inhibited both basal and cyclic AMP-agonist-induced rates of gluconeogenesis in hepatocytes isolated from fasted rats. Incubation of the cells in the presence of pyruvate and lactate and either the Sp-diastereomer of adenosine cyclic 3',5'-phosphorothioate (Sp-cAMPS) or glucagon produced a concentration-dependent increase in the rate of gluconeogenic glucose production which was shifted to higher concentrations of Sp-cAMPS or glucagon in the presence of Rp-cAMPS. Incubation of the cells with Rp-cAMPS in the absence of agonist produced no increase in the rate of glucose production and, in most cases, 100 microM-Rp-cAMPS resulted in 14-20% decrease in the substrate-stimulated rate of glucose production. Sp-cAMPS-induced gluconeogenesis was inhibited half-maximally at 1 microM-Rp-cAMPS and glucagon-induced gluconeogenesis was inhibited half-maximally at 12 microM-Rp-cAMPS. Approx. 10-15% of the inhibition of gluconeogenesis observed in the presence of Rp-cAMPS was due to conversion of glucose 6-phosphate to liver glycogen, consistent with Rp-cAMPS-induced reactivation of glycogen synthase. The remaining 85-90% inhibition of gluconeogenic glucose production resulted from the action of Rp-cAMPS on the cyclic AMP-sensitive enzymes controlling the rate of gluconeogenesis. 相似文献
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Melvin A. Benarde Bernard M. Israel Vincent P. Olivieri Marvin L. Granstrom 《Applied microbiology》1965,13(5):776-780
We found chlorine dioxide to be a more effective disinfectant than chlorine in sewage effluent at pH 8.5. Chlorine dioxide was also found to be a more stable bactericide in relation to pH in the range studied. 相似文献