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M R Chevallier 《Molecular and cellular biology》1982,2(8):977-984
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Polymerase chain reaction assay specific for pathogenic Leptospira based on the gene hap1 encoding the hemolysis-associated protein-1 总被引:1,自引:0,他引:1
Branger C Blanchard B Fillonneau C Suard I Aviat F Chevallier B André-Fontaine G 《FEMS microbiology letters》2005,243(2):437-445
In this study, we used Southern hybridization of genomic DNA with the integral hap1 gene as a probe to show that this gene is only present in pathogenic Leptospira strains. We then selected PCR primers based on the hap1 gene, and tested them on several Leptospira strains and biological samples. Specific amplification was obtained for all pathogenic strains tested. Negative PCR results were observed with all saprophytic leptospire strains used as well as with other spirochetes and bacteria commonly found in biological samples. The results of direct PCR performed on biological samples, such as blood, urine or kidneys correlated with the results obtained with the classical Leptospira tests (culture and MAT). A PCR assay based on this gene would be a very useful tool for the rapid, sensitive and specific identification of pathogenic leptospires in samples for diagnosis or epidemiological survey. 相似文献
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EFFECTS OF HUMAN ACTIVITIES ON STRUCTURE AND COMPOSITION OF WOODY SPECIES OF THE NOKREK BIOSPHERE RESERVE OF MEGHALAYA,NORTHEAST INDIA 下载免费PDF全文
Aims Our study was conducted in the Nokrek Biosphere Reserve (NBR) in the Garo hills districts of Meghalaya, Northeast India. Our aim was to assess the effects of human activities on plant diversity,population structure and regeneration.Methods We selected a representative 1.2 hm2 stand in both the core and buffer zones of NBR. Structure and composition were determined by randomly sampling square quadrats, population structure was assessed by determining age structure, and regeneration was assessed by measuring densities of seedling, sapling and adult trees.Important findings More woody species were recorded from the core zone than the buffer zone (87 vs. 81 species), and there were a large number of tropical, temperate, and Sino-Himalayan, Burma-Malaysian and Malayan elements, primitive families and primitive genera. The trees were distributed in three distinct strata,canopy, subcanopy and sapling. Subcanopy and sapling layers had the highest species richness (81% -88% ). Lauraceae and Euphorbiaceae were the dominant families in terms of the number of species, and a large number of families were represented by single species. Most woody species (57 % - 79 % ) were contagiously distributed and had low frequency ( < 20% ). Although stand density was high in the buffer zone, its basal area was low compared to the stand in the core zone. Low similarity and high β-diversity indicate marked differences in species composition of the stands. Shannon diversity index was high in both the stands, while Simpson dominance index was low. The diameter-class distribution for dominant species revealed that the most had a large number of young individuals in their populations. Preponderance of tree seedlings, followed by a steep decline in population density of saplings and adult trees, indicated that the seedling to sapling stage was the most critical in the life cycle of the tree populations. Most species (42 % - 48 % ) had no regeneration,25 % - 35 % had good/fair regeneration, and the rest had poor regeneration or reoccurred as immigrants. 相似文献
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T. Belleville S. Bouhadiba E. Pautas S. Chevallier I. Peyron I. Gouin V. Siguret 《Bio Tribune Magazine》2010,35(1):10-14
Elderly patients are commonly frail, due to a lot of comorbid conditions and numerous medications. These patients are at high risk of bleeding when treated with vitamin K antagonist (VKA). Special considerations on the choice of VKA drug, dosing and monitoring have to be taken into account in the elderly in order to avoid over-anticoagulation and to minimize the haemorrhagic risk which consequences may be dramatic or fatal in this age group. In these patients, INR monitoring is crucial, especially at the start of treatment. The use of dosing algorithms specifically developed for elderly patients allows to decrease over-anticoagulation during the initiation period. INR has to be monitored more frequently in case of acute illness or in case of modification of the associated drugs. Patient education is of great importance, even in geriatric patients and has been shown to improve the quality of anticoagulation. New oral anticoagulants with a wider therapeutic index seem to be of great interest. 相似文献
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Nicolas Baumard Coralie Chevallier 《Proceedings. Biological sciences / The Royal Society》2015,282(1818)
In contrast with tribal and archaic religions, world religions are characterized by a unique emphasis on extended prosociality, restricted sociosexuality, delayed gratification and the belief that these specific behaviours are sanctioned by some kind of supernatural justice. Here, we draw on recent advances in life history theory to explain this pattern of seemingly unrelated features. Life history theory examines how organisms adaptively allocate resources in the face of trade-offs between different life-goals (e.g. growth versus reproduction, exploitation versus exploration). In particular, recent studies have shown that individuals, including humans, adjust their life strategy to the environment through phenotypic plasticity: in a harsh environment, organisms tend to adopt a ‘fast'' strategy, pursuing smaller but more certain benefits, while in more affluent environments, organisms tend to develop a ‘slow'' strategy, aiming for larger but less certain benefits. Reviewing a range of recent research, we show that world religions are associated with a form of ‘slow'' strategy. This framework explains both the promotion of ‘slow'' behaviours such as altruism, self-regulation and monogamy in modern world religions, and the condemnation of ‘fast'' behaviours such as selfishness, conspicuous sexuality and materialism. This ecological approach also explains the diffusion pattern of world religions: why they emerged late in human history (500–300 BCE), why they are currently in decline in the most affluent societies and why they persist in some places despite this overall decline. 相似文献
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Abstract Competition experiments revealed that adenine and guanine were transported by a purine permease in both Candida glabrata 4 and a C. glabrata 4 cytosine permease negative mutant. The C. glabrata 4 cytosine permease negative mutant was isolated using 5-fluorocytosine selection. This mutant no longer transported cytosine, but transported adenine and guanine. A transport system for hypoxanthine was not detected. Hence, in addition to the cytosine permease, a purine permease exists in C. glabrata . This differs from the purine cytosine permeases in Saccharomyces cereuisiae and Candida albicans which transport adenine, cytosine, guanine and hypoxanthine. 相似文献
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