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Genetic diversity was characterized in 20 isolates of Grapevine fanleaf virus (GFLV) recovered from naturally infected grapevine plants (Vitis vinifera) in the North of Tunisia. Viral RNAs were isolated by oligoprobe capture, and a 605 bp fragment containing a part of the viral coat protein gene was amplified by RT-PCR. Sequence variation among isolates was characterized by restriction fragment length polymorphism (RFLP) analysis and confirmed by sequencing. The GFLV infections are found as a complex mixture of closely related genomes. In further studies, RFLP analyses of virus isolates using AluI showed that GFLV populations in Tunisian vineyards consist of two restrictotypes corresponding to distinct sub-populations Sp1 and Sp2. The relative field distribution of these sub-populations showed that Sp2 was more abundant. Individual genomes were recovered by cloning the RT-PCR products. The sequences were found to vary from each other by as much as 11%. Cloning from mixed infections showed that Sp2 are also predominant.  相似文献   
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International Urology and Nephrology - Biomarkers for the diagnosis and monitoring treatment response of kidney cancer are urgently needed. Neutrophil gelatinase-associated lipocalin (NGAL) is a...  相似文献   
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Diabetes mellitus is the most common chronic metabolic disease. The raising diabetes epidemic is unfolding as an interaction between several environmental factors and a genetic predisposition. The aim of the current study was to evaluate the role of the PPARγ-Pro12Ala and ENPP1-K121Q polymorphisms on type 2 diabetes (T2D) risk in a case–control study in the Tunisian population. To assess for any association of ENPP1-K121Q and PPARγ-Pro12Ala polymorphisms with T2D risk, we analysed the genotypic and allelic distributions of each variant in the studied cohort. Our results support that the genetic variation at ENPP1-K121Q predisposes to T2D in the Tunisian population after adjustment on gender, age and BMI status (OR = 1.55, 95%CI [1.11–2.16], p = 0.007).Conversely, the PPARγ-Pro12Ala variant seems not to have a significant effect on T2D risk in our Tunisian cohort. However, the minor A-allele would convey protection against overweight in the Tunisian population. In fact, the over weighted subjects showed a significantly lower frequency of A-allele than lean controls (OR = 0.49, 95%CI [0.25–0.97], p = 0.02). In conclusion, our findings support the hypothesis that ENPP1-121Q is involved in the genetic susceptibility of T2D in the Tunisian population, while the PPARγ-12Ala allele may confer protection against overweight.  相似文献   
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This work is devoted to the synthesis and study of the different properties of ZnO nanoparticles (NPs) doped with the Ni element. We have used a simple co-precipitation technique for the synthesis of our samples and various structural, morphological and optical techniques for their analysis. Energy-Dispersive X-ray spectroscopy (EDX) confirms the stoichiometry of the samples. The X-Ray Diffraction (XRD) patterns reveal the hexagonal wurtzite phase of polycrystalline ZnO with a P63mc space group. Debye Scherrer and Williamson–Hall methods show that the average size of crystallites is around 40 nm. Transmission electron microscopy (TEM) images confirm the XRD results. The optical spectrum of Zn0.95Ni0.5O shows the presence of near-band-edge (NBE) ultraviolet emission. The absorption defect bands appearing near the blue–green region and near infrared emission are attributed to the Ni2+ intra-3d luminescence. The electronic structure of the Ni2+ doped ZnO NPs confirms the Td site symmetry of Ni2+ in the ZnO host crystal and leads to a perfect correlation between calculated and experimental energy levels.

This work is devoted to the synthesis and study of the different properties of ZnO nanoparticles (NPs) doped with the Ni element.  相似文献   
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