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71.
In a context of changing carnivore populations worldwide, it is crucial to understand the consequences of these changes for prey populations. The recolonization by wolves of the French Vercors mountain range and the long-term monitoring (2001–2017) of roe deer in this area provided a unique opportunity to assess the effects of wolves on this prey. Roe deer was the main prey of wolves in the west Vercors mountain range during this recolonization. We compared roe deer abundance and fawn body mass in two contrasted areas of a wolf pack territory: a central area (core of the territory characterized by an intense use by wolves) and a peripheral area (used more occasionally). Roe deer population growth rates were lower in the central area between 2001 and 2006, resulting in a decline in roe deer abundance. Roe deer abundance substantially dropped in the two study areas after an extremely severe winter but the abundance of roe deer in the central area facing with wolves was slower to recover and remained at lower abundance levels for 6 years. Fawn body mass was consistently lower in the central area, varied similarly as roe deer abundance, and was not influenced by weather conditions or red deer population abundance. Altogether, the effects of wolves on roe deer in the central area occurred during a 10-year period following the establishment of wolves, through the interplay between wolf predation (before wolves started preying on red deer), harsh winter conditions and possibly naivety of prey to this recolonizing predator.  相似文献   
72.
Hydrodynamic limb vein injection is an in vivo locoregional gene delivery method. It consists of administrating a large volume of solution containing nucleic acid constructs in a limb with both blood inflow and outflow temporarily blocked using a tourniquet. The fast, high pressure delivery allows the musculature of the whole limb to be reached. The skeletal muscle is a tissue of choice for a variety of gene transfer applications, including gene therapy for Duchenne muscular dystrophy or other myopathies, as well as for the production of antibodies or other proteins with broad therapeutic effects. Hydrodynamic limb vein delivery has been evaluated with success in a large range of animal models. It has also proven to be safe and well‐tolerated in muscular dystrophy patients, thus supporting its translation to the clinic. However, some possible limitations may occur at different steps of the delivery process. Here, we have highlighted the interests, bottlenecks and potential improvements that could further optimize non‐viral gene transfer following hydrodynamic limb vein injection.  相似文献   
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The importance of Oreochromis in worldwide aquaculture and regional fisheries motivates the study of their genetic diversity in their native range. In this article, all mitochondrial cytochrome c oxidase subunit I gene (COI) sequences of Oreochromis species are retrieved from Barcode of Life Data system to quantify the available DNA barcoding information from wild individuals collected within the native ranges of the respective species. It is found that 70% of the known species in the genus still lack a COI barcode, and only 15% of the available sequences are from within the respective native ranges. Many of the available sequences have been produced from specimens acquired from aquaculture and introduced, naturalized populations, making the assessment of variation within the original native range challenging. Analyses of the wild-collected fraction of available sequences indicated the presence of cryptic lineages within Nile tilapia Oreochromis niloticus and O. schwebischi, the occurrence of potential introgressive hybridization between O. niloticus and blue tilapia O. aureus, and potential ancestral polymorphism between Karonga tilapia O. karongae and black tilapia O. placidus. This article also reports a case of misidentification of O. mweruensis as longfin tilapia O. macrochir. These results stress the importance of improving the knowledge of genetic variation within the native ranges of Oreochromis species for better-informed conservation of these natural resources.  相似文献   
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Abstract

The palladium-catalyzed cross-couplings of 2-chloro-3,5-diamino-6-iodopyrazine (1a) and methyl 3-amino-6-iodopyrazine-2-carboxylate (1b) with 1,4-anhydro-3,5-O-bis[(tert-butyl)dimethylsilyl]-2-deoxy-D-erythro-pent-1-enitol (2) followed by desilylation and stereospecific reduction of the 2′-deoxy-3′-keto adduct leads to the formation of 2-chloro-6-(2-deoxy-ß-D-ribofuranosyl)-3,5-diaminopyrazine (4a) and methyl 3-amino-6-(2-deoxy-ß-D-ribofuranosyl)pyrazine-2-carboxylate (4b) in 58% yield and 21% yield, respectively. These are the first syntheses of the heretofore unknown 2′-deoxy pyrazine C-nucleosides and demonstrate the utility of a convergent approach for the synthesis of pyrazine C-nucleosides.  相似文献   
77.
Abstract

Treatment of 4-(D-gluco-pentitol-l-y1)-2-pheny1–2H-1,2,3-triazole (1) with p-toluenesulfonyl chloride in pyridine solution, afforded the homo-C-nucleoside analog, 4-(2,5-anhydro-D-gluco-pentitol-1-yl)-2-phenyl-2H-1,2,3-triazole (2) as well as its partial p-toluenesulfonyl derivative (3). 4-(5-Chloro-5-deoxy-D-gluco-pentitol-1-yl)-2-phenyl-2H-1,2,3-triazole (8), was isolated as a byproduct from the reaction. The structure and anomeric configuration of 2 was determined by acylation, 1H, 13C NMR, and NOE, spectroscopy as well as mass spectrometry.

  相似文献   
78.
Abstract

A number of 2-substituted-5,6-dichloro-l-(α-L-arabinofuranosyl)benzimidazoles have been prepared by condensation of 2-bromo-5,6-dichlorobenzimidazole or 2,5,6-trichlorobenzimidazole with tetra-O-acetyl-L-arabinofuranose. 2-Alkylamino derivatives were prepared by a substitution of the 2-chloro group with the appropriate amines. All target compounds were evaluated for activity against HCMV and HSV-1. The 2-chloro and 2-bromo derivatives showed moderate activity against HCMV at non-cytotoxic concentrations.  相似文献   
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