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排序方式: 共有244条查询结果,搜索用时 0 毫秒
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Gabriele Vaccari Cynthia H. Panagiotidis Cristina Acin Simone Peletto Francis Barillet Pierluigi Acutis Alex Bossers Jan Langeveld Lucien van Keulen Theodoros Sklaviadis Juan J. Badiola Olivier Andr��oletti Martin H. Groschup Umberto Agrimi James Foster Wilfred Goldmann 《Veterinary research》2009,40(5)
Scrapie is a fatal, neurodegenerative disease of sheep and goats. It is also the earliest known member in the family of diseases classified as transmissible spongiform encephalopathies (TSE) or prion diseases, which includes Creutzfeldt-Jakob disease in humans, bovine spongiform encephalopathy (BSE), and chronic wasting disease in cervids. The recent revelation of naturally occurring BSE in a goat has brought the issue of TSE in goats to the attention of the public. In contrast to scrapie, BSE presents a proven risk to humans. The risk of goat BSE, however, is difficult to evaluate, as our knowledge of TSE in goats is limited. Natural caprine scrapie has been discovered throughout Europe, with reported cases generally being greatest in countries with the highest goat populations. As with sheep scrapie, susceptibility and incubation period duration of goat scrapie are most likely controlled by the prion protein (PrP) gene (PRNP). Like the PRNP of sheep, the caprine PRNP shows significantly greater variability than that of cattle and humans. Although PRNP variability in goats differs from that observed in sheep, the two species share several identical alleles. Moreover, while the ARR allele associated with enhancing resistance in sheep is not present in the goat PRNP, there is evidence for the existence of other PrP variants related to resistance. This review presents the current knowledge of the epidemiology of caprine scrapie within the major European goat populations, and compiles the current data on genetic variability of PRNP. 相似文献
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Hidalgo Carcedo C Bonazzi M Spanò S Turacchio G Colanzi A Luini A Corda D 《Science (New York, N.Y.)》2004,305(5680):93-96
Organelle inheritance is an essential feature of all eukaryotic cells. As with other organelles, the Golgi complex partitions between daughter cells through the fission of its membranes into numerous tubulovesicular fragments. We found that the protein CtBP3/BARS (BARS) was responsible for driving the fission of Golgi membranes during mitosis in vivo. Moreover, by in vitro analysis, we identified two stages of this Golgi fragmentation process: disassembly of the Golgi stacks into a tubular network, and BARS-dependent fission of these tubules. Finally, this BARS-induced fission of Golgi membranes controlled the G2-to-prophase transition of the cell cycle, and hence cell division. 相似文献
4.
Henrik Harms Barbora Orlikova Seungwon Ji Damun Nesaei-Mosaferan Gabriele M. K?nig Marc Diederich 《Marine drugs》2015,13(8):4949-4966
The Ascomycota Dichotomomyces cejpii was isolated from the marine sponge Callyspongia cf. C. flammea. A new gliotoxin derivative, 6-acetylmonodethiogliotoxin (1) was obtained from fungal extracts. Compounds 2 and 3, methylthio-gliotoxin derivatives were formerly only known as semi-synthetic compounds and are here described as natural products. Additionally the polyketide heveadride (4) was isolated. Compounds 1, 2 and 4 dose-dependently down-regulated TNFα-induced NF-κB activity in human chronic myeloid leukemia cells with IC50s of 38.5 ± 1.2 µM, 65.7 ± 2.0 µM and 82.7 ± 11.3 µM, respectively. The molecular mechanism was studied with the most potent compound 1 and results indicate downstream inhibitory effects targeting binding of NF-κB to DNA. Compound 1 thus demonstrates potential of epimonothiodiketopiperazine-derived compounds for the development of NF-κB inhibitors. 相似文献
5.
Dariano Krummenauer Tzachi Samocha Luis Poersch Gabriele Lara Wilson Wasielesky 《Journal of the World Aquaculture Society》2014,45(1):3-14
The use of the same water over multiple culture cycles in a biofloc technology system can be highly beneficial. This study evaluated the effect of different levels of biofloc‐rich water on selected water quality indicators and on the productive performance of Pacific white shrimp, Litopenaeus vannamei, juveniles (3.5 g) stocked at 312 juveniles/m3 and cultured under conditions of no water exchange. The study was performed over a 30‐d period in an 800‐L tank system. A total of four biofloc enrichment levels (25, 50, 75, and 100%) and control (0%) were tested with three replicates each. Significant differences in nitrogen compounds were found between the biofloc‐enriched water and the zero‐enrichment treatment. No statistically significant differences among the biofloc‐enriched treatments were found in survival, final weight (8.25 g), and feed conversion ratio (FCR) (1.08). The shrimp raised in clear seawater (i.e., a 0% biofloc enrichment) were significantly smaller (7.37 g vs. 8.25 g) and showed a higher FCR (1.52 vs. 1.08) than the shrimp cultured in the biofloc‐rich water. Nevertheless, no differences in yields were found between treatments. The results of this study suggest that culture in biofloc‐enriched water produces higher levels of water quality and shrimp performance than culture in natural seawater. 相似文献
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Christoph Stephan Schmidt Mohamadali Alavi Massimiliano Cardinale Henry Müller Gabriele Berg 《Biology and Fertility of Soils》2012,48(8):947-960
Stenotrophomonas rhizophila DSM14405T is of high biotechnological interest as plant growth stimulator, especially for salinated conditions. The objective of this study was to determine the effect of plant species (cotton, tomato, and sweet pepper) on colonisation and plant growth promotion of this beneficial bacterium in gnotobiotic systems and in non-sterile soil. All plant structures (leaves, stems, and roots) were densely colonised by DSM14405T reaching up to 109 cells g?1 fresh weight; under gnotobiotic conditions the abundances were 4–5 orders of magnitude higher than in non-sterile soil. Under non-sterile conditions and ambient humidity, tomato shoots were more densely colonised than shoots of sweet pepper and cotton. S. rhizophila DSM14405T was shown to grow endophytically and colonise the vicinity of root hairs of tomato. Plant growth promotion was particularly apparent in tomato. In general, the impact of plant species on colonisation and plant growth promotion was more pronounced in soil than under gnotobiotic conditions and likely due to the control of diseases and deleterious microorganisms. S. rhizophila DSM14405T was shown to control diseases in sweet pepper and in cotton. Molecular profiling via single strand conformation polymorphism of internal transcribed spacers and 16S rRNA genes (PCR-single strand conformational polymorphism (SSCP)) revealed that S. rhizophila DSM14405T strongly affected fungal, but not bacterial communities in the rhizosphere of tomato and sweet pepper. Major SSCP bands related to uncultured fungi and Candida subhashii, disappeared in tomato rhizosphere after Stenotrophomonas treatment. This suggests an indirect, species-specific plant growth promotion effect of S. rhizophila via the elimination of deleterious rhizosphere organisms. 相似文献
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Sabina Morkramer Gabriele Hörstgen-Schwark H.J. Langholz 《Aquaculture (Amsterdam, Netherlands)》1985,44(4):303-320
Growth and carcass quality of European rainbow trout populations were compared in a full sib family test over five experimental periods. In total, 131 full-sib families of 17 different populations, (i.e. 19 500 fish), were included. A special system for family testing in trout was developed. This consisted of separate hatching of single pair matings, separate rearing of families up to marketable size and common fattening under two stocking densities. Thus, growth was studied separately for the rearing and the fattening period. The observed differences in rearing and fattening weight between and within populations were quite distinct and of significance for production and breeding efficiency. Similar ranking of populations after fattening in different years and under different stocking densities indicated that the final weight was highly genetically controlled. Carcass characteristics determined at marketable size showed somewhat smaller differences between populations. Populations with the highest fattening weight did not generally produce the most valuable carcasses. The results are discussed with respect to their impact on breeding strategies. 相似文献
10.
Soil microbial processes and Testacea (Protozoa) as indicators of heavy metal pollution The influence of the emissions from a copper smelter on soil microbial processes was investigated at 4 meadow sites along a concentration gradient in Brixlegg (Austria). The first site is within 300 m of the source, further sites are situated 1125 m, 2425 m and 5900 m from the smelter. Heavy metal pollution close to the smelter induced a decrease of microbial biomass, respiration, dehydrogenase activity and the related enzyme activities in soil samples (5–10 cm soil depth): Protease, alkaline phosphatase, arylsulfatase, actual and potential nitrification. Thus, soil microbial processes in the 5–10 cm layer appear to be directly affected by heavy metals. Regarding the testate amoebae, their low individual and species numbers at 5–10 cm soil depth obstruct clear trends of this animal group. However, comparing the heavy polluted site with the control area, abundances, species numbers and biomass of testate amoebae slightly decreased at the polluted site (5–10 cm). Contrary to the results in the 5–10 cm layer, most soil microbial processes as well as abundances, species numbers and biomass of testaceans in the upper soil (0–5 cm) seem to be more strongly influenced by the supply of organic substrate than by the content of heavy metals in the soil. 相似文献