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Bacterial blood culture results of 292 privately owned cats presented to the Clinic for Small Animal Medicine, Ludwig Maximilian University Munich with signs of sepsis were evaluated retrospectively. Of the blood cultures, 23% were positive. In 88%, a single bacterial species was isolated. Of all bacterial isolates, 45% were Gram-positive, 43% were Gram-negative, and 12% were obligate anaerobes. The most frequently isolated bacteria were Enterobacteriaceae, obligate anaerobic species, Staphylococcus species and Streptococcus species. Of the cats with positive blood cultures, 32% were pretreated with antibiotics. Of all bacterial isolates, 77% were susceptible to enrofloxacin, 69% to chloramphenicol, 67% to gentamicin, and 64% to amoxycillin clavulanic acid. Only enrofloxacin reached an in vitro efficacy of more than 70% against Gram-positive and more than 74% against Gram-negative bacteria. 相似文献
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The C isotopic composition (δ13C) of pedogenic carbonates reflects the photosynthetic pathway of the predominant local vegetation because pedogenic (secondary) CaCO3 is formed in isotopic equilibrium with soil CO2 released by root and rhizomicrobial respiration. Numerous studies show the importance of pedogenic carbonates as a tool for reconstructing paleoecological conditions in arid and semiarid regions. The methodological resolution of these studies strongly depends on the time scale of pedogenic carbonate formation, which remains unknown. The initial formation rate can be assessed by 14C labeling of plants grown on loess and subsequent incorporation of 14C from rhizosphere CO2 into newly formed carbonate by recrystallization of loess CaCO3. We tested the feasibility of 14C and 13C tracers for estimating CaCO3 recrystallization rates by simultaneous 14C and 13C labeling and comparison with literature data. 14C labeling was more efficient and precise in assessing recrystallization rates than 13C labeling. This is connected with higher sensitivity of 14C liquid scintillation counting when compared with δ13C measurement by IRMS. Further, assessment of very low amounts of incorporated tracer is more precise with low background signal (natural abundance), which is true for 14C, but is rather high for 13C. Together, we obtained better reproducibility, higher methodological precision, and better plausibility of recrystallization rates calculated based on 14C labeling. Periods for complete CaCO3 recrystallization, extrapolated from rates based on 14C labeling, ranged from 130 (125–140) to 240 (225–255) y, while it was ≈ 600 (365–1600) y based on the 13C approach. In terms of magnitude, data from late‐Holocene soil profiles of known age provide better fit with modeled recrystallization periods based on the 14C approach. 相似文献
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Martina Caramante Rosa Rao Luigi Maria Monti Giandomenico Corrado 《Scientia Horticulturae》2009,120(4):560-564
‘San Marzano’ (SM) is one of the most widely known tomato (Solanum lycopersicum L.) cultivars, and is a classic example of a local variety with a premium value. Unfortunately, the original cultivated form is underrepresented in the Protected Denomination of Origin (PDO) area because of the incidence of contaminant and phenotypically similar genotypes. Our aim was to examine the ability of three DNA marker systems (minisatellite, cleaved amplified polymorphic sequence (CAPS) and simple sequence repeat (SSR)) to reveal the genetic diversity of tomato accessions that were, based on a morphological analysis, very similar. The data indicate that both minisatellites and SSRs can be used to genetically distinguish the analysed materials. Furthermore, these two marker systems depict relationships consistent with the hierarchal pattern obtained by the morphological data. As locally cultivated tomato accessions are often characterised by some degree of genetic variability, our results will be valuable in facilitating the purification, management and breeding of tomato germplasms. The differences between the marker systems employed are also discussed in relation to their usefulness in the agro-food chain. 相似文献
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Hellal F Hurtado A Ruschel J Flynn KC Laskowski CJ Umlauf M Kapitein LC Strikis D Lemmon V Bixby J Hoogenraad CC Bradke F 《Science (New York, N.Y.)》2011,331(6019):928-931
Hypertrophic scarring and poor intrinsic axon growth capacity constitute major obstacles for spinal cord repair. These processes are tightly regulated by microtubule dynamics. Here, moderate microtubule stabilization decreased scar formation after spinal cord injury in rodents through various cellular mechanisms, including dampening of transforming growth factor-β signaling. It prevented accumulation of chondroitin sulfate proteoglycans and rendered the lesion site permissive for axon regeneration of growth-competent sensory neurons. Microtubule stabilization also promoted growth of central nervous system axons of the Raphe-spinal tract and led to functional improvement. Thus, microtubule stabilization reduces fibrotic scarring and enhances the capacity of axons to grow. 相似文献
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Some macadamia trees in a commercial orchard on the island of Hawaii showing symptoms of quick decline had club-shaped fruiting bodies of Xylaria arbuscula on the trunk. X arbuscula was consistently isolated from diseased wood and was shown to kill branches of healthy macadamia trees on inoculation. Trunk infection by this pathogen leading to girdling resulted in a more rapid decline than would be expected with root infection by soil-borne pathogens. 相似文献
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