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排序方式: 共有243条查询结果,搜索用时 31 毫秒
21.
A proposal of clinical breakpoints for amoxicillin applicable to porcine respiratory tract pathogens
Schwarz S Böttner A Goossens L Goosens L Hafez HM Hartmann K Kaske M Kehrenberg C Kietzmann M Klarmann D Klein G Krabisch P Luhofer G Richter A Schulz B Sigge C Waldmann KH Wallmann J Werckenthin C 《Veterinary microbiology》2008,126(1-3):178-188
In the present position paper, an attempt was made to establish clinical breakpoints of amoxicillin to classify porcine respiratory tract pathogens as susceptible, intermediate or resistant based on their minimum inhibitory concentrations of amoxicillin. For this, a thorough review of the published literature with regard to swine-specific pharmacological data (including dosages of amoxicillin applied and routes of administration used), clinical efficacy, and in vitro susceptibility of the target pathogens was performed. Based on the comparative analysis of the results, the working group "Antibiotic Resistance" of the German Veterinary Medical Society (DVG) proposed to classify porcine respiratory tract pathogens that show MIC values of amoxicillin of < or =0.5microg/ml as "susceptible", those with MICs of 1microg/ml as "intermediate", and those with MICs of > or =2microg/ml as "resistant". 相似文献
22.
Gradner G Weissenböck H Kneissl S Benetka V Dupré G 《Journal of Feline Medicine and Surgery》2008,10(1):88-94
A 4-year-old, male castrated European shorthair cat was presented with a firm mass palpable on the right caudal rib cage. Lateral and ventrodorsal radiographs of the thorax revealed a 4x3x2cm large, expansile and radiodense mass originating from the distal part of the 13th rib. After removal of the tumour, which was histopathologically confirmed as feline osteochondromatosis, the diaphragm, omentum, external abdominal oblique and latissimus dorsi muscles were used to reconstruct the defect. Feline osteochondromatosis is induced by retroviruses, eg, feline leukaemia virus, for which the cat tested positive. The tumour was removed for palliative reasons, because such tumours have the tendency to transform into osteosarcomas. Six months after the surgical excision the cat showed no clinical signs of reoccurrence. 相似文献
23.
In this study, the kinetics of soil organic matter (SOM) dissolution from soil samples in different states of moisture was investigated, using a continuous extraction method. The investigation distinguished three processes of SOM dissolution. They include an initial, fast process (probably hydrophilic dissolved organic matter) and two slow, rate limited processes, which probably correspond to hydrophobic dissolved organic matter (DOM). The second process indicates a slow, continuous release of DOM, whereas the third process is determined by a power law. The rate of the third process strongly depends on temperature and state of moisture. It is diffusion limited, with the diffusion control probably being located in the solid soil organic matter. This was explained by a gel structure, which slowly forms in the hydrating SOM and allows diffusion of mobile particles of SOM. The results show the importance of considering the moisture state of SOM for the kinetics of DOM dissolution. 相似文献
24.
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
25.
Gianluca Pane Gabriele Cacciola Elisabetta Giacco Gian Luigi Mariottini Erika Coppo 《Marine drugs》2015,13(10):6440-6452
External otitis is a diffuse inflammation around the external auditory canal and auricle, which is often occurred by microbial infection. This disease is generally treated using antibiotics, but the frequent occurrence of antibiotic resistance requires the development of new antibiotic agents. In this context, unexplored bioactive natural candidates could be a chance for the production of targeted drugs provided with antimicrobial activity. In this paper, microbial pathogens were isolated from patients with external otitis using ear swabs for over one year, and the antimicrobial activity of the two methanol extracts from selected marine (Dunaliella salina) and freshwater (Pseudokirchneriella subcapitata) microalgae was tested on the isolated pathogens. Totally, 114 bacterial and 11 fungal strains were isolated, of which Staphylococcus spp. (28.8%) and Pseudomonas aeruginosa (P. aeruginosa) (24.8%) were the major pathogens. Only three Staphylococcus aureus (S. aureus) strains and 11 coagulase-negative Staphylococci showed resistance to methicillin. The two algal extracts showed interesting antimicrobial properties, which mostly inhibited the growth of isolated S. aureus, P. aeruginosa, Escherichia coli, and Klebsiella spp. with MICs range of 1.4 × 109 to 2.2 × 1010 cells/mL. These results suggest that the two algae have potential as resources for the development of antimicrobial agents. 相似文献
26.
Gabriele Vaccari Gaia Scavia Marcello Sala Gianmario Cosseddu Barbara Chiappini Michela Conte Elena Esposito Raniero Lorenzetti Gabriella Perfetti Paola Marconi Francesco Scholl Katia Barbaro Antonino Bella Romolo Nonno Umberto Agrimi 《Veterinary research》2009,40(3)
The susceptibility of sheep to scrapie is under the control of the host’s prion protein (PrP) gene and is also influenced by the strain of the agent. PrP polymorphisms at codons 136 (A/V), 154 (R/H) and 171 (Q/R/H) are the main determinants of susceptibility/resistance of sheep to classical scrapie. They are combined in four main variants of the wild-type ARQ allele: VRQ, AHQ, ARH and ARR. Breeding programmes have been undertaken on this basis in the European Union and the USA to increase the frequency of the resistant ARR allele in sheep populations. Herein, we report the results of a multi-flock study showing the protective effect of polymorphisms other than those at codons 136, 154 and 171 in Sarda breed sheep. All ARQ/ARQ affected sheep (n = 154) and 378 negative ARQ/ARQ controls from four scrapie outbreaks were submitted to sequencing of the PrP gene. The distribution of variations other than those at the standard three codons, between scrapie cases and negative controls, was statistically different in all flocks. In particular, the AT137RQ and ARQK176 alleles showed a clear protective effect. This is the first study demonstrating a protective influence of alleles other than ARR under field conditions. If further investigations in other sheep breeds and with other scrapie sources confirm these findings, the availability of various protective alleles in breeding programmes of sheep for scrapie resistance could be useful in breeds with a low frequency of the ARR allele and would allow maintaining a wider variability of the PrP gene. 相似文献
27.
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
28.
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
29.
Matthias Westerschulte Carl-Philipp Federolf Dieter Trautz Gabriele Broll Hans-Werner Olfs 《Journal of plant nutrition》2018,41(11):1381-1396
Slurry injection below the maize (Zea mays L.) row may substitute a mineral nitrogen (N) phosphorus (P) starter fertilizer (MSF) and thus reduce nutrient surpluses in regions with intensive livestock husbandry. We investigated the plant P, zinc (Zn), and manganese (Mn) status compared to the current farm practice. In 2014 and 2015 field trials were conducted to evaluate plant nutrient status at different growth stages. Besides an unfertilized control, two slurry injection treatments (±nitrification inhibitor (NI)) were compared to slurry broadcast application plus MSF. In both experiments NI addition significantly increased nutrient concentrations during early growth (6-leaf 2015: +33% P, +25% Zn, +39% Mn). Under P deficiency due to cold weather conditions broadcast application showed higher P uptake until 6-leaf (36–58%), while it was lower at 8- (32%) and 10-leaf (19%) stage compared to slurry injection (+NI). Zn availability was enhanced for slurry injection (+NI) during early growth and Zn and Mn uptakes were higher at harvest. Slurry injection decreased P balances by 10–14 kg P ha?1, while Zn and Mn balances were excessive independent of treatments. Slurry injection (+NI) can substitute a MSF without affecting early growth and enhances the Zn and Mn status. This new fertilizing strategy enables farmers to reduce P surpluses. 相似文献
30.
IMAGING DIAGNOSIS—ULTRASONOGRAPHIC APPEARANCE OF SKELETAL MUSCLE METASTASES IN A DOG WITH HEMANGIOSARCOMA
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Martina Fabbi Stefano Di Palma Sabrina Manfredi Giacomo Gnudi Francesca Miduri Eleonora Daga Gabriele Costantino Melis Ezio Bianchi Simone Voccia Antonella Volta 《Veterinary radiology & ultrasound》2017,58(6):E64-E67
A 13‐year‐old spayed female German shepherd dog was presented for acute onset of lethargy, anorexia, and disseminated erythematous skin lesions. Thoracic radiographs and abdominal ultrasonographic findings were consistent with metastatic hemangiosarcoma. Multiple, ill‐defined, irregularly shaped hypoechoic nodules were also detected within the thoracic and abdominal wall. Hemangiosarcoma metastases to the skeletal muscle were confirmed based on histopathological examination. Multivisceral involvement was also confirmed by necropsy. Metastatic neoplasia should be considered as a differential diagnosis for dogs with ill‐defined, irregular, hypoechoic, intramuscular nodules. 相似文献