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1.
A dog with visceral leishmaniasis developed rear limb edema, and distension of the caudal epigastric veins. Glomerular disease with nephrotic syndrome and hypercoagulable state was diagnosed. Sonographically there was massive thrombosis of the caudal vena cava. 相似文献
2.
Soil physical changes and maize growth in a structurally fragile tropical soil due to mulching and duration between irrigation intervals 下载免费PDF全文
E. G. Moura V. R. A. Macedo V. G. L. Sena L. S. Campos A. C. F. Aguiar 《Soil Use and Management》2017,33(4):631-638
Under tropical meteorological conditions, the volume of soil explored by plant roots is crucial for crop growth as it allows increased water and nutrient use efficiency. We hypothesized that, under different irrigation intervals, leguminous mulch can extend the duration between irrigation events but maintain crop performance, because decreased evaporative fluxes also reduce constraints to root exploration imposed by mechanical stress. We evaluated the combined effects of leguminous mulch and irrigation intervals on soil physical properties to determine whether the growth and productivity of maize were modified in a structurally fragile tropical soil. The experiment involved the following treatments: 4‐day irrigation intervals with soil mulched (4C) or bare (4S), 6‐day irrigation intervals with soil mulched (6C) or bare (6S), 8‐day irrigation intervals with soil mulched (8C) or bare (8S) and 10‐day irrigation intervals with soil mulched (10C) or bare (10S). Mulch decreased soil penetration resistance and increased to 4 days the favourable time for root development in drying soil. Relative to bare soil, mulch with a 6‐day irrigation interval almost doubled nitrogen uptake post‐tasselling, which decreased nitrogen remobilization and increased the crop growth rate during this stage. These conditions had a positive effect on the transpiration rate and stomatal conductance as well as on the growth and yield of maize. A 6‐day irrigation interval with mulch compared to 4 days with bare soil resulted in similar conditions for root development, but greater uptake of nitrogen (102.73–78.70 kg/ha) and better yield (6.2–5.3 t/ha), which means greater efficiency in nitrogen and water use. 相似文献
3.
4.
Cholera toxin promotes the generation of semi-mature porcine monocyte-derived dendritic cells that are unable to stimulate T cells 总被引:2,自引:0,他引:2
Bimczok D Rau H Wundrack N Naumann M Rothkötter HJ McCullough K Summerfield A 《Veterinary research》2007,38(4):597-612
Cholera toxin (Ctx) is a powerful mucosal adjuvant with potential applications for oral vaccination of swine. Dendritic cells (DC) play a key role in the decision between immunity and tolerance, and are likely target cells for mediating Ctx functions in vivo. Therefore, we examined the capacity of Ctx to enhance stimulatory activity of porcine monocyte-derived DC (MoDC). Ctx promoted the development of a semi-mature DC phenotype, with decreased levels of MHC class II and CD40, but increased CD80/86 expression. These changes were associated with activation of extracellular signal-regulated kinase (ERK), but not NFkappaB or c-Jun N-terminal kinase (JNK). Functionally, Ctx-priming greatly diminished T cell stimulatory capacity both in antigen-specific and superantigen-induced proliferation assays. The lower proliferation rate was not due to increased apoptosis of either DC or T cells. Ctx suppressed TNFalpha secretion by MoDC, but induced IL-10 production. The observed effects on T cell proliferation could only be partially mimicked by IL-10 alone. However, addition of recombinant TNFalpha to co-cultures of Ctx-primed MoDC and lymphocytes restored lymphocyte proliferation in a concentration-dependent manner. Ctx-primed DC were not actively tolerogenic, since they could not suppress proliferative T cell reactions induced by untreated DC. 相似文献
5.
Natalia Siwinska Agnieszka Zak Malwina Slowikowska Artur Niedzwiedz Rafal Ciaputa Izabela Janus Marek Lipiec Lukasz Radulski Adam Szymerowski Marcin Nowak 《Equine Veterinary Education》2023,35(2):e61-e65
Bovine tuberculosis is a contagious and zoonotic disease of animals and humans. In Europe, the number of reported cases of tuberculosis has decreased. Equidae are relatively rarely infected even in endemic areas. The presented report describes a case of chronic Mycobacterium bovis tuberculosis in a 30-year-old female donkey. The donkey initially presented with persistent lymphadenopathy; however, as the disease progressed, weight loss became apparent. To the authors' knowledge, this is the second confirmed case of tuberculosis in a donkey in Europe. 相似文献
6.
Jorge Miguel Silva Faria Inês Sena Bruno Ribeiro Ana Margarida Rodrigues Carla Maria Nobre Maleita Isabel Abrantes Richard Bennett Manuel Mota Ana Cristina da Silva Figueiredo 《Journal of pest science》2016,89(1):207-217
The Columbia root-knot nematode (CRKN), Meloidogyne chitwoodi, is an EPPO A2 type quarantine pest since 1998. This nematode causes severe damage in economically important crops such as potato and tomato, making agricultural products unacceptable for the fresh market and food processing. Commonly used nematicidal synthetic chemicals are often environmentally unsafe. Essential oils (EOs) may constitute safer alternatives against RKN. EOs, isolated from 56 plant samples, were tested against CRKN hatching, in direct contact bioassays. Some of the most successful EOs were fractionated and the hydrocarbon molecules (HM) and oxygen-containing molecules (OCM) fractions tested separately. 24 EOs displayed very strong hatching inhibitions (≥90 %) at 2 µL mL?1 and were further tested at lower concentrations. Dysphaniaambrosioides, Filipendula ulmaria, Ruta graveolens, Satureja montana and Thymbra capitata EOs revealed the lowest EC50 values (<0.15 µL mL?1). The main compounds of these EOs, namely 2-undecanone, ascaridol, carvacrol, isoascaridol, methyl salicylate, p-cymene and/or γ-terpinene, were putatively considered responsible for CRKN hatching inhibition. S. montana and T. capitata OCM fractions showed hatching inhibitions higher than HM fractions. The comparison of EO and corresponding fractions EC50 values suggests interactions between OCM and HM fractions against CRKN hatching. These species EOs showed to be potential environmentally friendly CRKN hatching inhibitors; nonetheless, bioactivity should be considered globally, since its HM and OCM fractions may contribute, diversely, to the full anti-hatching activity. 相似文献
7.
Structural ripening-related changes of the arabinan-rich pectic polysaccharides from olive pulp cell walls 总被引:2,自引:0,他引:2
Cardoso SM Ferreira JA Mafra I Silva AM Coimbra MA 《Journal of agricultural and food chemistry》2007,55(17):7124-7130
In this study, the structural features and ripening-related changes that occur in the arabinan-rich pectic polysaccharides highly enmeshed in the cellulosic matrix of the olive pulp fruit were evaluated. These pectic polysaccharides, obtained from two consecutive harvests at green, cherry, and black ripening stages, account for 11-19% of the total pectic polysaccharides found in the olive pulp cell walls and were previously shown to occur as calcium chelating dimers. On the basis of the 13C NMR, (1H, 13C) gHSQC, 2D COSYPR, and (1H,13C) gHMBC carbon and proton resonances of the variously linked arabinosyl residues, we propose a tentative structure. This structure is particularly characterized by T-beta-Araf (1-->5)-linked to (1-->3,5)-Araf residues and by the occurrence of branched and linear blocks in the arabinan backbone. Methylation analysis showed that these pectic polysaccharides of black olives have more arabinan side chains, which were shorter (less (1-->5)-Araf), highly branched (more (1-->3,5)-Araf), and with shorter side chains (fewer (1-->3)-Araf) than those of green and cherry olives. Quantitative 13C NMR data indicated that these modifications involved the disappearance of the characteristic terminally linked beta-Araf residue of the arabinans. This odd feature can be used as a diagnostic tool in the evaluation of the stage of ripening of this fruit, as well as a marker for the presence of olive pulp in matrices containing pectic polysaccharides samples. 相似文献
8.
Sylwia Goławska Iwona Sprawka Iwona Łukasik Artur Goławski 《Journal of pest science》2014,87(1):173-180
The effects of two polyphenolic flavonoids (flavanone naringenin and flavonol quercetin) on development, fecundity, and mortality of the pea aphid, Acyrthosiphon pisum Harris (Hemiptera: Aphididae), were determined in vitro, on an artificial diets. Also determined in vitro (DC EPG method), on sucrose–agarose gels, were the effects of flavonoids on the probing and feeding behavior of adult apterae. When added to a liquid diet, higher concentrations of studied flavonoids increased the developmental time, the pre-reproductive period, and mortality and decreased fecundity and the intrinsic rate of natural increase of A. pisum. In most events associated with stylet activity (as indicated by EPG waveform g-C), differences in probing behavior did not statistically differ between the control gel and those with flavonoids; quercetin at 10, 100, and 1,000 µg cm?3 prolonged the number of gel penetrations; and quercetin only at 10,000 μg cm?3 prolonged the time the first g-C waveform was observed. Addition of flavonoids to the gels generally reduced passive ingestion from fluids of the gels (EPG waveform g-E2). At higher concentrations (>1,000 µg cm?3) the flavonoids completely stopped salivation (EPG waveform g-E1) and passive ingestion from fluids of the gels (EPG waveform g-E2). In events associated with active ingestion (EPG waveform g-G), however, differences in feeding behavior did not statistically differ between the control gel and those with flavonoids. The present findings demonstrate detrimental effects of the flavanone naringenin and flavonol on the behavior of the pea aphid. This can be employed in a biotechnological projects for plant breeding resistant to herbivores, including aphids. 相似文献
9.
Abstract The Australian native freshwater fish Murray cod, Maccullochella peelii pellii (Mitchell), currently supports a fledgling inland aquaculture industry, which is thought to have considerable growth potential. The aim of this study was to evaluate the suitability of two alternate protein sources [blood meal (BM) and defatted soybean meal (SBM)] as substitutes for fish meal at various levels of inclusion in diets for juvenile Murray cod. The growth performance of juvenile Murray cod in response to nine isonitrogenous and isocalorific diets (50% protein, 14% lipid, 20.2 kJ g?1) consisting of a control diet in which protein was supplied from fish meal, and test diets in which the fish meal protein was substituted at levels of 8%, 16%, 24%, and 32% with BM or SBM was evaluated from a 70‐day growth experiment. The per cent apparent dry matter (% ADCdm) and percentage protein digestibility (% ADCp) of the test diets were also determined using Cr2O3 as a marker. Survival in all the SBM dietary treatments was high but that of fish on the BM dietary treatments was significantly (P < 0.05) lower than in all the other dietary treatments. Specific growth rate (% day?1) of Murray cod fed SBM incorporated diets ranged from 1.63 ± 0.06 to 1.78 ± 0.10 and even at the highest level tested (32% of the dietary protein from SBM) was not significantly different (P > 0.05) from the fish fed the control diet (1.65 ± 0.09). Feed conversion ratios of the SBM dietary treatments ranged from 1.36 ± 0.08 to 1.45 ± 0.07. The protein efficiency ratios and protein conversion efficiencies of Murray cod in the soybean meal treatments were also good and for a majority of the SBM diets were better than those for the control diet. Per cent ADCdm and ADCp of the SBM diets tested ranged from 70.6 ± 1.46 to 72.3 ± 1.81% and 88.6 ± 0.57 to 90.3 ± 0.17%, respectively, and was not significantly different (P > 0.05) from the control diet (% ADCdm 74.3 ± 1.63; % ADCp 91.3 ± 0.55). The reasons for significantly poor survival and growth of Murray cod reared on BM incorporated diets, and relatively poor digestibility of these diets are discussed. The study shows that for Murray cod diets in which fish meal protein is substituted up to 32% performance or carcass composition is not compromised. 相似文献
10.
Giovanni M Turchini Rasanthi M Gunasekera & Sena S De Silva 《Aquaculture Research》2003,34(9):697-708
The efficacy of trout oil (TO), extracted from trout offal from the aquaculture industry, was evaluated in juvenile Murray cod Maccullochella peelii peelii (25.4±0.81 g) diets in an experiment conducted over 60 days at 23.7±0.8 °C. Five isonitrogenous (48% protein), isolipidic (16%) and isoenergetic (21.8 kJ g?1) diets, in which the fish oil fraction was replaced in increments of 25% (0–100%), were used. The best growth and feed efficiency was observed in fish fed diets containing 50–75% TO. The relationship of specific growth rate (SGR), food conversion ratio (FCR) and protein efficiency ratio (PER) to the amount of TO in the diets was described in each case by second‐order polynomial equations (P<0.05), which were: SGR=–0.44TO2+0.52TO+1.23 (r2=0.90, P<0.05); FCR=0.53TO2–0.64TO+1.21 (r2=0.95, P<0.05); and PER=–0.73TO2+0.90TO+1.54 (r2=0.90, P<0.05). Significant differences in carcass and muscle proximate compositions were noted among the different dietary treatments. Less lipid was found in muscle than in carcass. The fatty acids found in highest amounts in Murray cod, irrespective of the dietary treatment, were palmitic acid (16:0), oleic acid (18:1n‐9), linoleic acid (18:2n‐6) and eicosapentaenoic acid (20:5n‐3). The fatty acid composition of the muscle reflected that of the diets. Both the n‐6 fatty acid content and the n‐3 to n‐6 ratio were significantly (P<0.05) related to growth parameters, the relationships being as follows. Percentage of n‐6 in diet (X) to SGR and FCR: SGR=–0.12X2+3.96X–32.51 (r2=0.96) and FCR=0.13X2–4.47X+39.39 (r2=0.98); and n‐3:n‐6 ratio (Z) to SGR, FCR, PER: SGR=–2.02Z2+5.01Z–1.74 (r2=0.88), FCR=2.31Z2–5.70Z+4.54 (r2=0.93) and PER=–3.12Z2–7.56Z+2.80 (r2=0.88) respectively. It is evident from this study that TO could be used effectively in Murray cod diets, and that an n‐3:n‐6 ratio of 1.2 results in the best growth performance in Murray cod. 相似文献