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41.
García ME Caballero J Toni P Garcia I Martinez de Merlo E Rollan E Gonzalez M Blanco JL 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2000,47(4):243-249
We describe a case of canine mycoses initially diagnosed by clinical signs and enzyme-linked immunosorbent assay anti-fungal test, and later confirmed by the isolation of Paecilomyces sp. during the post-mortem examination. The fungus was isolated from lesions in the kidneys, mitral valve, abdominal aorta and vertebral discs. In this kind of process, it is important to identify the responsible agent early in order to make a study of anti-fungal susceptibility and establish effective treatment. 相似文献
42.
Verástegui M González A Gilman RH Gavidia C Falcón N Bernal T Garcia HH 《Veterinary parasitology》2000,94(1-2):33-44
A novel method for infecting pigs with Taenia solium using an intramuscular innoculum of oncospheres was investigated in a series of five experiments in 18 animals. The model is simple to perform, requires a minimal number of oncospheres, permits multiple infections per animal, and decreases the variation inherent in oral infection models. This intramuscular oncosphere assay (IMOA) may provide a valuable tool to evaluate therapeutic agents or potential vaccines for cysticercosis. 相似文献
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Despite the important role that canine skin mast cells play in IgE-mediated allergic inflammation, clinically useful compounds for modulating mediator release from these cells or for suppressing cell response are lacking in the dog. The ability of five compounds to inhibit histamine release induced by non immunological (calcium ionophore A23187 and substance P) and IgE-dependent (concanavalin A) stimuli were compared. Sodium cromoglycate, a mast cell stabilizer, and dexamethasone, a glucocorticoid, failed to inhibit histamine release from isolated skin mast cells following any kind of stimulation. Salbutamol, a β-adrenergic agonist, exhibited inhibitory activity (46.0%) only after concanavalin A activation. In contrast, rolipram, a selective phosphodiesterase IV inhibitor and cyclosporin A, an immunosuppressor, showed potent anti allergic actions, inhibiting both IgE-dependent and -independent stimuli. Rolipram inhibited 42.8%, 44.7% and 19.2% of the mediator release induced by ionophore A23187, substance P and concanavalin A, respectively. Similarly cyclosporin A induced 85.9%, 14.9% and 67.3% inhibition after ionophore A23187, substance P and concanavalin A stimulation, respectively. These results suggest that rolipram and cyclosporin A merit to be clinically tested as agents for the treatment of chronic allergic diseases in the dog. 相似文献
45.
Current payment for environmental service (PES) schemes face challenges in the form of evaluation of opportunity costs and ecosystem service delivery, high transaction costs, and difficulties in ensuring conditionality. Even when these conditions are met, PES may be undermined by a lack of inclusivity, leading to societal conflicts over land use. We propose a new PES-type approach that we call Landscape Labelling that seeks to overcome these problems by combining PES and product certification principles applied at a landscape scale with local benefits realized at the community level. 相似文献
46.
M. C. Makrakis L. E. Miranda S. Makrakis D. R. Fernandez J. O. Garcia J. H. P. Dias 《Ecology of Freshwater Fish》2007,16(3):410-416
Abstract – We studied the migratory behaviour of armado, Pterodoras granulosus , in the Paraná River Basin of Brazil, Paraguay and Argentina, during 1997–2005. This species invaded the Upper Paraná River after upstream dispersal was facilitated when Itaipu Reservoir inundated a natural barrier. Fish were tagged ( N = 8051) in the mainstems of the Yacyreta and Itaipu reservoirs, bays of major tributaries, the Paraná River floodplain above Itaipu Reservoir, and below dams. In all, 420 fish were recaptured of which 61% moved away from the release area. Fish moved a maximum of 215 km (mean 42), and at a maximum rate of 9.4 km·day−1 (mean 0.6). Of the 256 armados that moved away from the release site, 145 moved upstream towards unimpounded stretches of the Paraná River and 111 moved downstream into the reservoir and bays of its tributaries (maximum 150 km). Based on the observed migratory movements, we suspect that most of the reproductive output originates in tributaries to the reservoirs. The ability of this species to expand its range presents a conundrum by pitting fishery management interests against conservation needs. Maintenance of the important armado fisheries depends on the ability of the species to migrate freely to use spawning and nursery areas in reservoir tributaries and floodplains. However, its ability to migrate long distances can allow this non-native species the opportunity to invade most of the Upper Paraná River. 相似文献
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48.
Medium density fibreboard (MDF) was produced from fibres treated with maleated polypropylene wax. The objectives of this study were to investigate the effect of fibre treatment with maleated polypropylene wax on the advancing and receding contact angle and wicking of MDF panels by the Wilhelmy plate method; to verify the chemical reactions occurring between fibres and maleated polypropylene wax by infrared spectroscopy, and to verify if there are relationships with the water absorption of panels. Three maleated polypropylene wax contents (0, 3, 5%) and two resin types (urea–formaldehyde, UF and melamine–urea–formaldehyde, MUF) were considered in this study. Our results showed that the treatment increased the advancing contact angle of panels bonded with UF resin. The receding contact angles of MDF panels produced from treated fibres with 5% maleated polypropylene wax content were also increased by the treatment. Also, the wicking was reduced by the treatment independent of the maleated polypropylene wax content. Reductions of the wicking were 59% for panels bonded with UF resin and 73% for panels bonded with MUF. Relationships between the wicking and water absorption were observed. Chemical analysis realized by infrared spectroscopy did not detect the presence of an esterification reaction between wood fibres and anhydride groups of the maleated polypropylene wax. This suggests, therefore, that an esterification reaction did not take place or that chemical modifications were so small that they are not visible by infrared spectroscopy. 相似文献
49.
介绍了原木蒸煮废水的处理方法,提出氧化塘法是小型木材加工厂处理该废水的最佳选择,并用实例简单介绍了氧化塘的设计选型问题. 相似文献
50.
The antimicrobial activity of ethanol, acetone and aqueous extracts of the aerial parts of Pseudognaphalium moritzianum was evaluated. Ethanol and acetone extracts showed activity against Staphlococcus aureus, Enterococcus faecalis and Pseudomonas aeruginosa. The aqueous extract was active against S. aureus and P. aeruginosa. 相似文献