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991.
Rauw F Anbari S van den Berg T Lambrecht B 《Veterinary immunology and immunopathology》2011,143(1-2):27-37
The detection of ChIFN production after ex vivo antigenic-stimulation of T-lymphocytes has been evaluated for the first time, as a tool to assess cell-mediated immunity (CMI) after avian influenza (AI) infection in 10-day-old SPF chickens. Preliminarily, recall antigens have been produced either by concentrating and inactivating the whole virus or by dissociating the viral proteins. Biologically and structurally intact forms of the viral proteins were isolated by non-ionic detergents while heating, chemical agents and ionic detergent used for virus inactivation altered the antigenic viral components. The n-octyl-B-D-gluco-pyranoside treatment at low temperature was very efficient to produce AI antigenic proteins used for evaluation of ChIFN production after ex vivo antigenic-stimulation of splenic and peripheral lymphocytes. In addition, protocols to isolate lymphocytes from the respiratory tract - the trachea and the lung - have been adapted for local CMI evaluation after similar ex vivo recall assay. Specific AI CMI in the spleen, the blood and the lung was detected for 5 weeks after low pathogenic AI (LPAI) infection in chickens, while further development is needed for tracheal CMI measurement. 相似文献
992.
Histological alterations in gills of shrimp Litopenaeus vannamei in low‐salinity waters under different stocking densities: Potential relationship with nitrogen compounds 下载免费PDF全文
Marcela G. Fregoso‐López María S. Morales‐Covarrubias Miguel A Franco‐Nava Javier Ramírez‐Rochín Juan F Fierro‐Sañudo Jesús T Ponce‐Palafox Federico Páez‐Osuna 《Aquaculture Research》2017,48(12):5854-5863
Two experimental modules with different stocking densities (M1 = 70 and M2 = 120 shrimp /m2) were examined weekly over a culture cycle in tanks with low‐salinity water (1.9 g/L) and zero water exchange. Results showed survival rates of 87.7 and 11.9% in M1 and M2, respectively. Water temperature, pH, dissolved oxygen, electrical conductivity and chlorophyll a were not significantly (p > .05) different between modules. In contrast, the concentrations of nitrogen compounds were significantly (p < .05) different between modules, except nitrite‐N (M2 were 2.31 ± 1.38 mg/L N‐TAN, 0.18 ± 0.49 mg/L N‐NO2? and 6.83 ± 6.52 mg/L N‐NO3?; in M1: 0.97 ± 0.73 mg/L N‐TAN, 0.05 ± 0.21 mg/L N‐NO2? and 0.63 ± 0.70 mg/L N‐NO3?). When waters of both modules reached higher levels of ammonia and nitrite, histological alterations were observed in gills. The histological alterations index (HAI) was higher in M2 (5‐112) than in M1 (2‐22). 相似文献
993.
994.
Chianini F Majó N Segalés J Domínguez J Domingo M 《Veterinary immunology and immunopathology》2003,94(1-2):63-75
The lymphoid, renal, pulmonary, and hepatic lesions of naturally occurring postweaning multisystemic wasting syndrome (PMWS) affected pigs have been studied by means of immunohistology. Ten conventionally reared pigs showing acute clinical signs of PMWS were selected from a farm on which animal were seronegative to porcine reproductive and respiratory virus and to Aujeszky's disease virus. All pigs were positive in tests for porcine circovirus type 2 by ISH and IHC. Monoclonal and polyclonal antibodies to CD3, CD79alpha, CD45RA (3C3/9), lysozyme, SLA-II-DQ (BL2H5), and MAC387 were used to characterise cells in PMWS lesions. The most relevant changes were reduction or loss of B and T lymphocytes, increased numbers of macrophages, and partial loss and redistribution of antigen presenting cells throughout lymphoid tissues compared to uninfected controls. The characteristics of lymphoid lesions in the present study strongly suggest an immunosuppressive effect of PMWS in affected pigs. 相似文献
995.
Pablo Vásquez Gassibe Raul Fraile Fabero María Hernández-Rodríguez Juan Andrés Oria-de-Rueda Felipe Bravo Oviedo Pablo Martín-Pinto 《Journal of Forest Research》2014,19(3):348-356
This study was aimed at describing post-fire mushroom production in a Mediterranean ecosystem dominated by Pinus pinaster Ait. in the northwest of Spain and assessing the results by classificatory models. During the autumn periods of 2003–2006, fruit bodies from 115 fungal taxa were collected in burned and unburned areas and were further grouped into the following categories: saprotrophic/mycorrhizal; and edible/non-edible. After wildfires, a significant reduction in the number of fungal species and fruit body biomass production was observed. Based on this relevant information, the first simple classificatory model for this aim is provided. Nine alternative models based on classifications according to combinations of edibility and functional groups were fitted, and four fruiting body biomass production classes were defined as possible responses. As explanatory factors, time after fire and climatic variables significantly related to fruit body production were included. The best predictive results were obtained for edible and edible-mycorrhizal models, for which the correct classification rate of production classes was between 92 and 85 %. Moreover, the models obtained were applied to analyse the effect of time after fire on fungal production. Mycorrhizal and edible fungal production after fire was classified into the lowest class, whereas saprotrophic and non-edible species followed a contrary trend. The classificatory models can be useful to optimise management and harvest of these increasingly appreciated non-timber forest resources. 相似文献
996.
997.
Twelve profiles were obtained from a 2 ha field, 6 from where Cu had been applied for 15 yr and 6 from areas not fertilized with Cu. The 30 to 50 cm layers in the profiles in both areas contained similar amounts of Cu indicating a lack of vertical migration of the fertilizer metal under field conditions. A buried layer of humified material was found mostly between 50 and 60 cm depth. Of the mineral elements which enriched this layer during degradation and humification, perhaps a few thousand years ago, Cu, Pb and Mn were apparently retained more than Ca, Fe, Ni, Al, Mg, Zn and K. 相似文献
998.
John R. Sheedy Sébastien Lachambre David K. Gardner Robert W. Day 《Aquaculture International》2016,24(2):503-521
The effect of a short-term feeding and starvation experiment on juvenile abalone (Haliotis rubra × H. laevigata) was investigated (average length = 67 mm; average weight = 48 g). All aquaculture experiments were conducted at The University of Melbourne, Australia. Artificial feed was supplied ad libitum to the fed group, and no feed was supplied to the starved group. A modified metabolite extraction protocol using deuterated solvents was developed for 1H-NMR-based metabolite profiling of digestive gland in response to the short-term feeding/starvation experiment, to avoid lyophilisation prior to biochemical analysis. PLS-DA revealed that fed and starved abalone are metabolically distinct from each other after 28 and 56 days. After 28 days, the fed group was defined by an increase in arginine, glucose, glutamate, glycine, inosine and uracil (P < 0.05), and the starved group was defined by an increase in N,N-dimethylglycine. After 56 days, the fed group still displayed increased glucose (P < 0.05), while N,N-dimethylglycine remained elevated in the starved group (P < 0.05). Arginine and glycogen were all higher at 28 days compared to 56 days, suggesting decreased anaerobic energy production at the later time point. Only glucose and N,N-dimethylglycine were significantly different between the fed and starved groups after 56 days, suggesting that abalone had not acclimatised to the starvation treatment after 28 days. These results infer N,N-dimethylglycine is a robust marker for short-term starvation in abalone. 1H-NMR was also conducted on the artificial feed and starved abalone faecal matter, revealing the biochemical differences between them and digestive gland tissue. These methodology and results will facilitate a deeper understanding of the nutritional and physiological requirements of abalone in an aquaculture setting. 相似文献
999.
Mobility and distribution of lead (Pb) were investigated in cucumber (Cucumis sativus L.) grown in solution culture. Based on the observation that Pb uptake is influenced by the chemical form of iron (Fe) (complexed or ionic) in the solution, Fe distribution was also determined. Iron concentration was even in the stem (separated to internodes) and petioles but slightly increased at the shoot tip while Pb concentration decreased upwards. In the leaves Fe concentration decreased upwards (whereas in the control it increased a little at the youngest leaves) while Pb concentration increased to the largest leaves then decreased towards the shoot tip. It is suggested that the distribution of Pb in cucumber is passive process and it accumulates in the apoplast while Fe distribution is determined by the requirements of synthetic processes in young or photosynthesizing tissues. Lead probably lowers Fe transport into the symplast in the leaves causing slight chlorosis at the youngest leaves. In the plants that were loaded with Pb, decapitated and rooted again in Pb‐free culture solution we found no significant remobilization of Pb which supports that Pb binds strongly to the binding sites in the apoplast or is detoxified in an immobile form. 相似文献
1000.
Brunet MJ Bladé C Salvadó MJ Arola L 《Journal of agricultural and food chemistry》2002,50(9):2708-2712
The processes of absorption, blood transport, tissular distribution, metabolism, and excretion are at present understood very little. The aim of this study was to investigate blood transport and identify which principal plasma proteins in humans and rats bind to monomeric catechin and procyanidins in red wine ex vivo. Human and rat plasma and serum were incubated with (+)-catechin and procyanidins from grape seed, the origin of red wine catechins. Proteins were separated by SDS-PAGE and native-PAGE to determine which proteins bound to these compounds. The principal protein that bound to (+)-catechin in each species was sequenced. SDS-PAGE showed that (+)-catechin and procyanidins mainly bound to a protein of about 80 kDa in rats and 35 kDa in humans. Their sequencing indicated that these proteins were apo A-I in humans and transferrin in rats. The fact that red wine procyanidins bind to both proteins suggests that they may have a role in reverse cholesterol transport and in the oxidizing action of iron. 相似文献