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Pleuritis in slaughter pigs has increased in recent years in the Netherlands. The aim of the present study was to determine what respiratory pathogens were involved in pleuritis.In total, lungs of 968 slaughter pigs from 10 herds with high prevalence of pleuritis were morphologically examined for size, location, and type of lesions. Moreover, histology and bacteriology were performed.Examination of gross lung lesions showed 45% pleuritis, 14% pleuropneumonia and 38% catarrhal pneumonia. Peribronchiolar cuffing was found in 61 of 142 samples. Actinobacillus pleuropneumoniae was cultured from 22 lung samples from four herds. Pasteurella multocida was cultured from 55 lung samples in eight herds. No specific pattern with respect to the causal pathogens was found.In conclusion, no single infectious cause of pleuritis was found. A variety of infectious agents combined with environmental factors should be considered as a cause of pleuritis.  相似文献   
2.
The objective of this project was to develop a vision system that could predict when crawfish will molt. Different sections of the crawfish shell were examined to determine how the color changed as the time of molting approached. A strip on the tail section of the crawfish showed the greatest, most consistent color change. The average red/green × red/blue ratio decreased for every crawfish as the molting time approached. Using this ratio as a predictor, it was possible to predict the molting of a crawfish within 3 d with an accuracy greater than 80%. The limitation on accuracy was primarily the result of the large variations in natural shell color among the crawfish.  相似文献   
3.
Soybeans were germinated on a kilogram-scale, by the application of malting technology used in the brewing industry, and concomitantly challenged with Rhizopus microsporus var. oryzae. In a time-course experiment, samples were taken every 24 h for 10 days, and the isoflavonoid profile was analyzed by RP-UHPLC-MS. Upon induction with R. microsporus, the isoflavonoid composition changed drastically with the formation of phytoalexins belonging to the subclasses of the pterocarpans and coumestans and by prenylation of the various isoflavonoids. The pterocarpan content stabilized at 2.24 mg of daidzein equivalents (DE) per g after ~9 days. The levels of the less common glyceofuran, glyceollin IV, and V/VI ranged from 0.18 to 0.35 mg DE/g and were comparable to those of the more commonly reported glyceollins I, II, and III (0.22-0.32 mg DE/g) and glycinol (0.42 mg DE/g). The content of prenylated isoflavones after the induction process was 0.30 mg DE/g. The total isoflavonoid content increased by a factor of 10-12 on DW basis after 9 days, which was suggested to be ascribable to de novo synthesis. These changes were accompanied by a gradual increase in agonistic activity of the extracts toward both the estrogen receptor α (ERα) and ERβ during the 10-day induction, with a more pronounced activity toward ERβ. Thus, the induction process yielded a completely different spectrum of isoflavonoids, with a much higher bioactivity toward the estrogen receptors. This, together with the over 10-fold increase in potential bioactives, offers promising perspectives for producing more, novel, and higher potency nutraceuticals by malting under stressed conditions.  相似文献   
4.
Floodplains along large European rivers are diffusely polluted with heavy metals due to emissions in the past. Because of low mobility of heavy metals in floodplain soils and improvements of water quality, these pollutants will remain in place, and can gradually become covered with less contaminated sediments. Bioturbators, especially earthworms, can play an important role in the mixing and surfacing of contaminated substrate. Surfaced substrate can be redistributed by recurrent flooding events, even to areas outside the floodplain. The question remained to what extent bioturbation by small mammals contributes to the redistribution of heavy metals from river sediments in floodplains. Extensive fieldwork on bioturbators such as voles, moles and earthworms and their distribution patterns, as well as on sediment deposition and bioturbation, was conducted at the ‘Afferdensche en Deestsche Waarden’ floodplain over the years 2001–2003. Field data were combined with data of experiments in field enclosures and substrate columns to calculate the amounts of sediment and heavy metals (Zn, Cu, Pb and Cd) redistributed during the floods as well as on an annual basis. Moles and voles surfaced considerable amounts of substrate and heavy metals, but not as much as earthworms which contribute a substantial proportion of the total deposition and redistribution during floods. Although the impact of moles and voles on the redistribution during floods was only locally important, on an annual basis the bioturbation activity of especially moles in floodplains cannot be neglected. The annual amounts of substrate and heavy metals surfaced by all investigated bioturbators were even larger than the total amounts of substrate and heavy metals deposited during floods.  相似文献   
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