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1.
2.
The effect of three annually consecutive additions of pig slurry at two rates (90 and 150 m3 x ha(-1) x year(-1) on soils and soil humic acids (HAs) was investigated in a field experiment under semiarid conditions. Soils and pig slurries were analyzed by standard methods. The HAs were isolated from soils and pig slurry by a conventional procedure based on alkaline extraction, acidic precipitation to pH 1, purification by repeated alkaline dissolutions and acidic precipitations, water washing, dialysis, and final freeze-drying. The HAs obtained were analyzed for elemental (C, H, N, S, and O) and acidic functional group (carboxylic and phenolic) composition, and by UV-vis, FT-IR, fluorescence, and ESR spectroscopies. With respect to the control soil, the pig slurry amended soils had greater pH and electrical conductivity, slightly larger total N content, and smaller values of C/N ratio. A decrease of total organic C was observed only in soils amended for 2 and 3 years at the higher slurry rate. With respect to control soil HA, pig slurry HA was characterized by larger contents of S- and N-containing groups, smaller acidic functional group and organic free radical contents, a prevalent aliphatic character, extended molecular heterogeneity, and smaller aromatic polycondensation and humification degrees. Amendment with pig slurry HA determines a number of modifications in soil HAs, including increase of C, S, and COOH contents, C/N ratios, and aliphaticity and decrease of extraction yields and N, O, phenolic OH, and organic free radical contents. These effects are generally more evident after the first year of slurry application and tend to disappear with increasing number of treatments. Most probably, over the years the slightly humified slurry HA is mineralized through extended microbial oxidation, whereas only the most recalcitrant components, such as S-containing, phenolic, and aliphatic structures, are partially accumulated by incorporation into soil HA.  相似文献   
3.

Background

The authors report the first case of feline gastric actinomycosis associated with infection by Actinomyces hordeovulneris.

Case presentation

A 4-year-old, neutered male, semi-feral European cat, with a 1 year history of chronic vomiting, was referred to the clinic. Abdominal ultrasound examination identified a hypoechoic focal transmural thickening with loss of normal wall layering and hyperechoic speckles at the gastric body. Initial gastroscopic examination showed a tumour-like gastric mass with an ulcerated depression at the level of the greater curvature. Histologic examination of endoscopic biopsy specimens was consistent with a severe lymphoplasmacytic gastritis. After 2 months, due to persistence of abdominal discomfort, surgical exploration and intraoperative sampling of gross abnormalities was recommended. Full thickness gastric wall biopsies, and fine needle aspiration of the gastric thickening and gastric lymph node, were performed. Histopathological examination identified a transmural pyogranulomatous gastritis. Aspirate samples of the gastric wall cultured positive, with colony morphology, biochemical testing and PCR of the 16 s rRNA gene compatible with Actinomyces hordeovulneris. After 4 months of treatment with cefovecin (8 mg/kg subcutaneously every 14 days), the vomiting completely resolved, as well as the ultrasonographic gastric alteration.

Conclusion

This case report of feline gastric actinomycosis, caused by Actinomyces hordeovulneris, suggests that gastric bacterial infection should be considered in cases of focal gastric wall thickening associated with chronic vomiting in the cat, which may otherwise closely resemble neoplastic disease. Once a diagnosis of actinomycosis was obtained, a correct treatment with antibiotic therapy can resolve it.
  相似文献   
4.
Abstract. An enzyme-linked immunosorbent assay (ELISA) for the demonstration of the virus of spring viraemia of carp (SVCV) in liver, kidney and spleen homogenates, and in infected cell cultures is described. The sensitivity of the method is 102·8–103·5 TCID50 0·lml−1 of the examined fluid. The specificity has been confirmed by the ELISA inhibition test and by results of virological examinations. Contamination with bacteria or fungi of samples taken from dead fish had no effect on the results of ELISA. Specific anti-SVCV sera were used successfully for the production of conjugates for the direct immunoperoxidase and immunofluorescence detection of SVCV in infected cell cultures.  相似文献   
5.
The residual effects of adding 40 t ha–1 sewage sludge (SL) to a degraded soil cropped with barley were investigated after 9 and 36 months in a field experiment under semiarid conditions. The principal soil properties were apparently still affected by SL amendment 9 months after application but the effects disappeared after 36 months. With respect to control soil humic acids (HAs), the SL-HA was characterized by higher contents of S- and N-containing groups, smaller contents of acidic groups, a prevalent aliphaticity, extended molecular heterogeneity, and smaller degrees of aromatic polycondensation and humification. Amendment with SL caused an increase in N, H, S and aliphaticity contents and a decrease in C/N ratios and O and acidic functional group contents in soil HAs isolated 9 months after SL application. These effects tended to decrease after 36 months, most probably because the slightly humified SL-HA was mineralised over time through extended microbial oxidation, while only the most recalcitrant components such as S-containing and aromatic structures were partially accumulated by incorporation into soil HA. Microbial biomass, basal respiration, metabolic quotient and enzymatic activities increased in soil 9 months after SL application, possibly because of increased soil microbial metabolism and enhanced mineralisation processes. After 36 months these properties returned to values similar to those of the unamended soil, presumably due to the loss of energy sources.  相似文献   
6.
This study examined the spatiotemporal immune response in listeric rhombencephalitis of ruminants in situ. Our data support the view that astrocytes facilitate the containment of infectious lesions. Results on the natural disease recapitulate observations in experimental rodent models and suggest that the mounted adaptive lymphocytic response of ruminants is effective in eliminating Listeria monocytogenes (LM). However, our data indicate earlier participation of the adaptive immune response, a stronger B lymphocyte contribution and a more protracted macrophage infiltration in the natural disease than it has been deduced from experimental models. Therefore, such models should be complemented by studies in natural host systems. Various macrophage and microglia subsets are involved in listeric rhombencephalitis and their differential contribution may account for species differences in clinical course and outcome of infection as might species differences in the B-cell response. Future functional ex vivo and in vitro studies are necessary to further investigate the findings obtained in the present study.  相似文献   
7.
AIM: To describe a disease of muscle in Charolais calves and confirm the putative diagnosis of inherited myophosphorylase deficiency.

METHODS: Variously stained paraffin sections of muscle prepared from affected calves were used to describe the lesions. A polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) test was developed and applied to affected calves, their sires, dams and other individuals.

RESULTS: The lesions were those of rhabdomyolysis of skeletal muscles and sub-sarcolemmal spaces in normal fibres. The PCR-RFLP test confirmed the expected mutation for phosphorylase deficiency of Charolais cattle in two affected calves. In addition, sires, dams and other closely-related individuals of four affected calves tested as heterozygous for the mutation. Other apparently unrelated animals also tested as heterozygous.

CONCLUSIONS: The diagnosis of myophosphorylase deficiency was confirmed. The PCR-RFLP test is suitable for use in controlling this recessively-inherited disorder as it can diagnose heterozygous individuals that are otherwise clinically normal.  相似文献   
8.
Canker stain, caused by the fungus Ceratocystis platani, is a destructive disease in Platanus spp. It has been recently proved that resistant accessions can be produced and grown in Europe. However, additional resistant genotypes are still needed in order to avoid the onset of virulent pathogen strains favoured by the selection pressures exerted by genetically homogeneous resistant plane tree plantings. In this study we present the results of two parallel experiments performed on 975 accessions of P. × acerifolia seedlings and P. × acerifolia clones derived by cutting propagation from mature trees grown in the urban environments. The selection process was based on inoculation with C. platani and yielded 13 accessions that showed different types of resistant reactions and survived in a stable manner thoughout the period of observation. Selected accessions were characterised by sequencing the rDNA-ITS region and by developing PCR procedures capable of detecting P. orientalis and P. occidentalis LEAFY homoeologues. These molecular analyses enabled us to confirm the identification of the species, its hybrid origin and to assess an evident genetic variability among the accessions, which therefore have to be considered as different genotypes. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
9.

Purpose  

The objective of this work was to assess the effect of severe drought conditions on the characteristics of semiarid soil humic acids (HAs) as well as the effect of organic amendment on such changes.  相似文献   
10.
为了探寻不同发育期朝鲜球坚蚧的有效防治新措施,根据朝鲜球坚蚧不同发育阶段的形态特征和生物学习性,对不同龄期的若虫采取刮皮涂干、树干注射和常规喷雾等措施进行防治.试验结果表明;在施药方法上,刮皮涂干和常规喷雾是最为适用的;在药效方面,在1龄若虫期喷雾施用的几种药剂中醋盐合剂对1龄若虫的喷洒防效达到了90%以上.通过施用脱叶剂处理叶片的方法来防治2龄若虫,试验所设3种浓度的脱叶剂均能间接起到防治作用,其效果均达到了95%以上.在3龄若虫期喷雾施用的几种药剂中95%酒精合剂的喷洒防效达到了90%以上.涂干防治3龄若虫期供试的几种药剂中,20%吡虫啉可溶性液剂1∶10的稀释液防效达到了90%以上.  相似文献   
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