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This study compares the detection of faecal contamination indicators in irrigation water (25 samples) by two analytical techniques: multiple tube fermentation method (MPN) and Colilert/Enterolert Quanti-Tray system. Our aim was to investigate variations in the test results and determine whether variations could be related to 1) the interval of time between the sample collection and analysis and 2) the manual labour of the operator. Each water sample was analysed at specific intervals of time from the sample collection within 24 h and by three different operators. Statistical analysis was employed to evaluate the results. We have proved that the indices obtained with the multiple tube fermentation method show greater variation than the values obtained with the Colilert and Enterolert systems. Furthermore, some samples, analysed by the MPN method, showed different values, but not statistically significant, in relation to the intervals of time between the sample collection and analysis and in relation to the data obtained by the manual labour of the operators. Values for the same sample varied in respect to legislative limits. The Colilert and Enterolert systems for the detection of indicator bacteria could be a substitute for the standard methods. This procedure could be used for monitoring the quality of irrigation water.  相似文献   
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Hydrogen peroxide (H2O2) localization and roles of peroxidases, malondialdehyde and reduced glutathione were compared in leaves of apricot (Prunus armeniaca) plants asymptomatic, European Stone Fruits Yellows (ESFY)-symptomatic and recovered. Nested PCR analysis revealed that Candidatus Phytoplasma prunorum, is present in asymptomatic, symptomatic and recovered apricot trees, confirming previous observations on this species, in which recovery does not seem to be related to the disappearance of phytoplasma from the plant.H2O2was detected cytochemically by its reaction with cerium chloride, which produces electron-dense deposits of cerium perhydroxides. H2O2was present in the plasmalemma of the phloem cells of recovered apricot plant leaves, but not in the asymptomatic or symptomatic material. Furthermore, by labelling apricot leaf tissues with diaminobenzidine DAB, no differences were found in the localization of peroxidases.Protein content in asymptomatic, symptomatic and recovered leaves was not significantly different from one another. In contrast, guaiacol peroxidase activity had the following trend: symptomatic > recovered > asymptomatic, whereas reduced glutathione content followed the opposite trend: asymptomatic > recovered > symptomatic. Moreover, no differences were observed in malondialdehyde concentrations between asymptomatic, symptomatic and recovered leaves. The overall results suggest that H2O2 and related metabolites and enzymes appear to be involved in lessening both pathogen virulence and disease symptom expression in ESFY-infected apricot plants.  相似文献   
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OBJECTIVE: To evaluate the effectiveness of a herniorrhaphy technique, using an autogenous fascia lata graft (FLG) for perineal hernia (PH) repair in dogs. STUDY DESIGN: Prospective clinical study. ANIMALS: Twelve dogs with PH. METHOD: PHs were repaired with FLG harvested from the dog's ipsilateral thigh and sutured directly into the perineal defect. Correction of associated conditions, and castration were performed. Surgical time, pain, inflammation, pattern of defecation, lameness, hospitalization time, postoperative complications, and owner satisfaction were recorded. Histopathologic examination was performed in 1 dog euthanatized 10 months after repair. RESULTS: Hernia did not recur (mean follow-up, 5.8 months). Lameness was the most frequent minor complication, and was resolved within a few days. Transient rectal prolapse occurred in 2 dogs with bilateral PH. The mean (+/-SD) hospitalization was 1.8+/-0.9 days, and the surgical time was 76.5+/-9.8 minutes. Histopathologic examination in 1 dog revealed perfect integration of FLG into adjacent tissues without substantial tissue reaction. CONCLUSIONS: FLG reconstruction of PH is a simple, effective method of treatment. CLINICAL RELEVANCE: FLG can be used without major complications for primary repair of PH, as an augmentation procedure when the internal obturator muscle is thin or friable, or when herniation has recurred after another repair technique.  相似文献   
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Global mineralogical mapping of Mars by the Observatoire pour la Mineralogie, l'Eau, les Glaces et l'Activité (OMEGA) instrument on the European Space Agency's Mars Express spacecraft provides new information on Mars' geological and climatic history. Phyllosilicates formed by aqueous alteration very early in the planet's history (the "phyllocian" era) are found in the oldest terrains; sulfates were formed in a second era (the "theiikian" era) in an acidic environment. Beginning about 3.5 billion years ago, the last era (the "siderikian") is dominated by the formation of anhydrous ferric oxides in a slow superficial weathering, without liquid water playing a major role across the planet.  相似文献   
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Ocular lesions associated with Trypanosoma spp. infection have been described in man and many animal species. However, loss of vision has not been demonstrated in humans presenting Chagas disease or in animals affected by different trypanosome species. In order to assess the possible ocular disorders caused by Trypanosoma evansi infection, six goats were inoculated with 1 x 10(5) T. evansi and maintained for 12 months and four goats were used as control. The inoculated animals became positive at serological and parasitological tests at 1-month post-inoculation and showed a subclinical course of the disease. Unilateral superficial corneal ulceration and retinochoroiditis were observed in two inoculated animals. Data from ocular neurologic examination and electroretinography showed no significant differences between inoculated and non-inoculated goats. It could be concluded that Trypanosoma evansi can produce ocular lesion but without apparent loss of vision in goats.  相似文献   
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Objective-To determine glycohistochemical characteristics of enzootic nasal tumors (ENTs) of sheep, compare results for ENT with those of histologically normal nasal mucosa of sheep, and identify the histologic origin of ENT. Sample-ENT and nasal mucosa samples obtained from cadavers of 5 adult Lacaune sheep with ENT and 5 Lacaune sheep unaffected by ENT, respectively. Procedures-Samples of ENT and nasal mucosa were collected from cadavers of sheep and sectioned. Conventional and lectin histochemical analyses were used to identify glycoconjugates in tissue sections on the basis of their principal chemical groups and principal terminal or internal oligosaccharidic glucidic residues, respectively. Results-ENTs had papillary and tubular portions. Cells in the papillary portion of ENTs had secretion and surface glycoconjugates, which included sulfated glycosaminoglycans and neutral and sialilated glycoproteins. Cells in the tubular portion of ENTs had surface glycoconjugates, which included neutral and sialilated glycoproteins. Both portions of ENTs had C(4)-acetylated sialoderivatives that were not detected in sections of histologically normal nasal mucosa. Conclusions and Clinical Relevance-The papillary portion of ENTs in sheep may originate from respiratory glands and goblet cells. The tubular portion of ENTs in sheep may originate from olfactory glands. Presence of C(4)-acetylated sialoderivatives in cells of ENTs could confer resistance against pathogens to those cells.  相似文献   
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MicroRNAs (miRNAs) are a family of regulatory molecules involved in many physiological processes, including activation of cells of the immune system. This study investigated the effect of Escherichia coli lipopolysaccharide (LPS) and Staphylococcus aureus enterotoxin B (SEB) on the expression of five miRNAs involved in the inflammatory response, including miR-9, miR-125 b, miR-155, miR-146 a and miR-223, in bovine CD14(+) cells (monocytes). Incubation of monocytes with SEB induced down-regulation of miR-155, miR-223 and miR-125 b, but not the anti-inflammatory miRNA miR-146 a. Conversely, incubation with LPS upregulated both miR-155 and miR-146 a. In vitro incubation of isolated CD14(+) bovine monocytes with LPS and SEB elicited different and opposite expression of miRNAs reportedly involved in inflammatory reactions.  相似文献   
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