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31.
A pot culture experiment was conducted to investigate the effects of amorphous iron-(hydr)oxide (Am-FeOH) amendments on arsenic (As) availability and its uptake by rice ( Oryza sativa L. cv. BR28) irrigated with As-contaminated water. A rhizobag system was established using 3.5 L plastic pots, each containing one central compartment for plant growth, a middle compartment and an outside compartment. Three levels of laboratory-synthesized Am-FeOH (0, 0.1 and 0.5% w/w) were used to amend samples of the As-free sandy loam paddy soil placed into each compartment of the rhizobag system. The soils were submerged with a solution containing 5 mg L−1 As(V). Two-week-old rice seedlings were planted in the central compartments and cultured for 9 weeks under greenhouse conditions. The addition of 0.1% Am-FeOH to the soil irrigated with As-contaminated water improved plant growth, reduced the As concentration in the plants and enhanced Fe-plaque formation on the root surfaces. Analysis of soil solution samples collected during the experiment revealed higher pH levels and lower redox potentials in the soils amended with Am-FeOH at the onset of soil submergence, but later the soil solution collected from the 0.1% Am-FeOH treatment was slightly acidic and more oxidized than the solution from the 0% treatment. This indicated active functioning of the roots in the soil treated with 0.1% Am-FeOH. The concentrations of As(III) in the soil solution collected from the central compartment were significantly reduced by the Am-FeOH amendments, whereas in the soil treated with 0% Fe, As(III) accumulated in the rhizosphere, particularly during the late-cultivation period. The improvement in plant growth and reduction in As uptake by plants growing in the Am-FeOH treated soil could be attributed to the reduction of available As in the soil solution, mainly as a result of the binding of As to the Fe-plaque on the root surfaces.  相似文献   
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Sustained narrow-QRS tachycardia of three months duration and left ventricular systolic dysfunction were identified in a fifteen-year-old Quarter Horse. No underlying cause for the tachyarrhythmia was found and no predisposing structural cardiac lesions were evident by echocardiography. Intravenous diltiazem and lidocaine were administered without achieving successful conversion of the arrhythmia. Oral quinidine therapy converted the tachyarrhythmia to sinus rhythm. Ventricular systolic dysfunction and chamber dilatation subsequently resolved. As with other species, echocardiographic features of dilated cardiomyopathy can be tachycardia-induced and may resolve following successful control of heart rate and rhythm.  相似文献   
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In the search for new functional ingredients with potential use in the food industry, extracts of unknown species of microalgae, such as Phormidium species have been studied. Three solvents of different polarities (i.e., hexane, ethanol, and water) have been used to obtain pressurized liquid extracts with different compositions. Moreover, extractions were performed at four different extraction temperatures (50, 100, 150, and 200 degrees C) with 20 min as extraction time. Antioxidant activity of the extracts has been measured by the TEAC assay. In general, hexane and ethanol extracts showed a higher antioxidant capacity that was mainly attributed to carotenoid compounds, as the TEAC value trend seems to be similar to the carotenoid content of the extracts. On the other hand, the high antioxidant activity of the 200 degrees C water extracts is likely related to the presence of Maillard reaction compounds produced by thermal degradation of the sample. beta-Carotene, lutein, violaxanthin, and neoxanthin were identified in 150 degrees C ethanol extracts. Four different microbial species ( Escherichia coli, Staphylococcus aureus, Candida albicans, and Aspergillus niger) were used to screen the potential antimicrobial activity of the Phormidium sp. extracts. The most sensitive microorganism was the yeast, C. albicans, whereas the fungus, A. niger, was the most resistant. In general, no drastic differences were found for solvents and temperatures tested, showing a very diverse nature of the compounds responsible for the antimicrobial activity of these microalgae. In ethanol extracts, antimicrobial activity could be mainly attributed to the presence of terpenes (i.e., beta-ionone, neophytadiene) and fatty acids (i.e., palmitoleic and linoleic acids) in the samples. Toxicity studies carried out with the extracts evaluated in the present work showed a cellular toxicity lower than those of other cyanobacteria such as Spirulina plantensis.  相似文献   
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Histopathological study was made of 12 Merino sheep - five splenectomized and seven intact - experimentally infected with Babesia ovis. Non-purulent encephalitis; initially exudative and subsequently interstitial pneumonia; pericarditis, myocarditis and haemorrhagic endocarditis; centrilobular necrotic hepatitis; hyperplasia of the lymphoreticular system; necrosis and vascular changes in adrenal glands were observed. The kidney was the most severely affected organ, exhibiting acute tubular necrosis typical of kidney shock syndrome. The lesions observed were suggestive of hypovolemic shock culminating in haemorrhagic diathesis owing to consumptive coagulopathy. Additionally, the massive release of catabolites from lysis and necrosis apparently produced endotoxic shock.  相似文献   
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A study has been carried out with the aim to determine possible interactions between Ascaris suum and Metastrongylus apri under experimentally infected pigs. Twenty-eight Iberian pigs were allocated into four groups. Group 1 was inoculated with 5000 infective A. suum eggs; group 2 received concurrently 5000 infective A. suum eggs and 5000 infective M. apri larvae; group 3 received 5000 infective M. apri larvae; group 4 served as uninfected controls. In each group, pigs were necropsied on day 7 (n = 4) and day 28 (n = 3) post-infection (p.i.). Pigs with single M. apri infections showed earlier and more severe respiratory symptoms compared to pigs with mixed infection, while no clinical signs were observed in pigs single infected with A. suum. Mean burdens of immature A. suum and immature and adult M. apri were reduced in pigs with concomitant infection both on day 7 and 28 p.i., respectively. In contrast, the number of white spots was significantly increased on day 7 in pigs with mixed infection. In addition, pigs of group 1 showed the highest eosinophil levels in blood compared to pigs in groups 2 (intermediate levels) and 3 (moderate levels). The results suggest an antagonistic interaction between A. suum and M. apri in concomitantly infected pigs.  相似文献   
36.
The immunodetection of local Ascaris suum antigens and local and systemic antibodies were analysed in pigs reinfected with eggs or immunized with the 14, 42 and 97 kilodalton (kDa) fractions from A. suum. Twenty-one Iberian pigs were divided in 7 groups of 3 pigs. Groups 1 and 2 were uninfected and challenge control groups, respectively. Groups 3 and 4 were infected weekly with increasing doses of A. suum eggs and Group 4 was additionally treated with pyrantel pamoate. Groups 5, 6 and 7 were immunised with the 14, 42 or 97 kDa fractions from adult worms, respectively. Groups 2-7 were challenged with 10,000 infective eggs. Animals of Groups 3 and 4 showed a pulmonary granulomatous reaction with moderate number of eosinophils and leukocytes, while Groups 5-7 presented higher number of cells, especially in animals immunized with the 42 kDa fraction. These immunized groups presented abundant deposition of Ascaris body fluid (BF) and body wall (BW) antigens as well as the 14 and 42 kDa fractions in the pulmonary and intestinal tissues, while lower deposition of antigens was observed in animals of Groups 3 and 4. The immunized pigs of Groups 5 and 6 showed the highest systemic IgG titres in serum and these antibodies were negatively correlated with the number of larvae recovered in the lungs, suggesting that the IgG response may have a protective function against the ascariosis. The highest concentrations of IgA-bearing cells were observed in animals of Groups 3 and 4 compared to the immunised pigs (Groups 5-7), suggesting that local IgA production may be involved in the protection against migrating larvae. The main localisations of IgA-bearing cells were the bronchial and peribronchial areas of lungs and the lamina propia of duodenum. Low numbers of local IgG-bearing cells were observed in all animals and no IgM-bearing cells were detected in the local tissues.  相似文献   
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OBJECTIVE: To describe geographical differences and time trends in the supply of the most important food components of the traditional Mediterranean diet. DESIGN: Food supply data collected from national food balance sheets for the period 1961-2001. SETTING: Selected Mediterranean countries: Spain, Italy, France, Greece, Algeria, Morocco, Tunisia and Turkey. RESULTS: Differences of almost 30-fold and five-fold were found in the supply of olive oil and fruits and vegetables, respectively, among the Mediterranean countries studied during the 1960s. A favourable increasing trend for the supply of fruit and vegetables was observed in most Mediterranean countries. However, an increase in the supply of meats and dairy products and a decrease in the supply of cereals and wine were observed in European Mediterranean countries from 1961 until 2001. Only in African and Asiatic Mediterranean countries were cereals the base of food supply. During the 1990s, Greece's food supply pattern was closest to the traditional Mediterranean diet, while Italy and Spain maintained a high availability of fruits, vegetables and olive oil, but were losing the other typical components. Among African and Asiatic Mediterranean countries, only Turkey presented a traditional Mediterranean dietary pattern except with respect to olive oil, the supply of which was very low. France showed a Western dietary pattern, with a high supply of animal products and a low supply of olive oil. CONCLUSIONS: Dietary supplies in the Mediterranean area were quite heterogeneous in the 1960s and have experienced a process of Westernization, especially in European Mediterranean countries.  相似文献   
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