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Water, Air, & Soil Pollution - Elevated radium (Ra) concentrations have been observed in aquifers with high naturally occurring salinity. The flux of radon (Rn) gas from the decay of Ra out of...  相似文献   
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Atopic dermatitis (AD) is a chronic or chronically relapsing human and canine skin disease that is known to affect the quality of life (QoL) of affected individuals. Several studies have been conducted to develop disease-specific questionnaires and assess QoL in parents of children with AD and in the children themselves. The severity of canine AD is however currently evaluated using only clinical and pruritus scores. Measurement of the QoL of affected dogs and their owners could therefore provide a new tool for assessing disease severity and treatment efficacy. Ninety-eight owners of AD-affected dogs were asked to complete two questionnaires aiming to evaluate the QoL of affected dogs and their owners on one hand and the relationship between them and their dog on the other hand. Statistical analyses were carried out in order to assess the validity of the questionnaires and to select relevant questions for future studies. These analyses resulted in the selection of 13 questions that could be used in further studies aiming at determining the QoL of affected animals and their owners.  相似文献   
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The IgE specific Fc-? receptor test is widely used for serological evaluation of allergic canine patients. Aim of the study was to evaluate intra- and interlaboratory variability in three independent laboratories. Duplicate serum aliquots from 15 atopic dogs were submitted simultaneously to 3 laboratories (LA, LB, LC), which subsequently performed the test in a blinded fashion. LA and LC analysed sera for 35 allergens and expressed the results as optical density units (OD), while LB analysed 15 allergens and provided reaction grades (RG). Results were compared with three factorial ANOVA. Intralaboratory variability was evaluated by calculating the dispersion factor for data of LA and LC and standard deviation (SD) for LB. Correlation coefficients (r) were used to evaluate interlaboratory variability. Depending on the allergens, intralaboratory dispersion factor for LA and LC varied from 1.15 to 6.63 and 1.19 to 6.17, respectively. In LB the SD varied between 0 and 0.6 RG. Regarding interlaboratory variability, correlation of OD values between LA and LC was excellent (r > 0.8, p < 0.001) for 13 of 35 allergens. There was a significant difference in OD results for 9 allergens. The results were significantly correlated (r > 0.8, p < 0.001) for all except 3 allergens (Dermatophagoides pteronyssinus, mixed grasses, nettle). As far as negative/positive results were concerned, intralaboratory differences were 3.14% and interlaboratory differences were 4.76%.  相似文献   
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将印度梨形孢真菌(Piriformospora indica)接种于受不同干旱胁迫花生幼苗根部,研究接种该真菌对花生抗旱性的影响.试验设置3个处理,分别是:接菌+干旱胁迫处理、未接菌+干旱胁迫处理、未接菌+未干旱胁迫处理(CK).试验结果表明:接菌+干旱处理后的花生主根长、根鲜重、根干重、茎鲜重、茎干重、叶鲜重、叶干重、叶绿素含量(SPAD值)等农艺性状表现分别为14.96 cm、0.64g、0.08 g、1.48 g、0.20 g、1.61 g、0.29 g、42.63.与未接菌+干旱处理相比均显著增加,增幅分别为26.8%、25.50%、60%、15.63%、17.65%、15.59%、26.09%、7.43%.与对照相比,在主根长、根鲜重、根干重、茎干重、叶干重、叶绿素含量(SPAD值)等性状方面均没有显著性变化.以上结果说明:在干旱胁迫条件下,接种印度梨形孢真菌能够维持花生正常生长,使得花生从植株外部形态上表现出较强的抗旱性.  相似文献   
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Bioassays were conducted in Mauritania to determine the toxicity of botanical insecticides from the tree Melia volkensii Gürke (Meliaceae) to ladybird predators (Coleoptera: Coccinellidae) of the date palm scale, Parlatoria planchardi Targ. (Homoptera: Diaspididae). M. volkensii seed extract was formulated in neem oil or a mixture of neem and maize oil. Three preparations were tested on Chilocorus bipustulatus L. var. iranensis, an introduced species, and one on the indigenous Pharoscymnus anchorago F., a species already used in previous bioassays. Fourth instar larvae were exposed for 2 days to treated scale-infested date palm leaves. The botanical insecticides were toxic to C. bipustulatus. Median lethal application rates (LR50s) were close to the recommended application rate of 1 l/ha. In contrast, P. anchorago showed no increased mortality at this rate. Hazard quotients (application rate divided by the LR50) were generally less than 2, suggesting a low risk for both species. However, risk mitigation measures are recommended when using oil formulations because the threshold value for C. bipustulatus, the more susceptible of the two ladybird species, would be exceeded at higher dose rates or when conducting multiple applications. Sublethal effects included an extension of the larval stage and morphogenetic defects. These effects were again more pronounced in C. bipustulatus than in P. anchorago.  相似文献   
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Background: In veterinary medicine, there is increasing interest in measuring C‐reactive protein (CRP) as a tool for diagnosis and monitoring of inflammatory diseases. Reported CRP concentrations for healthy dogs have ranged from 0 to 8.9 mg/L. Objectives: The aims of this study were to evaluate a canine‐specific point‐of‐care (POC) lateral flow immunoassay for qualitative CRP measurement in healthy and diseased dogs and to compare results with those obtained by a quantitative ELISA. Methods: Blood samples from 73 client‐owned dogs were available for testing: 16 healthy dogs and 57 dogs with a variety of infectious, inflammatory, or neoplastic diseases. CRP was measured in heparinized whole blood samples and serum with the TECOmedical Dog CRP‐visual POC test. A red line develops in the POC device if CRP is ≥5 mg/L, and results are scored as negative or positive. An ELISA validated previously for canine serum was used as the reference method. Results: For all dogs, serum CRP concentrations measured by the ELISA ranged from 0.1 to ≥350 mg/L (median=38 mg/L). Percentages of the CRP POC test results that agreed with the ELISA results were 98.6% for whole blood and 97.3% for serum samples. For serum samples, sensitivity of the POC test was 96.4% and specificity was 81.3%. For whole blood, sensitivity was 94.7% and specificity was 93.8%. Conclusions: The POC test had very good agreement with the ELISA test and had high sensitivity and specificity; therefore, it can be used as a qualitative test to screen for increases in CRP concentrations.  相似文献   
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Sediment and porewater samples from an enclosed bay receiving stormwater discharge (Skutviken) near the centre of Lule?, northern Sweden were analysed for major and trace elements and 16 polycyclic aromatic hydrocarbons (PAHs). Among the studied metals Cd, Cu, Pb and Zn were enriched at Skutviken. Also, the PAH content was enriched, in particular for phenantrene, anthracene, fluoranthene and pyrene which are regarded as common constituents in stormwater. The use of trace metal ratios provided indications about pollutant sources for the sediment. Cs-137 dating was used to determine historical changes in metal and PAH fixation in the sediment. The bay Skutviken is enclosed through the construction of a road bank since 1962. The enclosure led to reduced water circulation in the bay that promotes the occurrence of anoxic conditions with sulphate reduction within the bay. As a consequence of these conditions, metals are trapped in the sediments as sulphides. This study suggests that enclosed bays with restricted water circulation may be efficient traps for urban pollutants, reducing the present-day input of pollutants to the sea. In areas with postglacial land uplift, where such bays are common, bay sediments are a potential future source of pollutants when uplift results in erosion and oxidation of the sediments.  相似文献   
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