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61.
Silvia Rossi Walter Bertazzolo Saverio Paltrinieri Alessia Giordano 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2008,37(4):422-428
Background: In routine canine medicine, anticoagulated blood is often the only sample sent to laboratories for diagnostic purposes. This hampers the interpretation of protein electrophoretic tracings because plasma contains fibrinogen, which migrates in the β–γ region. In human medicine, fibrinogen can be precipitated from plasma using ethanol. Objectives: The purpose of this study was to assess ethanol precipitation as a method for removing fibrinogen from canine plasma so as to facilitate the interpretation of electorphoresis results. Methods: Blood samples collected from 40 dogs were divided into plain tubes and tubes containing EDTA (n=20) or lithium–heparin (n=20). An aliquot of plasma from each sample was incubated with ethanol at a final concentration of 100 mL/L. Cellulose acetate electrophoresis was then performed on serum, plasma, and plasma treated with ethanol. To verify the efficiency of ethanol treatment, fibrinogen was added to 5 canine serum samples at final concentrations of 2.5, 5.0, and 10.0 g/L, and electrophoresis was performed before and after ethanol treatment. Results: Visual analysis of electrophoretograms from ethanol‐treated samples confirmed the disappearance of the fibrinogen peak from the β2‐globulin region. Treatment with ethanol caused a significant decrease in the percentage of β2‐globulins and a significant increase in the percentage of α2‐globulins. Absolute values of most electrophoretic fractions were significantly decreased in ethanol‐treated plasma compared with serum. Conclusions: Ethanol treatment successfully removed fibrinogen from canine plasma and normalized electrophoretic profiles, but probably also precipitated proteins other than fibrinogen. Ethanol treatment is recommended to facilitate visual identification of abnormal monoclonal peaks, but not for determining absolute protein concentrations in electrophoretic fractions. 相似文献
62.
猪乳中一组高分子量蛋白的多态性及其与繁殖性能关系的研究 总被引:10,自引:1,他引:9
采用十二烷基硫酸钠 聚丙烯酰胺凝胶不连续垂直板电泳 (SDS PAGE)对 16 2头二花脸母猪乳中一组高分子量蛋白质 (HMWP)进行了检测 ,计算了该位点的基因型频率、等位基因频率和遗传多样性指数等 ,并运用线性模型统计方法分析了该位点的不同基因型与母猪繁殖性能的关系。结果表明 ,在二花脸猪种群 ,乳中HMWP存在B(M :11480 0± 40 0 )和D(M :10 140 0± 6 0 0 )两种带 ,分别受二个等位基因HB 和HD 控制。BB、BD和DD三种基因型频率分别为 0 6 6 6 7、0 2 716和 0 0 6 17,两个等位基因HB 和HD 频率分别为 0 80 2 5和 0 1975 ,遗传多样性指数为0 3170。在三种HMWP基因型中 ,不同基因型母猪的繁殖性能在活仔数和窝重上存在着显著差异 (P <0 0 5 ) ,但在初生仔猪个体重和 2 0日龄窝重上未达到显著水平 (P >0 0 5 )。 相似文献
63.
64.
Six stability statistics: (bi, s2di, , , and ) were estimated for maize, wheat and sorghum in different environments by using three statistical models. The significant linear portion of genotype × environment interaction for maize indicates different hybrids responded differently to environments, whereas the non-significant genotype × environment interaction (linear) were found for wheat and sorghum suggest that all genotypes responded similarly as the environments change. However, the highly significant pooled deviations (deviation from regression) for all three crops make yield predictions from the model less reliable. When regression coefficients (bi) were non-significant, s2di, became an important statistic in estimating stability. It appears that the regression coefficient, bi, was best used to estimate genotypic adaptability, whereas s2di, for stability. Maize and sorghum had negative correlations between the mean yield and stability statistics, s2di, , and , suggesting that high yield and stability are not mutually exclusive in the range of environments used in this study; however, such correlations did not occur in wheat. Thus, maize and sorghum hybrids with high yield potential and high stability could be identified and selected. Correlations between mean yield and bi, or , were positive and significant for maize and sorghum but were non-significant for wheat, indicating that such relationships may be species specific. Under a given set of testing environments, the stability ranking associated with each maize hybrid is correlated to and depends on other hybrids included in the analysis. 相似文献
65.
66.
Esther S Rubin Walter M Boyce Chris J StermerSteven G Torres 《Biological conservation》2002,104(2):251-263
To further understand the impact of urban development on wildlife populations, we examined habitat use and selection by female bighorn sheep Ovis canadensis in two endangered subpopulations near a metropolitan area in southern California. One subpopulation, which had previously been found to have low reproductive success, selected urban environments while the other did not use urban areas. In the subpopulation that used urban areas, females had smaller core activity areas and selected lower elevations and gentler slopes. These females used urban sources of water but a clear relationship between levels of urban use and periods of increased water need was not evident. Diet quality was higher among females that selected urban areas, and this increase was correlated with the level of urban use. Thus, optimal foraging behavior may have contributed to the selection of urban areas. Urban use was lowest during peak months of parturition, suggesting that reproductive strategies may also have influenced temporal patterns of urban use. Although urban areas provided bighorn sheep with forage and water resources, the use of these areas may have substantial costs. For example, females using urban areas had internal parasites that were not found elsewhere in the Peninsular Ranges. 相似文献
67.
Detlef Deumlich Roger Funk Monika Frielinghaus Walter‐Alexander Schmidt Olaf Nitzsche 《植物养料与土壤学杂志》2006,169(3):370-381
Present research in Germany on water, wind, and tillage erosion is examined. Existing soil‐protection strategies, laws, and guidelines are outlined. These are the result of extensive scientific investigations and the adoption of existing international knowledge. The most common methodologies currently used in Germany are reviewed. They allow an estimation of the water‐ and wind‐erosion risks as well as methods for their reduction. The results enable an aim‐orientated, site‐specific, risk‐adequate approach to implementing control measures in an easily understood framework. The most important remaining research problems are explained. 相似文献
68.
Quantifying the most important mechanisms of acid buffering in carbonate-free soils From the release of cations from the soil matrix during pH-stat-titrations, characteristic values for assessing buffer rates were derived separately for single elements. Recorded buffer reactions became almost exclusively apparent in the release of Al and Fe, however the contribution of Fe to the total turnover only amounted to 1–3%. The release of each element and of DOC in the course of time was due to the overlapping of two first-order reactions, respectively. In the fast initial reaction all measured elements were released at nearly the same velocity, whereas in the 2nd, slower reaction the rate of Al-release corresponded to that of DOC but was at least seven times higher than that of Fe. Correlations between the maxima of release and soil chemical properties revealed a dominating contribution of organically bound Al (Alp) to proton buffering. It is assumed that also the amount of Fe released is originating in organic complexes. 相似文献
69.
We explored the extent of interspecific hybridisation between alien and native plant species in Germany with a special focus on the potential threat for native biodiversity. In total we listed 134 hybrids which are interpreted as products of hybridisation between 81 alien and 109 native plant species (including 13 archeophytes) that occur in Germany. Seventy-five of these hybrids have been recorded in Germany, while the remaining 59 hybrids have not been detected in Germany yet, although both parental species currently occur in Germany. Interspecific hybridisation between abundant alien and rare native species can threaten populations of the native species through outbreeding depression and/or through high rates of gene flow swamping native populations. We identified 37 threatened native plant species which hybridise with aliens. Seventeen of these threatened plant species may suffer from outbreeding depression when hybridising with a more abundant alien invader (minority disadvantage). Using hybrid abundance as an indicator of hybrid fitness we argue that introgression of alien genes may affect the gene pool of eight threatened native plant species. Consequently, hybridisation with aliens has to be considered as an additional risk potentially leading to a loss of biodiversity and should be included in the repertoire of causes for rare species extinction in German Red Lists of threatened plant species. 相似文献
70.
Two plant species, tomato (Lycopersicon esculentum Mill.) and bitter gourd (Momordica charantia), were used for in‐depth studies on the dynamics of silicon (Si) uptake and translocation to the shoots and compartmentation of Si in the roots. The experiments were conducted under controlled environmental conditions in nutrient solutions, which were partly amended with 1 mM Si in the form of silicic acid. At harvest, xylem exudates were collected, and Si concentrations and biomass of roots and shoots were determined. Mass flow of Si was calculated based on the Si concentration of the nutrient solution and transpiration determined in a parallel experiment. Plant roots were subjected to a fractionated Si analysis, allowing attributing Si to different root compartments. Silicon concentrations in the roots compared to the shoots were higher in tomato but lower in bitter gourd. A more ready translocation from the roots to the shoots in bitter gourd was in agreement with Si concentrations in the xylem exudates which were higher than in the external solution. In tomato, the xylem‐sap Si concentration was lower than in the nutrient solution. Calculated Si mass flow to the root exceeded Si uptake in tomato, which was consistent with the measured accumulation of Si in the root water‐free space (WFS). In contrast, Si concentration in the root WFS was lower than in the nutrient solution in bitter gourd, reflecting the calculated Si depletion at the root surface based on the comparison of Si mass flow and Si uptake. Within the roots, more than 80% of the total Si was located in the cell wall and less than 10% in the cytoplasmic fractions in tomato. In bitter gourd, between 60% and 70% of the total root Si was attributed to the cell‐wall fraction whereas the proportion of the cytoplasmic fraction reached more than 30%. Our results clearly confirm that tomato belongs to the Si excluders and bitter gourd to the Si‐accumulator plant species for which high Si concentrations in the cytoplasmic root fraction appear to be characteristic. 相似文献