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AIM:To investigate the role of expression of peroxisome proliferator-activated receptor α(PPAR α) in pathogenesis of rat fatty liver.METHODS:The rats were treated with a low dose of carbon terachloride (CCl4) and fed a high fat diet to produce fatty liver. We determined the concentrations of triglyceride (TG), total cholesterol (TC), free fatty acid (FFA) in liver and the alanine aminotransferase (ALT) activity, tumor necrosis factor-α (TNF-α), FFA in serum and the degree of hepatocytic steatosis. Total RNA of liver was extracted, and the expression of PPAR α were analyzed by semi-quantitative RT-PCR method.RESULTS:In model group, the hepatocytic PPAR α mRNA expression decreased to 0.41±0.28, compared to 1.41±0.29 in the control group (P<0.01). The contents of TG, TC, FFA in model rat liver were (1.88±0.20) mmol·L-1, (11.03±1.12) mmol·L-1 and (1 260.38±151.27) μmol·L-1, respectively, compared to (0.53±0.10) mmol·L-1, (1.25±0.25) mmol·L-1 and (334.30±27.09) μmol·L-1 in the control group (P<0.01). The activity of ALT, concentrations of TNF-α and FFA in serum were also increased remarkably in model group.CONCLUSION:Oxidation of fatty acid and utilization of lipids in liver are affected by reducing the expression of PPAR α, which result lipid accumulation in liver. 相似文献
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HUANG Ping ZHANG Jia-bao XIN Xiu-li ZHU An-ning ZHANG Cong-zhi MA Dong-hao ZHU Qiang-gen YANG Shan WU Sheng-jun 《中国农业科学(英文版)》2015,(1)
Cropland productivity has been signiifcantly impacted by soil acidiifcation resulted from nitrogen (N) fertilization, especialy as a result of excess ammoniacal N input. With decades’ intensive agricul... 相似文献
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Annual C input to soil is a major factor affecting soil organic carbon (SOC) dynamics. However different types of C-sources can have different behaviour, in relation to their chemical characteristics and how they interact with soil. Root-derived C, in particular, should be more efficient than other organic materials as a result of the physicochemical and biological characteristics of the surrounding environment, leading to a reduction in the C decomposition rate.To test this hypothesis, we considered a long-term experiment underway in Northern Italy since 1962, comparing permanent meadow and 6 different crop rotations over a wide range of nutrient inputs, in both organic and inorganic forms. C inputs from amendments were measured and those from crops were calculated using allometric functions and crop and residues yields. The time evolution of SOC was studied through a single-pool, first-order kinetic model, allowing the estimation of humification coefficients for residues, roots, farmyard manure and cattle slurries.The highest value of the humification coefficient was estimated for farmyard manure, which confirmed its high efficiency in stabilising SOC content. Root C presented a humification coefficient 1.9 times higher than above-ground plant materials while slurries were intermediate, with a humification coefficient roughly half that of farmyard manure and even lower that of roots.The quality of C input thus seems of fundamental importance for evaluating the sustainability of different cropping systems in terms of SOC dynamics. 相似文献
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Monitoring the dynamics of soil salinization is of great importance for agricultural production. This study selected Yucheng County, a typical county on the Huang-Huai-Hai Plain (HHHP) of China, as the study area and evaluated the spatial and temporal variation of soil salinization. Three methods, consisting of principal component analysis (PCA) transformation, tasseled cap (TC) transformation, and optimal band combination (OBC), were used to extract information from an early Landsat multispectral scanner (MSS) image from 1984, and their advantages were compared. In addition, OBC was used on a thematic mapper (TM) image from 2009. An iteratively self-organizing data analysis algorithm was used together with prior knowledge of likely classifications to interpret the MSS and TM images for data classification. Finally, a transfer matrix method was used to assess the spatial and temporal variability of soil salinization and analyze the driving factors of soil salinization. Compared to PCA transformation and OBC, TC transformation was a more effective method for extracting soil salinization information from the MSS sensor. The results indicate that a soil area of approximately 298 km2 was affected by salinity in 1984 in Yucheng County, of which 5.40%, 11.96%, and 12.75% were classified as being subject to slight, moderate, and severe salinization, respectively. In 2009, the saline area was reduced to only 146 km2, of which 10.70% and 3.75% were characterized by slight to moderate salinization and no severe salinization, respectively. The saline land decreased at an average rate of 6 km2 per year. This decrease was probably a result of lower groundwater depth, increased organic fertilizer or crop straw in soil, changed land use type, and increased vegetation coverage. 相似文献
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The effects of inoculation with two AM fungi (M1, Glomus caledonium; M2, Glomus spp. and Acaulospora spp.) and a fungivorous nematode Aphelenchoides sp. on growth and arsenic (As) uptake of Nicotiana tabacum L. were investigated in soils contaminated with a range of As. The reproduction of Aphelenchoides sp. was triggered by the co-inoculation of AM fungi regardless of AM fungal isolates and As levels. Stimulative effects of Aphelenchoides sp. on the development of mycorrhiza, slightly different between two AM fungi, were found particularly at the lowest As level. Irrespective of mycorrhizal inoculi, increasing soil As level decreased plant growth, but increased plant As uptake. Co-inoculation of AM fungi and Aphelenchoides sp. led plants to achieving further growth and greater As accumulation at the lowest As level. Results showed that the interactions between AM fungi and fungivorous nematodes were important in plant As tolerance and phytoextraction at low level As-polluted soil. 相似文献
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利用CT扫描技术确定土壤大孔隙分形维数 总被引:16,自引:0,他引:16
土壤大孔隙的大小、形状和分布对水及溶质在土壤中的运移有着深刻影响,由于土壤大孔隙的分布呈现分形规律,根据采用CT扫描法得到的原状土柱各断面图像,采用计盒维数法计算出各断面土壤大孔隙的分形维数。 相似文献