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91.
Mango (Mangifera indica L.) and their components are commonly used in folk medicine for many curative effects. The protective effects of different concentrations of aqueous extract of Mangifera indica L. fruit (Mango Extract) (20, 50 and 100 μg/ml) and also gallic acid (100 μM) as a pure compound in the extract were examined against oxidative stress toxicity induced by cumene hydroperoxide (CHP) in isolated rat hepatocytes. The extracts and gallic acid (100 μM) protected the hepatocyte against all oxidative stress markers including cell lysis, ROS generation, lipid peroxidation, glutathione depletion, mitochondrial membrane potential decrease, lysosomal membrane oxidative damage and cellular proteolysis. Mango Extracts (20, 50 and 100 μg/ml) were more effective than gallic acid (100 μM) in protecting hepatocytes against CHP induced lipid peroxidation. On the other hand gallic acid (100 μM) acted more effective than Mango Extracts (20, 50 and 100 μg/ml) at preventing lysosomal membrane damage. In addition H2O2 scavenging effect of all extracts were determined in hepatocytes and compared with gallic acid (100 μM). There were no significance differences (P<0.05) between all plant extracts and gallic acid (100 μM) in H2O2 scavenging activity. These results suggest a hepatoprotective role for Mango Extract against liver injury associated with oxidative stress.  相似文献   
92.
93.
Taste disturbances following consumption of pine nuts, referred to as "pine mouth", have been reported by consumers in the United States and Europe. Nuts of Pinus armandii have been associated with pine mouth, and a diagnostic index (DI) measuring the content of Δ5-unsaturated fatty acids relative to that of their fatty acid precursors has been proposed for identifying nuts from this species. A 100 m SLB-IL 111 GC column was used to improve fatty acid separations, and 45 pine nut samples were analyzed, including pine mouth-associated samples. This study examined the use of a DI for the identification of mixtures of pine nut species and showed the limitation of morphological characteristics for species identification. DI values for many commercial samples did not match those of known reference species, indicating that the majority of pine nuts collected in the U.S. market, including those associated with pine mouth, are mixtures of nuts from different Pinus species.  相似文献   
94.
Ranked set sampling is a sampling approach that could lead to improved statistical inference when the actual measurement of the variable of interest is difficult or expensive to obtain but sampling units can be easily ordered by some means without actual quantification. In this paper, we consider the problem of bootstrapping an unbalanced ranked set sample (URSS) where the number of observations from each artificially created stratum can be unequal. We discuss resampling a URSS through transforming it into a balanced RSS and extending the existing algorithms. We propose two methods that are designed to obtain resamples from the given URSS. Algorithms are provided and several properties, including asymptotic normality of estimates, are discussed. The proposed methods are compared with the parametric bootstrap using Monte Carlo simulations for the problem of testing a hypothesis about the population mean.  相似文献   
95.
The consumption of solid feed is essential for successful transition from a pre-ruminant to a functional digestive tract. Lambs fed starter rations containing highly fermentable carbohydrates often experience dramatic changes in concentrations of rumen and blood metabolites. The optimal amount of roughage required in the diet of pre-ruminant animals is still unclear. The objective of this study was to determine the effect of feeding alfalfa hay on performance and rumen development in young Balouchi lambs. In a completely randomized design, 30 lambs were fed one of three experimental diets consisting of a control, without alfalfa hay (C), a diet containing 7.5% alfalfa hay (A1), and a diet containing 15% alfalfa hay (A2). Lambs fed A1 and A2 diets had lower dry matter intake during the pre-weaning period (P?P?=?0.02), but feed conversion ratio and average daily gain were not affected by feeding alfalfa hay. Concentration of beta-hydroxybutyric acid was higher in C compared with the A1 and A2 groups (P?P?=?0.04) and increased thickness of muscular layer (P?=?0.05). We concluded that including 15% alfalfa hay in the starter diet could reduce thickness of the keratinization layer and increase muscularity of rumen wall without adverse effects on growth and performance of newborn lambs.  相似文献   
96.
In 1931 Carpantier reported bovine TB (BTB) in Iranian cattle. Some eighty years on with a national test-and-slaughter programme in place for over four decades, the efforts to vanquish Mycobacterium bovis (M. bovis) infection in cattle have been in vain as the vast majority of the 30 Iranian provinces still have reports of BTB in their cattle herds every year. This paper reviews the present epidemiology of BTB in Iran and in the region and evaluates the success of government policy in controlling this disease.  相似文献   
97.
The inadequacy of most models to simulate crop growth and yield is due to complexity, difficulty to understand, and lack of input data. Therefore, several simple crop growth models are presented to reduce these failures. In this investigation, yield and aboveground dry matter (DMabove) of rapeseed were simulated by two logistic growth models that were based on days after planting (DAP) and growing degree days (GDD) under water salinity and deficit irrigation, in a 2-year experiment. Data of first and second year were used for calibration and validation of the model, respectively. The coefficients of logistic function were determined as a function of irrigation water salinity and sum of applied water and rainfall in spring of the first year. Results indicated that logistic function based on GDD-predicted DMabove during growing season more accurately than logistic function based on DAP. Furthermore, seed yield of rapeseed was estimated based on harvest index with a good accuracy. Therefore, logistic function based on GDD that is based on the cumulative heat units can be used for different weather conditions and planting dates to determine rapeseed DMabove and yield under water salinity and deficit irrigation.  相似文献   
98.
Deficiencies of metal micronutrients are common in some calcareous soils. Samples of aerial parts of maize and five common weeds and also soil beneath these plants were collected and analyzed to investigate the status and relationships of metal micronutrients in soil, crop, and common weeds of maize field trials at two sites. Results showed that Fe concentration in five studied weeds was higher than that of maize; the highest Fe concentration was found in Convolvolus arvensis and Echinochloa crus-galli (first site) and in Convolvolus arvensis tissues (second site). At both sites, the highest Mn concentration was observed in aboveground parts of Echinochloa crus-galli. The concentration of Mn (both sites) and Fe and Cu (second site) were remarkably higher in Echinochloa crus-galli tissues in comparison with maize. Also the concentrations of Fe (both sites) and Cu (second site) were considerably higher in Convolvolus arvensis tissues in comparison with maize. Available Fe was the highest in the soil beneath Convolvolus arvensis and Portulaca oleracea (first site) and beneath Convolvolus arvensis and Cenopodium album (second site). The high value of available Fe in the soil beneath Convolvolus arvensis may explain why Fe concentration was the highest in aerial parts of this weed species.  相似文献   
99.
Cation exchange capacity (CEC) is an important soil property that is used as an input data in soil and environmental models. Although CEC can be measured directly, its measurement is expensive and time-consuming, therefore pedotransfer functions can be used for estimating it from more readily available soil data. As CEC is highly dependent on soil texture, it may be successfully estimated from the soil textural data. In this study, 20 soils were selected from Fars province, in the south of Iran, and the values of CEC, soil organic matter content, and soil particle size distribution curve of each soil were measured and the geometric mean particle-size diameter (d g ), and the summation of the number of spherical particles for whole parts of the soil particle-size distribution (N) were determined for each soil. Then, five multiple linear regressions were derived between CEC and mentioned soil properties. The results showed that more applicable equation for the study area was based on the percentages of clay, sand and soil organic matter content.  相似文献   
100.
The one dimensional (1D) Ni-ZnO nanoparticles have been synthesized by a simple hydrothermal method. A novel photocatalyst of nanostructured Ni-ZnO which immobilized on polyacrylonitrile nanofibers were successfully fabricated using electrospinnig technique. The structures of nanofibers were characterized by various techniques including Scanning Electron Microscope (SEM), X-ray powder Diffraction (XRD), Fourier transform infrared (FT-IR), UV-Vis diffuse reflectance (DR) and thermogravimetric analys (TGA). The Ni-ZnO/PAN nanofibers photodegradation efficiency was optimized with factorial design method in order to act highly effective in the photocatalytic degradation of Methyle orange (MO). The highest decolorizing efficiencies using introduced material were achieved by 0.8 g l -1 of catalyst and 10 mg l -1 of MO at natural pH under visible light irradiation. The obtained results exhibited that Ni-ZnO/PAN nanofibers have high visible light photocatalitic activities. Overall, the presented material can be used as an efficient, low cost and healthily secure photocatalyst in the field of water treatment.  相似文献   
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