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191.
192.
The interaction of benproperine phosphate (BPP) with eriochrome blue black R (EBBR) in the presence of sodium dodecylbenzene sulphonate (SDBS) was studied using resonance light scattering (RLS) technology and ultraviolet‐visual (UV‐vis) spectrophotometry. Under optimum conditions, BPP reacts with EBBP and SDBS to form a three‐component complex, which results in strong RLS signal and a new RLS peak. The enhanced RLS intensities are proportional to the concentration of BPP over the range 0.6–28.0 µg/mL, with a detection limit of 0.053 µg/mL. The affecting factors as well as the influence of coexisting substances were investigated. The results indicate that this assay method could be applied to the determination of BPP in pharmaceuticals, serum and urine samples with satisfactory results. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
193.
Mingdeng Tang Feng Hu Longhua Wu Yongming Luo Yugen Jiang Changyin Tan 《International journal of phytoremediation》2009,11(1):81-93
A pot experiment and a field experiment were conducted to investigate Cu-enriched composts made from Elsholtzia splendens plants as basal fertilizers to correct Cu deficiency in winter wheat (Triticum aestivum L.) grown in Cu-deficient soils. An application of the compost significantly increased plant height, biomass, grain yield, and 1000-grain weight. In the pot experiment, plant height and shoot biomass in the 2% Cu-rich compost treatment increased 0.8- and 5.2-fold compared with the chemical fertilizer treatment at the mature stage. Compared to chemical fertilizer control, the 2% Cu-enriched compost addition increased grain yield per pot by about 9.5-fold and 1000-grain weight by about 50%. In the field study, the compost also showed stimulatory effects on plant growth and grain yield. The results indicate that composting E. splendens plants grown in a Cu-contaminated soil and then applying the compost to a Cu-deficient soil may be an effective technique for the remediation of contaminated soils and redistribution of the copper as a plant nutrient for copper-deficient soils. 相似文献
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Bolun Cheng Xiao Liang Yan Wen Ping Li Lu Zhang Mei Ma Shiqiang Cheng Yanan Du Li Liu Miao Ding Yan Zhao Feng Zhang 《Journal of cellular biochemistry》2019,120(9):14831-14837
197.
Y Wang R Tang J Tao X Wang B Zheng Y Feng 《The Journal of biological chemistry》2012,287(35):29568-29578
The conversion of renewable cellulosic biomass is of considerable interest for the production of biofuels and materials. The bottleneck in the efficient conversion is the compactness and resistance of crystalline cellulose. Carbohydrate-binding modules (CBMs), which disrupt crystalline cellulose via non-hydrolytic mechanisms, are expected to overcome this bottleneck. However, the lack of convenient methods for quantitative analysis of the disruptive functions of CBMs have hindered systematic studies and molecular modifications. Here we established a practical and systematic platform for quantifying and comparing the non-hydrolytic disruptive activities of CBMs via the synergism of CBMs and a catalytic module within designed chimeric cellulase molecules. Bioinformatics and computational biology were also used to provide a deeper understanding. A convenient vector was constructed to serve as a cellulase matrix into which heterologous CBM sequences can be easily inserted. The resulting chimeric cellulases were suitable for studying disruptive functions, and their activities quantitatively reflected the disruptive functions of CBMs on crystalline cellulose. In addition, this cellulase matrix can be used to construct novel chimeric cellulases with high hydrolytic activities toward crystalline cellulose. 相似文献
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Wei J Ouyang H Wang Y Pang D Cong NX Wang T Leng B Li D Li X Wu R Ding Y Gao F Deng Y Liu B Li Z Lai L Feng H Liu G Deng X 《The FEBS journal》2012,279(1):91-99
Hypertriglyceridemia has recently been considered to be an independent risk factor for coronary heart disease, in which apolipoprotein (Apo)CIII is one of the major contributory factors, as it is strongly correlated with plasma triglyceride levels. Although ApoCIII transgenic mice have been generated as an animal model for the study of hypertriglyceridemia, the features of lipoprotein metabolism in mice differ greatly from those in humans. Because of the great similarity between pigs and humans with respect to lipid metabolism and cardiovascular physiology, we generated transgenic miniature pigs expressing human ApoCIII by the transfection of somatic cells combined with nuclear transfer. The expression of human ApoCIII was detected in the liver and intestine of the transgenic pigs. As compared with nontransgenic controls, transgenic pigs showed significantly increased plasma triglyceride levels (83 ± 36 versus 38 ± 4 mg·dL(-1), P < 0.01) when fed a chow diet. Plasma lipoprotein profiling by FPLC in transgenic animals showed a higher peak in large-particle fractions corresponding to very low-density lipoprotein/chylomicrons when triglyceride content in the fractions was assayed. There was not much difference in cholesterol content in FPLC fractions, although a large low-density lipoprotein peak was identified in both nontransgenic and transgenic animals, resembling that found in humans. Further analysis revealed markedly delayed clearance of plasma triglyceride, accompanied by significantly reduced lipoprotein lipase activity in post-heparin plasma, in transgenic pigs as compared with nontransgenic controls. In summary, we have successfully generated a novel hypertriglyceridemic ApoCIII transgenic miniature pig model that could be of great value for studies on hyperlipidemia in relation to atherosclerotic disorders. 相似文献
200.
Tolerance, the degree to which plant fitness is affected by herbivory, is associated with invasiveness and biological control of introduced plant species. It is important to know the evolutionary changes in tolerance of invasive species after introduction in order to understand the mechanisms of biological invasions and assess the feasibility of biological control. While many studies have explored the evolutionary changes in resistance of invasive species, little has been done to address tolerance. We hypothesized that compared with plants from native populations, plants from invasive populations may increase growth and decrease tolerance to herbivory in response to enemy release in introduced ranges. To test this hypothesis, we compared the differences in growth and tolerance to simulated herbivory between plants from invasive and native populations of Chromolaena odorata, a noxious invader of the tropics and subtropics, at two nutrient levels. Surprisingly, flower number, total biomass (except at high nutrient), and relative increase in height were not significantly different between ranges. Also, plants from invasive populations did not decrease tolerance to herbivory at both nutrient levels. The invader from both ranges compensated fully in reproduction after 50?% of total leaf area had been damaged, and achieved substantial regrowth after complete shoot damage. This strong tolerance to damage was associated with increased resource allocation to reproductive structures and with mobilization of storage reserves in roots. The innately strong tolerance may facilitate invasion success of C. odorata and decrease the efficacy of leaf-feeding biocontrol agents. Our study highlights the need for further research on biogeographical differences in tolerance and their role in the invasiveness of exotic plants and biological control. 相似文献