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111.
银杏叶提取物(EGb761)对红细胞脂质过氧化损伤的影响 总被引:6,自引:0,他引:6
观察银杏叶提取物(EGb761)对红细胞脂质过氧化损伤的影响,探讨其保护红细胞的机制。以活性氧(H2 O2 )作用于离体的正常红细胞,观察EGb761对红细胞溶血度、红细胞丙二醛含量(MDA)、红细胞超氧化物歧化酶(SOD)和ATP酶(ATPase)活性及红细胞膜骨架结构的影响。结果表明:EGb761能明显降低红细胞溶血度,且随着浓度增加其作用逐渐增强,与对照组比较差异有极显著性(t =4.13~19.41,P <0 .0 5 ,0 .0 0 1) ;EGb761能明显降低红细胞MDA含量,提高其SOD ,ATPase酶活性,与对照组比较差异有极显著性(t =2 .0 2~70 .0 6,P <0 .0 5 ,0 .0 0 1) ;EGb761能降低过氧化损伤对红细胞膜骨架的破坏,保护其完整性。可见EGb761能在膜水平上直接对抗氧自由基引发的红细胞脂质过氧化损伤,保护红细胞及其膜骨架结构。 相似文献
112.
Aspects of the usefulness of five marine pollution biomarkers, with emphasis on MN and lipid content
By using cellular biomarkers, such as the formation of the micronucleus, the morphometric alterations of lipids and the morphometric changes in the lysosomal system, we investigated effects of experimental exposure to phenanthrene, Cu, Cd, and Hg for 15 days in mussels. Concerning micronuclei, the evaluation of the total nuclear abnormalities, instead of the micronucleus only, as a biomarker of marine pollution, indicated more statistically significant differences between the control and the pollutant treated groups. Contrary to the existing knowledge showing that there is an increase in lipid content after pollutant exposure, our results showed that there was a decrease in the amount of lipid, as well as an increase in the number of neutral lipids. Furthermore, although prior studies found that fewer lysosomes formed after pollutant exposure, this was not confirmed by our work, as pollutant treated animals exhibited a decrease in the volume and an increase in the numerical density of lysosomes, compared to control groups. 相似文献
113.
投加粉末活性炭对MBR运行性能的影响 总被引:4,自引:0,他引:4
试验研究比较了在相同的进水和运行条件下,反应器1(投加粉末活性炭,投加量为12.3 g,使其质量浓度达到1 100 mg/L)和反应器2(未投加粉末活性炭)的膜透水性及对污染物的去除效果,并分析了粉末活性炭可以提高膜过滤性能的相关机理。试验结果表明:反应器1的膜通量衰减速率明显小于反应器2;投加粉末活性炭改变了混合液的性质,也大大降低了混合液中胞外聚合物和微细胶体的含量,从而减缓了膜通量的下降速度,可以使系统长时间地以相对高的膜通量运行。 相似文献
114.
壳聚糖超滤复合膜研制 总被引:1,自引:0,他引:1
以聚醚砜(PES)、聚偏氟乙烯(PVDF)超滤膜、聚己内酰胺(尼龙-6)微孔滤膜为多孔支撑膜,将天然聚合物壳聚糖通过流涎法制成超滤复合膜。该复合膜性能优良,在操作压力为0.25MPa的条件下,它对聚乙二醇(PEG)的截留率及其渗透速度,分别为87.2%~98.4%和2.1~59.0L/(m2h)。壳聚糖超滤复合膜性能的优劣与支撑膜的材质、孔径、壳聚糖的浓度、添加剂的分子量及成膜时的条件有关。 相似文献
115.
Antitumor activity is one characteristic function of some certain antimicrobial peptides(AMPs) found in recent years. In the present study, we attempted to detect potential anticancer activity of a recombinant piscidin 5-like from Larimichthys crocea(r Lc-P5L) which owned widely antibacterial and strong antiparasitic activity in vitro.The light microscope observation indicated r Lc-P5L was of antitumor activity to He La cells, 293 T cells and L929 cells. MTT assay showed the toxic sensitivity of... 相似文献
116.
Linear theories to analyse a floating and liquid-filled membrane structure in head- and beam-sea waves have been presented. The dynamic solutions are based on a small perturbation of the static solution, and the hydroelastic deformation has been taken care of correctly to the first order of the incident wave amplitude. A new experiment has been carried out for measuring the dynamic tensions of a membrane. A comparison between the theories and experiment are presented for the dynamic hoop tension. 相似文献
117.
Sathish Raam Ravichandran Chitra Devi Venkatachalam Mothil Sengottian Sarath Sekar Bhavya Shri Subramaniam Ramasamy Sakthivel Elangovan Siddharth Thorali Sivakumar Shanmuga Sundaram Subramanian 《洁净——土壤、空气、水》2023,51(3):2100305
In the present study, nanocomposite polymeric membranes are fabricated using polyvinyl alcohol (PVA), cellulose acetate (CA) as polymers, and dimethyl sulfoxide (DMSO) as the solvent. To enhance the performance of the membrane, nanoparticles like TiO2, CaO, CdO, and ZrO are added to the polymeric solution and the doped polymeric solution is cast on a glass plate. Nine combinations of membranes are fabricated with two different concentrations (0.1% and 0.2%) of nanoparticles. The basic properties of the membranes such as density, porosity, viscosity, permeability, pure water flux, and water content are studied for the samples. Membrane pore structure and surface properties are identified and it is found that doping nanoparticles on the surface of membranes improve mechanical strength, stability, pore size, etc., allowing the membranes to perform better in extreme industrial-level effluent treatment applications. High-resolution scanning electron microscopy (SEM) shows the homogeneous dispersion of ZrO, TiO2, CaO, and CdO nanoparticles on the surface of the PVA-CA membrane. The doping of nanoparticles on the PVA-CA membrane results in improved mechanical strength and good chemical oxidation stability. In comparison, the PCD-TiO2 sample shows high thermal stability and oxidation stability at high temperatures until 200°C, which has a high potential for treating industrial effluents. 相似文献
118.
Nguyen Duc Toan Nguyen Van Tuyen Pham Bang Hai Nguyen Thi Hoang Ha Do Tien Anh Bach Quang Dung 《洁净——土壤、空气、水》2023,51(1):2200106
A single bioaugmentation reactor and a side-stream gaslift membrane bioreactor combined with bioaugmentation are conducted to treat real wastewater from a centralized piggery slaughterhouse in Vietnam. The bioaugmented reactor is inoculated with heterotrophic microorganisms (Bacillus sp.) isolated from piggery slaughterhouse wastewater. The results of a single bioaugmentation experiment show high removal efficiency of chemical oxygen demand (COD) (84.8%–97.5%) and total nitrogen (TN) (69.9%–87.2%) at loading rates of 1.28–3.89 and 0.14–0.37 kg m−3 d−1, respectively. The combined system demonstrates a significantly higher TN removal efficiency (89.0%–96.1%) (p < 0.001), more stable flux (36.0–38.4 L m−2 h−1), and transmembrane pressure (0.95–1.05 bar), and better capacity of separation of solid–liquid phases compared to the single bioaugmentation. High COD and TN removal efficiency is possibly due to assimilation and simultaneous nitrification and denitrification processes. The results of this study also indicate the feasibility and propitious efficiency of the bioaugmented gaslift membrane bioreactor for piggery slaughterhouse wastewater treatment. 相似文献
119.
120.
硼化物因具有质轻、阻燃、耐热、高硬、耐磨等优良性能而应用广泛,目前国内硼资源开发力度不足导致硼进口量高达70%。随国内盐湖与海水资源开发产业兴起,利用提硼彻底、工艺简洁、材料可循环利用的吸附法从水溶液中分离提取硼资源成为研究热点。综述了国内外多种无机硼吸附材料、有机硼吸附材料、有机-无机杂化硼吸附材料的研究现状,重点对比了有机硼吸附材料中的螯合树脂型和螯合膜型材料,并对硼吸附材料的发展趋势进行了展望,为盐湖卤水提硼及海水淡化提硼产业技术开发中硼吸附材料的选择提供参考。 相似文献