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La3+,Ce3+对厌氧颗粒污泥在不同VFA底物中的产甲烷促进效应 总被引:4,自引:0,他引:4
采用静态实验研究了分别添加O.05mg·L^-1La^3+和Ce^3+对不同来源和保存状况条件下不同VFA底物的厌氧颗粒污泥产甲烷的影响。结果表明,乙酸为底物时加入Ce^3+,丙酸加入La^3+或Ce^3+,乳酸加入La^3+时都大大加快了反应初期污泥的产甲烷速率,且对比产甲烷活性SMA也有3%-8%的提高;O.05mg·L^-1La^3+或Ce^3+的加入使污泥利用丙酸的速度加快,对于厌氧反应器的恢复运行有一定的实际意义。甲酸为底物时,La^3+,Ce^3+的加入对污泥产甲烷曲线形状没有影响,对SMA则分别降低了9.21%和3.37%;乙酸添加La^3+在反应初期明显降低了产甲烷速率,但SMA并未降低。厌氧颗粒污泥经长时间低温存放后,原来对其SMA有提高作用的稀土浓度此时可能会作用不明显甚至会降低SMA;低浓度稀土离子对污泥产甲烷活性产生抑制作用时,相同质量浓度下Ce^3+比La^3+对污泥的抑制作用小;驯化培养过程有利于污泥对稀土的适应。 相似文献
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HUANG Zeng-yan HUANG Man-ping PENG Chun-li LIU Yong-yuan LI Chun-yan LIANG Dong-hui 《园艺学报》2021,37(1):34-40
AIM To observe effects of emotional stimulation on expression of stromal cell-derived factor-1(SDF-1) and CXC chemokine receptor 4 (CXCR4) in plasma, platelets, aortas, hippocampus and bone marrow of apolipoprotein E gene knockout (ApoE -/-) mice, and to reveal the possible mechanism of the aggravated atherosclerotic plaque vulnerability by emotional stimulation. METHODS Thirty 8-week-old male ApoE -/- mice were randomly divided into normal control group, high fat group, and emotional stimulation group. Ten 8-week-old inbred C57BL/6J mice served as blank control group. After 12 weeks of intervention, the serum levels of SDF-1 and CXCR4 were investigated by ELISA. The protein levels of SDF-1 and CXCR4 in platelets, aortas, hippocampus and bone marrow were determined by Western blot. The pathological damage of aortas was observed by oil red O staining. RESULTS Compared with blank control group, normal control group and high fat group, the mice subjected to emotional stimulation showed more serious atherosclerosis in aortas detected by oil red O staining, and increased levels of SDF-1 and CXCR4 in the plasma and aortas were also observed (P <0.05). The results of Western blot showed that the protein levels of SDF-1 and CXCR4 in platelets, aortas and hippocampus were increased in the mice subjected emotional stimulation, but the expression of SDF-1 and CXCR4 in the bone marrow was decreased (P <0.05). CONCLUSION Imbalance of SDF-1/CXCR4 may be the key target by which emotional stimulation accelerates the progression of atherosclerosis. 相似文献
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I. Placha M. Pogany Simonova K. Cobanova A. Laukova S. Faix 《Research in veterinary science》2010,89(2):257-261
We investigated the effect of Enterococcus faecium on phagocytic activity, antioxidative status in vivo and the effect of E. faecium and 0.4% concentration of Thymus vulgaris essential oil (EO) on the duodenal tissue integrity in vitro in laying hens. The birds were fed the same standard diets and were divided into four groups. E. faecium was added to the drinking water for the second and fourth groups. EO was added to special chambers for measuring trans-epithelial electrical resistance (TEER) for the third and fourth groups only. TEER was lower in groups where EO was added, but in the group with E. faecium TEER was not changed significantly. Our results show that EO at 0.4% concentration may negatively affect intestine integrity, and the probiotic strain E. faecium AL41 is able to eliminate this effect and can strengthen non-specific immunity. To confirm our findings further histopathological investigations of intestinal tissue are needed. 相似文献
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中草药制剂对泌乳奶牛机体免疫性能的影响 总被引:1,自引:0,他引:1
试验采用大青叶、大黄、党参等19味中草药分别组成内服和子宫灌注制剂治疗奶牛子宫内膜炎,并采集颈静脉血测定淋巴细胞刺激指数(SI)和中性粒细胞吞噬力,以观察中草药制剂对奶牛免疫性能的影响。结果显示,中草药制剂均可提高奶牛免疫力,内服中草药制剂应用效果优于子宫灌注制剂(P〈0.05);复方制剂优于单味中草药制剂(P〈0.05);复方中草药内服制剂可使淋巴细胞刺激指数(SI)和中性粒细胞吞噬力分别提高53.76%和4.58%(P〈0.01);复方子宫灌注制剂可使淋巴细胞刺激指数(SI)和中性粒细胞吞噬力分别提高39.58%和1.98%(P〈0.01)。 相似文献
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刘奎玉 《新农村(黑龙江)》2010,(4):82-83
针对机电安装问题展开讨论,归纳了机电设备安装常见技术及相关管理问题;对技术改善提出相关意见陈述;强调了通电调试的重要性以引起重视;最后验收。 相似文献
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Inhibitory and promotive allelopathy in rice (Oryza sativa L.) 总被引:2,自引:1,他引:2
Studies on allelopathic rice, which inhibits the germination and development of weeds such as barnyardgrass ( Echinochloa spp.) and ducksalad [ Heteranthera limosa (Sw.) Wild.], have been strongly conducted in the USA, the Philippines, Japan, Korea, and other countries since the 1980s. Weed-suppressing rice plants can compete with weeds for light and mineral nutrients by their rapid and thick growth characteristics, and probably also by their allelopathic effects. It was suggested that allelopathic properties were inherited from parents. Different screening methods for finding allelopathic rice simply and rapidly have been proposed. In contrast, stimulative allelopathy in rice, which promotes germination of the dormant and dormancy-awakened seeds of Monochoria vaginalis (Burm. f.) Kunth var. vaginalis , has been investigated by the authors since the 1990s. Rice seeds promoted the germination in the dark and in light under submerged conditions. Our experiments suggested that rice seeds, hulls, plants and straw contain stimulative substance(s) that promote seed germination of M. vaginalis . 相似文献