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991.
T. N. Nazina Qingxian Feng N. K. Kostryukova N. M. Shestakova T. L. Babich Fangtian Ni Jianqiang Wang Liu Min M. V. Ivanov 《Microbiology》2017,86(5):653-665
Microbiological and biogeochemical data on the Kongdian bed (block no. 1) of the Dagang high-temperature oilfield during trials of the biotechnology for enhanced oil recovery are reported. Oil-bearing horizons of block no. 1 are characterized by high temperature (56.9–58.4°C), complex geological conditions, and heavy oil (density 0.966–0.969 g/cm3). The biotechnology implied injecting oxygen as an air-water mixture or H2O2 together with aqueous solution of nitrogen and phosphorus mineral salts through injection wells in order to activate the oilfield microbial community. In the course of trials, an increase in abundance of aerobic and anaerobic microorganisms was revealed, as well as increased methanogenesis rate in formation water. Microbial oxidation of heavy oil resulted in increased concentration of mineral carbonates dissolved in formation water, changes in the stable carbon isotopic composition δ13C/Σ(CO2 + HCO3 - + CO3 2-), formation of biosurfactants, and decreased interfacial tension of formation water. Application of the biotechnology at the Kongdian bed (block no. 1) resulted in additional recovery of 6331 t oil. Oil viscosity in the zone of production wells located at the North block of the Kongdian bed decreased by 11%. A total of 46152 t additional oil was recovered at three experimental sites of the Dagang oilfield (North block and block no. 1 of the Kongdian bed and the Gangxi bed), which is an indication of high efficiency of the technology for activation of the oilfield microflora for heavy oil replacement from high-temperature oilfields. 相似文献
992.
Osteoclast differentiation gene expression profiling reveals chemokine CCL4 mediates RANKL‐induced osteoclast migration and invasion via PI3K pathway 下载免费PDF全文
Wenhua Xuan Xiaoke Feng Chen Qian Liuying Peng Yumeng Shi Lingxiao Xu Fang Wang Wenfeng Tan 《Cell biochemistry and function》2017,35(3):171-177
The migration of osteoclasts (OCs) from circulation and bone marrow into bone surface plays a critical role in the pathogenesis of some bone resorptive diseases, such as rheumatoid arthritis and osteoporosis. To date, how the migration of OCs remains unclear. We investigated gene expression profiling in osteoclastic differentiation of bone marrow–derived macrophages (BMMs) into OCs by microarray analysis. We identified 387 genes overexpressed in osteoclastic differentiation of BMMs. Among them, chemokine CCL4 showed a robust up‐regulation signal. High expression of CCL4 was validated in primary BMMs and OC precursor cell line RAW264.7 during differentiation into OCs. The CCL4 neutralization decreased RANKL‐induced OC precursor cell migration and invasion in Matrigel‐coated transwell membranes assay and in vitro wound healing assay. However, CCL4 inhibition did not affect OCs differentiation and differentiation associated gene expression. The CCL4 inhibition promoted the PI3K phosphorylation at 45 to 60 minutes after RANKL stimulation in RAW264.7. This study indicated that chemokine CCL4 is an important regulator for OCs migration via PI3K pathway, providing a novel therapy target for bone resorptive diseases. 相似文献
993.
994.
Molecular phylogeography of four endemic Sagittaria species (Alismataceae) in the Sino‐Japanese Floristic Region of East Asia 下载免费PDF全文
Yi‐Ying Liao Andrew Wanyoike Gichira Qing‐Feng Wang Jin‐Ming Chen 《Botanical journal of the Linnean Society. Linnean Society of London》2016,180(1):6-20
To reveal the role of climate oscillations of the Quaternary in forming the contemporary plant diversity in the temperate Sino‐Japanese Floristic Region of mainland China, we assess the phylogeographical patterns of four Sagittaria species in the region using sequence data from plastid DNA non‐coding regions (psbA‐trnH, the rpl16 intron and trnC‐ycf6) and the internal transcribed spacers of nuclear ribosomal DNA (nrITS). Based on both datasets, the divergence time among the four studied species was estimated to fall in the Late Tertiary (plastid DNA: 7.1–13.7 Mya; ITS: 11.1–16.1 Mya). The ancestral distribution analyses revealed that regions with a great diversity in topography, climate and ecological conditions, e.g. the Hengduan Mountains, Central China and East China, were the areas where the endemics originated. Mismatch distribution analyses revealed that each species had experienced a range expansion in response to Quaternary climatic oscillations. Our findings contradict the hypothesis of Quaternary origins of the endemic Sagittaria spp.; we support the view that modern species in the Northern Hemisphere originated mostly during the Tertiary. Range expansion may have profoundly modified the current distribution ranges of Sagittaria species in the Sino‐Japanese Floristic Region. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2016, 180 , 6–20. 相似文献
995.
Possible target‐related proteins and signal network of bufalin in A549 cells suggested by both iTRAQ‐based and label‐free proteomic analysis 下载免费PDF全文
Dong‐Mei Zhang Li‐Xing Feng Miao Liu Wen‐Hai Jin Ji Luo Ai‐Ying Nie Yue Zhou Yin Li Wan‐Ying Wu Bao‐Hong Jiang Min Yang Xuan Liu 《Proteomics》2016,16(6):935-945
Bufalin (BF) exhibited antiproliferation and antimigration effects on human A549 lung cancer cells. To search its target‐related proteins, protein expression profiles of BF‐treated and control cells were compared using two quantitative proteomic methods, iTRAQ‐based and label‐free proteomic analysis. A total of 5428 proteins were identified in iTRAQ‐based analysis while 6632 proteins were identified in label‐free analysis. The number of common identified proteins of both methods was 4799 proteins. By application of 1.20‐fold for upregulated and 0.83‐fold for downregulated cutoff values, 273 and 802 differentially expressed proteins were found in iTRAQ‐based and label‐free analysis, respectively. The number of common differentially expressed proteins of both methods was 45 proteins. Results of bioinformational analysis using MetacoreTM showed that the two proteomic methods were complementary and both suggested the involvement of oxidative stress and regulation of gene expression in the effects of BF, and fibronectin‐related pathway was suggested to be an important pathway affected by BF. Western blotting assay results confirmed BF‐induced change in levels of fibronectin and other related proteins. Overexpression of fibronectin by plasmid transfection ameliorated antimigration effects of BF. Results of the present study provided information about possible target‐related proteins and signal network of BF. 相似文献
996.
Jun Feng Su Sheng Chen Zheng Ting Lin Huang Fang Ma Si Cheng Shao Shao Fei Yang 《Geomicrobiology journal》2016,33(7):586-591
A novel bacterium, strain SZ28, identified as Acinetobacter sp., showed anaerobic denitrification ability using Mn(II) as the electron donor. Nitrate-nitrogen concentration decreased from nearly 16.52–mg L?1 to 4.4–mg L?1, without accumulation of nitrite as an intermediate, with a maximum of 0.063–mg NO3?-N L?1 h?1, reaching a peak of 0.085–mg NO3?-N L?1 h?1 in sodium acetate. The nitrate removal rate reached 0.067–mg NO3?-N L?1 h?1, 0.059–mg NO3?-N L?1 h?1, and 0.078 mg NO3?-N L?1 h?1 using Mn(II), S(II), and Fe(II) as electron donors, respectively. The optimum pH was 6.0, with a removal rate of 0.063–mg NO3?-N L?1 h?1 相似文献
997.
间歇曝气对微污染源水生物接触氧化修复系统脱氮性能的影响 总被引:1,自引:0,他引:1
针对寡营养生境下生物脱氮过程碳源不足等问题,开展不同间歇曝气方式对微污染源水生物接触氧化修复系统脱氮性能的影响研究,探究修复系统短程硝化反硝化的可行性与过程机理.结果表明:在停曝-曝气时间为8 h-16 h的间歇曝气方式(Ⅰ)下启动的生物接触氧化修复系统,其铵态氮(NH+4-N)、高锰酸盐指数(CODMn)、总氮(TN)的平均去除率分别稳定在93.0%、78.1%、19.4%;而在停曝-曝气时间为16 h-8 h的间歇曝气方式(Ⅱ)下运行修复系统,其NH+4-N、CODMn平均去除率仍能分别维持在81.2%、76.4%,体系内NO-2-N发生积累,TN去除率增至50%以上.对工况Ⅱ下修复系统周期内氮素转化特性分析发现,在确保出水NH+4-N、溶解氧(DO)浓度达标的前提下,缩短曝气时间可将体系DO长时间控制在0.5~1.5 mg·L-1,亚硝酸氧化菌(NOB)生长及其活性受到抑制,NO-2-N明显累积,最终实现了微污染源水生物接触氧化修复系统的短程生物脱氮. 相似文献
998.
从大叶醉鱼草的叶子中分离得到一株内生真菌LL3026,以卤虫模型测稀释后发酵液的杀虫活性,结果表明LL3026发酵液杀虫活性较强,且温度、光照及紫外照射对LL3026发酵液杀虫活性影响不显著;采用分子生物学方法对LL3026菌株rDNA的ITS基因(ITS-5.8S rDNA)进行PCR扩增、测序,构建系统发育树。ITS基因显示其属于刺盘孢属真菌。 相似文献
999.
植物生长调节剂浸球对花芽分化期石蒜和换锦花鳞茎生化特性的影响 总被引:1,自引:0,他引:1
在栽植前采用0(CK)、60、120和180 mg·L-16-BA、GA3和乙烯利对石蒜〔Lycoris radiata(L’Hér.)Herb.〕和换锦花(L.sprengeri Comes ex Baker)鳞茎进行浸球处理,对花芽分化期内(4月至7月)石蒜和换锦花鳞茎中可溶性糖、可溶性蛋白质和核酸含量的变化进行了比较分析。结果表明:在花芽分化期内,随时间的推移,对照组石蒜和换锦花鳞茎中可溶性糖、可溶性蛋白质和核酸含量呈先增加后降低的趋势,并在6月25日(心皮分化期)或7月10日(雌蕊分化期)达到最高值。经60、120和180 mg·L-16-BA、GA3和乙烯利浸球处理后,石蒜和换锦花鳞茎中可溶性糖、可溶性蛋白质和核酸含量在花芽分化期内先逐渐增加,至6月25日或达到峰值后开始下降或继续升高;但与对照相比,随时间的推移,石蒜鳞茎中可溶性糖含量总体上有不同程度的增加,而换锦花鳞茎中可溶性糖含量或高或低无规律性的变化,但各处理组石蒜和换锦花鳞茎中可溶性糖含量均与对照间有差异;可溶性蛋白质含量在进入花原基形成期(5月10日)后始终维持在较高的水平;核酸含量在花芽分化期的前期维持在较低的水平,在雌蕊分化期迅速增加... 相似文献
1000.
植物-害虫-天敌互作机制研究前沿 总被引:15,自引:8,他引:15
植物-害虫-天敌之间的三级营养互作关系是当今进化生态学和化学生态学研究领域的前沿课题,也是寻找害虫可持续控制途径的重要基础。自2006年以来,我国昆虫学家在973项目《重大农业害虫猖獗危害的机制及可持续控制》的支持下,围绕害虫、植物、天敌协同进化机理的关键科学问题,以棉花-害虫-天敌、水稻-害虫-天敌和蔬菜-害虫-天敌系统为研究对象开展研究,发现OsHI-LOX参与虫害诱导的水稻茉莉酸(JA)信号途径合成,并通过水稻对二化螟和褐飞虱不同抗性作用的调控;寄主植物烟草受到棉铃虫和烟青虫危害后将被诱导产生化学防御作用,但它们的作用不同;绿叶挥发物(3Z)-hexen-ol是寄生蜂天敌定位寄主的最关键化合物,植物-害虫-天敌之间的互作关系受到光周期和CO2浓度升高而改变;植物对害虫直接的防御和通过寄生蜂对害虫的间接防御存在"权衡"关系;转基因棉花种植加重了盲椿象灾变。这些研究成果在Science,New Phytology,Plant Journal,Plant,Cell and Environment等刊物上发表论文150余篇,极大地提高了我国在作物-害虫-天敌三者之间关系的研究水平。 相似文献