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61.
62.
Jun Feng Su Chun Yu Gao Ting Lin Huang Xue Chen Bai Hai Rong Zhu 《Geomicrobiology journal》2019,36(5):396-404
In this study, the denitrification performance of the mixotrophic biological reactor was investigated under varying Fe(II)/Mn(II) molar ratio conditions. Results indicate that the optimal nitrate removal ratio occurred at an Fe(II)/Mn(II) molar ratio of 9:1, pH of 7, with an HRT of 10?h. When the reactor was performing under optimal conditions, the nitrate removal reached 100.00% at a rate of 0.116?mmol·L?1·h?1. The proportion of oxidized Fe(II) and Mn(II) reached 99.29% and 21.88%, respectively. High-throughput sequencing results show that Pseudomonas was the dominant species in the mixotrophic biological reactor. Furthermore, the relative abundance of Pseudomonas and denitrification performance was significantly influenced by variation in the Fe(II)/Mn(II) molar ratio. 相似文献
63.
Xiaobin Zeng Chen-Yang Li Hai Wang Qian Qiu Guofu Qiu Xiangjiu He 《Phytochemistry letters》2013,6(1):36-40
A 70% ethanol extract from the roots of Livistona chinensis has been investigated, led to the isolation of 18 compounds, including two new 6′-O-acyl-β-d-glucosyl-β-sitosterols, 6′-O-(2″-hydroxyheptadecanoyl)-β-d-glucosyl-β-sitosterol (1) and 6′-O-(icosa-9″Z,12″Z-dienoyl)-β-d-glucosyl-β-sitosterol (2), two new keto esters, ethyl 16-(dodeca-4″′Z,7″′Z-dienyl)-29-oxo-15-(tetradeca-5″Z,8″Z,11″Z-trienyl) triacontanoate (7), and 16-hydroxy-8-oxohexadecyl tetradecanoate (9), a new unsaturated fatty acid, tetracosa-(11Z,14Z,18Z)-trienoic acid (8), as well as a new fatty alcohol, 10-decylnonadecane-1,19-diol (10). The structures of new compounds were elucidated, based on spectroscopic and chemical methods. The antiproliferative activity against four human tumor cell lines (K562, HL-60, HepG2, and CNE-1) was evaluated. Four compounds (1–3, 5) showed potent antiproliferative effects with the IC50 of 10–100 μM. To our knowledge, this is the first report of the occurrence of 6′-O-acyl-β-d-glucosyl-β-sitosterol and 3-O-acyl-β-sitosterol in the genus Livistona. Keto fatty acids and their esters are also rare in higher plant. 相似文献
64.
巨噬细胞产生NO.和O_2~-自由基的分子机理 总被引:2,自引:0,他引:2
建立了用顺磁共振(ESR)和化学发光技术测定巨噬细胞产生NO和氧自由基的方法.捕捉到了巨噬细胞受佛波酯刺激产生的NO.和O-2自由基.测定了在不同浓度L-精氨酸存在时佛波酯刺激后巨噬细胞产生的NO自由基.研究了巨噬细胞产生的NO和氧自由基的分子机理.结果表明巨噬细胞不仅产生氧自由基而且产生NO自由基.NADPH氧化酶产生氧自由基的部位位于巨噬细胞膜的外侧.NO合成酶活化产生NO自由基比NADPH氧化酶活化产生氧自由基晚几分钟. 相似文献
65.
鹤山南亚热带草坡生态系统的热量平衡 总被引:5,自引:0,他引:5
本文以广东鹤山丘陵综合试验站草坡为研究对象,分析了鹤山南亚热带草坡的能量平衡特征,主要结果如下:1.辐射平衡的各分量中,蒸发散耗热占净辐射的74.7%,其年变化幅度较大;湍流热通量占净辐射的21.2%,其月变化没有明显的规律,波动较大,土壤热通量与其它分量相比,其比重要小得多。2.虽然鹤山年幅射量和降雨量较多,但水热条件有几个月配合欠佳,使得草坡的净辐射能有90%以上用于地面以上植被和空气湍流交换所消耗,小气候条件较差,影响了这一生态系统的生产潜力的发挥。3.太阳辐射透过大气层以后,仅有4775.2MJm-2a-1左右的辐射能到达草坡,草坡反射了822.5MJm-2a-1,其净幅射收人为2915.6MJm-2a-1,净辐射收人中又有2077.8MJm-2a-1用于蒸散作用,618.1MJm-2a-1用于湍流热交换,87.5MJm-2a-1用于土壤热交换,植被贮热约38.8MJm-2a-1;用于净光合作用耗热93.4MJm-2a-1。 相似文献
66.
67.
Hai B. Tran Suzanne Maiolo Rebecca Harper Peter D. Zalewski Paul N. Reynolds Sandra Hodge 《Cell biology international》2021,45(11):2368-2379
Recently identified molecular targets in pulmonary artery hypertension (PAH) include sphingosine-1-phosphate (S1P) and zinc transporter ZIP12 signaling. This study sought to determine linkages between these pathways, and with BMPR2 signaling. Lung tissues from a rat model of monocrotaline-induced PAH and therapeutic treatment with bone marrow–derived endothelial-like progenitor cells transduced to overexpress BMPR2 were studied. Multifluorescence quantitative confocal microscopy (MQCM) was applied for analysis of protein expression and localization of markers of vascular remodeling (αSMA and BMPR2), parameters of zinc homeostasis (zinc transporter SLC39A/ZIP family members 1, 10, 12 and 14; and metallothionein MT3) and S1P extracellular signaling (SPHK1, SPNS2, S1P receptor isoforms 1, 2, 3, 5) in 20–200 µm pulmonary microvessels. ZIP12 expression in whole lung tissue lysates was assessed by western blot. Spearman nonparametric correlations between MQCM readouts and hemodynamic parameters, Fulton index (FI), and right ventricular systolic pressure (RVSP) were measured. In line with PAH status, pulmonary microvessels in monocrotaline-treated animals demonstrated significant (p < .05, n = 6 per group) upregulation of αSMA (twofold) and downregulation of BMPR2 (20%). Upregulated ZIP12 (92%), MT3 (57.7%), S1PR2 (54.8%), and S1PR3 (30.3%) were also observed. Significant positive and negative correlations were demonstrated between parameters of zinc homeostasis (ZIP12, MT3), S1P signaling (S1PRs, SPNS2), and vascular remodeling (αSMA, FI, RVSP). MQCM and western blot analysis showed that monocrotaline-induced ZIP12 upregulation could be partially negated by BMPR2-targeted therapy. Our results indicate that altered zinc transport/storage and S1P signaling in the monocrotaline-induced PAH rat model are linked to each other, and could be alleviated by BMPR2-targeted therapy. 相似文献
68.
EBV is detected in more and more tumors, and is relative to carcinogenesis. We studied the copies of EBV DNA in whole blood of NPC patients and healthy controls by real-time quantitative PCR. In the 73 NPC patients and 83 controls, the positive rate of EBV in blood of NPC is 46.6%, while 13.3% in control. The mean copy number is 3.9 x 10(4) copys/microgram DNA in controls, which is much higher than NPC patients (which is 1.7 x 10(5) copies/microgram DNA). EBV infection is relative with NPC, while the lytic form of EBV maybe more important than its latent form. These results suggest that whole blood EBV DNA may be a valuable tool for molecular diagnosis of NPC. 相似文献
69.
MicroRNA‐339‐3p alleviates inflammation and edema and suppresses pulmonary microvascular endothelial cell apoptosis in mice with severe acute pancreatitis‐associated acute lung injury by regulating Anxa3 via the Akt/mTOR signaling pathway 下载免费PDF全文
Xing‐Mao Wu Kai‐Qiang Ji Hai‐Yuan Wang Yang Zhao Jia Jia Xiao‐Peng Gao Bin Zang 《Journal of cellular biochemistry》2018,119(8):6704-6714
70.
目的:建立一种适用于人工miRNA(amiRNA)表达研究的克隆载体。方法:基于实验室构建的短发夹RNA(shRNA)表达载体pshOK-basic,将鼠源miRNA-155的侧翼序列插入合适的酶切位点构建得到amiRNA重组表达载体pOK-basic;应用本载体分别构建靶向萤火虫荧光素酶(luc2)和红色荧光蛋白(mCherry)基因的amiRNA并检测其沉默效果。结果:应用此载体能快速高效地构建amiRNA,靶向luc2和mCherry报告基因的amiRNA能较好地抑制靶基因的表达。结论:构建了一种能高效表达amiRNA的克隆载体,为amiRNA的进一步研究及应用奠定了基础。 相似文献