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The stress response factor RpoS is required for the natural transformation of Escherichia coli

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Chinese Science Bulletin 2014年第5期59卷 521-527页

作者： yan Zhang Mengyue Guo ping Shen Zhixiong xie Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education) State Key Laboratory of Virology College of Life Sciences Wuhan University

The natural transformation of Escherichia coli is a novel and recently developed system that has significance for genetic studies and the biological safety of genetic ***,the mechanisms of transformation,including development of competence and DNA uptake,are not thoroughly *** this study,we demonstrated the effect of the general stress response regulator RpoS,which has been associated with *** transformation,on natural transformation performed in an‘‘open system’’.We find that RpoS is required for natural transformation but not to artificial transformation and RpoS mainly affect transformation in the liquid culture prior to *** the liquid culture,RpoS over-expression promotes natural transformation in early exponential phase and static incubation accumulates RpoS and promotes transformation to a limited *** findings provide detailed understanding of RpoS function on natural transformation.

关键词：大肠杆菌转化响应系数天然改造自然应力大肠埃希氏菌开放系统

老年急性冠脉综合征经皮冠状动脉介入治疗术后并发慢血流事件的危险因素分析

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实用老年医学 2018年第3期32卷 249-251页

作者：陈雪梅何艳萍余勰张贵方重庆市中医院急诊ICU 四川省重庆市400021

目的探讨老年急性冠脉综合征(ACS)病人经皮冠状动脉介入治疗(PCI)术后慢血流事件的危险因素。方法回顾性分析行PCI治疗的ACS病人95例,包括不稳定型心绞痛(UAP)59例和急性心肌梗死(AMI)36例,依据其是否发生慢血流事件分为慢血流组(n=32)... 详细信息

目的探讨老年急性冠脉综合征(ACS)病人经皮冠状动脉介入治疗(PCI)术后慢血流事件的危险因素。方法回顾性分析行PCI治疗的ACS病人95例,包括不稳定型心绞痛(UAP)59例和急性心肌梗死(AMI)36例,依据其是否发生慢血流事件分为慢血流组(n=32)和血流正常组(n=63)。比较2组的一般临床资料及尿素氮(BUN)、肌酐(SCr)和D-二聚体(D-dimer)等指标水平,采用多因素Logistic回归分析慢血流发生的危险因素。结果 2组的年龄、糖尿病史、高血脂、吸烟史及D-dimer水平比较,差异均有统计学意义(P<0.05);Logistic回归分析表明,年龄(OR=3.618,95%CI:1.337~7.522)、糖尿病史(OR=4.781,95%CI:1.405~7.724)、高血脂(OR=5.026,95%CI:1.520~9.875)、吸烟史(OR=5.155,95%CI:1.596~10.337)和D-dimer(OR=5.547,95%CI:1.662~11.347)与PCI术后慢血流事件的发生独立相关。结论年龄、糖尿病史、高血脂、吸烟史和D-dimer是PCI术后慢血流事件发生的危险因素。

关键词：急性冠脉综合征 D-二聚体慢血流经皮冠状动脉介入治疗

Biological mechanisms driving the seasonal changes in the internal loading of phosphorus in shallow lakes

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Science China Earth Sciences 2006年第z1期49卷 14-27页

作者： xie ping Donghu Experimental Station of Lake Ecosystems State Key Laboratory of Freshwater Ecology and Biotechnology of ChinaInstitute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China

Because of the obvious importance of P as a nutrient that often accelerates growth of phytoplankton (including toxic cyanobacteria) and therefore worsens water quality, much interest has been devoted to P exchange across the sediment-water interface. Generally, the release mode of P from the sediment differed greatly between shallow and deep lakes, and much of the effort has been focused on iron and oxygen, and also on the relevant environmental factors, for example, turbulence and decomposition, but a large part of the P variation in shallow lakes remains unexplained. This paper reviews experimental and field studies on the mechanisms of P release from the sediment in the shallow temperate (in Europe) and subtropical (in the middle and lower reaches of the yangtze River in China) lakes, and it is suggested that pH rather than DO might be more important in driving the seasonal dynamics of internal P loading in these shallow lakes, i.e., intense photosynthesis of phytoplankton increases pH of the lake water and thus may increase pH of the surface sediment,leading to enhanced release of P (especially iron-bound P) from the sediment. Based on the selective pump of P (but not N) from the sediment by algal blooms, it is concluded that photosynthesis which is closely related to eutrophication level is the driving force for the seasonal variation of internal P loading in shallow lakes. This is a new finding. Additionally, the selective pump of P from the sediment by algal blooms not only explains satisfactorily why both TP and PO4-P in the hypereutrophic Lake Donghu declined significantly since the mid-1980s when heavy cyanobacterial blooms were eliminated by the nontraditional biomanipulation (massive stocking of the filter-feeding silver and bighead carps), but also explains why TP in European lakes decreased remarkably in the spring clear-water phase with less phytoplankton during the seasonal succession of aquatic communities or when phytoplankton biomass was decreased

关键词： shallow lakes, internal P loading, algal blooms.

An approximate analytical solution for transient gas flows in a vertically fractured well of finite fracture conductivity

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Petroleum Science 2022年第6期19卷 3059-3067页

作者： Yun-Hu Lu Kang-ping Chen yan Jin Hong-Da Li Quan xie College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102200China School for Engineering of Matter Transport and EnergyArizona State UniversityTempeAZ85287-6106USA Discipline of Petroleum Engineering WA School of Mines:MineralsEnergy and Chemical EngineeringCurtin University26 Dick Perry Avenue6151KensingtonWestern AustraliaAustralia

An analytical solution in physical variable space is presented for transient gas flows during constant-rate production from a vertically-fractured well in an infinite homogeneous reservoir with finite fracture *** solution is based on the short-time asymptotic solution and a new approximate transient elliptical flow solution,which covers transient flows from the bilinear flow regime to the pseudo-radial flow *** solution covers the well-known asymptotic solutions in both short-and long-time limits of bilinear and pseudo-radial *** analytical model provides a practical and reliable engineering tool to evaluate the fractured reservoir properties,which can be programmed using a spreadsheet.

关键词： Transient gas pressure Fractured well Analytical solution

Fuzheng Huayu recipe, a traditional Chinese compound herbal medicine, attenuates renal interstitial fibrosis via targeting the miR-21/PTEN/AKT axis

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Journal of Integrative Medicine 2020年第6期18卷 505-513页

作者： Qing-lan Wang yan-yan Tao Hong-dong xie Cheng-hai Liu ping Liu Teaching&Research Department of Clinical and Classic Medicine College of Basic Medical Science.Shanghai University of Traditional Chinese MedicineShanghai 201203.China E-institute of Shanghai Municipal Education Committee Shanghai University of Traditional Chinese MedicineShanghai 210203China Institute of Liver Diseases Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 210203China

Objective: MicroRNAs(miRNAs) may be viable targets for treating renal interstitial fibrosis(RIF). Fuzheng Huayu recipe(FZHY), a traditional Chinese compound herbal medicine, is often used in China to treat fibrosis. This study sought to assess the mechanisms through which FZHY influences miRNAs to treat ***: RIF was induced in rats by mercury chloride and treated with FZHY. Hydroxyproline content,Masson’s staining and type I collagen expression were used to evaluate renal collagen *** miRNA profiles were evaluated using a miRNA microarray. Those miRNAs that were differentially expressed following FZHY treatment were identified and subjected to bioinformatic analyses. The miR-21 target gene phosphatase and tensin homolog(PTEN) expression and AKT phosphorylation in kidney tissues were assessed via Western blotting. In addition, HK-2 human proximal tubule epithelial cells were treated using angiotensin II(Ang-II) to induce epithelial-to-mesenchymal transition(EMT), followed by FZHY exposure. miR-21 and PTEN expressions were evaluated via quantitative reverse transcriptionpolymerase chain reaction(qRT-PCR), while E-cadherin and a-smooth muscle actin(a-SMA) expressions were assessed by immunofluorescent staining and qRT-PCR. Western blotting was used to assess PTEN and AKT ***: FZHY significantly decreased kidney collagen deposition, hydroxyproline content and type I collagen level. The miRNA microarray identified 20 miRNAs that were differentially expressed in response to FZHY treatment. Subsequent bioinformatic analyses found that miR-21 was the key fibrosis-related miRNA regulated by FZHY. FZHY also decreased PTEN expression and AKT phosphorylation in fibrotic kidneys. Results from in vitro tests also suggested that FZHY promoted E-cadherin upregulation and inhibited a-SMA expression in Ang-II-treated HK-2 cells, effectively reversing Ang-II-mediated EMT. We also determined that FZHY reduced miR-21 expression, increased PTEN ex

关键词： Fuzheng Huayu recipe Chinese herbal medicine Renal interstitial fibrosis miR-21 PTEN AKT microRNA

酸枣仁提取物调控miR-7b-3p/5-羟色胺1A受体表达促进骨生长

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中国组织工程研究 2025年第12期29卷 2450-2457页

作者：罗石任吴晓龙谢艳河南省洛阳正骨医院(河南省骨科医院) 河南省郑州市450000

背景:前期研究发现,酸枣仁提取物通过提高脑组织5-羟色胺1A受体(serotonin 1A receptor,5-HT1AR)表达,使之与5-羟色胺结合,延长小鼠慢波睡眠,促进生长激素的分泌,从而使骨生长。5-HT1AR作为一种蛋白质,其表达丰度受到miRNA的调控。作者... 详细信息

背景:前期研究发现,酸枣仁提取物通过提高脑组织5-羟色胺1A受体(serotonin 1A receptor,5-HT1AR)表达,使之与5-羟色胺结合,延长小鼠慢波睡眠,促进生长激素的分泌,从而使骨生长。5-HT1AR作为一种蛋白质,其表达丰度受到miRNA的调控。作者推测酸枣仁提取物可能通过miRNA调控5-HT1AR的表达从而发挥药物作用。目的:观察酸枣仁提取物通过干预小鼠脑组织中miR-7b-3p/5-HT1AR通路对骨骼生长的影响。方法:①将昆明种小鼠分为正常对照组、用药组(灌胃酸枣仁提取物0.320 mg/g),阳性对照组(灌胃酸枣仁皂甙0.013 mg/g)和酸枣仁提取物+5-HT1AR抑制剂组(灌胃酸枣仁提取物最后3 d同时每天侧脑室注射5-HT1AR选择性抑制剂P-MPPF 8μg),25 d后观察酸枣仁提取物对小鼠骨生长、血清生长激素水平及脑组织5-HT1AR表达的影响;②基因芯片法筛选由酸枣仁提取物引起的骨生长小鼠与普通小鼠脑组织差异表达的miRNAs,并通过PCR验证和双荧光素酶报告基因实验证实筛选的miR-7b-3p与5-HT1AR的调控关系;③体外培养小鼠脑皮质细胞并鉴定,利用Western blot法观察酸枣仁提取物对脑皮质细胞中5-HT1AR表达的影响;④将昆明种小鼠分为正常对照组、用药组、miR-7b-3p inhibitor组、用药+miR-7b-3p mimics组、阳性对照组,观察各组小鼠脑组织5-HT1AR表达及5-羟色胺与5-HT1AR结合活性;⑤将SD大鼠分为正常对照组、用药组、miR-7b-3p inhibitor组、用药+miR-7b-3p mimics组、阳性对照组,观察各组大鼠慢波睡眠的变化。结果与结论:①酸枣仁提取物可以促进小鼠体长、胫骨增长,促进生长激素分泌,提高脑组织5-HT1AR含量;②基因芯片筛选出差异表达的miRNAs个数为16个,其中上调有13个,下调有3个;生物信息学预测下调miR-7b-3p可以调控5-HT1AR表达,且双荧光素酶报告基因实验证实二者有直接调控关系;③酸枣仁提取物和沉默脑皮质细胞中miR-7b-3p表达可以引起5-HT1AR高表达;沉默miR-7b-3p后小鼠脑组织5-HT1AR表达、5-羟色胺与5-HT1AR结合活性及生长激素分泌均升高;过表达miR-7b-3p后小鼠脑组织5-HT1AR表达、5-羟色胺与5-HT1AR结合活性及生长激素分泌均降低;大鼠慢波睡眠期也相应延长或缩短。结果表明,酸枣仁提取物能够降低脑组织的miR-7b-3p水平,同时增加5-HT1AR的表达量。这种机制有助于延长慢波睡眠周期,并且促进生长激素的生成,对骨骼生长有积极影响,为使用酸枣仁提取物作为促进骨骼生长的潜在手段提供了科学依据。

关键词：酸枣仁提取物 miR-7b-3p 脑组织 5-羟色胺 5-羟色胺1A受体生长激素

Application of Modified Quasi-Regular Solution Model to Binary Metallurgical Molten Slag Systems

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Journal of Iron and Steel Research International 2010年第10期17卷 13-17,22页

作者： HOU yan-qing xie Gang TAO Dong-ping YU Xiao-hua Faculty of Metallurgical and Energy Engineering Kunming University of Science andTechnology Kunming 650093 Yunnan China

Modified quasi-regular solution model has been available based on the sub-regular solution model and quasiregular solution model in this article. The three parameters of this model are set by the computer-aided analysis based on the experimental data of activity at two different temperatures. Seven binary molten slag systems in the whole concentration are calculated by application of the model and the average relative error is within 10%. Ten binary molten slag systems presenting saturation concentration are also calculated, but the average relative error is bigger, especially for the systems containing acidic oxide and neutral oxide. The results show that the calculated results are superior to those calculated by application of regular solution model, sub-regular solution model and quasi-regular solution model.

关键词： activity binary molten slag modified model sub-regular solution

Theoretical Study on the Rotational Spectra of Ar-D232S Complex

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Chinese Journal of Chemical Physics 2013年第6期26卷 656-660,I0003页

作者： Jin-ping Lei yan-zi Zhou Dai-qian xie Institute of Theoretical and Computational Chemistry Key Laboratory of Mesoscopic Chemistry Schoolof Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China

We report a theoretical study on the rotational spectra of Ar-D232S. The intermolecular po- tential energy surface was transformed from our latest ab initio three-dimensional potential of Ar-H232S. The rotational energy levels and wavefunctions of the complex were calcu- lated by using the radial discrete variable representation/angular finite basis representation method and the Lanczos algorithm. The calculated rotational transition frequencies and structural parameters were found to be in good agreement with the available experimental values.

关键词： Rotational spectrum Van der Waals complex Molecular structure

A New Feature Vector Using Selected Line Spectra for Pulsar Signal Bispectrum Characteristic Analysis and Recognition

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Chinese Journal of Astronomy and Astrophysics 2007年第4期7卷 565-571页

作者： Zhen-Hua xie Lu-ping XU Guang-Ren Ni yan Wang School of Electronic Engineering Xidian University Xi＇an 710071 National Time Service Center Chinese Academy of Sciences Xi＇ an 710600

Average pulse profiles of pulsar signals are analyzed using the bispectrum technique. The result shows that there are nonlinear phase couplings between the two frequency axes of the bispectrum charts, which indicate nonlinear factors in the generation and propagation of pulsar signals. Bispectra can be used as feature vectors of pulsar signals because of their being translation invariant. A one-dimension selected line spectrum algorithm for extracting pulsar signal characteristic is proposed. Compared with selected bispectra, the proposed selected line spectra have the maximum interclass separability measurements from the point of view of the whole one-dimension feature vector. Recognition experiments on several pulsar signals received at several frequency bands are carried out. The result shows that the selected line spectrum algorithm is suitable for extracting pulsar signal characteristics and has a good classification performance.

关键词： pulsars: general-stars: magnetic fields-stars: fundamental parameters (classification)