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间断或持续PTH刺激对骨及间充质干细胞的不同分化作用

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中华医学杂志 2018年第10期98卷 781-787页

作者：张瀶曦 Deepak H. Balani Sophia Trinh henry M. Kronenberg 母义明解放军总医院内分泌科北京100853 Endocrine Unit Massachusetts General Hospital and Harvard Medical School Boston 02114 USA

目的探讨不同甲状旁腺素（PTH）给药情况下及撤药后，骨及间充质干细胞的不同分化作用机制。方法6周龄雄性C57/BL6J小鼠，基因型为SOX9－creERT/Td－Tomato/Osteocalcin－GFP，分为间断PTH刺激及撤药组（PTH 500 μg·kg^－1·d^－1，... 详细信息

目的探讨不同甲状旁腺素（PTH）给药情况下及撤药后，骨及间充质干细胞的不同分化作用机制。方法6周龄雄性C57/BL6J小鼠，基因型为SOX9－creERT/Td－Tomato/Osteocalcin－GFP，分为间断PTH刺激及撤药组（PTH 500 μg·kg^－1·d^－1，皮下注射）、持续PTH刺激及撤药组（PTH泵，80 μg·kg^－1·d^－1，速度0.25 μl/h，皮下埋入）、空白对照组及撤药对照组，共6组，每组8只。分别于给药2周及撤药2周时观察小鼠血清中钙离子浓度及骨密度，并取小鼠胫骨骨骼分别进行病理及免疫荧光染色。结果间断PTH刺激组血清钙离子浓度一过性升高，达（1.36±0.03）mmol/L。持续PTH泵刺激组血清中钙离子浓度逐渐升高，48 h达高峰[（2.33±0.03）mmol/L]，2周后恢复正常（1.12～1.27 mmol/L）。PTH刺激2周后，间断组[（0.047±0.002）g/cm2]和持续组[（0.046±0.001）g/cm2]骨密度均高于对照组[（0.044±0.001）g/cm2]，但间断组和持续组差异无统计学意义。停药2周后，三组间BMD差异无统计学意义。股骨病理可见间断组骨皮质不明显，大量的骨小梁增生，伴少量纤维组织增生；持续PTH刺激大片纤维组织增生，尤以骨皮质内侧显著，撤药后纤维化消失。间断PTH刺激后骨细胞和成骨细胞明显升高，撤药后明显下降；衬里细胞数量骤减，撤药后有所增加；破骨细胞给药及撤药后差异均无统计学意义。持续PTH刺激破骨细胞增多，衬里细胞骤减，撤药后破骨细胞和衬里细胞增加，成骨细胞减少。腓骨干骺端免疫荧光显示，间断PTH刺激组大量未分化的Td－tomato间充质干细胞，撤药后较前明显减少。持续PTH组少量未分化的Td－tomato间充质干细胞增生，撤药后较前减少。结论间断PTH刺激可通过增加未分化的间充质干细胞和成骨细胞数量，将衬里细胞转换为骨细胞和成骨细胞，进而促进骨生成；持续PTH刺激可使少量未分化的间充质干细胞、成骨细胞和骨细胞增生，伴大量纤维化增生和破骨细胞数量骤增，最终可能导致代谢性骨病，撤药后衬里细胞明显增加，或有利于代谢性骨病的缓解。

关键词：甲状旁腺素间充质干细胞骨成骨细胞破骨细胞

Targeting microthrombosis and neuroinflammation with vepoloxamer for therapeutic neuroprotection after traumatic brain injury

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Neural Regeneration Research 2018年第3期13卷 413-414页

作者： Ye Xiong Li zhang Zheng Gang zhang Asim Mahmood Michael Chopp Department of Neurosurgery Henry Ford Hospital Detroit MI USA Department of Neurology Henry Ford Hospital Detroit MI USA Department of Physics Oakland University Rochester MI USA

Traumatic brain injury （TBI）： Despite improved supportive and rehabilitative care of TBI patients, TBI remains a leading cause of death and disability worldwide. To date, no effective pharmacological treatments are available for TBI. The mechanisms underlying brain damage and repair following TBI are complex and not completely understood. Coagulopathy after TBI is frequent and an independent prognostic factor for unfavorable outcome and prognosis （Stein and Smith, 2004）. It may be amenable to treatment, and effective management of coagulopathy may protect from secondary injury and poor outcomes. Although the main challenge for TBI management is to address the risk of hypocoagulopathy with prolonged bleeding and progression of hemorrhagic lesions, the risk of hypercoagulopathy with an increased microthrombosis formation warrants investigation to reduce neurological deficits after TBI.

关键词： TBI Targeting microthrombosis and neuroinflammation with vepoloxamer for therapeutic neuroprotection after traumatic brain injury

水系锌离子电池二氧化锰正极的储能特性及机理研究进展

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精细化工 2021年第3期38卷 464-473页

作者：张华旭亨瑞刘昊廖立兵中国地质大学(北京)数理学院北京100083 中国地质大学(北京)材料科学与工程学院北京100083

水系锌离子电池在大型储能等领域具有很高的应用价值和发展前景。目前,水系锌离子电池的正极材料研究主要集中在锰基化合物(如二氧化锰、三氧化二锰、三氧化三锰等)、钒基氧化物以及普鲁士蓝类似物等材料。其中,二氧化锰具有电化学性能... 详细信息

水系锌离子电池在大型储能等领域具有很高的应用价值和发展前景。目前,水系锌离子电池的正极材料研究主要集中在锰基化合物(如二氧化锰、三氧化二锰、三氧化三锰等)、钒基氧化物以及普鲁士蓝类似物等材料。其中,二氧化锰具有电化学性能优良、储量丰富、价格低廉及安全环保等优势,成为当前最受关注的一类正极材料,近年来得到快速发展。但是,在充放电过程中,二氧化锰晶型多变且伴随其他表面反应,其反应机理复杂且存在一定争议。近两年来,随着研究的不断深入,其电化学反应机理逐渐明晰。围绕二氧化锰的晶体结构特点及其作为水系锌离子电池正极的性能,结合最新研究进展重点讨论了不同晶型二氧化锰的储能机理,并对其未来发展趋势进行了展望。

关键词：水系锌离子电池二氧化锰正极材料储能机理

Mass Transfer Characteristics of H_2 and CO in Mimicked F-T Slurry Bubble Column Reactor

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China Petroleum Processing & Petrochemical Technology 2018年第2期20卷 111-118页

作者： Wu Jianmin Sun Qiwen zhang Zongsen Yankuang Energy R&D Co. Ltd.State Key Laboratory of Coal Liquefaction and Coal Chemical Technology

The equilibrium solubilities,volumetric gas-liquid mass transfer coefficients kLa of H_2 and CO were measured as functions of temperature(298―513 K),pressure(1―3 MPa),superficial gas velocity(0.5―3 cm/s) and solid volume fraction(5%―25%) in liquid paraffin/iron-based catalyst slurry bubble column *** volumetric mass transfer coefficients kLa were obtained by measuring the dissolution rate of H_2 and *** influences of the operation conditions,such as pressure,temperature,superficial gas velocity and catalyst concentration on kLa,were *** empirical correlations were proposed to predict kLa values of H_2 and CO in liquid paraffin/solid particles slurry bubble column *** results showed that the equilibrium solubilities of H-2 and CO increased with an increasing temperature and pressure,and the solubility of CO was greater than that for H_*** was found that the equilibrium solubility can be expressed by henry's *** volumetric mass transfer coefficients of H_2 and CO were of the same order of magnitude,and increased with the increase of pressure,temperature and superficial gas *** presence of solid particles decreased kLa values of both H_2 and CO.

关键词： slurry bubble column reactor solubility volumetric mass transfer coeffcient iron-based catalyst

Chiral iminophosphorane catalyzed asymmetric henry reaction of α,β-alkynyl ketoesters

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Chinese Chemical Letters 2019年第8期30卷 1519-1522页

作者： Yanxia zhang Xin-Yan Wu Jianwei Han Key Laboratory for Advanced Materials Institute of Fine ChemicalsSchool of Chemistry&Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China Shanghai-Hong Kong Joint Laboratory in Chemical Synthesis Shanghai Institute of Organic ChemistryThe Chinese Academy of SciencesShanghai 200032China

α,β-Alkynyl ketoesters were introduced to the enantioselective henry reaction(nitroaldol condensation)with nitromethane catalyzed by tartaric acid derived chiral *** such,a variety of optically activeβ-nitro-substituted tertiary alcohols bearing alkyne moieties were obtained in good to excellent yields(42%–99%)and moderate to good level of enantiomeric excess(up to 87%ee).

关键词： Organocatalysis Iminophosphorane Nitroaldol henry reaction Alkynyl ketoesters

Exogenous application of succinic acid enhances tolerance of Larix olgensis seedling to lead stress

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Journal of Forestry Research 2018年第6期29卷 1497-1505页

作者： Jinfeng Song Hongguang zhang Chengwei Duan Xiaoyang Cui School of Forestry Northeast Forestry University Maoershan Forest Research Station Northeast Forestry University

Larix olgensis A. henry(Changbai larch) is a productive commercial species and good candidate for afforestation in northeast China. It is widely planted in lead-stressed soils which can induce oxidative damage in this plant. Increasing tolerance to lead(Pb) stress is therefore of keen interest. A greenhouse experiment was conducted to identify the biomass, physiological responses and Pb accumulation of L. olgensis seedlings to Pb stress under succinic acid(SA) application and to explore the interaction of exogenous SA applications and stress resistance. L. olgensis seedlings were planted in Pb-stressed or unstressed haplic cambisols in pots. In Pb-contaminated soils the seedlings were treated daily with concentrations of SA solutions at a rate approximately equivalent to 0, 0.04,0.2, 1.0, or 2.0 mmol kg-1of soil for 10, 20, and 30 days,respectively. Pb treatment induced damage in the seedlings and led to the inhibition of biomass accumulation in roots,stems and leaves, and a rise in Pb accumulation in fine roots and leaves. Malondialdehyde(MDA) content and electrolyte leakage in leaves significantly increased while peroxidase(POD) activities, soluble protein and photosynthetic pigment contents in leaves were all *** toxicity was promoted with increasing Pb treatment times. When Pb-stressed seedlings were exposed to SA(especially 10.0 mmol L-1 over 20 days), the physiological responses for Pb-only were reversed and the biomass of roots, stems, and leaves dramatically *** facilitated Pb uptake in fine roots and leaves but more Pb accumulated in fine roots. The results demonstrate that exogenous SA alleviates Pb-induced oxidative injuries and improves the tolerance of L. olgensis seedlings to Pb stress.

关键词： Soil Pb stress Succinic acid Larix olgensis Physiological response Pb uptake

Recent progress in copper catalyzed asymmetric henry reaction

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Chinese Chemical Letters 2018年第6期29卷 873-883页

作者： Sheng zhang Yanan Li Youguo Xu Zhiyong Wang Hefei National Laboratory for Physical Sciences at Microscale CAS Key Laboratory of Soft Matter Chemistry & Collaborative Innovation Center of SuzhouNano Science and Technology Department of Chemistry University of Science and Technology of China College of Chemistry and Pharmaceutical Engineering Nanyang Normal University

henry reaction is one of the most classical reactions to construct synthetically useful product nitro alcohol, which as a privileged skeleton is widely distributed in various pharmaceuticals. This review summarizes the recent progress of copper-catalyzed asymmetric henry reaction from 2011 to 2016. The significant progress that has been made in this area will be highlighted and some of challenges that the author believes may be hindering further progress will be revealed.

关键词： henry reaction Asymmetric catalysis Copper catalysis Nitro compounds C-C bond formation

A biofilter model for simultaneous simulation of toluene removal and bed pressure drop under varied inlet Ioadings

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Frontiers of Environmental Science & Engineering 2015年第3期9卷 554-562页

作者： Jinying XI Insun KANG Hongying HU Xian zhang Environmental Simulation and Pollution Control State Key Joint Laboratory School of Environment Tsinghua University Beijing 100084 China Graduate School at Shenzhen Tsinghua University Shenzhen 518055 China

In this study, a biofiltration model including the effect of biomass accumulation and inert biomass growth is developed to simultaneously predict the Volatile Organic Compounds （VOCs） removal and filter bed pressure drop tmder varied inlet loadings. A laboratoryscale experimental biofilter for gaseous toluene removal was set up and operated for 100 days with inlet toluene concentration ranging from 250 to 2500 mg· m^-2 According to sensitivity analysis based on the model, the VOCs removal efficiency of the biofilter is more sensitive to henry＇s constant, the specific surface area of the filter bed and the thickness of water layer, while the filter bed pressure drop is more sensitive to biomass yield coefficient and original void fraction. The calculated toluene removal efficiency and bed pressure drop satisfactorily fit the experimental data under varied inlet toluene loadings, which indicates the model in this study can be used to predict VOCs removal and bed pressure drop simultaneously. Based on the model, the effect of mass-transfer parameters on VOCs removal and the stable-run time of a biofilter are analyzed. The results demonstrate that the model can function as a good tool to evaluate the effect of biomass accumulation and optimize the design and operation of biofilters.

关键词： Volatile Organic Compounds (VOCs) biofil- ters modelling biomass accumulation pressure drop

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水稻新基因OsJT1的克隆及功能初步分析

分子植物育种 2018年第2期16卷 345-351页

作者：张小玲朱骞 Sadia Nadir henry AKrofiDoku 陈丽娟李东宣云南农业大学稻作研究所昆明650201 云南农业大学省部共建云南生物资源保护与利用国家重点实验室昆明650201 科技大学化学部本努28100 CSIR-Crops研究所库马西999064

水稻(Oryza sativa L.)生长发育与其体内的激素调节密切相关,本研究从水稻野生型黎榆B(*** *** *** B)基因组中克隆了一个与激素调节相关的新基因OsJT1。生物信息学分析表明:水稻OsJT1基因cDNA全长650 bp、编码216个氨基酸;OsJT1蛋白的... 详细信息

水稻(Oryza sativa L.)生长发育与其体内的激素调节密切相关,本研究从水稻野生型黎榆B(*** *** *** B)基因组中克隆了一个与激素调节相关的新基因OsJT1。生物信息学分析表明:水稻OsJT1基因cDNA全长650 bp、编码216个氨基酸;OsJT1蛋白的理论分子量为22.99 kD,等电点为7.68,是亲水性的稳定蛋白;OsJT1蛋白的二级结构中,9个α-螺旋,16个无规则卷曲,10个B折叠,5个β转角。本研究构建了融合表达载体(p Ca MV35S::OsJT1:EGFP),通过农杆菌介导法获得OsJT1过表达株系,性状分析表明:过表达株系的株高和结实率下降、叶宽增加,且结实率和叶片宽度与野生型差异均达到显著水平(p<0.05)。根据生物信息学及过表达转基因植株的表型分析内容,初步推断该基因可能与激素调节相关。

关键词：水稻 OsJT1 过表达生物信息学