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头孢菌素药物发展和头孢洛扎工艺开发历程

应用技术学报 2023年第3期23卷 255-264页

作者：王育盛南昌大学化学学院南昌330031

在过去的50年里,全球批准上市50多种头孢菌素药物,几乎占所有批准的抗菌药物的一半。主要阐述了抗菌药物研发面临的问题和抗菌药物研发进展,并回顾了头孢菌素合成路线变更历程和头孢菌素药物历史发展过程。头孢洛扎是一种头孢菌素类肠... 详细信息

在过去的50年里,全球批准上市50多种头孢菌素药物,几乎占所有批准的抗菌药物的一半。主要阐述了抗菌药物研发面临的问题和抗菌药物研发进展,并回顾了头孢菌素合成路线变更历程和头孢菌素药物历史发展过程。头孢洛扎是一种头孢菌素类肠外抗生素。其硫酸盐分子式为C_(23)H_(31)N_(12)O_(8)S_(2)^(+)·HSO_(4)^(–)。与头孢菌素类的其他成员一样,头孢洛扎是通过抑制青霉素结合蛋白(PBPs)发挥杀菌作用,从而抑制细胞壁合成,随后细胞死亡。

关键词：抗菌药物抗生素头孢菌素 β-内酰胺酶抑制剂头孢洛扎工艺发展

Theoretical and experimental investigations on single-atom catalysis:Pt1/FeOx for water-gas shift reaction Shan-Fei wang1,§,Yangyang Li2,3,§,Haiyan wang1,Jin-Xia Liang1(✉),Chun Zhu1

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Nano Research 2024年第9期17卷 8627-8637页

作者： Shan-Fei wang Yangyang Li Haiyan wang Jin-Xia Liang Chun Zhu Botao Qiao School of Chemistry and Chemical Engineering Guizhou UniversityGuiyang 550025China CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China

Oxide-supported metal single-atom catalysts(SACs)have exhibited excellent catalytic performance for water-gas shift(WGS)***,we report the single-atom catalyst Pt1/FeOx exhibits excellent medium temperature catalytic performance for WGS reactions by the density functional theory(DFT)calculations and experimental *** calculations indicate that H_(2)O molecules are easily dissociated at oxygen vacancies,and the formed*OH and*O are adsorbed on Pt1 single atoms and the adjacent O atoms,*** studying four possible reaction mechanisms,it is found that the optimal WGS reaction pathway is proceeded along the carboxyl mechanism(pathway III),in which the formation of*COOH intermediates can promote the stability of Pt1/FeOx SAC and the easier occurrence of WGS *** energy barrier of the rate-determining step during the entire reaction cycle is only 1.16 eV,showing the high activity for the medium temperature WGS reaction on Pt1/FeOx SAC,which was verified by experimental ***,the calculated turnover frequencies(TOFs)of CO_(2)and H_(2)formation on Pt1/FeOx at 610 K(337℃)can reach up to 1.14×10^(-3)s^(-1)·site^(-1)through carboxyl *** this work,we further expand the application potential of Pt1/FeOx SAC in WGS reaction.

关键词： water-gas shift(WGS)reaction single-atom catalyst(SAC) density functional theory(DFT) thermocatalysis

BNmf-Si3N4w/Si3N4复合材料的制备与性能

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复合材料学报 2022年第9期39卷 4375-4383页

作者：崔雪峰赵凯王玉生叶昉成来飞西北工业大学超高温结构复合材料重点实验室西安710072

为制备一种介电性能和力学性能优异的高温透波材料,采用凝胶注模(GC)结合先驱体浸渍裂解(PIP)工艺制备了BN-SiN/SiN复合材料。研究了浸渍裂解次数及BN含量对复合材料的力学性能与介电性能的影响。结果表明:(1)随着PIP循环次数增加,复合... 详细信息

为制备一种介电性能和力学性能优异的高温透波材料,采用凝胶注模(GC)结合先驱体浸渍裂解(PIP)工艺制备了BN-SiN/SiN复合材料。研究了浸渍裂解次数及BN含量对复合材料的力学性能与介电性能的影响。结果表明:(1)随着PIP循环次数增加,复合材料的密度增大,气孔率降低,氮化硅基体逐渐形成三维网络结构包裹在复相微米增强体周围,复合材料力学性能提升;(2)当BN含量从4vol%增加到12vol%时,弯曲强度从175.5 MPa降低到139.3 MPa,断裂韧性从2.36 MPa·m增加到2.73 MPa·m,介电常数从3.62下降到3.25,介电损耗角正切从0.012下降到0.007;(3) BN-SiN/SiN复合材料的强韧化机制主要为裂纹分叉、裂纹偏转及BNmf及SiN的拔出,三种机制有效降低主裂纹对复合材料的损害。

关键词：凝胶注模先驱体浸渍裂解透波复合材料介电性能力学性能

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眼科新进展 2022年第1期42卷 1-5页

作者：王海燕张剑平王雨生西安市人民医院(西安市第四医院) 陕西省眼科医院陕西省西安市710004 空军军医大学西京医院眼科全军眼科研究所陕西省西安市710032

新生血管性年龄相关性黄斑变性(nAMD)常双眼先后发病,一眼发病后如何保持对侧眼有用的视功能与患者的生活质量密切相关。因此,监测nAMD患者对侧眼的发病情况就尤为重要。近年,远景学院(Vision Academy)的眼底病专家发起了“当前监测nAM... 详细信息

新生血管性年龄相关性黄斑变性(nAMD)常双眼先后发病,一眼发病后如何保持对侧眼有用的视功能与患者的生活质量密切相关。因此,监测nAMD患者对侧眼的发病情况就尤为重要。近年,远景学院(Vision Academy)的眼底病专家发起了“当前监测nAMD患者对侧眼的观念和方法”专家共识,该共识提出早期发现nAMD患者对侧眼脉络膜新生血管的重要性,并对目前的监测方法进行了分析,推荐每3~4个月进行一次对侧眼的检查,并鼓励利用家用技术和设备进行监测,以期早期发现、及时治疗。

关键词：年龄相关性黄斑变性脉络膜新生血管眼底影像检查监测方法

A neural mA pathway regulates behavioral aggregation in migratory locusts

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Science China Life Sciences 2024年

作者： Xianliang Huang Qing Li Yanan Xu Ang Li Shanzheng wang yusheng Chen Chunrui Zhang Xia Zhang Hailin wang Cong Lü Baofa Sun Shaoqin Li Le Kang Bing Chen Beijing Institute of Genomics Chinese Academy of Sciences College of Plant Science and Technology Huazhong Agricultural University State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of Sciences School of Life Science Institutes of Life Science and Green Development Hebei University Institute of Health Sciences Anhui University State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

RNA N6-methyladenosine(m6A), as the most abundant modification of messenger RNA, can modulate insect behaviors, but its specific roles in aggregation behaviors remain unexplored. Here, we conducted a comprehensive molecular and physiological characterization of the individual components of the methyltransferase and demethylase in the migratory locust Locusta migratoria. Our results demonstrated that METTL3, METTL14 and ALKBH5 were dominantly expressed in the brain and exhibited remarkable responses to crowding or isolation. The individual knockdown of methyltransferases(i.e., METTL3 and METTL14) promoted locust movement and conspecific attraction, whereas ALKBH5 knockdown induced a behavioral shift toward the solitary phase. Furthermore, global transcriptome profiles revealed that m6A modification could regulate the orchestration of gene expression to fine tune the behavioral aggregation of locusts. In summary, our in vivo characterization of the m6A functions in migratory locusts clearly demonstrated the crucial roles of the m6A pathway in effectively modulating aggregation behaviors.

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某肿瘤专科医院伦理委员会初审能力现状分析及提升策略研究

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临床医药实践 2024年第3期33卷 234-236页

作者：吕永强贾海霞夏志卿田学智王育生康金秀李育民余红梅米悦阎敬华张振杰李媛杨晓棠山西省肿瘤医院中国医学科学院肿瘤医院山西医院山西医科大学附属肿瘤医院山西太原030013 山西医科大学第二医院山西太原030001 山西医科大学山西太原030001

目的:通过伦理委员会初审能力现状分析,提出改善伦理审查能力的策略。方法:收集临床试验项目初审受理、会审、批件日期及重审项目审查意见,利用审查等待耗时、批准耗时及受理到批件耗时反映审查效率,通过主审会审意见一致率及既往批件... 详细信息

目的:通过伦理委员会初审能力现状分析,提出改善伦理审查能力的策略。方法:收集临床试验项目初审受理、会审、批件日期及重审项目审查意见,利用审查等待耗时、批准耗时及受理到批件耗时反映审查效率,通过主审会审意见一致率及既往批件与重审意见一致率反映审查能力一致性。结果:2020年—2022年临床试验项目数及Ⅰ,Ⅱ期项目占比逐年增多,复审率逐年下降(χ^(2)=12.74,P0.05)。结论:山西省肿瘤医院伦理委员会审查能力逐年提高,但仍有诸多不足之处,增加会审频数、实现电子信息化管理、加强培训、增加专职工作人员、实现伦理互认等措施势在必行。

关键词：伦理委员会临床试验审查效率审查质量提升策略

面向恢复决策的新型电力系统恢复目标重要度统一评估

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电力系统自动化 2024年第10期48卷 42-53页

作者：薛峰王昊昊薛禹胜南瑞集团有限公司(国网电力科学研究院有限公司) 江苏省南京市211106

在大停电发生后,如何在恢复过程中充分利用有限的可用容量快速恢复更有价值的恢复目标是电力系统快速恢复供电、减少停电损失的关键问题。充分利用新型电力系统中高占比新能源电源的恢复容量,提出了一种基于新型电力系统恢复目标重要度... 详细信息

在大停电发生后,如何在恢复过程中充分利用有限的可用容量快速恢复更有价值的恢复目标是电力系统快速恢复供电、减少停电损失的关键问题。充分利用新型电力系统中高占比新能源电源的恢复容量,提出了一种基于新型电力系统恢复目标重要度统一评估的恢复决策方法。首先,面向待恢复新能源电源的重要度评估,建立了考虑时空相关性的新能源电源多时步期望序列场景生成方法。其次,考虑储能和柔性负荷的主动协同能力,基于恢复净收益对待恢复独立电源、电源集群和变电站母线等恢复目标建立了重要度统一评估方法,揭示了恢复阶段本质为源网荷协同恢复次序优化结果的特例。然后,以电网恢复方案的期望净收益最大化为目标,建立了面向新型电力系统的源网荷统一协调恢复控制优化模型。最后,基于IEEE 118节点算例系统验证了所提方法可以在恢复过程中进行恢复目标重要度的动态评估,从而有效引导恢复容量的高效分配,最大化恢复收益。

关键词：恢复控制新型电力系统恢复目标重要度评估电源集群

FUNDAMENTAL GROUPS OF CLOSED POSITIVELY CURVED MANIFOLDS WITH ALMOST DISCRETE ABELIAN GROUP ACTIONS

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Acta Mathematica Scientia 2010年第1期30卷 203-207页

作者：王雨生 School of Mathematical Sciences(& Laboratory of Mathematics and Complex Systems) Beijing Normal University

Let M be a closed n-manifold of positive sectional curvature. Assume that M admits an effective isometrical T1× Zpk-action with p prime. The main result of the article n＋1 for n 〉 5, then there exists a positive constant p（n）, is that ifk=lforn=3or k〉 n＋1/4 for n≥5,then there exists a positive constant p（n）,depending only on n, such that π1 （M） is cyclic if p ≥ p（n）.

关键词： fundamental groups positive sectional curvature group actions

Rice Bran-derived Peptide KF-8 Attenuates Dexamethasone-induced Myopathy in Caenorhabditis elegans by Regulating Locomotion-related Genes

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Food Science and Human Wellness 2024年

作者： Yixin Wu Jianqiang wang Fang Huang Yajuan Chen Qinlu Lin Zhongxu Chen Zhigang Liu Yao Jiang Wenqing Xie Hengzhen Li yusheng Li Ying Liang National Clinical Research Center for Geriatric Disorders Xiangya Hospital Central South University Molecular Nutrition Branch National Engineering Research Center of Rice and By-product Deep Processing College of Food Science and Engineering Central South University of Forestry and Technology Laboratory of Functional Chemistry and Nutrition of Food College of Food Science and Engineering Northwest A&F University The Key Lab of Non-wood Forest Cultivation and Protection of Education Ministry The Key Lab of Non-wood Forest Products of Forestry Ministry Forestry Institute Central South University of Forestry & Technology Department of Orthopedics Xiangya Hospital Central South University

Background and aims: Dexamethasone is a common glucocorticoid medication with adverse effects that can cause muscle atrophy， but no drug intervention has been approved or recommended for this condition. KF-8 is a rice bran-derived anti-oxidant peptide that extends the life span of Caenorhabditis elegans. Methods: We established a C. elegans model of dexamethasone-induced myopathy to evaluate the potential therapeutic effects of KF-8 in this model. C. elegans muscle function was assessed in terms of locomotory behaviors including crawling， swimming， burrowing， pharyngeal pumping， and head swing. Muscle actin filament integrity was evaluated using fluorescence imaging. The molecular mechanisms of KF-8 were investigated using transcriptome sequencing， qRT-PCR， RNA interference， and western blot analysis. Results: Dexamethasone disrupted actin filaments in the striated muscles of the body wall and inhibited C. elegans crawling， swimming， burrowing， pharyngeal pumping， and head swing. KF-8 reversed the actin filament disruption and locomotor dysfunction induced by dexamethasone. Transcriptome sequencing， pathway enrichment， and qRT-PCR analyses revealed that KF-8 regulated the locomotion-related genes W04G5.10， vha-12， and ddr-1， as well as age-1 (the catalytic subunit ortholog of PI3K)， and akt1. RNA interference， conducted using a genetically engineered E. coli HT115 strain as a food source， confirmed age-1 as a key regulator of locomotor function of C. elegans. Further mechanistic studies with C2C12 myotubes showed that KF-8 regulated the IRS-PI3K-Akt pathway， the master regulator of protein synthesis and degradation. Conclusion: Together， these findings suggest that KF-8 protects against dexamethasone-induced myopathy in C. elegans by regulating locomotion-related genes and the IRS-PI3K-Akt pathway.

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