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Amplification of an MFS Transporter Encoding Gene penT Significantly Stimulates Penicillin Production and Enhances the Sensitivity of Penicillium chrysogenum to Phenylacetic Acid 被引量:3
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作者 Jing Yang Xinxin Xu gang liu 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2012年第11期593-602,共10页
Penicillin is historically important as the first discovered drug against bacterial infections in human. Although the penicillin biosyn- thetic pathway and regulatory mechanism have been well studied in Penicillium ch... Penicillin is historically important as the first discovered drug against bacterial infections in human. Although the penicillin biosyn- thetic pathway and regulatory mechanism have been well studied in Penicillium chrysogenum, the compartmentation and molecular transport of penicillin or its precursors are still poorly understood. In search of the genomic database, more than 830 open reading frames (ORFs) were found to encode transmembrane proteins of P. chrysogenum. In order to investigate their roles on penicillin production, one of them (penT) was selected and cloned. The deduced protein ofpenTbelongs to the major facilitator superfamily (MFS) and contains 12 transmembrane spanning domains (TMS). During fermentation, the transcription of penT was greatly induced by penicillin precursors phenylacetic acid (PAA) and phenoxyacetic acid (POA). Knock-down of penT resulted in significant decrease of penicillin production, while over-expression of penT under the promoter of trpC enhanced the penicillin production. Introduction of an additional penT in the wild-type strain of P. chrysogenurn doubled the penicillin production and enhanced the sensitivity of P. chrysogenum to the penicillin precursors PAA or POA. These results indicate that penT stimulates penicillin production probably through enhancing the translocation of penicillin precursors across fungal cellular membrane. Penicillin is historically important as the first discovered drug against bacterial infections in human. Although the penicillin biosyn- thetic pathway and regulatory mechanism have been well studied in Penicillium chrysogenum, the compartmentation and molecular transport of penicillin or its precursors are still poorly understood. In search of the genomic database, more than 830 open reading frames (ORFs) were found to encode transmembrane proteins of P. chrysogenum. In order to investigate their roles on penicillin production, one of them (penT) was selected and cloned. The deduced protein ofpenTbelongs to the major facilitator superfamily (MFS) and contains 12 transmembrane spanning domains (TMS). During fermentation, the transcription of penT was greatly induced by penicillin precursors phenylacetic acid (PAA) and phenoxyacetic acid (POA). Knock-down of penT resulted in significant decrease of penicillin production, while over-expression of penT under the promoter of trpC enhanced the penicillin production. Introduction of an additional penT in the wild-type strain of P. chrysogenurn doubled the penicillin production and enhanced the sensitivity of P. chrysogenum to the penicillin precursors PAA or POA. These results indicate that penT stimulates penicillin production probably through enhancing the translocation of penicillin precursors across fungal cellular membrane. 展开更多
关键词 Penicillium chrysogenum PEN Penicillin production Phenylacetic acid MFS transporter
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鄂尔多斯盆地陇东地区太原组铝土岩系地球化学特征及其对物源的指示作用
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作者 李涵 王玉霞 +3 位作者 马占荣 周立发 刘刚 郭京哲 《天然气地球科学》 北大核心 2025年第5期916-935,共20页
鄂尔多斯盆地陇东地区铝土矿天然气勘探的成功,极大地拓宽了油气勘探领域,显示了铝土矿广阔的勘探前景,然而其物源问题尚未有定论。通过常量、微量及稀土元素地球化学分析,综合考量了构造背景、源岩特性,对铝土岩系的物源进行了详尽分... 鄂尔多斯盆地陇东地区铝土矿天然气勘探的成功,极大地拓宽了油气勘探领域,显示了铝土矿广阔的勘探前景,然而其物源问题尚未有定论。通过常量、微量及稀土元素地球化学分析,综合考量了构造背景、源岩特性,对铝土岩系的物源进行了详尽分析。研究结果表明:①陇东地区铝土岩系垂向上元素含量在不同岩性层内表现出明显的差异性,且其稳定元素的富集特征具有继承性;②太原组垂向上的铝土岩系与石英砂岩的岩性组合特征决定了其物源区具有高差小、富铝的特点;③地球化学分析显示铝土岩系母岩来自于具有岛弧性质的中酸性火成岩,而并非直接源自下伏碳酸盐岩的风化产物;④北秦岭构造带为主体的古元古代秦岭群、中元古代宽坪群,以及早古生代早期的二郎坪群等变质岩系,包括与其伴生的广泛分布的晋宁期和加里东期中酸性岩体为研究区铝土岩系主要母岩来源,华北板块南缘的新太古代太华群深变质岩系和古元古界铁洞沟组的碎屑岩等具有辅助贡献。该成果可为深入研究陇东地区太原组铝土岩成储机理及成藏模式提供借鉴。 展开更多
关键词 铝土岩系 地球化学 物源体系 太原组 陇东地区 鄂尔多斯盆地
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LW-AFC,a new formula derived from Liuwei Dihuang decoction,ameliorates behavioral and pathological deterioration via modulating the neuroendocrine-immune abnormalities in PrP-hAβPPswe/PS1^(ΔE9) transgenic mice
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作者 Jian-hui WANG Xi LEI +7 位作者 Xiao-rui CHENG Xiao-rui ZHANG gang liu Jun-ping CHENG Yi-ran XU Ju ZENG Wen-xia ZHOU Yong-xiang ZHANG 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2017年第10期1001-1001,共1页
OBJECTIVE To investigate the effect of LW-AFC,a new formula of the main active components extracted fromLiuwei Dihuang decoction,on treatment of Alzheimer disease(AD) in mouse models.METHODS After treatment LW-AFC,mic... OBJECTIVE To investigate the effect of LW-AFC,a new formula of the main active components extracted fromLiuwei Dihuang decoction,on treatment of Alzheimer disease(AD) in mouse models.METHODS After treatment LW-AFC,mice were cognitively evaluated in behavioral experiments.Neuron loss,amyloid-β(Αβ) deposition,and Αβ level were analyzed using Nissl staining,immunofluorescence,and an Alpha LISA assay,respectively.Multiplex bead analysis,a radioimmunoassay,immunochemiluminometry,and an ELISA were used to measure cytokine and hormone levels.Lymphocyte subsets were detected using flow cytometry.RESULTS LW-AFC ameliorated the cognitive impairment observed in APP/PS1 mice,including the impairment of object recognition memory,spatial learning and memory,and active and passive avoidance.In addition,LW-AFC alleviated the neuron loss in the hippocampus,suppressed Αβ deposition in the brain,and reduced the concentration of Aβ1-42 in the hippocampus and plasma of APP/PS1 mice.LW-AFC treatment also significantly decreased the secretion of corticotropin-releasing hormone and gonadotropin-releasing hormone in the hypothalamus,and adrenocorticotropic hormone,luteinizing hormone,and follicle-stimulating hormone in the pituitary.Moreover,LW-AFC increased CD8+CD28+T cells,and reduced CD4^+CD25^+Foxp3^+T cells in the spleen lymphocytes,down-regulated interleukin(IL)-1β,IL-2,IL-6,IL-23,granulocyte-macrophage colony stimulating factor,and tumor necrosis factor-α and-β,and up-regulated IL-4 and granulocyte colony stimulating factor in the plasma of APP/PS1 mice.CONCLUSION LW-AFC ameliorated the behavioral and pathological deterioration of APP/PS1 transgenic micevia the restoration of the NIM network to a greater extent than either memantineor donepezil,which supports the use of LW-AFC as a potential agent for AD therapy. 展开更多
关键词 LW-AFC Alzheimer disease PrP-h AβPPswe/PS1ΔE9 transgenic mouse cognitive behavior amyloid-β neuron loss NEUROENDOCRINE lymphocyte subset cytokine
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Phylotranscriptomic discordance is best explained by incomplete lineage sorting within Allium subgenus Cyathophora and thus hemiplasy accounts for interspecific trait transition
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作者 Zengzhu Zhang gang liu Minjie Li 《Plant Diversity》 SCIE CAS CSCD 2024年第1期28-38,共11页
The transition of traits between genetically related lineages is a fascinating topic that provides clues to understanding the drivers of speciation and diversification.Much can be learned about this process from phylo... The transition of traits between genetically related lineages is a fascinating topic that provides clues to understanding the drivers of speciation and diversification.Much can be learned about this process from phylogeny-based trait evolution.However,such inference is often plagued by genome-wide gene-tree discordance(GTD),mostly due to incomplete lineage sorting(ILS)and/or introgressive hybridization,especially when the genes underlying the traits appear discordant.Here,by collecting transcriptomes,whole chloroplast genomes(cpDNA),and population genetic datasets,we used the coalescent model to turn GTD into a source of information for ILS and employed hemiplasy to explain specific cases of apparent“phylogenetic discordance”between different morphological traits and probable species phylogeny in the Allium subg.Cyathophora.Both concatenation and coalescence methods consistently showed the same phylogenetic topology for species tree inference based on single-copy genes(SCGs),as supported by the KS distribution.However,GTD was high across the genomes of subg.Cyathophora:~27%e38.9%of the SCG trees were in conflict with the species tree.Plasmid and nuclear incongruence was also present.Our coalescent simulations indicated that such GTD was mainly a product of ILS.Our hemiplasy risk factor calculations supported that random fixation of ancient polymorphisms in different populations during successive speciation events along the subg.Cyathophora phylogeny may have caused the character transition,as well as the anomalous cpDNA tree.Our study exemplifies how phylogenetic noise can be transformed into evolutionary information for understanding character state transitions along species phylogenies. 展开更多
关键词 Hemiplasy Multispecies coalescence Lineage sorting Gene tree discordance Phylotranscriptomics Allium subg.Cyathophora
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Effects of LW-AFC,a new formula derived from Liuwei Dihuang decoction,on intestinal microbiome in senescence-accelerated mouse prone 8 strain,a mouse model of Alzheimer disease
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作者 Xiao-rui CHENG Jian-hui WANG +7 位作者 Fu-qiang YE Xiao-rui ZHANG Feng liu gang liu Ming NI Shan-yi QIAO Wen-xia ZHOU Yong-xiang ZHANG 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2017年第10期987-987,共1页
OBJECTIVE To investigate the effects of LW-AFC,a new formula derived fromLiuwei Dihuang decoction,on gut microbiota and the behavior of learning and memory of SAMP8 mice,a mouse model of Alzheimer Disease(AD),and iden... OBJECTIVE To investigate the effects of LW-AFC,a new formula derived fromLiuwei Dihuang decoction,on gut microbiota and the behavior of learning and memory of SAMP8 mice,a mouse model of Alzheimer Disease(AD),and identify the specific intestinal microbiota correlating with cognitive ability.METHODS Morris-water maze test,novel object recognition test and shuttle-box test were conducted to observe the ability of learning and memory.16S rRNA amplicon sequencing(Illumina,San Diego,CA,USA)was employed to investigate gut microbiota.RESULTS The treatment of LW-AFC improved cognitive impairments of SAMP8 mice,including spatial learning and memory ability,active avoidance response,and object recognition memory capability.Our data indicated that there were significantly 8 increased and 12 decreased operational taxonomic units(OTUs)in the gut microbiota of SAMP8 mice compared with senescence accelerated mouse resistant 1(SAMR1) strains,the control of SAMP8 mice.The treatment of LW-AFC altered 22(16 increased and 6 decreased)OTUs in SAMP8 mice and among them,15 OTUs could be reversed by LW-AFC treatment resulting in a microbial composition similar to that of SAMR1 mice.We further showed that there were7(3 negative and 4 positive correlation)OTUs significantly correlated with all the three types of cognitive abilities,at the order level,including Bacteroidales,Clostridiales,Desulfovibrionales,CW040,and two unclassified orders.LW-AFC had influences on bacterial taxa correlated with the abilities of learning and memory in SAMP8 mice and restored them to SAMR1 mice.CONCLUSION The effects of LW-AFC on improving cognitive impairments of SAMP8 mice might be via modulating intestinal microbiome and LW-AFC could be used as a potential anti-AD agent. 展开更多
关键词 Alzheimer disease LW-AFC Liuwei Dihuang decoction MICROBIOME senescence-accelerated mouse prone 8 strain
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操作系统课程实践新路径探索--全国大学生计算机系统能力大赛操作系统设计赛“区域赛”
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作者 张羽 周庆国 +5 位作者 石亮 刘国军 陈鹏飞 刘刚 宫晓利 陈咸彰 《计算机教育》 2025年第11期15-21,共7页
针对操作系统课程实践教学面临的新挑战,借助“101计划”操作系统课程虚拟教研室平台,提出一条基于“区域赛”模式的操作系统课程“做中学”实践教学新路径,具体介绍2024年操作系统设计赛“区域赛”的实施情况,为全国高校操作系统课程... 针对操作系统课程实践教学面临的新挑战,借助“101计划”操作系统课程虚拟教研室平台,提出一条基于“区域赛”模式的操作系统课程“做中学”实践教学新路径,具体介绍2024年操作系统设计赛“区域赛”的实施情况,为全国高校操作系统课程实践教学改革和计算机类专业学生系统能力评价提供参考与启示。 展开更多
关键词 操作系统 101计划 实践教学 操作系统设计赛 泛在系统能力
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LW-AFC,a new formula derived from Liuwei Dihuang decoction,ameliorates behavioral and pathological deterioration via modulating the neuroendocrineimmune system in Alzheimer disease mouse models
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作者 Jian-hui WANG Xi LEI +7 位作者 Xiao-rui CHENG Xiao-rui ZHANG gang liu Jun-ping CHENG Yi-ran XU Ju ZENG Wen-xia ZHOU Yong-xiang ZHANG 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2018年第4期303-304,共2页
OBJECTIVE Alzheimer disease(AD),the most common cause of dementia among older people,could not be prevented,halted,or reversed up till now.A large body of pharmacological study has revealed that Liuwei Dihuang(LW) pos... OBJECTIVE Alzheimer disease(AD),the most common cause of dementia among older people,could not be prevented,halted,or reversed up till now.A large body of pharmacological study has revealed that Liuwei Dihuang(LW) possesses potential therapeutic effects on AD.LW-AFC is key fractions fromLW.In the present study,we investigated the effect of LW-AFC on AD mouse models.METHODS PrP-hAβPPswe/PS1ΔE9(APP/PS1) mice and senescence-accelerated mouse prone 8 strain(SAMP8),classic AD animal models,were employed.After the treatment of LW-AFC,mice were cognitively evaluated in behavioral experiments.Neuron loss,amyloid-β(Αβ)deposition,and Αβ level were analyzed using Nissl staining,immunofluorescence,and an AlphaLISA assay,respectively.Multiplex bead analysis,a radioimmunoassay,immunochemiluminometry,and an ELISA were used to measure cytokine and hormone levels.Lymphocyte subsets were detected using fl ow cytometry.RESULTS LW-AFC ameliorated the cognitive impairment observed in APP/PS1 and SAMP8 mice,including the impairment of object recognition memory,spatial learning and memory,and active and passive avoidance.In addition,LW-AFC alleviated the neuron loss in the hippocampus,suppressed amyloid-β(Αβ) deposition in the brain,and reduced the concentration of Aβ1-42 in the hippo.campus and plasma of APP/PS1 mice.LW-AFC treatment also significantly restored the imbalance of hypothalamic-pituitary-adrenal(HPA) and hypothalamic-pituitary-gonadal(HPG) axis,enhanced the proliferation of splenocytes,corrected the disorder of lymphocyte subsets,and regulated the abnormal production of cytokine in APP/PS1 and SAMP8 mice.Effects of LW-AFC on pharmacodynamics and neuroendocrine immunomodulation network in APP/PS1 and SAMP8 mice were better than meman.tine and donepezil.CONCLUSION LW-AFC ameliorated the behavioral and pathological deterioration of AD mouse models via the restoration of the NIM network,which supports the use of LW-AFC as a potential agent for AD therapy. 展开更多
关键词 阿尔茨海默病 药理学 临床分析 药物化学
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Liuwei Dihuang Decoction improves cognitive impairments via regulating immune system in APP/PS1 transgenic mouse, a mouse model of Alzheimer disease
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作者 Xi LEI Jian-hui WANG +5 位作者 Xiao-rui CHENG Xiao-rui ZHANG gang liu Jun-ping CHENG Wen-xia ZHOU Yong-xiang ZHANG 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2018年第4期291-291,共1页
OBJECTIVE To investigate the effect and mechanisms of Liuwei Dihuang Decoction(LW) on cognition in PrP-hAβPPswe/PS1ΔE9(APP/PS1) transgenic mice.METHODS LW was adminis.trated with oral for 3 months.The locomotor acti... OBJECTIVE To investigate the effect and mechanisms of Liuwei Dihuang Decoction(LW) on cognition in PrP-hAβPPswe/PS1ΔE9(APP/PS1) transgenic mice.METHODS LW was adminis.trated with oral for 3 months.The locomotor activity test was performed to investigate the spontaneous motor activity of mice.The Morris water maze test and shuttle box test were performed to investigate the spatial learning and memory and active avoidance response respectively.The Αβ deposits and neuron loss in the hippocampus was detected by immunofluorescence staining and nissl staining respectively.The flow cytometry was employed to investigate the lymphocyte subsets of the mice.The 3 H-thymidine incorporation was performed to investigate the splenocytes proliferation.RESULTS The treatment of LW ameliorated the impairments of spatial learning and memory and active and passive avoidance in APP/PS1 mice.The administration of LW alleviated neuron loss in the brain,suppressed amyloid-β(Αβ) deposits in the hippocampus of APP/PS1 mice.The treatment of LW significantly increased ConAand LPS-induced proliferation of splenocytes,increased CD3+ T cells and CD19+ B cells in the spleen lymphocytes and reduced Gr1+ cells in APP/PS1 mice.CONCLUSION This data indicated the adminis.tration of LW ameliorated behavioral and pathological deterioration via regulating immune function. 展开更多
关键词 六味地黄汤 中医 治疗方法 临床分析
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6S理念在高校仪器分析化学教学实验室规范化管理中的应用 被引量:1
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作者 王琳琳 刘刚 +2 位作者 柴春笑 路庆明 马莹 《大学化学》 2025年第10期186-193,共8页
实验室作为实验教学的重要场所,其整体环境对学生的实验学习和习惯养成具有潜移默化的引导作用。本文主要介绍了山东大学化学省级实验教学中心仪器分析化学实验室结合自身特点与需求,在6S(整理(SEIRI)、整顿(SEITON)、清扫(SEISO)、清洁... 实验室作为实验教学的重要场所,其整体环境对学生的实验学习和习惯养成具有潜移默化的引导作用。本文主要介绍了山东大学化学省级实验教学中心仪器分析化学实验室结合自身特点与需求,在6S(整理(SEIRI)、整顿(SEITON)、清扫(SEISO)、清洁(SEIKETSU)、素养(SHITSUKE)、安全(SECURITY))管理上的具体实施方法与成效。 展开更多
关键词 6S 仪器分析 化学教学实验室 管理
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吴茱萸碱通过下调RhoA表达抑制胶质母细胞瘤细胞迁移侵袭增殖和凋亡 被引量:1
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作者 王明山 刘纲 +2 位作者 李斌 王鑫 刘伟 《中国肿瘤临床》 北大核心 2025年第10期494-499,共6页
目的:分析吴茱萸碱(evodiamine,Evo)对胶质母细胞瘤(glioblastoma,GBM)细胞迁移、侵袭、增殖和凋亡的影响及相关分子机制的探讨。方法:回顾性分析2022年2月至2024年2月于山东第二医科大学附属医院手术切除的26例GBM组织和10例正常脑组织... 目的:分析吴茱萸碱(evodiamine,Evo)对胶质母细胞瘤(glioblastoma,GBM)细胞迁移、侵袭、增殖和凋亡的影响及相关分子机制的探讨。方法:回顾性分析2022年2月至2024年2月于山东第二医科大学附属医院手术切除的26例GBM组织和10例正常脑组织,分析GBM组织中RhoA表达情况及与GBM患者临床病理特征的关系。以A-172细胞及U-118细胞为研究对象,将实验分为对照组(空载质粒)、Evo组(空载质粒+30μmol/L Evo)、RhoA组(pcDNA3.1-RhoA)和Evo+RhoA组(30μmol/L Evo+pcDNA3.1-RhoA)。采用CCK-8、平板集落形成实验、流式细胞术、划痕愈合和Transwell侵袭实验分析Evo对A-172及U-118细胞恶性表型的作用;Western blot检测Evo对细胞中RhoA、ROCK、MMP-2及CyclinD1蛋白表达的影响。结果:RhoA在GBM组织中高表达。与对照组比较,Evo组可显著抑制A-172及U-118细胞的增殖、集落形成、迁移与侵袭,诱导细胞凋亡,并抑制细胞中RhoA、ROCK、MMP-2及CyclinD1的蛋白表达(P<0.05);而Evo+RhoA组则可逆转Evo对GBM细胞增殖、迁移、侵袭、凋亡能力的影响,同时逆转对GBM细胞相关蛋白表达的抑制作用。结论:吴茱萸碱可抑制胶质母细胞瘤细胞的增殖、迁移及侵袭能力,促进细胞凋亡,其作用机制可能与下调RhoA的表达有关。 展开更多
关键词 吴茱萸碱 胶质母细胞瘤 RHOA 迁移 侵袭 增殖 凋亡
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Efficacy of recombinant human thrombopoietin in patients with acute-on-chronic liver failure and thrombocytopenia:A prospective,open-label study 被引量:1
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作者 gang liu Fei Tang +6 位作者 Tao Wang Jun-Qing Yan Feng-Hui Li Fu-Shuang Ha Xu Zhang Li Jing Jing Liang 《World Journal of Gastroenterology》 2025年第14期61-70,共10页
BACKGROUND Patients with acute-on-chronic liver failure(ACLF)have a high mortality rate,poor prognosis,and often experience concurrent thrombocytopenia and bleeding events.AIM To evaluate the efficacy and safety of re... BACKGROUND Patients with acute-on-chronic liver failure(ACLF)have a high mortality rate,poor prognosis,and often experience concurrent thrombocytopenia and bleeding events.AIM To evaluate the efficacy and safety of recombinant human thrombopoietin(rhTPO)in patients with ACLF with concomitant severe thrombocytopenia.METHODS This was a prospective,open-label study.We assigned 70 ACLF patients with severe thrombocytopenia into the rhTPO group and control group,with 35 patients in each group.Patients in the rhTPO group received subcutaneous injections of rhTPO at a dose of 15000 IU/day for 7 consecutive days,while patients in the control group did not receive rhTPO treatment.The primary endpoint was the proportion of patients with platelet count>50×10^(9)/L on day 14.RESULTS The proportion of patients with platelet count>50×10^(9)/L on day 14 was 60.7%in the rhTPO group,which was significantly higher than that(12.0%)in the control group(P<0.001).The platelet count in the rhTPO group on day 14 was 64×10^(9)/L,exceeding the baseline of 28×10^(9)/L.Compared to the control group,the rhTPO group exhibited a significant increase in platelet count from baseline(P<0.05).Model for end-stage liver disease score,albumin level and international normalized ratio improved significantly from baseline on day 14 after rhTPO injection.The concentrations of serum thrombopoietin and hepatocyte growth factor in the rhTPO group after 7 days were 143.7 and 195.4 pg/mL,respectively,showing a significant increase from baseline(P<0.05).Eight(22.9%)patients had bleeding events in the control group compared with four(11.4%)in the rhTPO group.The incidence of 90-day mortality was also higher in the control group(6,17.1%)than that in the rhTPO group(3,8.6%).CONCLUSION rhTPO significantly increased the platelet count in ACLF patients with thrombocytopenia and reduce the occurrence of bleeding events,with a good safety profile. 展开更多
关键词 Recombinant human thrombopoietin Acute-on-chronic liver failure THROMBOCYTOPENIA Hepatocyte growth factor PROGNOSIS
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Visual synapse based on reconfigurable organic photovoltaic cell 被引量:1
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作者 Xiangrong Pu Fan Shu +2 位作者 Qifan Wang gang liu Zhang Zhang 《Journal of Semiconductors》 2025年第2期105-112,共8页
The hierarchical and coordinated processing of visual information by the brain demonstrates its superior ability to min-imize energy consumption and maximize signal transmission efficiency.Therefore,it is crucial to d... The hierarchical and coordinated processing of visual information by the brain demonstrates its superior ability to min-imize energy consumption and maximize signal transmission efficiency.Therefore,it is crucial to develop artificial visual synapses that integrate optical sensing and synaptic functions.This study fully leverages the excellent photoresponsivity proper-ties of the PM6:Y6 system to construct a vertical photo-tunable organic memristor and conducts in-depth research on its resis-tive switching performance,photodetection capability,and simulation of photo-synaptic behavior,showcasing its excellent per-formance in processing visual information and simulating neuromorphic behaviors.The device achieves stable and gradual resis-tance change,successfully simulating voltage-controlled long-term potentiation/depression(LTP/LTD),and exhibits various photo-electric synergistic regulation of synaptic plasticity.Moreover,the device has successfully simulated the image percep-tion and recognition functions of the human visual nervous system.The non-volatile Au/PM6:Y6/ITO memristor is used as an artificial synapse and neuron modeling,building a hierarchical coordinated processing SLP-CNN cascade neural network for visual image recognition training,its linear tunable photoconductivity characteristic serves as the weight update of the net-work,achieving a recognition accuracy of up to 93.4%.Compared with the single-layer visual target recognition model,this scheme has improved the recognition accuracy by 19.2%. 展开更多
关键词 organic memristor visual synapse neuromorphic computing PM6:Y6 image recognition
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Research on rock crack contact model considering linked substances based on particle flow method 被引量:1
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作者 Fukun Xiao Kai Xie +3 位作者 Lei Shan gang liu Lianchong Li Fedotova Iuliia 《International Journal of Mining Science and Technology》 2025年第4期553-571,共19页
The models constructed by particle flow simulation method can effectively simulate the heterogeneous substance characteristics and failure behaviors of rocks.However,existing contact models overlook the rock cracks,an... The models constructed by particle flow simulation method can effectively simulate the heterogeneous substance characteristics and failure behaviors of rocks.However,existing contact models overlook the rock cracks,and the various simulation methods that do consider cracks still exhibit certain limitations.In this paper,based on Flat-Joint model and Linear Parallel Bond model,a crack contact model considering linked substance in the crack is proposed by splitting the crack contact into two portions:linked portion and unlinked portion for calculation.The new contact model considers the influence of crack closure on the contact force-displacement law.And a better compressive tensile strength ratio(UCS/T)was obtained by limiting the failure of the contact bond to be solely controlled by the contact force and moment of the linked portion.Then,by employing the FISH Model tool within the Particle Flow Code,the contact model was constructed and verified through contact force–displacement experiments and loading-unloading tests with cracked model.Finally,the contact model was tested through simulations of rock mechanics experiments.The results indicate that the contact model can effectively simulate the axial and lateral strain laws of rocks simultaneously and has a relatively good reproduction of the bi-modularity of rocks. 展开更多
关键词 Crack closure Contact model Compaction stage Initial effective modulus Lateral strain
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Effect of Al on microstructure and mechanical properties of cast CrCoNi medium-entropy alloy 被引量:7
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作者 Qiang Hu Fu-chu liu +5 位作者 Qian-lu Fan Hui Du gang liu Guang-hua Wang Zi-tian Fan and *Xin-wang liu 《China Foundry》 SCIE 2018年第4期253-262,共10页
Cast CrCoNiAIx (x=0-1.2) medium-entropy alloys (MEAs) were produced by arc melting and flip cast to investigate the alloying effect of AI addition on the microstructure, phase constituent and mechanical properties... Cast CrCoNiAIx (x=0-1.2) medium-entropy alloys (MEAs) were produced by arc melting and flip cast to investigate the alloying effect of AI addition on the microstructure, phase constituent and mechanical properties. The crystal structure changes from an initial face-centered cubic (FCC) to duplex FCC and body-centered cubic (BCC) and finally a single BCC with increasing AI content. In the duplex region, FCC and BCC phases form under a eutectic reaction in the interdendrite region. In the single BCC region, the dendrites transform to ordered B2 and disordered A2 BCC phases resulting from spinodal decomposition. Corresponding to their phase constituents, yield strength increases accompanied with an elongation reduction with increasing AI addition. A very interesting phenomenon of very weak ordered FCC (001) spots appearing in AI-0.4 alloy was observed, indicating a local ordering of FCC phase. The changes of fracture surfaces after the tensile deformation are also corresponding to the variations in mechanical properties. 展开更多
关键词 medium-entropy alloy microstructure mechanical properties Al addition
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连续性纯合片段在畜禽基因组研究中的应用 被引量:9
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作者 刘刚 孙飞舟 +2 位作者 朱芳贤 冯海永 韩旭 《遗传》 CAS CSCD 北大核心 2019年第4期304-317,共14页
随着高通量SNP芯片技术的快速发展和测序成本的大幅降低,SNP基因芯片和基因组重测序等技术被广泛地应用于畜禽基因组研究中。在基因组某一段区域内,当一定数量和一定密度的SNPs表现为纯合时,可以判定该区域存在连续性纯合片段(runs of h... 随着高通量SNP芯片技术的快速发展和测序成本的大幅降低,SNP基因芯片和基因组重测序等技术被广泛地应用于畜禽基因组研究中。在基因组某一段区域内,当一定数量和一定密度的SNPs表现为纯合时,可以判定该区域存在连续性纯合片段(runs of homozygosity, ROH)。目前,连续性纯合片段已经逐渐成为分析畜禽群体近交程度、遗传结构等方面的重要指标之一。但是,ROH计算应用的评价标准还相对匮乏。本文系统介绍了连续性纯合片段的发展历史、原理、鉴定方法以及在畜禽群体结构解析、基因组功能分析和种畜禽品质检测等方面的应用情况,以期为畜禽遗传资源保种区和保种场在遗传多样性等动态监测方面提供参考。 展开更多
关键词 高通量测序技术 连续性纯合片段 群体结构 基因组功能 遗传缺陷
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Source models for the 2016 Mw6.0 Hutubi earthquake, Xinjiang,China: A possible reverse event 被引量:5
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作者 gang liu Xuejun Qiao +3 位作者 Wei Xiong YU Zhou Zhaosheng Nie Chuanjia Xia 《Geodesy and Geodynamics》 2017年第5期311-318,共8页
South and north-dipping nodal planes from the U.S. Geological Survey moment tensor solution were used to invert global teleseismic body waves to reveal the source rupture process of the December 8, 2016, Mw6.0 Hutubi ... South and north-dipping nodal planes from the U.S. Geological Survey moment tensor solution were used to invert global teleseismic body waves to reveal the source rupture process of the December 8, 2016, Mw6.0 Hutubi earthquake. The results show that a compact pattern is the main feature of this event for only one main slip zone located at the hypocenter for both models, The slip distributions are dominated by a nearly pure-thrust fault, and there is no apparent surface rupture. The inversion revealed that the slip zone extends 10 km along strike and 12 km along dip. The released total seismic moment was about 9.0 -1017 Nm, corresponding to a magnitude of Mw6.0. It is difficult to solve for a best-fit rupture plane due to the sample slip pattern without obvious rupture directivity. This makes the far- field teleseismic data not sensitive enough to determine the fault geometric parameters. The source model of the reverse north-dipping plane fits well with the observed waveforms, and the results of the aftershock relocation outline a trend of north-dipping profiles, indicating the possibility of a reverse event. The inverted normal fault beneath the Qigu fold, interpreted by geological and seismic studies, may be the seismogenic fault for this reverse event. 展开更多
关键词 Source rupture processMw6.0 Hutubi earthquakeReverse eventInverted normal fault Qigu fold
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准噶尔盆地南缘西段下部成藏组合油气藏形成过程--以独山子背斜独山1井为例 被引量:5
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作者 刘刚 李建忠 +3 位作者 齐雪峰 朱明 袁波 庞志超 《天然气地球科学》 CAS CSCD 北大核心 2021年第7期1009-1021,共13页
准噶尔盆地南缘西段下部成藏组合油气资源丰富,勘探程度低,厘清成藏过程对该区油气勘探具有重要的指导意义。利用流体包裹体岩相观察、均一温度测试、储集层定量荧光技术、全扫描荧光分析等实验方法,结合原油和天然气的物理及地球化学特... 准噶尔盆地南缘西段下部成藏组合油气资源丰富,勘探程度低,厘清成藏过程对该区油气勘探具有重要的指导意义。利用流体包裹体岩相观察、均一温度测试、储集层定量荧光技术、全扫描荧光分析等实验方法,结合原油和天然气的物理及地球化学特征,以及单井埋藏史模拟、生排烃史恢复、构造演化史分析等成藏要素配置关系分析,系统研究了盆地南缘独山子背斜下部成藏组合的形成过程。研究表明:①独山子背斜头屯河组储集层中存在2期烃类包裹体,第一期为黄色荧光的液烃包裹体,烃类以低成熟—成熟原油为主,该期包裹体丰度低,油气充注强度较低,未形成规模油气藏;第二期为发蓝色荧光的成熟—高成熟轻质油包裹体,包裹体丰度较高。②独山1井头屯河组部分层段(6416 m、6493 m)储层颗粒表面吸附烃浓度较高,表明头屯河组存在油层,吸附烃以低密度轻质油为主;储集层中也可见沥青及沥青质较高的稠油,指示油气藏形成后遭受过一定程度破坏调整。③独山子背斜头屯河组油气充注最早始于古近纪早期,但油气充注量有限,并未形成规模油气藏,直至中新世时期(5~3 Ma),烃源岩生排烃强度显著增强,油气快速充注并形成油气藏,之后受到喜马拉雅构造运动的影响,油气藏遭受不同程度破坏改造,油气沿断裂向浅层溢散,早期的古油藏呈现为不同烃类饱和度的残留油层,部分层段饱和度较高(6416.9~6417.4 m、6493~6493.5 m),推测试油可获工业油流。 展开更多
关键词 成藏期次 成藏过程 流体包裹体 颗粒定量荧光 下部成藏组合 准噶尔盆地南缘
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典型环境因素对聚合物基复合材料力学行为影响的研究现状与进展 被引量:7
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作者 高禹 孙成博 +4 位作者 高博闻 王柏臣 于祺 刘刚 包建文 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2018年第5期177-182,共6页
随着聚合物基复合材料在飞行器结构中的大量应用,复合材料的力学行为演变规律及损伤失效问题越来越受到人们的高度关注。环境损伤效应作为材料在服役过程中不可避免的问题,使深入研究环境因素对复合材料力学行为的影响具有重要的理论与... 随着聚合物基复合材料在飞行器结构中的大量应用,复合材料的力学行为演变规律及损伤失效问题越来越受到人们的高度关注。环境损伤效应作为材料在服役过程中不可避免的问题,使深入研究环境因素对复合材料力学行为的影响具有重要的理论与工程价值。文中对近年来不同环境因素对聚合物基复合材料力学行为的影响进行了综述,重点探讨了在高温、湿热、真空热循环条件下,聚合物基复合材料力学行为的研究结果与状况,以期为聚合物基复合材料在新型飞行器上的应用提供有益的参考。 展开更多
关键词 聚合物基复合材料 高温 湿热 真空热循环 力学行为
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混合现实技术辅助全腹腔镜下胰十二指肠切除术 被引量:7
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作者 刘刚 李晓莉 +4 位作者 龚连生 陈子华 邹明浩 周文炫 彭瑛 《中国内镜杂志》 2020年第7期72-75,共4页
目的探讨应用混合现实技术辅助全腹腔镜下胰十二指肠切除术(LPD)的可行性。方法选取中南大学湘雅医院肝胆胰外科收治的十二指肠肿瘤患者1例,术前检查完善,无绝对手术禁忌,拟行LPD。术前利用患者腹部CT对患者体表及靶病变进行三维重建及... 目的探讨应用混合现实技术辅助全腹腔镜下胰十二指肠切除术(LPD)的可行性。方法选取中南大学湘雅医院肝胆胰外科收治的十二指肠肿瘤患者1例,术前检查完善,无绝对手术禁忌,拟行LPD。术前利用患者腹部CT对患者体表及靶病变进行三维重建及手术规划,术中应用混合现实(MR)技术导航手术入路、明辨重要解剖结构、辅助进行LPD,顺利完成手术。结果患者恢复顺利,无明显并发症,术后2周顺利出院。结论MR技术对手术部位解剖结构重建及定位精确,有望为普外科手术带来更多的发展和进步,应用前景良好。 展开更多
关键词 胰十二指肠切除术 腹腔镜手术 混合现实 发展前景
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Overview of mosquito control based on RNA interference
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作者 Shi-Wen Duan gang liu Yin-Liang Wang 《Life Research》 2025年第3期74-77,共4页
RNA interference(RNAi)is a post-transcriptional gene-silencing technique induced by the introduction of double-stranded RNA(dsRNA)or small interfering RNA(siRNA)[1].RNAi-based strategies have been extensively applied ... RNA interference(RNAi)is a post-transcriptional gene-silencing technique induced by the introduction of double-stranded RNA(dsRNA)or small interfering RNA(siRNA)[1].RNAi-based strategies have been extensively applied in the treatment of human diseases and crop protection against insect pests[2-4].With the availability of the full genome sequences of major mosquito vectors,RNAi has become increasingly used as a novel means of mosquito control[5]. 展开更多
关键词 mosquito control DSRNA treatment human diseases RNA interference insect pests small interfering rna sirna rnai based crop protection rna interference rnai
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