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Transfer of the zp3a gene results in changes in egg adhesiveness and buoyancy in transgenic zebrafish
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作者 Yu-Qing Cao Yong-Xin Wang +5 位作者 yan zhao Jia Zhang Xian He Ping Xie Jun Chen Yu-Hua Sun 《Zoological Research》 SCIE CAS CSCD 2023年第2期259-268,共10页
Reproductive strategies and spawning habits play key roles in the evolution of endemic East Asian cyprinids.However,the molecular mechanisms underlying the regulation of spawning habits are not well understood.We rece... Reproductive strategies and spawning habits play key roles in the evolution of endemic East Asian cyprinids.However,the molecular mechanisms underlying the regulation of spawning habits are not well understood.We recently identified zona pellucida(Zp) as the top differentially expressed protein between East Asian cyprinids that produce adhesive and semi-buoyant eggs,suggesting that Zp protein may play important roles in the regulation of egg type.In this work,we generated transgenic zebrafish in which oocyte-specific expression of zp genes from rare minnow(Gobiocypris rarus),an East Asian cyprinid laying adhesive eggs,was driven by a zebrafish zp3.2 gene promoter.We found that the transgenic eggs obtained partial adhesiveness and exhibited alteration in hydration and buoyancy.Abnormal metabolism of vitellogenin(VTG) may contribute to enhanced hydration and/or buoyancy.Our work shows that expression of the exogenous zp3a gene from an adhesiveegg producing fish is sufficient to induce changes in both egg adhesiveness and buoyancy in zebrafish,emphasizing the important role of zp genes in the regulation of spawning habits.Our results thus provide new insights into how endemic East Asian cyprinids may have adapted to the Yangtze river-lake system via changes in spawning habits. 展开更多
关键词 Zona pellucida protein ADHESIVE BUOYANCY HYDRATION Egg envelope
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个人信息保护的行政规制:实践检视及完善路径
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作者 叶战备 闫钊 《中共山西省委党校学报》 2024年第2期82-86,共5页
行政规制在个人信息保护方面发挥着重要作用,有利于弥补民法规制与刑法规制对个人信息保护的不足,较大程度地防止相关主体对个人信息权益的侵害。然而,实践中个人信息保护的行政规制存在立法内容的涵盖性有待加强、监督制度的有效性有... 行政规制在个人信息保护方面发挥着重要作用,有利于弥补民法规制与刑法规制对个人信息保护的不足,较大程度地防止相关主体对个人信息权益的侵害。然而,实践中个人信息保护的行政规制存在立法内容的涵盖性有待加强、监督制度的有效性有待提高、处罚制度的严谨性有待强化、救济程序的规范性有待提升等方面的不足,应通过完善现行立法内容、优化行政监督体制、调适行政处罚机制、改进行政救济程序等路径对个人信息保护的行政规制予以完善。 展开更多
关键词 个人信息 个人信息保护 行政规制 信息数据
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发酵乳制品风味形成机制及优化控制研究进展
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作者 王娜 夏秀华 +4 位作者 李晶 徐旨润 严钊 杨光 赵敏 《中国乳品工业》 CAS 北大核心 2024年第3期43-50,共8页
发酵乳制品营养丰富,深受广大消费者喜爱。风味是发酵乳制品最重要的感官属性之一,但乳制品在发酵过程中极易产生不良风味,影响发酵乳制品的风味品质,因此充分了解发酵乳制品中风味物质的转化过程及形成机制对优化风味有重要意义。基于... 发酵乳制品营养丰富,深受广大消费者喜爱。风味是发酵乳制品最重要的感官属性之一,但乳制品在发酵过程中极易产生不良风味,影响发酵乳制品的风味品质,因此充分了解发酵乳制品中风味物质的转化过程及形成机制对优化风味有重要意义。基于相关研究,综合论述了发酵乳制品风味形成途径的重要研究进展,阐述了风味优化控制的重要技术措施。通过对相关文献的梳理,指出发酵乳制品风味形成过程中碳水化合物代谢、脂肪分解、蛋白质水解等关键生化转化途径,以及通过靶向筛选和鉴定产香乳酸菌、优化加工条件、应用基因工程等优化风味的方法。未来可就乳酸菌的开发及在调控风味生成的潜在代谢机制等方面展开深入研究。 展开更多
关键词 发酵乳制品 风味 机制 优化 控制
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功能性乳制品功能特性及潜在机制研究进展
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作者 王娜 谢强 +5 位作者 陈小红 宋涛 徐旨润 严钊 杨光 赵敏 《食品与发酵工业》 CAS CSCD 北大核心 2024年第3期345-356,共12页
近年来,消费者对食品健康益处的认识不断提高,这极大程度地推动了功能性食品的发展。功能性乳制品是一类新兴的乳制品,在全球功能性食品市场中占据着重要地位。该文主要综述了功能性乳制品的分类、功能特性(调节肠道健康、提高认知能力... 近年来,消费者对食品健康益处的认识不断提高,这极大程度地推动了功能性食品的发展。功能性乳制品是一类新兴的乳制品,在全球功能性食品市场中占据着重要地位。该文主要综述了功能性乳制品的分类、功能特性(调节肠道健康、提高认知能力、改善肥胖、降低糖尿病和心血管疾病的发生率、维持骨骼及口腔健康等)及其发挥重要功效的潜在机制,以期为功能性乳制品的开发和行业发展提供参考和借鉴。 展开更多
关键词 功能性乳制品 来源 分类 功能特性 机制
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内蒙古某矿床不同铁矿石类型中稀土矿化特征
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作者 严钊 郭宾 +6 位作者 孟文祥 苑星宇 洪国敏 贾瑞敏 侯新宇 田畸 杨进军 《现代矿业》 CAS 2024年第4期41-45,50,共6页
为明确内蒙古某矿床不同铁矿石类型与稀土矿化特征的关系,基于矿区内海量、系统的勘查工程所揭露的岩/矿石类型以及稀土、铁的基本分析数据,在已有的铁矿石分类基础上,进一步对铁和稀土资源进行分类。共划分出6种不同类型的铁-稀土矿石... 为明确内蒙古某矿床不同铁矿石类型与稀土矿化特征的关系,基于矿区内海量、系统的勘查工程所揭露的岩/矿石类型以及稀土、铁的基本分析数据,在已有的铁矿石分类基础上,进一步对铁和稀土资源进行分类。共划分出6种不同类型的铁-稀土矿石类型,并对各类型中稀土的成矿规模、强度及其在空间上的分布特征进行刻画。研究表明,不同类型的铁矿石中稀土成矿性和富集强度存在较大差异,稀土在浅部成矿富集规模大于深部;稀土与铁的矿化在空间产出上存在一定的相关性,但并非同体系流体成矿作用形成。 展开更多
关键词 矿石类型 铁-稀土矿石 矿化特征 成矿作用
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Genome-wide association study of grain micronutrient concentrations in bread wheat
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作者 Yongchao Hao Fanmei Kong +8 位作者 Lili Wang Yu zhao Mengyao Li Naixiu Che Shuang Li Min Wang Ming Hao Xiaocun Zhang yan zhao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1468-1480,共13页
Bread wheat(Triticum aestivum)is a staple food crop worldwide.The genetic dissection of important nutrient traits is essential for the biofortification of wheat to meet the nutritional needs of the world's growing... Bread wheat(Triticum aestivum)is a staple food crop worldwide.The genetic dissection of important nutrient traits is essential for the biofortification of wheat to meet the nutritional needs of the world's growing population.Here,45,298 single-nucleotide polymorphisms(SNPs)from 55K chip arrays were used to genotype a panel of 768 wheat cultivars,and a total of 154 quantitative trait loci(QTLs)were detected for eight traits under three environments by genome-wide association study(GWAS).Three QTLs(qMn-3B.1,qFe-3B.4,and qSe-3B.1/qFe-3B.6)detected repeatedly under different environments or traits were subjected to subsequent analyses based on linkage disequilibrium decay and the P-values of significant SNPs.Significant SNPs in the three QTL regions formed six haplotypes for qMn-3B.1,three haplotypes for qFe-3B.4,and three haplotypes for qSe-3B.1/qFe-3B.6.Phenotypic analysis revealed significant differences among haplotypes.These results indicated that the concentrations of several nutrient elements have been modified during the domestication of landraces to modern wheat.Based on the QTL regions,we identified 15 high-confidence genes,eight of which were stably expressed in different tissues and/or developmental stages.TraesCS3B02G046100 in qMn-3B.1 and TraesCS3B02G199500 in qSe-3B.1/qFe-3B.6 were both inferred to interact with metal ions according to the Gene Ontology(GO)analysis.TraesCS3B02G199000,which belongs to qSe-3B.1/qFe-3B.6,was determined to be a member of the WRKY gene family.Overall,this study provides several reliable QTLs that may significantly affect the concentrations of nutrient elements in wheat grain,and this information will facilitate the breeding of wheat cultivars with improved grain properties. 展开更多
关键词 bread wheat nutritional element GWAS DOMESTICATION HAPLOTYPE
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Metagenomic analysis revealing the metabolic role of microbial communities in the free amino acid biosynthesis of Monascus rice vinegar during fermentation
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作者 Hang Gao Jian Zhang +4 位作者 Li Liu Lijun Fu yan zhao Germán Mazza Xin Zhang 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期2317-2326,共10页
Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic netw... Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic network on FAA biosynthesis remains unclear.Through metagenomic analysis,this work aimed to elucidate the roles of microbes in FAA biosynthesis during Monascus rice vinegar fermentation.Taxonomic profiles from functional analyses showed 14 dominant genera with high contributions to the metabolism pathways.The metabolic network for FAA biosynthesis was then constructed,and the microbial distribution in different metabolic pathways was illuminated.The results revealed that 5 functional genera were closely involved in FAA biosynthesis.This study illuminated the metabolic roles of microorganisms in FAA biosynthesis and provided crucial insights into the functional attributes of microbiota in vinegar fermentation. 展开更多
关键词 Monascus rice vinegar Metagenomic analysis Free amino acid synthesis Metabolic pathway Microbial distribution
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伊马替尼治疗胃肠道间质瘤耐药的相关分子机制研究进展
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作者 赵燕 王昱昊 +1 位作者 王娟 杨建军 《中国肿瘤临床》 CAS CSCD 北大核心 2024年第4期197-202,共6页
研究胃肠道间质瘤(gastrointestinal stromal tumor,GIST)伊马替尼耐药的机制,开发新的治疗靶点和治疗方案,对改善GIST患者的长期预后具有重要意义。本文从GIST的分子特征、伊马替尼耐药机制、非编码RNA、溶酶体、关键蛋白和成纤维细胞... 研究胃肠道间质瘤(gastrointestinal stromal tumor,GIST)伊马替尼耐药的机制,开发新的治疗靶点和治疗方案,对改善GIST患者的长期预后具有重要意义。本文从GIST的分子特征、伊马替尼耐药机制、非编码RNA、溶酶体、关键蛋白和成纤维细胞生长因子2(fibroblast growth factor-2,FGF-2)等方面对GIST伊马替尼耐药机制的研究进行了综述。研究表明,不同的耐药机制网络之间是相互联系的。伊马替尼治疗和联合抑制多种耐药机制有望成为GIST治疗的新选择。此外,基于耐药机制的识别实施个体化治疗将为伊马替尼耐药的GIST患者提供新的辅助治疗选择,从而延缓GIST的进展。 展开更多
关键词 胃肠道间质瘤 伊马替尼 耐药 分子机制
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Exploring the relationship between red blood cell levels and emotional regulation through the miR191-Riok3-Mxi1 pathway
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作者 Da Zhang Xiaoqing Zhang +2 位作者 Li yang yan zhao Xingang Hu 《Journal of Traditional Chinese Medical Sciences》 CAS 2024年第1期101-110,共10页
Objective:To assess emotional fluctuations,physical and mental health status,and indicators closely related to red blood cells,such as RIO kinase 3(Riok3),MAX interactor 1(Mxi1),and microRNA 191(miR191),in participant... Objective:To assess emotional fluctuations,physical and mental health status,and indicators closely related to red blood cells,such as RIO kinase 3(Riok3),MAX interactor 1(Mxi1),and microRNA 191(miR191),in participants with different levels of red blood cells.Methods:Participants who underwent physical examinations at Dongfang Hospital between April and October 2019 were divided into healthy,blood deficiency,and anemia groups(30 individuals in the healthy and blood deficiency group respectively,and 13 in the anemia group).The physical and mental conditions of the participants were evaluated through questionnaires,and emotional fluctuations were assessed through an emotion-inducing experiment,in which participants watched video segments designed to induce specific emotions.Relative expression levels of miR191,Riok3,and Mxi1 from venous blood samples were also determined.Results:The main psychological factors identified in the anemia and blood deficiency groups were obsessive-compulsive symptoms,depression,anxiety,and other negative emotions.Relative gene expression levels indicated that miR191 was upregulated and Riok3 and Mxi1 were downregulated in both the blood deficiency and anemia groups.Regarding the emotional score of disgust on video stage,the main effect was significant(F=335.58,P<.001),which showed that watching the three videos caused participants to have a dominant emotion,and there is a difference on group(F=5.35,P=.01),with higher disgust scores in the anemia and blood deficiency groups.The symptoms of blood deficiency and anemia,such as weakness in limbs were significantly negatively correlated with Riok3 and Mxi1 expression(r=-0.38 and-0.31 respectively),but was significantly positively correlated with miR191 expression(r=0.29).Conclusion:We determined that a close relationship exists between red blood cell levels and emotional status.Our findings suggest that individuals with anemia and blood deficiency are more likely to experience psychological problems and negative emotions,particularly disgust.We also demonstrate that emotional regulation is related to mir191-Riok3-Mxi1 pathway activity,identifying these pathway components are potential targets for genetic therapies in combination with psychological therapy. 展开更多
关键词 ANEMIA Blood deficiency Emotional regulation miR191-Riok3-Mxi1 pathway Emotion-inducing experiments
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Self-consistent and precise measurement of time-dependent radiative albedo of gold based on specially symmetrical triple-cavity Hohlraum
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作者 Zhiyu Zhang yang zhao +19 位作者 Xiaoying Han Liling Li Bo Qing Lifei Hou Yulong Li YuXue Zhang Huan Zhang Xiangming Liu Bo Deng Gang Xiong Min Lv Tuo Zhu Chengwu Huang Tianming Song yan zhao Yingjie Li Lu Zhang Xufei Xie Jiyan Zhang Jiamin yang 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第3期57-64,共8页
A self-consistent and precise method to determine the time-dependent radiative albedo,i.e.,the ratio of the reemission flux to the incident flux,for an indirect-drive inertial confinement fusion Hohlraum wall material... A self-consistent and precise method to determine the time-dependent radiative albedo,i.e.,the ratio of the reemission flux to the incident flux,for an indirect-drive inertial confinement fusion Hohlraum wall material is proposed.A specially designed symmetrical triple-cavity gold Hohlraum is used to create approximately constant and near-equilibrium uniform radiation with a peak temperature of 160 eV.The incident flux at the secondary cavity waist is obtained from flux balance analysis and from the shock velocity of a standard sample.The results agree well owing to the symmetrical radiation in the secondary cavity.A self-consistent and precise time-dependent radiative albedo is deduced from the reliable reemission flux and the incident flux,and the result from the shock velocity is found to have a smaller uncertainty than that from the multi-angle flux balance analysis,and also to agree well with the result of a simulation using the HYADES opacity. 展开更多
关键词 PRECISE cavity RADIATIVE
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Efficiency and safety of Tripterygium Wilfordii Hook F for IgA nephropathy: an update systematic review and meta-analysis
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作者 Zi-Yi He Hui-Chuan Tian +2 位作者 yan zhao Rui-Yu Mou Hong-Wei Yuan 《Pharmacology Discovery》 2024年第2期24-31,共8页
Background:Immunoglobulin A Nephropathy(IgAN)currently stands as the most prevalent primary chronic glomerular disease worldwide.The latest guidelines recommend the application of renin-angiotensin system inhibitors(R... Background:Immunoglobulin A Nephropathy(IgAN)currently stands as the most prevalent primary chronic glomerular disease worldwide.The latest guidelines recommend the application of renin-angiotensin system inhibitors(RASi)in conjunction with corticosteroids for the treatment of IgAN patients exhibiting persistent proteinuria of≥1 g/d.However,numerous randomized controlled trials(RCTs)have revealed a heightened risk of adverse events associated with corticosteroid treatment.Multi-glycoside of Tripterygium wilfordii Hook.f.(GTW),a traditional Chinese medicine(TCM),has been employed in the treatment of Chronic Kidney Disease(CKD)for an extensive period.Recent years have witnessed an increasing number of RCTs providing evidence supporting the effectiveness of GTW therapy in IgAN.Despite this,there remains a paucity of systematic reviews on the application of GTW therapy for IgAN.Consequently,this study undertakes a systematic review to assess the clinical efficacy and safety of GTW therapy,aiming to elucidate the role of GTW therapy in the treatment of IgAN.Methods:To collect relative information of randomized controlled trials(RCTs)of GTW in the treatment of IgAN,we searched for theses and dissertations publicized before April 10,2023,in PubMed,Embase,the Cochrane Library,China National Knowledge Infrastructure(CNKI),Wanfang Data knowledge service platform(Wanfang Data),Chinese Scientific Journal Database(VIP),and Clinical Trial.The language limitation is English and Chinese.Independently,two reviewers performed literature screening,data extraction,and quality evaluation,and the meta-analysis was carried out with RevMan 5.4 and StataSE 15.0 software.Results:21 RCTs involving 1,405 Chinese patients were included.Compared to ACEI/ARB alone or in combination,GTW with RASi or alone reduced 24 h-Upro,ALB,Scr,GFR,BUN,CD4+,VEGF,ET-1,and improved clinical efficacy.However,no associations were found for TC,Ccr,and adverse events due to limited literature.Conclusion:This study highlights that Multi-glycoside of Tripterygium wilfordii Hook.f.(GTW)exhibits potential in safeguarding renal function and preserving the integrity of the basement membrane in patients with Immunoglobulin A Nephropathy(IgAN).Consequently,GTW emerges as a promising therapeutic option for individuals with IgAN.Nevertheless,it is crucial to acknowledge the limitations stemming from insufficient methodology and a small sample size,which currently obscure the relationships between certain clinical variables,such as total cholesterol(TC)and creatinine clearance(Ccr).Therefore,the substantiation of our findings necessitates more rigorous and expansive trials to enhance the robustness and generalizability of the results. 展开更多
关键词 TRIPTERYGIUM IgA nephropathy systematic review META-ANALYSIS
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农地制度创新“缓解撂荒”与“加剧非粮化”双向效应研究--以西南山区“三变”改革为例 被引量:3
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作者 韩德军 闫照 宋洋 《中国土地科学》 CSCD 北大核心 2023年第9期73-84,共12页
研究目的:探索农地制度创新--“三变”改革(资源变资产、资金变股金、农民变股东)对西南山区耕地撂荒与非粮化双向影响效应,为构建差别化的农地保护政策提供参考。研究方法:理论分析、双重差分模型。研究结果:(1)“三变”改革具有“缓... 研究目的:探索农地制度创新--“三变”改革(资源变资产、资金变股金、农民变股东)对西南山区耕地撂荒与非粮化双向影响效应,为构建差别化的农地保护政策提供参考。研究方法:理论分析、双重差分模型。研究结果:(1)“三变”改革具有“缓解撂荒”和“加剧非粮化”的双向效应,二者对耕地保护作用相反但基本持平,总体上不影响粮食安全。(2)“三变”改革对改革区“缓解撂荒”和“加剧非粮化”具有持续动态影响,并随着改革深入越来越显著。(3)“三变”改革主要借助土地流转集中而推动适度规模经营、提升农业机械化水平而发展现代农业、释放农业劳动力而促进产业融合发展等多种途径改变耕地利用状态。研究结论:鼓励农地制度创新盘活撂荒耕地,以有效保护耕地。在确保粮食安全基础上,采取因地制宜措施应对耕地非粮化趋势,并在农业经营实践中通过科学政策评估有效确定耕地撂荒和非粮化的最优均衡点。 展开更多
关键词 撂荒 非粮化 农地制度创新 “三变”改革 双重差分模型
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肝胆肿瘤中肿瘤特异性CircRNA衍生抗原肽的鉴定
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作者 Wenwen Wang Lili Ma +14 位作者 Zheng Xing Tinggan Yuan Jinxia Bao yanjing Zhu Xiaofang zhao yan zhao Yali Zong yani Zhang Siyun Shen Xinyao Qiu Shuai yang 王红阳 高栋 王鹏 陈磊 《Engineering》 SCIE EI CAS CSCD 2023年第3期159-170,共12页
基于肿瘤抗原的免疫治疗的应用受到验证免疫原性肽稀缺性的阻碍。本研究旨在研究环状RNA(circRNA)在肝胆肿瘤类器官中作为肿瘤抗原肽新来源的潜力。使用RNA测序(RNA-seq)和基于算法的评分工具,预测3950个翻译的肿瘤特异性环状RNA在27个... 基于肿瘤抗原的免疫治疗的应用受到验证免疫原性肽稀缺性的阻碍。本研究旨在研究环状RNA(circRNA)在肝胆肿瘤类器官中作为肿瘤抗原肽新来源的潜力。使用RNA测序(RNA-seq)和基于算法的评分工具,预测3950个翻译的肿瘤特异性环状RNA在27个类器官中产生18971个抗原肽。从抗原格局来看,11个氨基酸长度(mer)肽和人白细胞抗原(HLA)-A结合肽具有最高的免疫原性相关评分。在分析的3/5类器官中,有13个预测抗原肽通过质谱(MS)免疫肽组学被直接确认为HLA-A、HLA-B和HLA-C(HLA-ABC)结合肽。在流式细胞术和酶联免疫吸附试验(ELISA)中,由HLA-ABC分子呈递的circRNA衍生的肿瘤特异性肽刺激CD8(CD8)T细胞,显示CD107a干扰素γ(IFNγ)共表达和IFNγ分泌增加。免疫原性环状RNA衍生肽诱导的靶向类器官的细胞毒性T细胞活性在杀伤实验中得到验证。值得注意的是,来自circTBC1D15的抗原肽YGFNEILKK不仅被认为是类器官的HLA-ABC呈递肽,而且还显著降低了肿瘤类器官的存活率。本研究的发现强调了产生肿瘤抗原的一个关键亚群,这对靶向肿瘤特异性circRNA具有重要意义。 展开更多
关键词 Tumor antigen Patient-derived hepatobiliary tumor organoid Circular RNA Mass-spectrometry-based immunopeptidomics
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行政规制视角下未成年人的网络安全保护 被引量:2
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作者 叶战备 闫钊 《青少年学刊》 2023年第4期46-55,共10页
结合《未成年人保护法》《未成年人网络保护条例(征求意见稿)》等相关法律的内容来看,对于未成年人网络安全保护当中的行政规制途径主要体现在规制主体、规制实施、规制问责三个要素层面。但在当前对于未成年人网络安全保护中行政规制... 结合《未成年人保护法》《未成年人网络保护条例(征求意见稿)》等相关法律的内容来看,对于未成年人网络安全保护当中的行政规制途径主要体现在规制主体、规制实施、规制问责三个要素层面。但在当前对于未成年人网络安全保护中行政规制的实施仍面临诸如规制主体不全面、规制实施困难等问题。究其原因,是因为当前未成年人网络保护中的行政规制治理体系不够完善,法律制度的设定与适用存在价值失衡。为此,可以考虑通过推进网络保护上位专项立法、完善监督制度设计等措施补足未成年人网络安全保护面临的短板,同时加强与多方的共同合作,完善未成年人网络安全保护中的行政规制路径。 展开更多
关键词 未成年人 网络保护 网络治理 行政规制 网络安全
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二步骤回采采场顶板拱架模型及充填接顶率优化
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作者 陶明 赵岩 过江 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2023年第6期1893-1905,共13页
为了探究深部矿山采空区内充填体的合理接顶率,以二步骤回采矿山为例,应用三铰拱力学模型推导回采过程中具有不同接顶率的采空区顶板的应力表达式,并结合数值模拟分析接顶率对采场顶板应力状态的影响。结果表明,竖向应力影响矿房和矿柱... 为了探究深部矿山采空区内充填体的合理接顶率,以二步骤回采矿山为例,应用三铰拱力学模型推导回采过程中具有不同接顶率的采空区顶板的应力表达式,并结合数值模拟分析接顶率对采场顶板应力状态的影响。结果表明,竖向应力影响矿房和矿柱采场顶板的应力状态,而水平应力主要影响矿房采场顶板的应力状态。矿房采场充填接顶率对矿柱采场顶板自稳平衡拱的形成有较大的影响。在冬瓜山铜矿开采过程中,现场实际充填接顶率约为80%,实现了矿产资源安全、稳定的连续回采。 展开更多
关键词 拱形力学模型 充填接顶率 顶板稳定性 数值模拟 二步骤回采
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我国少数民族学前儿童国家通用语言研究现状与趋势--基于CiteSpace Ⅴ的可视化知识图谱分析
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作者 马亚玲 赵燕 张紫云 《西北成人教育学院学报》 2023年第6期84-91,共8页
学前教育是终身学习的开端,依据语言发展规律,提高学前儿童尤其是少数民族学前儿童国家通用语言教育质量,对于铸牢中华民族共同体意识具有重要意义,也是实现推普脱贫和乡村振兴“从娃娃抓起”、切实阻断贫困代际传递的起点性民生工程,... 学前教育是终身学习的开端,依据语言发展规律,提高学前儿童尤其是少数民族学前儿童国家通用语言教育质量,对于铸牢中华民族共同体意识具有重要意义,也是实现推普脱贫和乡村振兴“从娃娃抓起”、切实阻断贫困代际传递的起点性民生工程,是多民族国家认同建构的基础性工程,是民族地区发展进步的必由之路。基于此,文章采用CiteSpace Ⅴ数据分析软件,对CNKI数据库中近二十年来与少数民族学前儿童国家通用语言相关的研究文献进行梳理和分析,绘制知识图谱,以直观、清晰的方式呈现我国近二十年来少数民族学前儿童国家通用语言研究现状,以期为我国少数民族学前儿童国家通用语言研究的理论和实践提供参考。 展开更多
关键词 国家通用语言 民族地区学前儿童 研究趋势
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输电塔倒塌失效模式和主材角钢加固方法研究 被引量:1
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作者 李军阔 郜帆 +4 位作者 刘春城 王丽欢 任亚宁 颜召 姜涛 《自然灾害学报》 CSCD 北大核心 2023年第5期139-148,共10页
为了提高服役期输电塔抵御极端气象灾害的能力,保证输电线路的安全稳定运行,以220 kV典型输电塔为例,利用有限元方法对其进行了抗风极限承载力研究,分析强风作用下输电塔的倒塌机理和破坏模式。针对输电塔的失效模式,提出了一种输电塔... 为了提高服役期输电塔抵御极端气象灾害的能力,保证输电线路的安全稳定运行,以220 kV典型输电塔为例,利用有限元方法对其进行了抗风极限承载力研究,分析强风作用下输电塔的倒塌机理和破坏模式。针对输电塔的失效模式,提出了一种输电塔无损加固方案,通过建立不同长细比主材角钢构件的有限元模型,对加固前后主材的轴压承载力进行了数值模拟,并对输电塔整塔薄弱部位主材进行了加固设计,研究了加固后输电塔的极限抗风承载力。研究表明,加固后的主材角钢承载力大幅提升,最高可达37.2%。输电塔的薄弱部位主材加固后的局部刚度提升较大,输电塔的塔顶位移和最大应力与未加固前相比均显著降低,铁塔极限承载力大幅提升,输电塔的设计重要性系数由1.15提升至1.35,提出的加固方法可为同类型输电塔的抗风加固设计提供重要参考。 展开更多
关键词 输电塔 失效模式 多尺度方法 加固技术 极限承载力
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Mesenchymal stem cell-derived exosomes regulate microglia phenotypes:a promising treatment for acute central nervous system injury 被引量:4
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作者 Yu-yan Liu Yun Li +8 位作者 Lu Wang yan zhao Rui Yuan Meng-Meng yang Ying Chen Hao Zhang Fei-Hu Zhou Zhi-Rong Qian Hong-Jun Kang 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第8期1657-1665,共9页
There is growing evidence that long-term central nervous system(CNS)inflammation exacerbates secondary deterioration of brain structures and functions and is one of the major determinants of disease outcome and progre... There is growing evidence that long-term central nervous system(CNS)inflammation exacerbates secondary deterioration of brain structures and functions and is one of the major determinants of disease outcome and progression.In acute CNS injury,brain microglia are among the first cells to respond and play a critical role in neural repair and regeneration.However,microglial activation can also impede CNS repair and amplify tissue damage,and phenotypic transformation may be responsible for this dual role.Mesenchymal stem cell(MSC)-derived exosomes(Exos)are promising therapeutic agents for the treatment of acute CNS injuries due to their immunomodulatory and regenerative properties.MSC-Exos are nanoscale membrane vesicles that are actively released by cells and are used clinically as circulating biomarkers for disease diagnosis and prognosis.MSC-Exos can be neuroprotective in several acute CNS models,including for stroke and traumatic brain injury,showing great clinical potential.This review summarized the classification of acute CNS injury disorders and discussed the prominent role of microglial activation in acute CNS inflammation and the specific role of MSC-Exos in regulating pro-inflammatory microglia in neuroinflammatory repair following acute CNS injury.Finally,this review explored the potential mechanisms and factors associated with MSCExos in modulating the phenotypic balance of microglia,focusing on the interplay between CNS inflammation,the brain,and injury aspects,with an emphasis on potential strategies and therapeutic interventions for improving functional recovery from early CNS inflammation caused by acute CNS injury. 展开更多
关键词 acute CNS injury central nervous system inflammation exosome immune regulation mesenchymal stem cell mesenchymal stem cell-derived exosomes(MSC-Exos) microglia activation microglia phenotypic transformation molecular mechanism neuroinflammation
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电沉积法制备Ni-Cu合金镀层及其性能表征
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作者 闫曌 金辉 +2 位作者 李继东 王一雍 王和明 《热加工工艺》 北大核心 2023年第10期91-95,共5页
采用电沉积法制备Ni-Cu合金镀层,以增强不锈钢的抗氧化及耐蚀能力。以电沉积速率为依据,利用正交实验法获得最佳工艺参数;通过高温氧化和电化学方法表征镀层性能。结果表明:影响Ni-Cu合金镀层性能的主次因素为电流密度>硼酸浓度>... 采用电沉积法制备Ni-Cu合金镀层,以增强不锈钢的抗氧化及耐蚀能力。以电沉积速率为依据,利用正交实验法获得最佳工艺参数;通过高温氧化和电化学方法表征镀层性能。结果表明:影响Ni-Cu合金镀层性能的主次因素为电流密度>硼酸浓度>温度。最佳参数为:温度60℃、硼酸浓度10 g/L、电流密度5 A/dm^(2)。Ni-Cu合金镀层以其良好的抗氧化性及耐蚀性可有效保护不锈钢基体。 展开更多
关键词 不锈钢 Ni-Cu合金镀层 抗氧化性 耐蚀性
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Epitaxially Grown Ru Clusters-Nickel Nitride Heterostructure Advances Water Electrolysis Kinetics in Alkaline and Seawater Media 被引量:2
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作者 Jiawei Zhu Ruihu Lu +7 位作者 Wenjie Shi Lei Gong Ding Chen Pengyan Wang Lei Chen Jinsong Wu Shichun Mu yan zhao 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第2期81-89,共9页
The epitaxial heterostructure can be rationally designed based on the in situ growth of two compatible phases with lattice similarity,in which the modulated electronic states and tuned adsorption behaviors are conduci... The epitaxial heterostructure can be rationally designed based on the in situ growth of two compatible phases with lattice similarity,in which the modulated electronic states and tuned adsorption behaviors are conducive to the enhancement of electrocatalytic activity.Herein,theoretical simulations first disclose the charge transfer trend and reinforced inherent electron conduction around the epitaxial heterointerface between Ru clusters and Ni_(3)N substrate(cRu-Ni_(3)N),thus leading to the optimized adsorption behaviors and reduced activation energy barriers.Subsequently,the defectrich nanosheets with the epitaxially grown cRu-Ni_(3)N heterointerface are successfully constructed.Impressively,by virtue of the superiority of intrinsic activity and reaction kinetics,such unique epitaxial heterostructure exhibits remarkable bifunctional catalytic activity toward electrocatalytic OER(226 mV@20 mA cm^(−2))and HER(32 mV@10 mA cm^(−2))in alkaline media.Furthermore,it also shows great application prospect in alkaline freshwater and seawater splitting,as well as solar-to-hydrogen integrated system.This work could provide beneficial enlightenment for the establishment of advanced electrocatalysts with epitaxial heterointerfaces. 展开更多
关键词 alkaline water electrolysis bifunctional electrocatalyst epitaxial heterostructure seawater electrolysis solar-to-hydrogen integrated system
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