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Clinical outcome and prognostic factors of T4N0M0 colon cancer after R0 resection:A retrospective study 被引量:1
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作者 Bang Liu Zhao-Xiong Zhang +3 位作者 Xin-Yang Nie Wei-Lin Sun Yong-Jia Yan Wei-Hua Fu 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第5期1869-1877,共9页
BACKGROUND Paradoxically,patients with T4N0M0(stage II,no lymph node metastasis)colon cancer have a worse prognosis than those with T2N1-2M0(stage III).However,no previous report has addressed this issue.AIM To screen... BACKGROUND Paradoxically,patients with T4N0M0(stage II,no lymph node metastasis)colon cancer have a worse prognosis than those with T2N1-2M0(stage III).However,no previous report has addressed this issue.AIM To screen prognostic risk factors for T4N0M0 colon cancer and construct a prognostic nomogram model for these patients.METHODS Two hundred patients with T4N0M0 colon cancer were treated at Tianjin Medical University General Hospital between January 2017 and December 2021,of which 112 patients were assigned to the training cohort,and the remaining 88 patients were assigned to the validation cohort.Differences between the training and validation groups were analyzed.The training cohort was subjected to multi-variate analysis to select prognostic risk factors for T4N0M0 colon cancer,followed by the construction of a nomogram model.RESULTS The 3-year overall survival(OS)rates were 86.2%and 74.4%for the training and validation cohorts,respectively.Enterostomy(P=0.000),T stage(P=0.001),right hemicolon(P=0.025),irregular review(P=0.040),and carbohydrate antigen 199(CA199)(P=0.011)were independent risk factors of OS in patients with T4N0M0 colon cancer.A nomogram model with good concordance and accuracy was constructed.CONCLUSION Enterostomy,T stage,right hemicolon,irregular review,and CA199 were independent risk factors for OS in patients with T4N0M0 colon cancer.The nomogram model exhibited good agreement and accuracy. 展开更多
关键词 T4n0m0 colon cancer PROGnOSIS multivariate analysis nOmOGRAm Colon cancer
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Comparative efficacy and safety between endoscopic submucosal dissection,surgery and definitive chemoradiotherapy in patients with cT1N0M0 esophageal cancer 被引量:1
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作者 Shu-Ai Luo Yu-Ying Sun +1 位作者 Ya-Ting Zeng Chun-Yu Huang 《World Journal of Gastrointestinal Endoscopy》 2024年第2期72-82,共11页
BACKGROUND Endoscopic submucosal dissection(ESD)and surgical resection are the standard of care for cT1N0M0 esophageal cancer(EC),whereas definitive chemoradiotherapy(d-CRT)is a treatment option.Nevertheless,the compa... BACKGROUND Endoscopic submucosal dissection(ESD)and surgical resection are the standard of care for cT1N0M0 esophageal cancer(EC),whereas definitive chemoradiotherapy(d-CRT)is a treatment option.Nevertheless,the comparative efficiency and safety of ESD,surgery and d-CRT for cT1N0M0 EC remain unclear.AIM To compare the efficiency and safety of ESD,surgery and d-CRT for cT1N0M0 EC.METHODS We retrospectively analyzed the hospitalized data of a total of 472 consecutive patients with cT1N0M0 EC treated at Sun Yat-sen University Cancer center between 2017-2019 and followed up until October 30th,2022.We analyzed demographic,medical recorded,histopathologic characteristics,imaging and endoscopic,and follow-up data.The Kaplan-Meier method and Cox proportional hazards modeling were used to analyze the difference of survival outcome by treatments.Inverse probability of treatment weighting(IPTW)was used to minimize potential confounding factors.RESULTS We retrospectively analyzed patients who underwent ESD(n=99)or surgery(n=220)or d-CRT(n=16)at the Sun Yat-sen University Cancer Center from 2017 to 2019.The median follow-up time for the ESD group,the surgery group,and the d-CRT group was 42.0 mo(95%CI:35.0-60.2),45.0 mo(95%CI:34.0-61.75)and 32.5 mo(95%CI:28.3-40.0),respectively.After adjusting for background factors using IPTW,the highest 3-year overall survival(OS)rate and 3-year recurrence-free survival(RFS)rate were observed in the ESD group(3-year OS:99.7% and 94.7% and 79.1%;and 3-year RFS:98.3%,87.4% and 79.1%,in the ESD,surgical,and d-CRT groups,respectively).There was no difference of severe complications occurring between the three groups(P≥0.05).Multivariate analysis showed that treatment method,histology and depth of infiltration were independently associated with OS and RFS.CONCLUSION For cT1N0M0 EC,ESD had better long-term survival and lower hospitalization costs than those who underwent d-CRT and surgery,with a similar rate of severe complications occurring. 展开更多
关键词 Retrospective study cT1n0m0 Esophageal squamous cell carcinoma Endoscopic submucosal dissection SURGERy Definitive chemoradiotherapy
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Learning Sequential and Structural Dependencies Between Nucleotides for RNA N6-Methyladenosine Site Identification
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作者 Guodong Li Bowei Zhao +4 位作者 Xiaorui Su Dongxu Li Yue Yang Zhi Zeng Lun Hu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第10期2123-2134,共12页
N6-methyladenosine(m6A)is an important RNA methylation modification involved in regulating diverse biological processes across multiple species.Hence,the identification of m6A modification sites provides valuable insi... N6-methyladenosine(m6A)is an important RNA methylation modification involved in regulating diverse biological processes across multiple species.Hence,the identification of m6A modification sites provides valuable insight into the biological mechanisms of complex diseases at the post-transcriptional level.Although a variety of identification algorithms have been proposed recently,most of them capture the features of m6A modification sites by focusing on the sequential dependencies of nucleotides at different positions in RNA sequences,while ignoring the structural dependencies of nucleotides in their threedimensional structures.To overcome this issue,we propose a cross-species end-to-end deep learning model,namely CR-NSSD,which conduct a cross-domain representation learning process integrating nucleotide structural and sequential dependencies for RNA m6A site identification.Specifically,CR-NSSD first obtains the pre-coded representations of RNA sequences by incorporating the position information into single-nucleotide states with chaos game representation theory.It then constructs a crossdomain reconstruction encoder to learn the sequential and structural dependencies between nucleotides.By minimizing the reconstruction and binary cross-entropy losses,CR-NSSD is trained to complete the task of m6A site identification.Extensive experiments have demonstrated the promising performance of CR-NSSD by comparing it with several state-of-the-art m6A identification algorithms.Moreover,the results of cross-species prediction indicate that the integration of sequential and structural dependencies allows CR-NSSD to capture general features of m6A modification sites among different species,thus improving the accuracy of cross-species identification. 展开更多
关键词 Cross-domain reconstruction cross-species prediction n6-methyladenosine(m6A)modification site RnA sequence sequential and structural dependencies
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Comparative Study of the Physicochemical Quality of the Waters of the Méné River (Sassandra Watershed, Ivory Coast) in the Dry Season and in the Rainy Season
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作者 Konan Lopez Kouamé Gansso Valentin Akilinon +2 位作者 Olivier Simon Mananga Kombo Gneneyougo Emile Soro Bi Tié Albert Goula 《Journal of Environmental Protection》 2024年第6期738-746,共9页
The study carried out on the waters of the Méné River led to an overall assessment of its water quality during the dry season and the rainy season. The analysis focused on eight (8) water samples taken from ... The study carried out on the waters of the Méné River led to an overall assessment of its water quality during the dry season and the rainy season. The analysis focused on eight (8) water samples taken from the river during a period of dry season (January-February) and a period of rainy season (June and September). The various physicochemical parameters were measured according to Afnor standardized methods. The readings of temperature, turbidity, pH and conductivity made it possible to account for the disturbances occurring in water quality. A temporal variation correlated with the seasons (dry or rainy) is noted. Turbidity depends on the concentration of suspended solids (SS) in the water and drained particles and therefore on the seasons. Just like the temperature, the conductivity changes with the season. The waters of the Méné River are generally acidic. The results obtained show that there is a low level of pollution by chlorides, phosphates, nitrites and nitrates. A slight pollution of the waters of Méné in organic matter (chemical oxygen demand values are less than 25 mg∙L−1 during dry season and 32.33 ± 4.73 mg∙L−1 during rainy season) was observed. The concentrations of metallic trace elements such as iron, manganese and aluminum indicate significant pollution of these waters by these elements. Overall, the waters of the Méné River are of satisfactory quality because all the physicochemical parameters analyzed have values below standards during the dry season as well as during the rainy season with the exception of COD and a few metallic trace elements. 展开更多
关键词 méné Physicochemical Parameters RIVER SEASOn Water Quality
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水平受荷桩“p-y+M-θ”分析方法
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作者 王立忠 赖踊卿 +1 位作者 洪义 张友虎 《岩土工程学报》 EI CAS CSCD 北大核心 2024年第5期905-918,共14页
中国近海海上风电机组开发建设中,大直径单桩基础形式使用占比超70%。现行p-y曲线设计方法主要适用于小直径柔性桩,对大直径单桩侧向及桩底受荷描述能力不足,导致其严重低估刚柔性桩和刚性桩(分别常用于中国和欧洲的近海风电工程)的变... 中国近海海上风电机组开发建设中,大直径单桩基础形式使用占比超70%。现行p-y曲线设计方法主要适用于小直径柔性桩,对大直径单桩侧向及桩底受荷描述能力不足,导致其严重低估刚柔性桩和刚性桩(分别常用于中国和欧洲的近海风电工程)的变形和承载能力,过于保守的设计给海上风电降本带来挑战。为此建立了能以统一的方式预测柔性、刚柔性和刚性单桩水平单调受荷响应的“p-y+M-θ”模型,并将该模型推广到循环荷载下单桩的响应分析。通过与相关试验结果比对发现,“p-y+M-θ”模型能较为准确地预测桩基水平加载响应。力图为水平受荷单桩工程设计提供简洁而可行的响应分析方法。 展开更多
关键词 软黏土 “p-y+m-θ”模型 水平受荷桩循环加载 试验结果对比
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Peterson图和图D_(m,n)的边PI指数
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作者 张丽 张辉 红霞 《宁夏师范学院学报》 2024年第4期5-15,共11页
利用分析法和分类讨论法,给出Peterson图和D_(m,n)图的边PI指数计算公式,丰富了图的PI指数理论.
关键词 边PI指数 Peterson 图Dm n
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指数有界双连续n阶m次积分C群的指数公式
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作者 贺凯丽 赵华新 刘娟娟 《西南民族大学学报(自然科学版)》 CAS 2024年第2期199-205,共7页
利用经典算子半群理论中的研究方法,基于指数有界双连续n阶m次积分C群和预解式的定义,给出指数有界双连续n阶m次积分C群与其预解式间积分的表示关系,得到指数有界双连续n阶m次积分C群的指数公式,从而推广了n阶m次积分C半群的相关结果,... 利用经典算子半群理论中的研究方法,基于指数有界双连续n阶m次积分C群和预解式的定义,给出指数有界双连续n阶m次积分C群与其预解式间积分的表示关系,得到指数有界双连续n阶m次积分C群的指数公式,从而推广了n阶m次积分C半群的相关结果,丰富了算子半群理论的研究内容. 展开更多
关键词 双连续nm次积分C群 指数公式 指数有界 预解式
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m6A甲基转移酶METTL3通过AFF4/NF-κB/MYC信号网络影响膀胱癌的研究进展 被引量:1
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作者 李濛濛 李金泽 +7 位作者 黄引 陈波 陈泽煜 柳良仁 艾建忠 杨璐 魏强 曹德宏 《现代泌尿外科杂志》 CAS 2023年第7期635-639,共5页
膀胱癌(BCa)是泌尿外科最常见的恶性肿瘤之一,发病机制目前尚未明确。甲基转移酶3(METTL3)是N6-甲基腺苷甲基转移酶复合物(m6A MTC)的核心部分,介导mRNA的甲基化修饰,影响mRNA的稳定性和翻译过程。研究表明METTL3可以通过AFF4/NF-κB/MY... 膀胱癌(BCa)是泌尿外科最常见的恶性肿瘤之一,发病机制目前尚未明确。甲基转移酶3(METTL3)是N6-甲基腺苷甲基转移酶复合物(m6A MTC)的核心部分,介导mRNA的甲基化修饰,影响mRNA的稳定性和翻译过程。研究表明METTL3可以通过AFF4/NF-κB/MYC信号网络对BCa细胞分裂增殖起到促进作用。该信号网络涉及多种信号分子,METTL3可分别影响AFF4、NF-κB和MYC的表达水平影响其下游通路,促进肿瘤发展。 展开更多
关键词 膀胱癌 n6-甲基腺苷(m6A) 甲基转移酶样蛋白3 AFF4 核因子kappa B myC
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(m,n)-内射和(m,n)-平坦函子
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作者 朱军 赵仁育 《兰州理工大学学报》 CAS 北大核心 2024年第2期142-147,共6页
设R是有单位元的结合环,m和n是两个固定的正整数.引入了(m,n)-内射函子和(m,n)-平坦函子的概念,研究了这两类函子的一些性质,利用(m,n)-内射函子和(m,n)-平坦函子给出了(m,n)-凝聚环和Von Neumann正则环的一些等价刻画.
关键词 (m n)-内射函子 (m n)-平坦函子 (m n)-凝聚环 Von neumann正则环 (预)覆盖 (预)包络
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m6A RNA甲基化调控因子在食管腺癌中的表达谱及其临床意义研究
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作者 马爽 唐锦浩 +1 位作者 王在瑞 赵晓慧 《岭南急诊医学杂志》 2024年第5期554-557,共4页
目的:探讨N6-甲基腺苷(m6A)RNA甲基化调控因子在食管腺癌中的表达模式及其预后价值,构建基于m6A调控因子的风险模型,用于预测患者生存并寻找新的治疗靶点。方法:从TCGA数据库获取81名食管腺癌患者和11名对照患者的RNA-seq数据及临床预... 目的:探讨N6-甲基腺苷(m6A)RNA甲基化调控因子在食管腺癌中的表达模式及其预后价值,构建基于m6A调控因子的风险模型,用于预测患者生存并寻找新的治疗靶点。方法:从TCGA数据库获取81名食管腺癌患者和11名对照患者的RNA-seq数据及临床预后信息。使用Limma包分析m6A RNA甲基化调控因子的表达与临床病理特征间的关系,采用Cox回归和LASSO算法构建包含五个m6A因子的风险模型。结果:17个m6A因子在食管腺癌组织中的表达显著高于正常组织。YTHDC2、EIF3A与T、N分期,IGF22BP1与远处转移相关。Cox分析和LASSO回归确定RBMX、HNRNPA2B1、WTAP、VIRMA四个预后因子并构建风险模型。Kaplan-Meier分析显示,高风险患者生存率显著低于低风险组。结论:m6A因子的表达与食管腺癌患者的临床特征密切相关,所构建的风险模型为预后预测和个性化治疗提供了新参考。 展开更多
关键词 食管腺癌 n6-甲基腺苷(m6A) 预后
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一类广义K(m,n)方程的行波解
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作者 赵传业 朱能 +2 位作者 张艳芬 阮小军 钟希杰 《南昌大学学报(理科版)》 CAS 2024年第3期214-220,230,共8页
运用微分方程定性理论和动力系统分支方法,研究了一类广义K(m,n)方程的行波解。考虑了两种情形:K(1,3,2)方程和K(2,3,3)方程。在不同的参数条件下,得到K(1,3,2)方程的紧孤子和K(2,3,3)方程的紧孤子及周期爆破波解。进一步通过数值模拟,... 运用微分方程定性理论和动力系统分支方法,研究了一类广义K(m,n)方程的行波解。考虑了两种情形:K(1,3,2)方程和K(2,3,3)方程。在不同的参数条件下,得到K(1,3,2)方程的紧孤子和K(2,3,3)方程的紧孤子及周期爆破波解。进一步通过数值模拟,分析其系统的分支相图和行波解的波形图。 展开更多
关键词 分支方法 K(m n)方程 紧孤子 周期爆破波解
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干扰RNA METTL14对大鼠肺成纤维细胞向肌成纤维细胞转化的影响
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作者 杨书宁 方丽 张其超 《临床肺科杂志》 2024年第12期1832-1838,共7页
目的探究干扰RNA甲基转移酶样蛋白14(methyltransferase-like 14,METTL14)在转化因子β1(transforming growth factorβ1,TGF-β1)诱导的大鼠肺成纤维细胞向肌成纤维细胞转移中的作用。方法大鼠肺成纤维细胞中构建METTL14小干扰RNA(smal... 目的探究干扰RNA甲基转移酶样蛋白14(methyltransferase-like 14,METTL14)在转化因子β1(transforming growth factorβ1,TGF-β1)诱导的大鼠肺成纤维细胞向肌成纤维细胞转移中的作用。方法大鼠肺成纤维细胞中构建METTL14小干扰RNA(small interfering RNA METTL14,si-METTL14)序列(si-METTL14-122、si-METTL14-300、si-METTL14-450)及对照siRNA(Negative control siRNA,si-NC)。建立TGF-β1(20 ng/mL)诱导肺成纤维细胞向肌成纤维细胞转化模型,转染si-NC及si-METTL14序列至肺成纤维细胞,检测METTL14、肌成纤维细胞标志物Ⅰ型胶原蛋白α1(collagen typeⅠalpha 1,COL1A1)、α-平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)及肌成纤维细胞转化负向调控因子Smad家族7号蛋白(Smad family member 7,Smad7)的mRNA和蛋白水平。结果si-METTL14有效沉默肺成纤维细胞METTL14表达水平。肌成纤维细胞转化模型组中METTL14表达显著升高(P<0.05)。与control组相比,TGF-β1诱导model组COLIA1、α-SMA表达显著升高,Smad7表达显著降低,转染si-METTL14抑制COLIA1、α-SMA表达,促进Smad7表达(P<0.05)。结论METTL14抑制TGF-β1诱导大鼠肺成纤维细胞向肌成纤维细胞转化,且可能与METTL14上调Smad7表达有关。 展开更多
关键词 n6-甲基腺苷(m6A)修饰 甲基转移酶样蛋白14 肺纤维化 成纤维细胞分化
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M1基因模式差异对H9N2亚型禽流感病毒增殖特性的影响
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作者 刘畅 丛郁霖 +3 位作者 朱艳婷 李思琦 孙艺学 丛彦龙 《中国家禽》 北大核心 2024年第11期18-24,共7页
为探究基质蛋白1(M1)对H9N2亚型禽流感病毒适应性的影响,研究基于M1的5种主要模式,利用反向遗传技术拯救了5株具有不同M1基因模式的H9N2亚型禽流感病毒,通过测定病毒的一步与多步生长曲线以及生长竞争优势试验探讨M1对H9N2亚型禽流感病... 为探究基质蛋白1(M1)对H9N2亚型禽流感病毒适应性的影响,研究基于M1的5种主要模式,利用反向遗传技术拯救了5株具有不同M1基因模式的H9N2亚型禽流感病毒,通过测定病毒的一步与多步生长曲线以及生长竞争优势试验探讨M1对H9N2亚型禽流感病毒增殖能力的影响,将MOI均为0.001的5株病毒共感染MDCK细胞,感染后48h提取细胞上清的病毒RNA,将反转录的cDNA样品进行单核苷酸多态性(SNP)测序。结果显示:M1为P5模式的H9N2亚型禽流感病毒增殖能力显著高于其余4株病毒(P<0.05),P5模式病毒的M1基因所涉及的9个可检测的氨基酸位点占比超过74%。研究表明,M1为P5模式的H9N2亚型禽流感病毒具有最强的增殖能力和明显的生长竞争优势,结果从M1对病毒增殖能力影响角度解释了该分支病毒在我国禽群中广泛流行的原因。 展开更多
关键词 禽流感 H9n2亚型 m1 模式差异 增殖能力
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Recent progress in N6-methyladenosine modification in ocular surface diseases 被引量:2
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作者 Wei Wang Jun Zou 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第4期645-651,共7页
N6-methyladenosine(m6A)modification is a reversible process promoted by“writers”,inhibited by“erasers”,and processed by“readers”.During the last decade,increasing emphasis has been placed on the underlying roles... N6-methyladenosine(m6A)modification is a reversible process promoted by“writers”,inhibited by“erasers”,and processed by“readers”.During the last decade,increasing emphasis has been placed on the underlying roles of m6A modification owing to their great importance in biological significance.The abnormal regulation of m6A modification will lead to aberrant cellular behavior and various diseases.Recently,studies have demonstrated that m6A modification is closely associated with the genesis and progression of ocular surface diseases(OSDs).This review focus on the role of m6A modification and research progress in OSDs including fungal keratitis,herpes simplex keratitis,immunerelated keratoconjunctival diseases,pterygium,ocular chemical burns,and Graves’ophthalmopathy,which may provide new insights into and prospective applications for OSDs. 展开更多
关键词 n6-methyladenosine m6A modification EPIGEnETICS ocular surface diseases
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cT1N0M0期食管癌内镜下非治愈性切除的研究进展
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作者 吴振坤(综述) 王贵齐(审校) 《中国肿瘤临床》 CAS CSCD 北大核心 2024年第5期253-257,共5页
随着消化内镜诊疗活动的广泛开展,内镜下切除已成为cT1N0M0期食管癌的标准治疗方案之一。然而,术后病理确认的非治愈性切除患者仍然面临复杂的后续管理选择。本文就cT1N0M0期食管癌内镜下非治愈性切除的国内外研究进展进行综述,指出现... 随着消化内镜诊疗活动的广泛开展,内镜下切除已成为cT1N0M0期食管癌的标准治疗方案之一。然而,术后病理确认的非治愈性切除患者仍然面临复杂的后续管理选择。本文就cT1N0M0期食管癌内镜下非治愈性切除的国内外研究进展进行综述,指出现有指南有关非治愈性切除的定义尚存争议,同时针对这部分患者,应在临床实践中制定选择性的个体化管理策略。 展开更多
关键词 内镜下切除 内镜黏膜下剥离术 非治愈性切除 cT1n0m0期 食管鳞癌
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H9N2亚型禽流感病毒M1和NA基因在昆虫细胞中的表达
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作者 王粲 张民秀 +6 位作者 谢芝勋 李孟 罗思思 李丹 阮志华 谢丽基 谢志勤 《中国动物检疫》 CAS 2024年第4期103-110,共8页
为通过昆虫细胞表达出H9N2亚型禽流感病毒M1和NA蛋白,并鉴定其免疫活性,利用PCR技术扩增H9N2亚型禽流感病毒M1和NA基因,以pFastBacDual为转移载体构建重组转移载体pFastBacDual-M1和pFastBacDual-NA;将阳性重组转移载体分别转化至DH10Ba... 为通过昆虫细胞表达出H9N2亚型禽流感病毒M1和NA蛋白,并鉴定其免疫活性,利用PCR技术扩增H9N2亚型禽流感病毒M1和NA基因,以pFastBacDual为转移载体构建重组转移载体pFastBacDual-M1和pFastBacDual-NA;将阳性重组转移载体分别转化至DH10Bac感受态细胞,得到重组杆粒rBacmid-M1和rBacmid-NA;将重组杆粒分别转染Sf9昆虫细胞,获得含M1和NA基因的重组杆状病毒rBV-M1和rBV-NA;运用IFA和Western-blot鉴定M1和NA蛋白的表达情况,同时以NA蛋白为包被抗原,运用间接ELISA方法鉴定NA蛋白的反应活性。结果显示,IFA鉴定均出现特异性绿色荧光,Western-blot检测M1和NA蛋白大小分别约为28和52 ku,ELISA检测NA蛋白对抗H9N2阳性血清有很高的反应值。结果表明,M1和NA蛋白可在昆虫细胞中特异性表达且具有反应原性。本试验为进一步研发H9N2亚型禽流感诊断技术和疫苗奠定了基础。 展开更多
关键词 禽流感病毒 H9n2亚型 m1蛋白 nA蛋白 Bac-to-Bac杆状病毒表达系统
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COVID-19 mutations:An overview
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作者 Malay Sarkar Irappa Madabhavi 《World Journal of Methodology》 2024年第3期7-22,共16页
The severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)belongs to the genus Beta coronavirus and the family of Coronaviridae.It is a positive-sense,non-segmented single-strand RNA virus.Four common types of hu... The severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)belongs to the genus Beta coronavirus and the family of Coronaviridae.It is a positive-sense,non-segmented single-strand RNA virus.Four common types of human coronaviruses circulate globally,particularly in the fall and winter seasons.They are responsible for 10%-30% of all mild upper respiratory tract infections in adults.These are 229E,NL63 of the Alfacoronaviridae family,OC43,and HKU1 of the Betacoronaviridae family.However,there are three highly pathogenic human coronaviruses:SARS-CoV-2,Middle East respiratory syndrome coronavirus,and the latest pandemic caused by the SARS-CoV-2 infection.All viruses,including SARS-CoV-2,have the inherent tendency to evolve.SARS-CoV-2 is still evolving in humans.Additionally,due to the development of herd immunity,prior infection,use of medication,vaccination,and antibodies,the viruses are facing immune pressure.During the replication process and due to immune pressure,the virus may undergo mutations.Several SARS-CoV-2 variants,including the variants of concern(VOCs),such as B.1.1.7(Alpha),B.1.351(Beta),B.1.617/B.1.617.2(Delta),P.1(Gamma),and B.1.1.529(Omicron)have been reported from various parts of the world.These VOCs contain several important mutations;some of them are on the spike proteins.These mutations may lead to enhanced infectivity,transmissibility,and decreased neutralization efficacy by monoclonal antibodies,convalescent sera,or vaccines.Mutations may also lead to a failure of detection by molecular diagnostic tests,leading to a delayed diagnosis,increased community spread,and delayed treatment.We searched PubMed,EMBASE,Covariant,the Stanford variant Database,and the CINAHL from December 2019 to February 2023 using the following search terms:VOC,SARS-CoV-2,Omicron,mutations in SARS-CoV-2,etc.This review discusses the various mutations and their impact on infectivity,transmissibility,and neutralization efficacy. 展开更多
关键词 Variant of concern SARS-CoV-2 Omicron n501y mutation E484K mutation
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E-三角范畴中的(n, m)-强ξ-Gorenstein投射对象
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作者 郭雯珺 《理论数学》 2024年第4期268-275,共8页
设C是一个E-三角范畴,ξ是C中的一个E-三角真类。在C中引入(n, m)-强ξ-Gorenstein投射对象的概念,研究了C中的对象与其合冲的这种ξ-Gorenstein投射性质之间的联系。作为应用,证明了ξ中对象X的ξ-Gorenstein投射维数小于等于m当且仅... 设C是一个E-三角范畴,ξ是C中的一个E-三角真类。在C中引入(n, m)-强ξ-Gorenstein投射对象的概念,研究了C中的对象与其合冲的这种ξ-Gorenstein投射性质之间的联系。作为应用,证明了ξ中对象X的ξ-Gorenstein投射维数小于等于m当且仅当存在C中的ξ-Gorenstein投射对象G,使得是(1, m)-强ξ-Gorenstein投射的。 展开更多
关键词 ξ-Gorenstein投射对象 ξ-Gorenstein投射维数 (n m)-强ξ-Gorenstein投射对象 合冲
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Upper gastrointestinal bleeding as an unusual manifestation of localized Ménétrier’s disease with an underlying lipoma:A case report
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作者 Michal Kmiecik Aleksandra Walczak +4 位作者 Pawel Samborski Jacek Paszkowski Agnieszka Dobrowolska Jacek Karczewski Ewelina Swora-Cwynar 《World Journal of Gastrointestinal Endoscopy》 2023年第1期10-18,共9页
BACKGROUND Ménétrier’s disease is a rare condition characterized by enlarged gastric folds,usually located in the whole body and fundus of the stomach.This report presents an unusual case of localized M... BACKGROUND Ménétrier’s disease is a rare condition characterized by enlarged gastric folds,usually located in the whole body and fundus of the stomach.This report presents an unusual case of localized Ménétrier’s disease elevated by a submucosal lipoma and thus looking like a polypoid mass and causing an episode of upper gastrointestinal bleeding.The mass was successfully removed with endoscopic submucosal dissection.CASE SUMMARY Esophagogastroduodenoscopy was performed on a 76-year-old male patient after an episode of upper gastrointestinal bleeding,manifesting as fatigue and melena.A large polypoid mass(4 cm×1 cm)with enlarged mucosal folds was found in the body of the stomach,between the lesser curvature and posterior wall.A small ulcer at the distal end of the mass was identified as the source of the bleeding.Biopsy was negative for neoplasia.Computed tomography showed a submucosal lesion beneath the affected mucosa,most likely a lipoma.The mass was removed en bloc with tunneling endoscopic submucosal dissection.Final pathology determined that the mass included Ménétrier’s disease and a submucosal lipoma.The patient was scheduled for follow-up esophagogastroduodenoscopy.CONCLUSION Localized Ménétrier’s disease can coexist with a submucosal lipoma creating a polypoid mass with risk of bleeding. 展开更多
关键词 ménétrier’s disease Submucosal lipoma Gastrointestinal hemorrhage Endoscopic submucosal dissection Submucosal tunneling endoscopic resection Case report
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A Comparative Study of YīJiàn Xiǎo Shìand A Small Incident Rendered by the Yangs
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作者 WANG Zai-jun ZHANG Jun-feng ZHANG Shun-sheng 《Journal of Literature and Art Studies》 2023年第11期825-830,共6页
Lu Xun’s short stories play a prominent role in the history of modern Chinese literature,and a number of Sinologists have studied them and published their English translations.This paper selects“YīJiàn Xiǎo S... Lu Xun’s short stories play a prominent role in the history of modern Chinese literature,and a number of Sinologists have studied them and published their English translations.This paper selects“YīJiàn Xiǎo Shì”in Lu Xun’s collection“Call to Arms”as the object of study,taking hypotaxis and parataxis as the starting point,and compares the translation of Yang Hsien-yi and Gladys Yang with the original version,studying the differences between the them in the process of C-E translation.It is hoped that some flexible conversion strategies in English-Chinese translation can be learned from the translation research. 展开更多
关键词 yīJiàn Xiǎo Shì A Small Incident rendered by yang Hsien-yi&Gladys yang hypotaxis and parataxis comparative study
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