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Surface reconstruction of complex contour lines based on chain code matching technique 被引量:1
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作者 姜晓彤 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期432-435,共4页
A new method for solving the tiling problem of surface reconstruction is proposed. The proposed method uses a snake algorithm to segment the original images, the contours are then transformed into strings by Freeman'... A new method for solving the tiling problem of surface reconstruction is proposed. The proposed method uses a snake algorithm to segment the original images, the contours are then transformed into strings by Freeman' s code. Symbolic string matching technique is applied to establish a correspondence between the two consecutive contours. The surface is composed of the pieces reconstructed from the correspondence points. Experimental results show that the proposed method exhibits a good behavior for the quality of surface reconstruction and its time complexity is proportional to mn where m and n are the numbers of vertices of the two consecutive slices, respectively. 展开更多
关键词 chain code string matching surface reconstruction local shape feature
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Multiple fault diagnosis of down-hole conditions of sucker-rod pumping wells based on Freeman chain code and DCA 被引量:13
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作者 LI Kun GAO Xian-wen +2 位作者 YANG Wei-bing DAI Ying-long TIAN Zhong-da 《Petroleum Science》 SCIE CAS CSCD 2013年第3期347-360,共14页
It is important to achieve continuous, stable and efficient pumping well operation in actual oilfield operation. Down-hole pumping well working conditions can be monitored in real-time and a reasonable production sche... It is important to achieve continuous, stable and efficient pumping well operation in actual oilfield operation. Down-hole pumping well working conditions can be monitored in real-time and a reasonable production scheme can be designed when computer diagnosis is used. However, it is difficult to make a comprehensive analysis to supply efficient technical guidance for operation of the pumping well with multiple faults of down-hole conditions, which cannot be effectively dealt with by the common methods. To solve this problem, a method based on designated component analysis (DCA) is used in this paper. Freeman chain code is used to represent the down-hole dynamometer card whose important characteristics are extracted to construct a designated mode set. A control chart is used as a basis for fault detection. The upper and lower control lines on the control chart are determined from standard samples in normal working conditions. In an incompletely orthogonal mode, the designated mode set could be divided into some subsets in which the modes are completely orthogonal. The observed data is projected into each designated mode to realize fault detection according to the upper and lower control lines. The examples show that the proposed method can effectively diagnose multiple faults of down-hole conditions. 展开更多
关键词 Sucker-rod pumping wells multiple faults designated component analysis control chart Freeman chain code dynamometer card
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Self-Dual Permutation Codes over Finite Chain Rings 被引量:1
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作者 YUAN Yuan ZHANG Huanguo 《Wuhan University Journal of Natural Sciences》 CAS 2007年第6期992-996,共5页
Permutation codes over finite chain rings are introduced; by using the character of the finite chain rings and the knowledge of representation of group, some conditions for existence or non-existence of self-dual perm... Permutation codes over finite chain rings are introduced; by using the character of the finite chain rings and the knowledge of representation of group, some conditions for existence or non-existence of self-dual permutation codes over finite chain rings are obtained. Specially, when the group is a direct product of a 2-group and a T-group, and the group action is transitive, the sufficient and necessary condition of the existence of permutation codes is given. 展开更多
关键词 finite chain ring group code permutation code self-dual code
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REVERSE DESIGN APPROACH FOR MECHANISM TRAJECTORY BASED ON CODE-CHAINS MATCHING 被引量:2
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作者 ZHANG Shuyou YI Guodong XU Xiaofeng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第3期86-90,共5页
Aiming at the problem of reverse-design of mechanism, a method based on the matching of trajectory code-chains is presented. The motion trajectory of mechanism is described with code-chain, which is normalized to simp... Aiming at the problem of reverse-design of mechanism, a method based on the matching of trajectory code-chains is presented. The motion trajectory of mechanism is described with code-chain, which is normalized to simplify the operation of geometric transformation. The geometric transforma-tion formulas of scale, mirror and rotation for trajectory code-chain are defined, and the reverse de-sign for mechanism trajectory is realized through the analysis and solution of similarity matching between the desired trajectory and the predefined trajectory. The algorithm program and prototype system of reverse design for mechanism trajectory are developed. Application samples show that the method can break the restriction of trajectory patterns in matching, meet the demand of partial match-ing, and overcome the influence of geometric transformation of trajectory on the reverse design for mechanism. 展开更多
关键词 TRAJECTORY code-chain Similarity matching Reverse-design
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Face Recognition Using Chain Codes
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作者 Nazmeen B. Boodoo-Jahangeer Sunilduth Baichoo 《Journal of Signal and Information Processing》 2013年第3期154-157,共4页
Face recognition is an active area of biometrics. This study investigates the use of Chain Codes as features for recognition purpose. Firstly a segmentation method, based on skin color model was applied, followed by c... Face recognition is an active area of biometrics. This study investigates the use of Chain Codes as features for recognition purpose. Firstly a segmentation method, based on skin color model was applied, followed by contour detection, then the chain codes of the contours were determined. The first difference of chain codes were calculated since the latter is invariant to rotation. The features were calculated and stored in a matrix. Experiments were performed using the University of Essex Face database, and results show a recognition rate of 95% with this method, when compared with Principal Components Analysis (PCA) giving 87.5% recognition rate. 展开更多
关键词 FACE RECOGNITION BIOMETRICS chain codeS PCA
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Auto-selection order of Markov chain for background sequences with chi-square test
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作者 谢雪英 孙啸 陆祖宏 《Journal of Southeast University(English Edition)》 EI CAS 2003年第4期311-316,共6页
Modeling non coding background sequences appropriately is important for the detection of regulatory elements from DNA sequences. Based on the chi square statistic test, some explanations about why to choose higher ... Modeling non coding background sequences appropriately is important for the detection of regulatory elements from DNA sequences. Based on the chi square statistic test, some explanations about why to choose higher order Markov chain model and how to automatically select the proper order are given in this paper. The chi square test is first run on synthetic data sets to show that it can efficiently find the proper order of Markov chain. Using chi square test, distinct higher order context dependences inherent in ten sets of sequences of yeast S.cerevisiae from other literature have been found. So the Markov chain with higher order would be more suitable for modeling the non coding background sequences than an independent model. 展开更多
关键词 non coding sequences regulatory elements chi square test Markov chain
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非编码RNA在肺纤维化过程中的调控作用
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作者 于经邦 吴亚云 《中国组织工程研究》 CAS 北大核心 2025年第8期1659-1666,共8页
背景:截至目前,肺纤维化的发病机制不明,治疗手段或者药物有限。大量研究发现,非编码RNA在肺纤维化的发生发展过程中发挥重要作用。目的:综述近年来非编码RNA在肺纤维化发病机制中的调控作用,深入了解肺纤维化的发病机制。方法:由第一... 背景:截至目前,肺纤维化的发病机制不明,治疗手段或者药物有限。大量研究发现,非编码RNA在肺纤维化的发生发展过程中发挥重要作用。目的:综述近年来非编码RNA在肺纤维化发病机制中的调控作用,深入了解肺纤维化的发病机制。方法:由第一作者应用计算机检索2000-2024年出版的文献,以“非编码RNA,微小RNA,长链非编码RNA,环状RNA,肺纤维化,综述”等为中文检索词检索中国知网、万方和维普数据库;以“ncRNA,miRNA,lncRNA,circRNA,Pulmonary fibrosis,review”等为英文检索词检索PubMed数据库,按照入选标准最终共纳入65篇文献进行综述。结果与结论:肺纤维化作为一种慢性且通常致命的肺部疾病,不仅可能自发产生,也可能是其他疾病的继发结果,主要特点是肺部间质中细胞外基质的异常增生和大量积累。非编码RNA是指由基因组转录出来的RNA分子,这些RNA分子并不涉及蛋白质的编码过程,凭借其调节能力已成为各种生物学现象中的一线分子参与者之一。非编码RNA在肺纤维化的发病机制中扮演着关键角色,微小RNA(miRNA)、长链非编码RNA(lncRNA)和环状RNA(circRNA)可以通过影响基因表达、转录后修饰以及细胞间的信号传导,参与到肺纤维化的发展过程中,为后续探索肺纤维化疾病的具体分子发生机制提供了新方向,为研发肺纤维化疾病的新靶向药物提供了理论依据及新思路。 展开更多
关键词 非编码RNA 微小RNA 长链非编码RNA 环状RNA 肺纤维化 综述
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CYCLIC AND NEGACYCLIC CODES OF LENGTH 2p^s OVER F_(p^m) + uF_(p^m) 被引量:2
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作者 刘修生 许小芳 《Acta Mathematica Scientia》 SCIE CSCD 2014年第3期829-839,共11页
In this article, we focus on cyclic and negacyclic codes of length 2p^s over the ring R = Fp^m + uFp^m, where p is an odd prime. On the basis of the works of Dinh (in J.Algebra 324,940-950,2010), we use the Chinese... In this article, we focus on cyclic and negacyclic codes of length 2p^s over the ring R = Fp^m + uFp^m, where p is an odd prime. On the basis of the works of Dinh (in J.Algebra 324,940-950,2010), we use the Chinese Remainder Theorem to establish the algebraic structure of cyclic and negacyclic codes of length 2p^s over the ring Fp^m + uFp^m in terms of polynomial generators. Furthermore, we obtain the number of codewords in each of those cyclic and negacyclic codes. 展开更多
关键词 Negacyclic codes cyclic codes repeated-root codes finite chain ring finite local ring
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CYCLIC CODES OVER FORMAL POWER SERIES RINGS 被引量:1
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作者 Dougherty Steven T. 刘宏伟 《Acta Mathematica Scientia》 SCIE CSCD 2011年第1期331-343,共13页
In this article, cyclic codes and negacyclic codes over formal power series rings are studied. The structure of cyclic codes over this class of rings is given, and the relationship between these codes and cyclic codes... In this article, cyclic codes and negacyclic codes over formal power series rings are studied. The structure of cyclic codes over this class of rings is given, and the relationship between these codes and cyclic codes over finite chain rings is obtained. Using an isomorphism between cyclic and negacyclic codes over formal power series rings, the structure of negacyclic codes over the formal power series rings is obtained. 展开更多
关键词 Finite chain rings cyclic codes negacyclic codes γ-adic codes
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Adding Sub-chain Method for Structural Synthesis of Planar Closed Kinematic Chains 被引量:2
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作者 DENG Zongquan YANG Fei TAO Jianguo 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第2期206-213,共8页
For at least the past five decades,structural synthesis has been used as a main means of finding better mechanisms with some predefined function.In structural synthesis,isomorphism identification is still a problem un... For at least the past five decades,structural synthesis has been used as a main means of finding better mechanisms with some predefined function.In structural synthesis,isomorphism identification is still a problem unsolved well,and to solve this problem is very significant to the design of new mechanisms.According to the given degree of freedom(DOF) and link connection property of planar closed chain mechanisms,vertex assortment is obtained.For solving the isomorphism problem,a method of the adding sub-chains is proposed with the detailed steps and algorithms in the synthesizing process.Employing this method,the identification code and formation code of every topological structure are achieved,therefore many isomorphic structures could be eliminated in time during structural synthesis by comparing those codes among different topological graphs,resulting in the improvement of synthesizing efficiency and accuracy,and the approach for eliminating rigid sub-chains in and after the synthesizing process is also presented.Some examples are given,including how to add sub-chains,how to detect simple rigid sub-chains and how to obtain identification codes and formulation codes et al.Using the adding sub-chain method,the relative information of some common topological graphs is given in the form of table.The comparison result is coincident with many literatures,so the correctness of the adding sub-chain method is convinced.This method will greatly improve the synthesizing efficiency and accuracy,and has a good potential for application. 展开更多
关键词 structural synthesis adding sub-chain method identification code formation code rigid sub-chains
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ON THE CHARACTERIZATION OF CYCLIC CODES OVER TWO CLASSES OF RINGS
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作者 刘修生 《Acta Mathematica Scientia》 SCIE CSCD 2013年第2期413-422,共10页
Let R be a finite chain ring with maximal ideal (7) and residue field F,and letγ be of nilpotency index t. To every code C of length n over R, a tower of codes C = (C : γ0) C_ (C: 7) C ... C_ (C: γ2) C_ ... Let R be a finite chain ring with maximal ideal (7) and residue field F,and letγ be of nilpotency index t. To every code C of length n over R, a tower of codes C = (C : γ0) C_ (C: 7) C ... C_ (C: γ2) C_ .-. C_ (C:γ^t-1) can be associated with C, where for any r C R, (C : r) = {e C Rn I re E C}. Using generator elements of the projection of such a tower of codes to the residue field F, we characterize cyclic codes over R. This characterization turns the condition for codes over R to be cyclic into one for codes over the residue field F. Furthermore, we obtain a characterization of cyclic codes over the formal power series ring of a finite chain ring. 展开更多
关键词 Finite chain rings formal power series rings cyclic codes tower of codes Hensel lift
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Recognition of Partially Occluded Objects Based on Segmentation by Median Filtering of Extended Direction Code
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作者 Wang Yanping Larmagnac Jean-Pierre +1 位作者 Yuan Jie Zhao Hengzhuo 《Wuhan University Journal of Natural Sciences》 CAS 1997年第4期53-56,共4页
The image contour is segmented into lines, arcs and smooth curves by median filtering of extended direction code. Based on this segmentation, a set of new local invariant features are proposed to recognize partially o... The image contour is segmented into lines, arcs and smooth curves by median filtering of extended direction code. Based on this segmentation, a set of new local invariant features are proposed to recognize partially occluded objects, which is more reasonable compared with conventional corner features. The matching results of some typical examples shows that these features are robust ,effective in recognition. 展开更多
关键词 pattern recognition freeman's code extended code median filtering CORNER
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Network Coding for Wireless Sensor Network Cluster over Rayleigh Fading Channel: Finite State Markov Chain
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作者 Mohammad Alhihi 《International Journal of Communications, Network and System Sciences》 2017年第1期1-11,共11页
Network Coding (NC) is confirmed to be power and bandwidth efficient technique, because of the less number of transmitted packets over the network. Wireless Sensor Network (WSN) is usually power limited network applic... Network Coding (NC) is confirmed to be power and bandwidth efficient technique, because of the less number of transmitted packets over the network. Wireless Sensor Network (WSN) is usually power limited network application, and in many scenarios it is power and bandwidth limited application. The proposed scenario in this paper applies the advantages of NC over WSN to obtain such power and bandwidth efficient WSN. To take the advantages of NC over the one of the most needed applications i.e., WSN, we come up to what this paper is discussing. We consider a WSN (or its cluster) that consists of M nodes that transmit equal-length information packets to a common destination node D over wireless Rayleigh block-fading channel where the instantaneous SNR is assumed to be constant over a single packet transmission period. Finite-State packet level Markov chain (FSMC) model is applied to give the channel more practical aspect. The simulation results showed that applying NC over the WSN cluster improved the channel bandwidth significantly by decreasing the number of the Automatic Repeat Request (ARQ), resulting in improving the power consumption significantly. The results are collected for different transmission distances to evaluate the behavior to the proposed scenario with regard to the bath losses effect. 展开更多
关键词 RAYLEIGH FADING Channel Network Coding Finite-Stage MARKOV chain
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Research progress of long-chain non coding RNA malat1 in cervical cancer
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作者 Wen Zhou Yue Xia +2 位作者 Bi-Bo Tan Chang-Xian Chen Ling-Zhao Mo 《Journal of Hainan Medical University》 2019年第24期72-75,共4页
Objective:Long non coding RNA (lncrna) is a kind of RNA with a length of more than 200 bp but not directly encoding protein. It is found that lncrna involves many important biological processes, such as cell prolifera... Objective:Long non coding RNA (lncrna) is a kind of RNA with a length of more than 200 bp but not directly encoding protein. It is found that lncrna involves many important biological processes, such as cell proliferation, cell survival, cell differentiation, organogenesis, genomic imprinting, and chromatin remodeling. The metastasis associated lung cancer transcript 1 (malat1) is an important member of the lncrna family. It is located on human chromosome 11 (11p13.1), with a length of 8000 BP. It is an intergenic transcript. Malat1 is highly expressed in cervical cancer, which may be closely related to the occurrence and development of cervical cancer, and may become a new target for diagnosis and treatment of cervical cancer. This article reviews the research status of the relationship between lncrna malat1 and cervical cancer. 展开更多
关键词 long chain non CODING RNA malat1 CERVICAL cancer
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Construction of Self-dual Codes over F_p+vF_p
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作者 ZHANG Guang-hui WANG Dong-qing 《Chinese Quarterly Journal of Mathematics》 2018年第4期358-368,共11页
In this paper, we give an explicit construction for self-dual codes over F_p+vF_p(v^2= v) and determine all the self-dual codes over F_p+ vF_p by using self-dual codes over finite field F_p, where p is a prime.
关键词 Linear code SELF-DUAL code codes OVER Fp +vFp non-chain ring
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缺血性脑卒中患者血清差异基因的筛选及生物信息学研究及验证
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作者 王洋 汪露 李辉 《新疆医科大学学报》 CAS 2024年第6期817-823,共7页
目的研究缺血性脑卒中患者血清差异基因的筛选及生物信息学。方法以2023年3月-2024年3月在新疆医科大学第二附属医院神经内科确诊的80例缺血性脑卒中患者为病例组,选择同期80例健康体检者为对照组。分别挑选两组各10例受试者的外周血清... 目的研究缺血性脑卒中患者血清差异基因的筛选及生物信息学。方法以2023年3月-2024年3月在新疆医科大学第二附属医院神经内科确诊的80例缺血性脑卒中患者为病例组,选择同期80例健康体检者为对照组。分别挑选两组各10例受试者的外周血清采用芯片差异性基因鉴定法筛选缺血性脑卒中差异表达的长链非编码RNA(lncRNA),并采用KEGG通路富集和基因本体论(GO)分析鉴定差异表达基因发挥的生物学功能。挑选2个上调和2个下调的lncR-NAs,在两组患者外周血中采用实时荧光定量PCR(qRT-PCR)法检测表达量,采用受试者工作特征曲线(Receiver operating characteristic,ROC)计算差异性表达lncRNAs诊断缺血性脑卒中的曲线下面积(Area under the curve,AUC)。结果共检测到34个高表达和16个低表达的lncR-NAs。KEGG通道分析显示,差异表达的lncRNAs涉及肿瘤坏死因子(TNF)信号通路、类风湿性关节炎、细胞因子与细胞因子受体相互作用,病毒蛋白与细胞因子和细胞因子受体的相互作用、癌症的转录失调、沙门氏菌感染、白细胞介素(IL)-17信号通路、趋化因子信号通路。GO分析显示,差异表达的lncRNAs涉及白细胞黏附调控、细胞黏附调节、白细胞与其他细胞黏附、细胞趋化性、T细胞活化、骨髓细胞分化、止血和凝血。qRT-PCR检测显示,与对照组比较,病例组患者A1BG-AS1和BRWD1-AS2表达量升高,BVES-AS1和C10ORF71-AS1表达量降低,差异有统计学意义(P<0.05)。ROC分析显示,A1BG-AS1、BRWD1-AS2、BVES-AS1和C10ORF71-AS1表达量诊断缺血性脑卒中的AUC分别为0.803、0.856、0.897和0.798(P<0.001)。结论缺血性脑卒中患者外周血中A1BG-AS1、BRWD1-AS2、BVES-AS1和C10ORF71-AS1基因差异性表达,可以辅助缺血性脑卒中的疾病诊断。 展开更多
关键词 缺血性脑卒中 微阵列芯片 高通量测序 长链非编码RNA
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血清FGL1、LncSChLAP1对晚期非小细胞肺癌免疫治疗效果及预后评估的价值
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作者 夏宁 周泽军 +2 位作者 方申存 王尊乔 潘宴青 《疑难病杂志》 CAS 2024年第3期346-351,共6页
目的分析血清纤维蛋白样因子1(FGL1)、长链非编码RNA SChLAP1(LncSChLAP1)评估接受免疫治疗的晚期非小细胞肺癌(NSCLC)患者疗效及预后的价值。方法选取2019年4月—2022年12月南京市胸科医院呼吸内科诊治晚期NSCLC患者98例为NSCLC组,均... 目的分析血清纤维蛋白样因子1(FGL1)、长链非编码RNA SChLAP1(LncSChLAP1)评估接受免疫治疗的晚期非小细胞肺癌(NSCLC)患者疗效及预后的价值。方法选取2019年4月—2022年12月南京市胸科医院呼吸内科诊治晚期NSCLC患者98例为NSCLC组,均接受免疫检查点抑制剂治疗,根据疗效分为有效亚组74例和无效亚组24例,以同期医院健康体检者50例为健康对照组。酶联免疫吸附实验检测NSCLC患者血清FGL1水平,实时荧光定量PCR检测血清LncSChLAP1水平;多因素Logistic回归分析影响晚期NSCLC患者化疗疗效的因素;受试者工作特征曲线分析血清FGL1、LncSChLAP1对晚期NSCLC患者免疫治疗疗效的预测价值;Kaplan-Meier曲线分析血清FGL1、LncSChLAP1对晚期NSCLC患者生存预后的影响。结果血清FGL1、LncSChLAP1水平比较,NSCLC组高于健康对照组(t/P=57.365/<0.001、28.443/<0.001)。无效亚组TNM分期Ⅳ期比例、血清FGL1、LncSChLAP1水平高于有效亚组(χ^(2)/P=15.375/<0.001,t/P=35.077/<0.001、35.127/<0.001)。血清FGL1、LncSChLAP1高是影响晚期NSCLC患者免疫治疗疗效的独立危险因素[OR(95%CI)=1.327(1.104~1.596)、1.415(1.094~1.829)];血清FGL1、LncSChLAP1及两项联合的AUC分别为0.856、0.792、0.905,两者联合优于各自单独预测效能(Z/P=4.258/0.007、5.119/<0.001)。FGL1高、低表达组1年总体生存率分别为22.92%(11/48)、60.00%(30/50),LncSChLAP1高、低表达组1年总体生存率分别为27.66%(13/47)、54.90%(28/51),FGL1高表达组、LncSChLAP1高表达组晚期NSCLC患者1年累积生存率分别低于FGL1低表达组、LncSChLAP1低表达组(χ^(2)/P=14.180/<0.001、17.553/<0.001)。结论晚期NSCLC患者血清FGL1、LncSChLAP1升高,是新的评估晚期NSCLC患者免疫治疗疗效及生存预后的血清标志物。 展开更多
关键词 非小细胞肺癌 纤维蛋白样因子1 长链非编码RNA SChLAP1 免疫治疗 疗效 预后
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长链非编码RNA GC1靶向微小RNA-551b-3p抑制食管癌的作用及分子机制研究
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作者 冯潇 张江浩 +1 位作者 王博 惠双 《临床内科杂志》 CAS 2024年第5期346-351,共6页
目的探讨长链非编码RNA(LncRNA)鸟苷酸环化酶1(GC1)对食管癌的影响,并探讨其靶向微小RNA-551b-3p(miR-551b-3p)的分子机制。方法建立食管癌荷瘤裸小鼠模型,随机分为GC1、miR-551b-3p上、下调组及其对应对照组与模型组共9组,每组8只。末... 目的探讨长链非编码RNA(LncRNA)鸟苷酸环化酶1(GC1)对食管癌的影响,并探讨其靶向微小RNA-551b-3p(miR-551b-3p)的分子机制。方法建立食管癌荷瘤裸小鼠模型,随机分为GC1、miR-551b-3p上、下调组及其对应对照组与模型组共9组,每组8只。末次给药次日处死裸小鼠,称取瘤体质量,计算抑瘤率;取肿瘤组织检测LncRNA GC1、miR-551b-3p基因表达水平和细胞周期因子(CyclinD1)、p21、B淋巴细胞瘤-2(Bcl-2)、Bcl-2相关x(Bax)基因与蛋白表达水平;观察肿瘤组织病理改变;采用流式细胞术检测肿瘤细胞凋亡率;采用双荧光素酶报告基因实验验证LncRNA GC1与miR-551b-3p的调控关系。另取人食管癌细胞株Eca109分为9组,每组3个复孔,其中基因干扰组命名同上,另设置空白组,培养48h后观察细胞LncRNA GC1、miR-551b-3p基因表达水平、形态学改变、凋亡率、CyclinD1、p21、Bcl-2、Bax基因与蛋白表达水平。结果动物实验:与模型组和相应对照组比较,GC1上调组与miR-551b-3p下调组瘤体质量、CyclinD1和Bcl-2基因与蛋白表达水平均上升,抑瘤率、细胞凋亡率、miR-551b-3p基因、p21和Bax基因与蛋白表达水平均下降;GC1下调组与miR-551b-3p上调组瘤体质量、CyclinD1和Bcl-2基因与蛋白表达水平均下降,抑瘤率和细胞凋亡率、miR-551b-3p基因、p21和Bax基因与蛋白表达水平均上升;GC1上调组LncRNA GC1基因表达水平上升,GC1下调组LncRNA GC1基因表达水平下降(P<0.05)。与转染野生型GC1的腺病毒载体相比,转染突变型GC1的腺病毒载体的miR-551b-3p荧光素酶相对活性上升(P<0.05)。细胞实验:LncRNA GC1和miR-551b-3p基因表达水平、细胞形态学改变与凋亡率、CyclinD1、p21、Bcl-2、Bax基因与蛋白表达水平变化趋势均与动物实验相同。结论下调LncRNA GC1、上调miR-551b-3p表达水平均可抑制食管癌进展,且下调LncRNA GC1可靶向上调miR-551b-3p,并降低CyclinD1和Bcl-2活性、上升p21和Bax活性。 展开更多
关键词 食管癌 长链非编码RNA 鸟苷酸环化酶1 微小RNA 抑瘤率 凋亡
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稀疏网络编码中秩分布分析模型研究
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作者 王练 王贺 +1 位作者 李永恒 李仙 《重庆邮电大学学报(自然科学版)》 CSCD 北大核心 2024年第3期458-468,共11页
针对现有稀疏网络编码研究中线性相关概率性能指标精准度较低的问题,提出基于马尔可夫链的性能分析模型。对线性相关概率、秩的概率分布等性能指标及其复杂度进行分析,并通过该性能分析模型分析编码包传输后期的译码成功概率;基于吸收... 针对现有稀疏网络编码研究中线性相关概率性能指标精准度较低的问题,提出基于马尔可夫链的性能分析模型。对线性相关概率、秩的概率分布等性能指标及其复杂度进行分析,并通过该性能分析模型分析编码包传输后期的译码成功概率;基于吸收马尔可夫链计算编码包传输过程中的瞬态、吸收态以及各状态间的状态转移概率,并对状态转移概率中蒙特卡罗模拟误差较大的问题进行改进,由状态转移概率构建吸收马尔可夫链基本矩阵,得出信宿端收到非再生包的线性相关概率,进而推导出秩的概率分布和译码成功概率性能指标。仿真结果表明,在相同条件下所提模型性能指标精确度均优于对比模型,且能精确地评估信宿端解码矩阵秩的概率分布、译码成功概率等稀疏网络编码的译码行为。 展开更多
关键词 网络编码 稀疏网络编码 吸收马尔可夫链模型 线性相关概率 秩的概率分布
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lncRNA H19和IGF2基因在乳腺癌组织中的表达水平及印记状态
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作者 魏雪 文雪 +3 位作者 谢潇 王月媛 黄丹 杨明 《吉林大学学报(医学版)》 CAS CSCD 北大核心 2024年第4期1109-1115,共7页
目的:研究长链非编码RNA(lncRNA)H19和胰岛素样生长因子2(IGF2)基因在乳腺癌组织中的表达水平,分析其印记状态。方法:采用实时荧光定量PCR(RT-qPCR)法检测乳腺癌组织及癌旁组织中H19和IGF2 mRNA表达水平,分析H19和IGF2 mRNA在乳腺癌组... 目的:研究长链非编码RNA(lncRNA)H19和胰岛素样生长因子2(IGF2)基因在乳腺癌组织中的表达水平,分析其印记状态。方法:采用实时荧光定量PCR(RT-qPCR)法检测乳腺癌组织及癌旁组织中H19和IGF2 mRNA表达水平,分析H19和IGF2 mRNA在乳腺癌组织及癌旁组织中的表达差异,利用单核苷酸多态性(SNP)区分等位基因表达情况(纯合或杂合),基因组DNA中IGF2(ApaⅠ位点)或H19(AluⅠ位点)为杂合则进行印记分析,确定H19和IGF2在乳腺癌组织中的印记状态,即印记保持(MOI)或印记丢失(LOI)。分析乳腺癌组织中H19和IGF2表达与分子分型的关系。结果:RT-qPCR法检测,乳腺癌组织中H19和IGF2 mRNA表达水平高于癌旁组织(P<0.01),H19 mRNA表达水平与IGF2 mRNA表达水平呈正相关关系(r=0.567,P<0.01)。不同分子分型乳腺癌患者癌组织中H19 mRNA表达水平均高于癌旁组织(P<0.05或P<0.01)。H19和IGF2在乳腺癌组织中均存在LOI,IGF2的LOI发生率为36.7%,高于H19的LOI发生率(4.3%)。RT-qPCR法检测,IGF2 LOI组乳腺癌组织中IGF2 mRNA表达水平明显高于IGF2 MOI组(P<0.01)。结论:乳腺癌组织中H19和IGF2 mRNA表达水平明显高于癌旁组织,IGF2的LOI发生率高于H19的LOI发生率,IGF2的LOI可能是乳腺癌发病的关键因素之一。 展开更多
关键词 乳腺肿瘤 长链非编码RNA H19 胰岛素样生长因子2 印记丢失 单核苷酸多态性
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