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Gene Expression Data Analysis Based on Mixed Effects Model
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作者 Yuanbo Dai 《Journal of Computer and Communications》 2025年第2期223-235,共13页
DNA microarray technology is an extremely effective technique for studying gene expression patterns in cells, and the main challenge currently faced by this technology is how to analyze the large amount of gene expres... DNA microarray technology is an extremely effective technique for studying gene expression patterns in cells, and the main challenge currently faced by this technology is how to analyze the large amount of gene expression data generated. To address this, this paper employs a mixed-effects model to analyze gene expression data. In terms of data selection, 1176 genes from the white mouse gene expression dataset under two experimental conditions were chosen, setting up two conditions: pneumococcal infection and no infection, and constructing a mixed-effects model. After preprocessing the gene chip information, the data were imported into the model, preliminary results were calculated, and permutation tests were performed to biologically validate the preliminary results using GSEA. The final dataset consists of 20 groups of gene expression data from pneumococcal infection, which categorizes functionally related genes based on the similarity of their expression profiles, facilitating the study of genes with unknown functions. 展开更多
关键词 Mixed Effects model Gene expression Data Analysis Gene Analysis Gene Chip
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Expression model for multiple relationships in the ontology of traditional Chinese medicine knowledge 被引量:1
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作者 Mingyue Gao Lepeng Wang Meng Cui 《Journal of Traditional Chinese Medical Sciences》 2016年第1期59-65,共7页
Objective:To explore multiple relationships in traditional Chinese medicine(TCM)knowledge by comparing binary and multiple relationships during knowledge organization.Methods:Characteristics of binary and multiple sem... Objective:To explore multiple relationships in traditional Chinese medicine(TCM)knowledge by comparing binary and multiple relationships during knowledge organization.Methods:Characteristics of binary and multiple semantic relationships as well as their associations are described.A method to classify multiple relationships based on the involvement of time is proposed and theoretically validated using examples from the ancient TCM classic Important Formulas Worth a Thousand Gold Pieces.The classification includes parallel multiple relationships,restricted multiple relationships,multiple relationships that involve time,and multiple relationships that involve time restriction.Next,construction of multiple semantic relationships for TCM concepts in each classification using Protege,an ontology editing tool is described.Results:Protege is superior to a binary relationship and less than ideal with multiple relationships during the constitution of concept relationships.Conclusion:When applied in TCM,the semantic relationships constructed by Protege are superior than those constructed by correlation and/or attribute relationships,but less ideal than those constructed by the human cognitive process. 展开更多
关键词 Multiple relationships ONTOLOGY expression model In traditional Chinese medicine knowledge
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Expression,purification and molecular modeling of iron-containing superoxide dismutase from Acidithiobacillus ferrooxidans 被引量:1
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作者 刘元东 高建 +5 位作者 邱冠周 刘学端 张成桂 欧阳叙东 蒋莹 曾佳 《中国有色金属学会会刊:英文版》 EI CSCD 2008年第6期1361-1366,共6页
从 Acidithiobacillus ferrooxidans 的 superoxide dismutase (草皮) 可以在它的忍耐起一个重要作用到 bioleaching 的极其有毒、氧化的环境。这基因在 Escherichia 被克隆然后成功地表示了 coli。表示蛋白质被一步舞亲密关系层析最后... 从 Acidithiobacillus ferrooxidans 的 superoxide dismutase (草皮) 可以在它的忍耐起一个重要作用到 bioleaching 的极其有毒、氧化的环境。这基因在 Escherichia 被克隆然后成功地表示了 coli。表示蛋白质被一步舞亲密关系层析最后净化到同质并且观察了根据 SDS 页和 MALDI-TOF-MS 更暗淡。金属内容决心和 recombinant 蛋白质的光系列结果证实蛋白质是包含铁的 superoxide dismutase。为蛋白质的分子的建模表明铁原子被 His26, His75, Asp158 和 His162 绑扎。 展开更多
关键词 超氧歧化酶 基因表达 纯化 分子模型
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Expression Pattern of Testis-specific Expressed Gene 2 in Cryptorchidism Model and Its Role in Apoptosis of Spermatogenic Cells 被引量:2
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作者 胡涛 王智宇 +4 位作者 曾甫清 陈晓春 顾朝辉 郑丽端 童强松 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2010年第2期193-197,共5页
In our previous study, we identified a novel testis-specific expressed gene 2 (TSEG-2) from mouse testis. To further investigate its functions, 35 male Balb/c mice (8 weeks old) were divided into cryptorchidism gr... In our previous study, we identified a novel testis-specific expressed gene 2 (TSEG-2) from mouse testis. To further investigate its functions, 35 male Balb/c mice (8 weeks old) were divided into cryptorchidism group (n=20), sham group (n=10), and control group (n=5). In cryptorchidism group, the right testes were anchored to the inner lateral abdominal wall. In situ hybridization (ISH) was applied to measure the localization of TSEG-2 in mouse testis. Real-time quantitative PCR was performed to detect the expression of TSEG-2 gene. Meanwhile, under the mediation of polyethylenimine (PEI), the recombinant vector pEGFP-TSEG-2 (n=5) or empty vector (mock, n=5) was transfected into the testis of male mice. The transfection efficiencies were measured under a fluorescence microscope. The apoptosis of spermatogenic cells was detected by terminal deoxynuleotidyl-mediated nick end labeling (TUNEL). The results showed that TSEG-2 was expressed in convoluted seminiferous tubules, more precisely, in spermatogonia and spermatocytes. As compared with sham and control groups, the TSEG-2 transcription was significantly enhanced (P〈0.05) and was correlated with apoptosis of spermatogenic cells in cryptorchid testes (P〈0.05). PEI was efficient in mediating transfeetion of TSEG-2 into seminiferous tubules of testis. One week post-transfection, intratesticular injection of TSEG-2 resulted in increased apoptosis of spermatogenic cells in vivo (P〈0.05). These results indicate that TSEG-2 may participate in the apoptosis of spermatogenic cells and the pathogenesis of cryptorchidism. 展开更多
关键词 animal model testis-specific expressed gene 2 polyethylenimine APOPTOSIS
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Expression of calbindin D28K in substantia nigra of model rats with Parkinson disease 被引量:2
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作者 Dianshuai Gao Hongmei Liu Yanxia Ding Hongjun Wang Yanqiang Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第2期121-125,共5页
BACKGROUND: Previous researches suggested that expression level of calbindin D28K mRNA decreased in substantia nigra (SN) of model rats with Parkinson disease (PD), and this might be related to the decrease of an... BACKGROUND: Previous researches suggested that expression level of calbindin D28K mRNA decreased in substantia nigra (SN) of model rats with Parkinson disease (PD), and this might be related to the decrease of anti-degeneration potentials of dopaminergic neurons. OBJECTIVE: To observe expression changes of calbindin D28K in SN dopaminergic neurons during their degeneration and death in midbrain of PD model rats. DESIGN: Completely randomized grouping design SETTING: Department of Neurobiology, Xuzhou Medical College MATERIALS" A total of 92 healthy male SD rats, with the age of 3 months, weighing 200-250 g, were selected from Experimental Animal Center of Xuzhou Medical College [certification: SCXK (su) 2003-0003]. Calbindin D28K(CB), tyroxine hydroxylase (TH), ABC kit, 6-hydroxydopamine (6-OHDA) and Nissl dyes were provided by Sigma Company, and sheep serum was provided by Beijing Zhongshan Company. METHODS: The experiment was carried out in the Neurobiological Center of Xuzhou Medical College from October 2003 to October 2004. ① With lot method, rats were divided into blank control group (n=28), experimental control group (n=-28) and experimental group (n=36). Rats in experimental group were injected with 6-OHDA at right corpus striatum for PD modeling; rats in experimental control group were injected with saline at the same site; rats in blank control group did not give any injections.② On the 7^th, 14^th, 21^st and 28^th days, SN segments on right midbrain from every 5 rats in experimental group were fixed, embedded with paraffin and cut into successively coronary pieces. Rats in other two groups were treated with the same methods and then stained with Nissl to show neuronal form. Meanwhile, CB and TH antibodies staining with immunohistochemistry were used to show CB containing dopaminergic neurons and dopaminergic neurons, and cells were calculated and observed under optic microscope. ③ On the 14^th and 28^th days, every 4 rats in experimental group and every 4 rats in control group were selected to obtain their brains and separate SN on the injured side. Western blot was used to detect expression of calbindin D28K, protein band was scanned with imaging equipment, and data were analyzed with LabWorks software. MAIN OUTCOME MEASURES:① On the 7^th, 14^th, 21^st and 28^th days, Nissl staining results of SN neurons and immunohistochemical staining results of CB and TH antibodies; ② On the 14^th and 28^th days, Western blot results of calbindin D28K in SN neurons, RESULTS; Among 92 rats, 2 rats in experimental group died after 1 day due to 6-OHDA injection and other 90 rats were involved in the final analysis. ①Nissl staining results: On the 7^th day of 6-OHDA injection, most neuronal somas on right SN pars compacta were shown as deep pycnosis or lysis breakage; on the 14^th and 21^st days, amount of neurons was decreased remarkably; on the 28^th day, most neurons in SN pars compacta disappeared. ② Results of immunohistochemical staining: Amount of positive neurons of calbindin D28K in right SN pars compacta was not changed on the 7^th day after 6-OHDA injection; on the 14^th day, the amount was higher in experimental group than that in both control groups (P 〈 0.01) and was decreased till the 21^st day, but it was still higher than that in the two control groups (P 〈 0.05); on the 28^th day, positive neurons of calbindin D28K nearly disappeared, and the amount was lower than that in the two control groups (P 〈 0.01). In addition, on the 7^th day after 6-OHDA injection into corpus striatum, positive TH neurons decreased 24% in right SN, and there was significant difference from that in control groups; on the 14^th, 21^st and 28^th days, positive TH neurons decreased 37%, 46% and 64%, respectively. ③ Western blot results: On the 14'h day after 6-OHDA injection into corpus striatum, expression of calbindin D28K in right SN was higher in experimental group than that in both control groups (P 〈 0.05); however, on the 28^th day, the expression was lower than that in the two control groups (P 〈 0.01 ). CONCLUSION : During degeneration and death of dopaminergic neurons, CB expression in SN pars compacta increases firstly and decreased gradually. 展开更多
关键词 FIGURE expression of calbindin D28K in substantia nigra of model rats with Parkinson disease
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Interventional effect of hirudin on the expression of microtubule-associated protein 2 in peripheral tissue of hematom of model rats with acute intracerebral hemorrhage 被引量:2
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作者 Jiachun Feng Ying Zhang Fang Deng 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第3期230-233,共4页
BACKGROUND: It is suspected that dissociation, destruction or synthetic disorder of microtubule-associated protein 2 (MAP-2) may participate in secondary injury of intracerebral hemorrhage (ICH), and the reason m... BACKGROUND: It is suspected that dissociation, destruction or synthetic disorder of microtubule-associated protein 2 (MAP-2) may participate in secondary injury of intracerebral hemorrhage (ICH), and the reason may be related to thrombin in high concentration after ICH; therefore, the mechanism should be studied further. OBJECTIVE: To explore the effect of hirudin on expression of MAP-2 in peripheral tissue of hematom after ICH and changes of water content in brain tissue and analyze pathogenesis of thrombin in secondary injury after ICH. DESIGN : Completely randomized grouping design and controlled animal study SEn-ING : Department of Neurology, the First Affiliated Hospital of Jilin University MATERIALS : The experiment was carried out in the Neurological Laboratory of the First Affiliated Hospital of Jilin University from April 2003 to April 2004. A number of 80 healthy Wistar rats, of both genders, aged 3-4 months, weighing 250-350 g, were randomly divided into 8 groups: normal control group, 6-hour ICH group, 1-day ICH group, 2-day ICH group, 3-day ICH group, 7-day ICH group, 3-day hirudin group and 7-day hirudin group with 10 in each group. Five rats from each group were selected to measure their water content, and the others were undertaken immunohistochemical stain. Hirudin was produced by Sigma Company, USA, and MAP-2 rabbit-rat polyclonal antibody was provided by Fuzhou Maixin Biotechnology Company Limited. METHODS: ① Model establishing and grouping intervention: Rats in simple ICH group were collected their blood from tails and then inserted with 50 μL non-anticoagulant auto-arterial blood into the cauda of the putamen in right brain within 5 minutes. Rats in hirudin groups were inserted with 10 U hirudin (which was diluted with saline to 20 μL) into local hematom regions within 5 minutes, and the needle was pulled out after 10 minutes. Rats in normal control group were untouched. ② Water content in peripheral tissue of hematom: Based on the ratio between dry weight and wet weight, brain tissue at bleeding side and in right frontal lobe was selected to measure dry and wet weights so as to calculate the water content [(wet weight - dry weight) /wet weight] × 100%.③ Positive expression of MAP-2: Based on immunohistochemical stain, positive MAP-2 cells were regarded as neurons and they were buffy morphological. Positive rate of MAP-2 was calculated, i.e., percentage of positive cells in each sight to total cells in all sights. ④ Statistical analysis: Data among groups were compared with one-way analysis of variance, averages were compared with SNK-q test by each other, and relation between water content and MAP-2 was analyzed with linear regression technique. MAIN OUTCOME MEASURES: Changes of water content and MAP-2 expression in peripheral tissue of hematorn at various time points after ICH and intervention of hirudin. RESULTS: All 80 rats were involved in the final analysis. ①Water content: Water content was increased at day 1, reached peak at day 3 and decreased at day 7. It was (72.31±0.32)%, (77.42±0.53)%, (78.44±0.28)%, (74.10±0.13)%, (74.85±0.51)% and (70.07±0.36)%, respectively in 1-day, 2-day, 3-day and 7-day ICH groups and 3-day and 7-day hirudin groups, which was higher than that in normal control group (63.85±0.41, q=-4.684 3 to -7.262 0, P〈 0.05); that in 2-day and 3-day ICH groups was higher than that in 7-day ICH group (q=-3.053 4, -3.727 0, P 〈 0.05); and that in 3-day and 7-day ICH groups was higher than that in hirudin groups at the same time points (q=-2.965 6, -2.726 4, P 〈 0.05). ②Positive expression of MAP-2: Positive expression of MAP-2 was decreased at 6 hours after ICH, reached the lowest value at day 3 and increased at day 7. Positive rate was (78.60±0.42)%, (60.56±0.74)%, (44.60±0.26)%, (25.45±0.85)%, (32.55±0.64)%, (37.69+0.76)%, (41.75±0.68)%, respectively in 6-hour, 1-day, 2-day, 3-day and 7-day ICH groups and 3-day and 7-day hirudin groups, which was lower than that in normal control group [(96.50±0.33)%, q= -3.074 5 to -8.128 5, P 〈 0.05]. In addition, positive cells of MAP-2 disappeared plentifully at 3-7 days after ICH, stain of positive cells were light, and only stain of plasma was positive. That in 3-day and 7-day hirudin groups was higher than that in ICH groups at the same time points (q= -3.391 8, -2.967 9, P 〈 0.05). Moreover, positive cells of MAP-2 was formed slightly but deeply stained. ③ Results of linear regression: Water content was negatively related to MAP-2 changes at 7 days after ICH (r= -0.894 9, P〈 0.01), i.e., water content was increased with decrease of MAP-2 expression. CONCLUSION : The deterioration of MAP-2 may be involved in the pathogenesis of thrombin within the first week after ICH, and the local administration of hirudin can protect neurons. 展开更多
关键词 ICH Interventional effect of hirudin on the expression of microtubule-associated protein 2 in peripheral tissue of hematom of model
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Topological Expression Model of Satellite Gear Mechanism
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作者 杨平 《Journal of Southwest Jiaotong University(English Edition)》 2005年第1期39-43,共5页
By investigation of the topological characteristics of the kinematic structure of Satellite Gear Mechanism (SGM) with graph theory, the graph model of SGM is analyzed, and a topological expression model between input ... By investigation of the topological characteristics of the kinematic structure of Satellite Gear Mechanism (SGM) with graph theory, the graph model of SGM is analyzed, and a topological expression model between input and output of SGM is established based on systematic design point. Meanwhile, the mathematical expression for SGM is deduced by integrating matrix theory and graph theory; thus, the topological characteristics of the kinematic structure of SGM can be converted into a matrix model, and the topological design problem of SGM into a matrix operation problem. In addition, a brief discussion about the measures for identification of isomorphism of the graph mode is made. 展开更多
关键词 Satellite gear mechanism Graph model Topological expression
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面向PDM的产品及其零部件的EXPRESS模型 被引量:3
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作者 张思荣 谭建荣 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2001年第10期918-925,共8页
对产品及其零部件进行正确建模是 PDM系统实现的前提和关键 .文中针对现有 STEP应用协议存在的局限性进行了合理的扩充 ,建立了产品及产品版本类、产品定义关系类等产品及其零部件的 EXPRESS模型 ,开发了基于该模型的 PDM系统 ,实现了... 对产品及其零部件进行正确建模是 PDM系统实现的前提和关键 .文中针对现有 STEP应用协议存在的局限性进行了合理的扩充 ,建立了产品及产品版本类、产品定义关系类等产品及其零部件的 EXPRESS模型 ,开发了基于该模型的 PDM系统 ,实现了产品的结构管理、配置管理、以及产品相关信息的集成管理 。 展开更多
关键词 产品配置管理 PDM CIMS express模型 零部件
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面向多目标模式的EXPRESS模型转换 被引量:2
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作者 杨子江 黄益民 董金祥 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2005年第4期800-805,共6页
提出一种系统化的模型转换方法,实现EXPRESS模型向多种目标模型的转换文中系统分为模式无关层、半模式相关层与模式相关层,分别处理模式转换中不同阶段的信息论述了EXPRESS模型转换的一些关键技术,包括EXPRESS继承关系和约束在对象模型... 提出一种系统化的模型转换方法,实现EXPRESS模型向多种目标模型的转换文中系统分为模式无关层、半模式相关层与模式相关层,分别处理模式转换中不同阶段的信息论述了EXPRESS模型转换的一些关键技术,包括EXPRESS继承关系和约束在对象模型、关系模型与结构化模型中的表达利用文中方法,可将具体的模型转换归结到某一类别并利用现有框架实现。 展开更多
关键词 express建模语言 数据模型 模式转换
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CHECKING CONSISTENCY IN INFORMATION MODELS BY USING CONSTRAINT PROGRAMMING
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作者 方捷 KAHN Hilary J CARPENTER Andy 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2005年第1期30-37,共8页
This paper addresses the issue of checking consistency in information models. A method based on constraint programming is proposed for identifying inconsistency or proving consistency in information models. The system... This paper addresses the issue of checking consistency in information models. A method based on constraint programming is proposed for identifying inconsistency or proving consistency in information models. The system described here checks information models written in the ISO standard information modelling language EXPRESS. EXPRESS is part of the ISO STEP standard used in the manufacturing and process industries. This paper describes the checking procedure, including EXPRESS model formalization, constraint satisfaction problem (CSP) derivation from the formalized model and satisfaction checking of the derived CSPs. This paper shows a new domain in which constraint programming can be exploited as model verification and validation. 展开更多
关键词 express model constraint programming model verification
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基于语言的企业互操作研究EXPRESS 被引量:3
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作者 吴会波 段国林 《河北工业大学学报》 CAS 北大核心 2012年第2期1-4,共4页
为了较好地实现企业信息互操作,本文提出了一个基于EXPRESS语言的互操作企业建模方法.企业模型构成以产品模型为核心,以过程模型为主导;从视图种类、模型的详细程度和建模过程3个角度定义了企业模型框架;采用国际标准定义的EXPRESS语言... 为了较好地实现企业信息互操作,本文提出了一个基于EXPRESS语言的互操作企业建模方法.企业模型构成以产品模型为核心,以过程模型为主导;从视图种类、模型的详细程度和建模过程3个角度定义了企业模型框架;采用国际标准定义的EXPRESS语言表达所有企业模型信息,给出了完整的企业模型的信息实体来源及组成.结合实例阐述了产品设计阶段、产品信息应用解释模型的具体建立过程.该建模方法能够得到完整且为计算机释读的企业信息,解决了企业互操作方面关键的语法、语义障碍问题. 展开更多
关键词 express语言 企业建模 产品信息 互操作
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基于EXPRESS-G的BAS信息模型拓扑结构浅析 被引量:3
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作者 张超 马小军 《科技通报》 北大核心 2016年第2期96-99,共4页
基于智能建筑中典型的BAS,在CAD设计的基础上,将EXPRESS-G图形语言运用在BAS设计过程中,以达到在设计与施工过程中减少重复劳动,简化设计过程,降低成本的目的。建立一个包含设备列表、网络拓扑结构、以及点表和操作序列的BAS信息模型,... 基于智能建筑中典型的BAS,在CAD设计的基础上,将EXPRESS-G图形语言运用在BAS设计过程中,以达到在设计与施工过程中减少重复劳动,简化设计过程,降低成本的目的。建立一个包含设备列表、网络拓扑结构、以及点表和操作序列的BAS信息模型,基于此模型可以在建筑的全生命周期中使BAS模型在符合IFC标准的前提下保持单向传递性,利用创建出的模型可以直接使用能耗仿真及维修管理系统等的应用程序,并且能在调试和使用过程中直接从中提取各自所需的数据信息。 展开更多
关键词 BAS express-G 信息模型 IFC 拓扑结构
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自噬相关基因在肺纤维化模型中的表达:生物信息学分析及实验验证
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作者 刘可新 郝凯敏 +1 位作者 庄文越 李正祎 《中国组织工程研究》 北大核心 2026年第5期1129-1138,共10页
背景:自噬对上皮细胞、成纤维细胞和肌成纤维细胞之间的应激作用与肺纤维化的形成过程密切相关。目的:筛选肺纤维化患者基因水平变化与自噬相关的基因,并探究其与肺纤维化患者预后的关联,以期为临床干预肺纤维化提供新的靶点。方法:以GS... 背景:自噬对上皮细胞、成纤维细胞和肌成纤维细胞之间的应激作用与肺纤维化的形成过程密切相关。目的:筛选肺纤维化患者基因水平变化与自噬相关的基因,并探究其与肺纤维化患者预后的关联,以期为临床干预肺纤维化提供新的靶点。方法:以GSE70866下载的基因表达谱数据集为训练集,利用R语言对肺纤维化患者和正常健康者之间基因表达进行差异分析并与自噬相关基因取交集,鉴定出变化最为显著的差异基因。运用多种分析方法筛选出关键预后基因,并构建基因预后模型。根据肺纤维化患者的风险评分分为高风险组和低风险组,应用Siena cohort和Leuven cohort验证集验证预后模型的有效性。并通过转化生长因子β1诱导HFL-1细胞(人胚肺成纤维细胞)建立肺纤维化细胞模型以及博莱霉素气管滴注建立小鼠肺纤维化动物模型验证预后基因的表达。结果与结论:①肺纤维化组织和正常组织之间存在2650个差异基因,其中与自噬相关基因有34个发生显著变化;②Siena cohort和Leuven cohort验证集的Kaplan-Meier生存分析曲线显示,高风险组的存活率明显比低风险组低;③筛选出3个与预后相关的自噬基因:骨髓瘤病病毒癌基因、趋化因子配体2、GABAA型受体相关蛋白样1;④体内外研究均显示与对照组相比,肺纤维化模型组骨髓瘤病病毒癌基因和趋化因子配体2 mRNA及蛋白表达显著升高(P<0.01,P<0.05),而GABAA型受体相关蛋白样1 mRNA及蛋白表达有所降低(P<0.001);⑤结论:通过生物信息学方法分析了3个自噬相关基因在肺纤维化中的表达及其与肺纤维化患者预后的相关性,构建的预后模型对肺纤维化患者1,2,3年生存率具有良好的预测能力;并且通过体内和体外模型验证了在肺纤维化细胞和组织中骨髓瘤病病毒癌基因和趋化因子配体2呈高水平表达,GABAA型受体相关蛋白样1呈低水平表达。 展开更多
关键词 肺纤维化 自噬 生物信息学 差异表达基因 预后模型 R语言 博莱霉素 TGF-β1
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两种Express数据模型的转换方法 被引量:3
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作者 杨子江 李善平 《计算机工程》 EI CAS CSCD 北大核心 2000年第1期63-64,70,共3页
针对Express语言的特点,结合Step中性文件的读写过程,讨论了两种不同的转换方法:面向结构的方法与面向约束的方法。
关键词 express语言 中性文件 数据模型 模型转换
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基于STEP标准的统一BOM模型的EXPRESS语言描述 被引量:1
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作者 汪洋 钱贵平 韩承双 《机械工程师》 2008年第7期132-134,共3页
在统一BOM模型的EXPRESS-G图基础上,从引用通用资源、类型定义、物料项实体定义、物料项关系实体定义4个方面详细阐述了基于STEP标准的统一BOM模型的EXPRESS语言描述。构建了产品、零部件、中间件、原材料与毛坯、资源和文档六类物料项... 在统一BOM模型的EXPRESS-G图基础上,从引用通用资源、类型定义、物料项实体定义、物料项关系实体定义4个方面详细阐述了基于STEP标准的统一BOM模型的EXPRESS语言描述。构建了产品、零部件、中间件、原材料与毛坯、资源和文档六类物料项实体,描述了具体产品的BOM、具体产品由下级具体零部件构成的层次关系和具体部件由下级子部件、零件及原材料(毛坯)构成的层次关系,并给出了具体实例。 展开更多
关键词 STEP标准 统一BOM模型 express 物料项 物料项关系
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Expression, purification and activity assay of recombinant human thymidylate synthase
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作者 李超 郭莹 +5 位作者 田超 周受辛 闫汝峰 张志丽 王孝伟 刘俊义 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2013年第2期173-176,共4页
Thymidylate synthase (TS, E.C.2.1.1.45) catalyzes a critical reaction in the only pathway of de novo synthesis of thymidylate (dTMP) in human cells, and is an important target of chemotherapy. To evaluate the inhi... Thymidylate synthase (TS, E.C.2.1.1.45) catalyzes a critical reaction in the only pathway of de novo synthesis of thymidylate (dTMP) in human cells, and is an important target of chemotherapy. To evaluate the inhibitory activities of novel compounds to TS, a convenient method of activity assay using 6x His-tagged recombinant human TS (rhTS) was established and 49 novel synthetic folate analogues were screened to discover potential TS inhibitors. During the process, 4 novel compounds were found to effectively inhibit TS, while the IC 50 of a positive control raltitrexed was 3.4 μM in this assay. 展开更多
关键词 Thymidylate synthase inhibitors Recombinant protein expression Ni-resin column Screening model
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基于表达式树的Modelica单位检查和推导 被引量:1
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作者 赵建军 陈闻豪 《计算机辅助工程》 2013年第4期76-81,共6页
为提高多领域物理系统统一建模中复杂模型的质量和可靠性,介绍Modelica对单位的支持方式以及单位之间的换算和运算规则,基于对表达式树的遍历,给出单位检查和推导机制的实现方案.通过分析该方案的时间复杂度,优化影响其效率的主要因素.... 为提高多领域物理系统统一建模中复杂模型的质量和可靠性,介绍Modelica对单位的支持方式以及单位之间的换算和运算规则,基于对表达式树的遍历,给出单位检查和推导机制的实现方案.通过分析该方案的时间复杂度,优化影响其效率的主要因素.在MWorks上实现该方案,并通过Modelica标准库中的模型证明该方案可行. 展开更多
关键词 modelICA 表达式树 多领域物理系统 统一建模 模型可靠性 MWorks
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EXPRESS向OWL2本体模型自动转换研究 被引量:4
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作者 袁满 刘峰 《吉林大学学报(信息科学版)》 CAS 2018年第1期69-77,共9页
为解决EXPRESS向本体转换中存在通用性差、缺乏映射规则的形式化和自动转换等问题,在不依赖领域情况下,提出两种语言间映射的形式化规则和自动转换算法。该映射规则和算法实现了基于EXPRESS的石油勘探开发国际标准数据模型(Epicentre)... 为解决EXPRESS向本体转换中存在通用性差、缺乏映射规则的形式化和自动转换等问题,在不依赖领域情况下,提出两种语言间映射的形式化规则和自动转换算法。该映射规则和算法实现了基于EXPRESS的石油勘探开发国际标准数据模型(Epicentre)向本体的自动转化。采用Jena推理验证了所构建的Epicentre本体的准确性、完整性和一致性。结果表明,该映射规则与自动化算法的有效性和普适性。 展开更多
关键词 express语言 本体 映射形式化 自动转换算法 Epicentre模型 Jena推理
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基于AutoCAD Express线型自定义的矿图模板制作 被引量:3
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作者 张志刚 董长吉 第伟伟 《煤炭技术》 CAS 北大核心 2011年第1期73-74,共2页
对比了形编译和基于Express Tools工具的线型自定义,着重介绍了利用Express Tools工具进行线型自定义的具体方法和步骤。通过将定义的煤矿制图常用的线型和图层等设置保存为模板,可以极大地提高制图效率,减轻绘图人员的工作量。
关键词 AUTOCAD express 二次开发 自定义 矿图模板
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武威农村地区“1+2+N”模式对学前儿童语言表达能力提升效果的调研
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作者 樊超 段晓静 《黑龙江科学》 2026年第1期77-79,共3页
为破解农村地区学前儿童语言表达能力发展滞后难题,验证“1+2+N”模式对学前儿童语言表达能力的提升效果,选取武威市3个县区6所农村幼儿园的240名3~6岁儿童为研究对象,综合运用实验法、问卷调查法及访谈法开展为期7个月的干预实验并进... 为破解农村地区学前儿童语言表达能力发展滞后难题,验证“1+2+N”模式对学前儿童语言表达能力的提升效果,选取武威市3个县区6所农村幼儿园的240名3~6岁儿童为研究对象,综合运用实验法、问卷调查法及访谈法开展为期7个月的干预实验并进行前后测对比研究。结果显示,实施“1+2+N”模式后,实验组儿童的语言表达能力总分提升21.43分,显著高于对照组,在词汇表达、语法运用、语用沟通三大核心维度均取得跨越式进步。其中,4~5岁儿童的提升率最高。N类课程中,家园共育类课程与儿童语言能力的相关性最强。“1+2+N”模式可有效弥补农村学前教育资源短板,对提升儿童语言表达能力具有显著效果,为民族地区及农村地区学前儿童语言发展提供了可复制、可推广的实践方案。 展开更多
关键词 武威农村 “1+2+N”模式 学前儿童 语言表达能力 农村学前教育
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