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板栗2-ODD基因家族的鉴定及其在干旱胁迫下的表达分析
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作者 曾扬鹃 杨涌 +2 位作者 郭江辉 张海娥 曹飞 《山东农业科学》 北大核心 2025年第4期1-13,共13页
2-酮戊二酸依赖性双加氧酶(2-ODD)家族是植物中第二大酶家族,在调控植物对逆境的响应中具有重要作用。本研究利用生物信息学方法从板栗基因组中鉴定出123个Cm2-ODD基因家族成员,同时分析了它们的染色体分布、蛋白理化性质、保守基序、... 2-酮戊二酸依赖性双加氧酶(2-ODD)家族是植物中第二大酶家族,在调控植物对逆境的响应中具有重要作用。本研究利用生物信息学方法从板栗基因组中鉴定出123个Cm2-ODD基因家族成员,同时分析了它们的染色体分布、蛋白理化性质、保守基序、基因结构、共线性基因与顺式作用元件等以及在干旱胁迫下的表达情况。结果发现,Cm2-ODD家族蛋白都含有保守的2OG-FeⅡ_Oxy结构域与保守的DIOX_N结构域,都为亲水性蛋白;Cm2-ODD基因家族成员大多拥有保守基序Motif 1—Motif 9,仅部分含有Motif 10,表明Cm2-ODD蛋白功能可能相对保守。共线性分析发现板栗基因组内Cm2-ODD基因家族可能正在受到纯化选择,2-ODD基因家族的大量复制可能发生在单、双子叶植物分化后。密码子偏好性分析显示Cm2-ODD基因家族偏好以A或U结尾。顺式作用元件分析结果显示,Cm2-ODD基因家族含有较多脱落酸和干旱响应元件,推测其功能可能与板栗抵御干旱胁迫相关;同时转录组分析证明干旱胁迫下Cm2-ODD基因家族有13个成员的表达量受到明显影响,其中Cm2-ODD19和Cm2-ODD16基因明显上调表达。 展开更多
关键词 板栗 Cm2-odd基因家族 生物信息学分析 干旱胁迫 基因表达
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The Characterization of Self-adjoint Domains of Two-interval Odd Order Differential Operators
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作者 WANG Linyu HAO Xiaoling LI Kun 《数学进展》 北大核心 2025年第4期784-802,共19页
In this paper,we give a complete characterization of all self-adjoint domains of odd order differential operators on two intervals.These two intervals with all four endpoints are singular(one endpoint of each interval... In this paper,we give a complete characterization of all self-adjoint domains of odd order differential operators on two intervals.These two intervals with all four endpoints are singular(one endpoint of each interval is singular or all four endpoints are regulars are the special cases).And these extensions yield"new"self-adjoint operators,which involve interactions between the two intervals. 展开更多
关键词 self-adjoint domain odd order differential operator two-interval
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Evaluating log odds of positive lymph nodes as a prognostic tool in differentiated gastric cancer:A retrospective study
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作者 Ming-Cong Deng Ken Chen +20 位作者 Qi-Mei Bao Yi-Xing Huang Chun-Kai Zhang Yu-Ke Zhong Han-Yi He Dan Zu Chen Liang Hai-Dong Liu Yang-Chan Hu Guo-Xia Liu Yan-Hua He Wei-Xing Wu Jing-Nan Zhou Yao-Shu Teng Ji Jing Yin Shi Clive Yik-Sham Chung Chen-Huan Yu Yi-An Du Zu Ye Xiang-Dong Cheng 《World Journal of Gastroenterology》 2025年第21期61-78,共18页
BACKGROUND The log odds of positive lymph nodes(LODDS)are correlated with survival outcomes in gastric cancer(GC)patients.However,the prognostic value across different tumor differentiation levels remains unclear.AIM ... BACKGROUND The log odds of positive lymph nodes(LODDS)are correlated with survival outcomes in gastric cancer(GC)patients.However,the prognostic value across different tumor differentiation levels remains unclear.AIM To evaluate the independent prognostic value of LODDS and the stratified predictive efficacy in GC patients with different histologic differentiations.METHODS We conducted a retrospective analysis of 2103 GC patients who underwent radical gastrectomy at Zhejiang Cancer Hospital.The prognostic value of LODDS was compared with that of other lymph node-based metrics,including the pathologic N stage,number of positive lymph nodes,number of total lymph nodes,and lymph node ratio,stratified by tumor differentiation.RESULTS LODDS was identified as an independent prognostic factor for overall survival in moderately to poorly differentiated GC patients.LODDS demonstrated superior predictive accuracy over other lymph node metrics.A nomogram incorporating LODDS,age,carbohydrate antigen(CA)125,carcinoembryonic antigen,and tumor differentiation showed good predictive accuracy(C-index=0.703).A higher LODDS was significantly associated with an increased risk of recurrence or metastasis,poorly differentiated tumors,advanced cancer,mucinous gastric adenocarcinoma,nerve invasion,and vascular tumor thrombus.Additionally,LODDS was positively correlated with the tumor markers CA19-9,CA72-4,CA125,and CA242(all P<0.05).CONCLUSION LODDS is an independent prognostic indicator for patients with moderately and poorly differentiated GC,and its predictive performance is superior to that of other models. 展开更多
关键词 Gastric cancer Log odds of positive lymph nodes Tumor differentiation Tumor marker Overall survival
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A triple-band miniaturized end-fire antenna based on odd-mode spoof surface plasmonic polariton waveguide resonator
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作者 BAI Yukun MAO Mengqun 《Optoelectronics Letters》 2025年第8期462-467,共6页
A triple-band miniaturized end-fire antenna based on the odd modes of spoof surface plasmonic polariton(SSPP)waveguide resonator is proposed in this paper.To meet the ever increasing demand for more communication chan... A triple-band miniaturized end-fire antenna based on the odd modes of spoof surface plasmonic polariton(SSPP)waveguide resonator is proposed in this paper.To meet the ever increasing demand for more communication channels and less antenna sizes,multi-band antennas are currently under intensive investigation.By a novel feeding method,three odd modes are excited on an SSPP waveguide resonator,which performs as an end-fire antenna operating at three bands,7.15-7.26 GHz,11.6-12.2 GHz and 13.5-13.64 GHz.It exhibits reasonably high and stable maximum gains of 5.26 dBi,7.97 dBi and 10.1 dBi and maximum efficiencies of 64%,92%and 98%at the three bands,respectively.Moreover,in the second band,the main beam angle shows a frequency dependence with a total scanning angle of 19°.The miniaturized triple-band antenna has a great potential in wireless communication systems,satellite communication and radar systems. 展开更多
关键词 odd modes waveguide resonatorwhich triple band antenna end fire antenna feeding methodthree spoof surface plasmonic polariton sspp waveguide communication channels miniaturized antenna
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A New Extension Odd Generalized Exponential Model Using Type-Ⅱ Progressive Censoring and Its Applications in Engineering and Medicine
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作者 Zohra A.Esaadi Rabab S.Gomaa +2 位作者 Beih S.El-Desouky Ehab M.Almetwally Alia M.Magar 《Computer Modeling in Engineering & Sciences》 2025年第8期2063-2097,共35页
A new extended distribution called the Odd Exponential Generalized Exponential-Exponential distribution(EOEGE-E)is proposed based on generalization of the odd generalized exponential family(OEGE-E).The statistical pro... A new extended distribution called the Odd Exponential Generalized Exponential-Exponential distribution(EOEGE-E)is proposed based on generalization of the odd generalized exponential family(OEGE-E).The statistical properties of the proposed distribution are derived.The study evaluates the accuracy of six estimation methods under complete samples.Estimation techniques include maximumlikelihood,ordinary least squares,weighted least squares,maximumproduct of spacing,Cramer vonMises,and Anderson-Darling methods.Twomethods of estimation for the involved parameters are considered based on progressively type Ⅱ censored data(PTⅡC).These methods are maximum likelihood and maximum product of spacing.The proposed distribution’s effectiveness was evaluated using different data sets from various fields.The proposed distribution provides a better fit for these datasets than existing probability distributions. 展开更多
关键词 odd generalized exponential distribution likelihood and product of spacing progressive censoring progressive typeⅡcensoring
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A Prognostic Nomogram Based on Log Odds of Positive Lymph Nodes for Patients with Gastroenteropancreatic Neuroendocrine Tumors
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作者 Jinsheng Xu Yujie Xu 《Proceedings of Anticancer Research》 2024年第6期223-238,共16页
Objective: To explore the prognostic value of log odds of positive lymph nodes (LODDS) in patients with gastroenteropancreatic neuroendocrine tumors (GEPNET) and to develop nomograms based on LODDS for predicting 1-ye... Objective: To explore the prognostic value of log odds of positive lymph nodes (LODDS) in patients with gastroenteropancreatic neuroendocrine tumors (GEPNET) and to develop nomograms based on LODDS for predicting 1-year, 3-year, and 5-year overall survival (OS) and cancer-specific survival (CSS). Methods: This retrospective cohort study was based on the Surveillance, Epidemiology, and End Results (SEER) Program. Demographic data, clinical data, and survival status were extracted, with endpoints of OS and CSS. Multivariate Cox proportional hazards regression analysis assessed predictors associated with OS and CSS, with hazard ratios (HRs) and 95% confidence intervals (CIs) evaluated. Nomogram performance was assessed by calculating the area under the receiver operating characteristic (ROC) curve (AUC). Results: A total of 1,673 patients were included and divided into a training set (n = 1,172) and a testing set (n = 501). Multivariate Cox proportional hazards regression analyses identified LODDS as an independent prognostic factor for OS (HR = 1.79, 95% CI: 1.44-2.24) and CSS (HR = 1.81, 95% CI: 1.41-2.31). The OS and CSS nomograms, developed from multivariate Cox regression analyses, showed good performance, with AUCs of 0.858, 0.878, and 0.852 for predicting 1-year, 3-year, and 5-year OS, and AUCs of 0.859, 0.887, and 0.865 for 1-year, 3-year, and 5-year CSS in the testing set. The nomograms are accessible online (OS: https://zhmte.shinyapps.io/DynNomapp/;CSS: https:// zhmty.shinyapps.io/DynNomapp/). Conclusions: LODDS serves as an independent prognostic factor in GEPNET. Online nomograms based on LODDS demonstrated effective performance in predicting OS and CSS in GEPNET patients, providing a convenient tool for clinical application. 展开更多
关键词 Log odds of positive lymph nodes Online dynamitic nomograms Overall survival Cancer-specific survival
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父母心理控制与ODD症状儿童抑郁、攻击行为的关系 被引量:13
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作者 蔺秀云 李龙凤 +3 位作者 黎燕斌 王中会 陈琦 方晓义 《心理发展与教育》 CSSCI 北大核心 2014年第6期635-645,共11页
以北京市、山东省和云南省14所小学中的340名有对立违抗障碍(Oppositional Defiant Disorder,ODD)症状的儿童及其158名班主任为被试,收集了儿童自己填写的父母心理控制、自尊、抑郁量表,班主任评估的儿童攻击行为量表,用以考察父亲与母... 以北京市、山东省和云南省14所小学中的340名有对立违抗障碍(Oppositional Defiant Disorder,ODD)症状的儿童及其158名班主任为被试,收集了儿童自己填写的父母心理控制、自尊、抑郁量表,班主任评估的儿童攻击行为量表,用以考察父亲与母亲心理控制对ODD症状儿童抑郁、攻击行为的不同影响,以及自尊在其中的中介作用和儿童性别的调节作用。结果发现:(1)与有ODD症状的女孩相比,具有ODD症状的男孩人数更多,抑郁、攻击行为问题更为严重,自尊也更差;(2)父亲对男孩的心理控制显著多于女孩,而母亲对男孩、女孩的心理控制没有显著差异;(3)父亲和母亲心理控制与ODD症状儿童的抑郁、攻击行为都呈显著正相关且父亲心理控制能显著预测儿童的抑郁和攻击行为,而母亲心理控制能显著的预测攻击行为;(4)自尊在父亲心理控制与ODD症状儿童的抑郁、母亲心理控制与儿童的攻击行为之间均起部分中介作用,在父亲心理控制与儿童的攻击行为、母亲心理控制与儿童的抑郁之间均起完全中介作用。 展开更多
关键词 odd症状儿童 父母心理控制 自尊 抑郁 攻击行为
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Kumaraswamy-Odd Rayleigh-G Family of Distributions with Applications
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作者 Jamilu Yunusa Falgore Sani Ibrahim Doguwa 《Open Journal of Statistics》 2020年第4期719-734,共16页
We propose a new generator of continuous distributions with at least four positive parameters called the Kumaraswamy-Odd Rayleigh-G family. Some special cases were presented. The plots of the Kumaraswamy Odd Rayleigh ... We propose a new generator of continuous distributions with at least four positive parameters called the Kumaraswamy-Odd Rayleigh-G family. Some special cases were presented. The plots of the Kumaraswamy Odd Rayleigh Log-Logistic (</span><i><span style="font-family:Verdana;">KORLL</span></i><span style="font-family:Verdana;">) distribution indicate that the distribution can take many shapes depending on the parameter values. The negative skewness and kurtosis indicates that the distribution has li</span><span style="font-family:Verdana;">ghter tails than the normal distribution. The Monte Carlo simulation results indicate that the estimated biases decrease when the sample size increases. Furthermore, </span></span><span style="font-family:Verdana;">the root mean squared error estimates decay</span><span style="font-family:""><span style="font-family:Verdana;"> towards zero as the sample size increases. This part shows the consistency of the maximum likelihood estimators. From the considered analytical measures, the new </span><i><span style="font-family:Verdana;">KORLL</span></i><span style="font-family:Verdana;"> provides </span></span><span style="font-family:Verdana;">the best fit to the analysed five real data sets indicating that this new model outclasses its competitors. 展开更多
关键词 odd Rayleigh-G Family Kumuraswamy odd Rayleigh-G Family Kumuraswamy odd Rayleigh-Loglogistic Distribution Monte Carlo Simulation SKEWNESS
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基于Odds-Matrix算法的中长期电量组合预测方法及其应用 被引量:5
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作者 欧阳森 冯天瑞 +1 位作者 李翔 王克英 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2014年第8期39-44,共6页
中长期电量的组合预测存在权重选择困难,适应性、抗干扰性较差的问题.文中结合目前广泛应用的组合预测技术,设计了以Odds-Matrix算法为核心的Odds-Matrix组合预测方法.该组合预测方法利用Odds-Matrix算法对单一预测模型的有效性进行定... 中长期电量的组合预测存在权重选择困难,适应性、抗干扰性较差的问题.文中结合目前广泛应用的组合预测技术,设计了以Odds-Matrix算法为核心的Odds-Matrix组合预测方法.该组合预测方法利用Odds-Matrix算法对单一预测模型的有效性进行定量分析,用权重概率分布函数来描述各个方法的优劣,然后根据权重进行单一预测模型的筛选和组合.利用实际数据对所设计的Odds-Matrix组合预测方法进行测试,结果表明,文中预测方法的精确度较其他常用组合预测法较高,说明该方法具有较强的适应性与抗干扰性. 展开更多
关键词 电量预测 odds-Matrix算法 组合预测 模型筛选
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家庭教养方式与流动儿童ODD行为表现的关系
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作者 刘振敏 《中华家教》 2024年第2期85-94,共10页
本文采用问卷法对北京市218名有对立违抗障碍(ODD)行为表现的流动儿童进行调查,测查其家庭教养方式和ODD行为表现的关系。结果显示:(1)ODD行为表现在教养方式上差异显著;(2)ODD行为表现在回应性和要求性上差异显著;(3)回应性、要求性和... 本文采用问卷法对北京市218名有对立违抗障碍(ODD)行为表现的流动儿童进行调查,测查其家庭教养方式和ODD行为表现的关系。结果显示:(1)ODD行为表现在教养方式上差异显著;(2)ODD行为表现在回应性和要求性上差异显著;(3)回应性、要求性和ODD行为表现具有显著相关。研究结果表明,父母采用积极有效的家庭教养方式,重视对儿童的积极情感回应,采用正向而恰当的规则教导,掌握正确的奖惩措施,保持良好的亲子沟通,对促进流动儿童心理健康发展具有指导意义。 展开更多
关键词 家庭教养方式 对立违抗障碍 回应性 要求性
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odds ratio在医学动物实验中的应用
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作者 迟琼 邹泽红 +1 位作者 傅意玲 陶爱林 《中国药理学通报》 CAS CSCD 北大核心 2010年第3期408-410,共3页
目的分析odds ratio在医学动物实验中的应用现状。方法以医学动物实验中常用动物模型及优势比或odds ra-tio为检索式进行搜索,分别对比分析中外数据库中7种动物模型实验中应用odds ratio的状况。同时,给出范例,说明OR值的计算方法及不... 目的分析odds ratio在医学动物实验中的应用现状。方法以医学动物实验中常用动物模型及优势比或odds ra-tio为检索式进行搜索,分别对比分析中外数据库中7种动物模型实验中应用odds ratio的状况。同时,给出范例,说明OR值的计算方法及不同结果的实际意义。结果动物模型实验中使用OR值作为统计指标的寥寥无几。结论OR值的重要性在国内没有得到足够的关注。 展开更多
关键词 数据库 动物模型 优势比 odds RATIO 关联强度 检索式
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On the Problem of All Equal Positive Odd Number Solutions of the Dissemination of the Ends' Guess 被引量:1
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作者 刘元宗 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第2期108-109,共2页
The thesis is concerned with the problem of the dissemination of the Ends’ guess and offers the formula of all equal positive odd number solutions.
关键词 Ends’ guess DISSEMINATION all equal positive odd number solutions
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Oddi括约肌收缩运动与十二指肠MMC相关性的实验研究 被引量:1
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作者 王洪江 《中国应用生理学杂志》 CAS CSCD 北大核心 2004年第4期357-358,379,共3页
目的确定Oddi括约肌收缩运动与十二指肠移行性运动综合波(migratingmotorcomplex,MMC)的相互关系,提高对胆道机能失调性疾病的诊断或药物对Oddi括约肌影响的评价。方法四只杂种成犬行十二指肠Thomas造瘘,微量灌流法连续测定十二指肠和O... 目的确定Oddi括约肌收缩运动与十二指肠移行性运动综合波(migratingmotorcomplex,MMC)的相互关系,提高对胆道机能失调性疾病的诊断或药物对Oddi括约肌影响的评价。方法四只杂种成犬行十二指肠Thomas造瘘,微量灌流法连续测定十二指肠和Oddi括约肌收缩运动。结果Oddi括约肌伴随十二指肠MMC呈周期性收缩运动,平均基础压、振幅和收缩频率在十二指肠MMC的1期,不受十二指肠收缩的影响,相对稳定。与2期或3期相比,差异显著(P〈0.01)。结论阐述Oddi括约肌收缩功能或研究药物对Oddi括约肌的作用时,应注意十二指肠对Oddi括约肌的影响。 展开更多
关键词 oddI括约肌 十二指肠 移行性运动综合波
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基于指数分布的比例odds模型次序统计量的随机性质
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作者 张艺馨 王丙参 《德州学院学报》 2017年第4期7-9,21,共4页
给出几种常见序关系的定义,在比例odds模型的框架下,当分布函数替换为指数分布时,对其次序统计量作了随机比较.
关键词 随机序 比例odds模型 次序统计量
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基于比例odds模型最小次序统计量的随机比较
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作者 张艺馨 《天水师范学院学报》 2016年第2期16-18,共3页
在比例odds模型的框架下,对它的最小次序统计量作了随机比较,包括似然比序,失效率序和随机序.
关键词 随机序 反失效率序 似然比序 比例odds模型
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果蝇odd蛋白的原核表达及多克隆抗体的制备研究 被引量:1
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作者 张义 叶湘漓 +8 位作者 鲁建鑫 彭佩莹 赵阳 江志钢 李发祥 王跃群 袁婺洲 吴秀山 邓云 《激光生物学报》 CAS CSCD 2011年第6期778-781,共4页
odd是一个新发现的心脏特异表达基因。为了进一步研究odd在心脏发育中的功能,根据已报道的odd基因序列,以果蝇cDNA文库为模板进行PCR扩增,将所得的odd部分编码区序列连接到pET-28a载体上构建原核表达载体;重组子经酶切测序鉴定后,转化... odd是一个新发现的心脏特异表达基因。为了进一步研究odd在心脏发育中的功能,根据已报道的odd基因序列,以果蝇cDNA文库为模板进行PCR扩增,将所得的odd部分编码区序列连接到pET-28a载体上构建原核表达载体;重组子经酶切测序鉴定后,转化到大肠杆菌BL21菌株,IPTG诱导融合蛋白表达,Ni-IDA凝胶柱亲和纯化,纯化后的His-odd融合蛋白免疫新西兰大白兔以制备多克隆抗体,Western Blot检测抗体活性。结果表明,获得了odd原核表达重组融合蛋白以及高效价的、特异性兔抗Odd多克隆抗体,为后续的odd功能研究奠定了基础。 展开更多
关键词 odd 融合蛋白 原核表达 多克隆抗体
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急性胰腺炎时Oddi括约肌的生长抑素的表达及其作用 被引量:4
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作者 徐赫一 高丽娟 陈平 《内蒙古医科大学学报》 2014年第6期487-490,496,共5页
目的:探讨急性胰腺炎时Oddi括约肌(SO)生长抑素(SST)的表达及其作用。方法::采用逆行胰胆管牛磺胆酸钠注射造成豚鼠急性胰腺炎动物模型,随机分为正常对照组、急性胰腺炎模型组和生长抑素预防性治疗组。观察三组胰腺组织及SO组织病理学... 目的:探讨急性胰腺炎时Oddi括约肌(SO)生长抑素(SST)的表达及其作用。方法::采用逆行胰胆管牛磺胆酸钠注射造成豚鼠急性胰腺炎动物模型,随机分为正常对照组、急性胰腺炎模型组和生长抑素预防性治疗组。观察三组胰腺组织及SO组织病理学改变和外周血淀粉酶及脂肪酶水平;免疫组化检测三组SO内SST的表达情况。结果:急性胰腺炎豚鼠均见整个胰腺肿大,质软,部分肿大胰腺散在有黄白色脂肪坏死灶。镜下见广泛细胞变性,间质水肿,炎性细胞浸润。部分伴广泛腺泡细胞及胰岛细胞坏死,腺体内片状间质出血斑;生长抑素预防性治疗的急性胰腺炎豚鼠胰腺病理组织学较AP时组织水肿减轻,细胞变性和坏死明显减少,评分明显低于急性胰腺炎组,P<0.05。急性胰腺炎时SO内SST的表达减少。结论:急性胰腺炎的发生静脉给予SST,维持了豚鼠急性胰腺炎后循环中的SST水平,SO内SST神经分泌明显减少,显著防止了胰腺炎症病变。 展开更多
关键词 odd括约肌 急性胰腺炎 生长抑素
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Filtration Structure of Finite-Dimensional Special Odd Hamiltonian Superalgebras in Prime Characteristic 被引量:5
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作者 何英华 刘文德 李彬 《Journal of Beijing Institute of Technology》 EI CAS 2009年第4期488-491,共4页
The filtration structure of finite-dimensional special odd Hamilton superalgebras over a field of prime characteristic was studied. By determining ad-nilpotent dements in the even part, the natural filtration of speci... The filtration structure of finite-dimensional special odd Hamilton superalgebras over a field of prime characteristic was studied. By determining ad-nilpotent dements in the even part, the natural filtration of special odd Hamiltonian superalgebras is proved to be invariant. Using this result, the special odd Hamilton superalgebras is classified. Finally, the automorphism group of the restricted special odd Hamilton superalgebras is determined. 展开更多
关键词 finite-dimensional special odd Hamilton superalgebras ad-nilpotent elements FILTRATION
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Optimum design of equivalent accelerated life testing plans based on proportional hazards-proportional odds model 被引量:3
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作者 Tingting Huang Tongmin Jiang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第5期871-878,共8页
The optimum design of equivalent accelerated life testing plan based on proportional hazards-proportional odds model using D-optimality is presented. The defined equivalent test plan is the test plan that has the same... The optimum design of equivalent accelerated life testing plan based on proportional hazards-proportional odds model using D-optimality is presented. The defined equivalent test plan is the test plan that has the same value of the determinant of Fisher information matrix. The equivalent test plan of step stress accelerated life testing (SSALT) to a baseline optimum constant stress accelerated life testing (CSALT) plan is obtained by adjusting the censoring time of SSALT and solving the optimization problem for each case to achieve the same value of the determinant of Fisher information matrix as in the baseline optimum CSALT plan. Numer- ical examples are given finally which demonstrate the equivalent SSALT plan to the baseline optimum CSALT plan reduces almost half of the test time while achieving approximately the same estimation errors of model parameters. 展开更多
关键词 equivalent test plan proportional hazards-proportional odds (PH-PO) model D-OPTIMALITY constant stress step stress accelerated life testing (ALT).
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Development and validation of prognostic nomogram based on log odds of positive lymph nodes for patients with gastric signet ring cell carcinoma 被引量:4
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作者 Zijie Xu Jing Jing Guiliang Ma 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2020年第6期778-793,共16页
Objective: Our aims were to establish novel nomogram models, which directly targeted patients with signet ring cell carcinoma(SRC), for individualized prediction of overall survival(OS) rate and cancer-specific surviv... Objective: Our aims were to establish novel nomogram models, which directly targeted patients with signet ring cell carcinoma(SRC), for individualized prediction of overall survival(OS) rate and cancer-specific survival(CSS).Methods: We selected 1,365 SRC patients diagnosed from 2010 to 2015 from Surveillance, Epidemiology and End Results(SEER) database, and then randomly partitioned them into a training cohort and a validation cohort.Independent predicted indicators, which were identified by using univariate testing and multivariate analyses, were used to construct our prognostic nomogram models. Three methods, Harrell concordance index(C-index), receiver operating characteristics(ROC) curve and calibration curve, were used to assess the ability of discrimination and predictive accuracy. Integrated discrimination improvement(IDI), net reclassification improvement(NRI) and decision curve analysis(DCA) were used to assess clinical utility of our nomogram models.Results: Six independent predicted indicators, age, race, log odds of positive lymph nodes(LODDS), T stage, M stage and tumor size, were associated with OS rate. Nevertheless, only five independent predicted indicators were associated with CSS except race. The developed nomograms based on those independent predicted factors showed reliable discrimination. C-index of our nomogram for OS and CSS was 0.760 and 0.763, which were higher than American Joint Committee on Cancer(AJCC) 8 th edition tumor-node-metastasis(TNM) staging system(0.734 and 0.741, respectively). C-index of validation cohort for OS was 0.757 and for CSS was 0.773. The calibration curves also performed good consistency. IDI, NRI and DCA showed the nomograms for both OS and CSS had a comparable clinical utility than the TNM staging system.Conclusions: The novel nomogram models based on LODDS provided satisfying predictive ability of SRC both in OS and CSS than AJCC 8 th edition TNM staging system alone. 展开更多
关键词 Log odds of positive lymph nodes NOMOGRAMS PROGNOSIS signet ring cell
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