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Soliton Solutions of a Coupled KdV System via Backlund Transformation
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作者 CAO Xifang WU Yiheng +2 位作者 LU Yi XU Wenjing XIA Yutong 《应用数学》 北大核心 2025年第1期211-216,共6页
In this paper we use Böcklund transformation to construct soliton solutions for a coupled KdV system.This system was first proposed by Wang in 2010.First we generalize the well-known Bäcklund transformation ... In this paper we use Böcklund transformation to construct soliton solutions for a coupled KdV system.This system was first proposed by Wang in 2010.First we generalize the well-known Bäcklund transformation for the KdV equation to such coupled KdV system.Then from a trivial seed solution,we construct soliton solutions.We also give a nonlinear superposition formula,which allows us to generate multi-soliton solutions. 展开更多
关键词 KdV equation Coupled KdV system b¨acklund transformation SOLITON
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Bcklund Transformation and Localized Coherent Structure for the (2+1)-Dimensional Asymmetric Nizhnik-Novikov-Veselov Equation 被引量:1
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作者 张解放 刘宇陆 《Journal of Shanghai University(English Edition)》 CAS 2002年第3期191-195,共5页
This article is concerned with the extended homogeneous balance method for studying the abundant localized solution structure of the (2+1) dimensional asymmetric Nizhnik Novikov Veselov equation. A B a¨... This article is concerned with the extended homogeneous balance method for studying the abundant localized solution structure of the (2+1) dimensional asymmetric Nizhnik Novikov Veselov equation. A B a¨ cklund transformation was first obtained, and then the richness of the localized coherent structures was found, which was caused by the entrance of two variable separated arbitrary functions, in the model. For some special choices of the arbitrary functions, it is shown that the localized structures of the model may be dromions, lumps, and ring solitons. 展开更多
关键词 homogeneous balance method coherent soliton structures asymmetric Nizhnik Novikov veselov equation (ANNV equation) b cklund transformation.
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Bcklund Transformation and Multisoliton Solutions in Terms of Wronskian Determinant for (2+1)-Dimensional Breaking Soliton Equations with Symbolic Computation 被引量:1
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作者 秦渤 田播 +2 位作者 刘立才 孟祥花 刘文军 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第12期1059-1066,共8页
In this paper, two types of the (2+1)-dimensional breaking soliton equations axe investigated, which describe the interactions of the Riemann waves with the long waves. With symbolic computation, the Hirota bilinea... In this paper, two types of the (2+1)-dimensional breaking soliton equations axe investigated, which describe the interactions of the Riemann waves with the long waves. With symbolic computation, the Hirota bilineax forms and Bgcklund transformations are derived for those two systems. Furthermore, multisoliton solutions in terms of the Wronskian determinant are constructed, which are verified through the direct substitution of the solutions into the bilineax equations. Via the Wronskian technique, it is proved that the Bgcklund transformations obtained are the ones between the ( N - 1)- and N-soliton solutions. Propagations and interactions of the kink-/bell-shaped solitons are presented. It is shown that the Riemann waves possess the solitonie properties, and maintain the amplitudes and velocities in the collisions only with some phase shifts. 展开更多
关键词 breaking soliton equations Hirota bilinear form b/icklund transformation Wronskian determinant symbolic computation
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In the Atmosphere and Oceanic Fluids:Scaling Transformations,Bilinear Forms,Bäcklund Transformations and Solitons for A Generalized Variable-Coefficient Korteweg-de Vries-Modified Korteweg-de Vries Equation
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作者 GAO Xin-yi GUO Yong-jiang +3 位作者 SHAN Wen-rui ZHOU Tian-yu WANG Meng YANGDan-yu 《China Ocean Engineering》 SCIE EI CSCD 2021年第4期518-530,共13页
The atmosphere is an evolutionary agent essential to the shaping of a planet,while in oceanic science and daily life,liquids are commonly seen.In this paper,we investigate a generalized variable-coefficient Korteweg-d... The atmosphere is an evolutionary agent essential to the shaping of a planet,while in oceanic science and daily life,liquids are commonly seen.In this paper,we investigate a generalized variable-coefficient Korteweg-de Vriesmodified Korteweg-de Vries equation for the atmosphere,oceanic fluids and plasmas.With symbolic computation,beginning with a presumption,we work out certain scaling transformations,bilinear forms through the binary Bell polynomials and our scaling transformations,N solitons(with N being a positive integer)via the aforementioned bilinear forms and bilinear auto-Bäcklund transformations through the Hirota method with some solitons.In addition,Painlevé-type auto-Bäcklund transformations with some solitons are symbolically computed out.Respective dependences and constraints on the variable/constant coefficients are discussed,while those coefficients correspond to the quadratic-nonlinear,cubic-nonlinear,dispersive,dissipative and line-damping effects in the atmosphere,oceanic fluids and plasmas. 展开更多
关键词 atmosphere oceanic fluids plasmas generalized variable-coefficient Korteweg-de Vries-modified Korteweg-de Vries equation scaling transformations bilinear forms N solitons auto-bäcklund transformations
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Generating Solutions to Discrete sine-Gordon Equation from Modified B(a|¨)cklund Transformation
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作者 寇鑫 张大军 +1 位作者 施英 赵松林 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第4期545-550,共6页
We modify the bilinear Biicklund transformation for the discrete sine-Gordon equation and derive variety of solutions by freely choosing parameters from the modified B^cklund transformation. Dynamics of solutions and ... We modify the bilinear Biicklund transformation for the discrete sine-Gordon equation and derive variety of solutions by freely choosing parameters from the modified B^cklund transformation. Dynamics of solutions and continuum limits are also discussed. 展开更多
关键词 discrete sine-Gordon equation b/icklund transformation limit solution semi-discrete sine-Gordon equation
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Bcklund transformations for the Burgers equation via localization of residual symmetries
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作者 刘希忠 俞军 +1 位作者 任博 杨建荣 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第11期125-128,共4页
We obtain the non-local residual symmetry related to truncated Painlev~ expansion of Burgers equation. In order to localize the residual symmetry, we introduce new variables to prolong the original Burgers equation in... We obtain the non-local residual symmetry related to truncated Painlev~ expansion of Burgers equation. In order to localize the residual symmetry, we introduce new variables to prolong the original Burgers equation into a new system. By using Lie's first theorem, we obtain the finite transformation for the localized residual symmetry. More importantly, we also Iocalize the linear superposition of multiple residual symmetries to find the corresponding finite transformations. It is interesting to find that the n-th B^icklund transformation for Burgers equation can be expressed by determinants in a compact way. 展开更多
关键词 burgers equation residual symmetry b^icklund transformation
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分数阶Riccati方程的Bäcklund变换及其应用
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作者 伊丽娜 扎其劳 套格图桑 《应用数学》 北大核心 2024年第4期1121-1132,共12页
基于整数阶辅助方程法的相关结论,给出了分数阶Riccati方程的包含广义双曲函数解和广义三角函数解的Mittag-Leffler函数新解、Bäcklund变换和解的非线性叠加公式.在此基础上,借助符号计算系统Mathematica,构造了分数阶KdV-mKdV方... 基于整数阶辅助方程法的相关结论,给出了分数阶Riccati方程的包含广义双曲函数解和广义三角函数解的Mittag-Leffler函数新解、Bäcklund变换和解的非线性叠加公式.在此基础上,借助符号计算系统Mathematica,构造了分数阶KdV-mKdV方程、分数阶(3+1)维Zakharov-Kuznetsov方程和分数阶Boussinesq方程的无穷序列新解. 展开更多
关键词 分数阶Riccati方程 Mittag-Leffler函数解 bäcklund变换 无穷序列新解
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Agrobacterium tumefaciens-mediated genetic transformation of the phytopathogenic fungus Penicillium digitatum 被引量:10
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作者 Ji-ye WANG Hong-ye LI 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2008年第10期823-828,共6页
Agrobacterium tumefaciens-mediated transformation (ATMT) system was assessed for conducting insertional mutagenesis in Penicillium digitatum, a major fungal pathogen infecting post-harvest citrus fruits. A transformat... Agrobacterium tumefaciens-mediated transformation (ATMT) system was assessed for conducting insertional mutagenesis in Penicillium digitatum, a major fungal pathogen infecting post-harvest citrus fruits. A transformation efficiency of up to 60 transformants per 106 conidia was achieved by this system. The integration of the hph gene into the fungal genome was verified by polymerase chain reaction (PCR) amplification and sequencing. These transformants tested were also shown to be mitotically stable. Southern blot analysis of 14 randomly selected transformants showed that the hph gene was randomly integrated as single copy into the fungal genome of P. digitatum. Thus, we conclude that ATMT of P. digitatum could be used as an alter-natively practical genetic tool for conducting insertional mutagenesis in P. digitatum to study functional genomics. 展开更多
关键词 Penicillium digitatum Agrobacterium tumefaciens-mediated transformation (ATMT) Hygromycin b resistance gene lnsertional mutagenesis
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Kinetic analysis of austenite transformation for B1500HS high-strength steel during continuous heating 被引量:2
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作者 Mu-yu Li Dan Yao +2 位作者 Liu Yang Hao-ran Wang Ying-ping Guan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2020年第11期1508-1516,共9页
The dilatometric curves of B1500HS high-strength steel at different heating rates were measured by a Gleeble-3800 thermal simulator and analyzed to investigate the effect of heating rate on austenitization.Results sho... The dilatometric curves of B1500HS high-strength steel at different heating rates were measured by a Gleeble-3800 thermal simulator and analyzed to investigate the effect of heating rate on austenitization.Results show that the value of starting temperature and ending temperature of austenite transformation increase with the rise of heating rates,whereas the temperature interval of austenite formation decreases.The kinetic equation of austenite transformation was solved using the Johnson–Mehl–Avrami model,and the related parameters of the equation were analyzed by the Kissinger method.For those calculations,the activation energy of austenite transformation is 1.01×10^6 J/mol,and the values of kinetic parameters n and ln k0 are 0.63 and 103.03,respectively.The relationship between the volume fraction of austenite and the heating time at different heating rates could be predicted using the kinetic equation.The predicted and experimental results were compared to verify the accuracy of the kinetic equation.The microstructure etched by different corrosive solutions was analyzed,and the reliability of kinetic equation was further verified from the microscopic perspective. 展开更多
关键词 b1500HS high-strength steel dilatometric curve austenite transformation kinetic equation Johnson-Mehl-Avuami model
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Genetic transformation of Pinus taeda by particle bombardment 被引量:1
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作者 唐巍 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第2期91-97,163,共7页
A protocol is presented for genetically engineering loblolly pine (Pinus taeda L.) using particle bombardment. This protocol enabled the routine transformation of loblolly pine plants that were previously difficult to... A protocol is presented for genetically engineering loblolly pine (Pinus taeda L.) using particle bombardment. This protocol enabled the routine transformation of loblolly pine plants that were previously difficult to transform. Mature zygotic embryos were used to be bombarded and to generate organogenic callus and transgenic regenerated plants. Plasmid pB48.215 DNA contained a synthetic Bacillus thuringiensis (B.t.) cryIAc coding sequence flanked by the double cauliflower mosaic virus (CaMV) 35S promoter and nopaline synthase (Nos) terminator sequences, and the selectable marker gene, neomycin phosphotransferase II (nptII) controlled by the promoter of the nopaline synthase gene was introduced into loblolly pine tissues by particle bombardment. The transformed tissues were proliferated and selected by kanamycin resistance conferred by the introduced NPTII gene. Shoot regeneration was induced from the kanamycin-resistant callus, and transgenic plantlets were then produced. The presence of the introduced genes in the transgenic loblolly pine plants was confirmed by polymerase chain reactions (PCR) analysis, by Southern blot analysis, and insect feeding assays. The recovered transgenic plants were acclimatized and then established in soil. 展开更多
关键词 Pinus taeda L. biolistic transformation bacillus thuringiensis (b.t.) cryIAb Insect feeding bioassay
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Genetic Transformation of Brassica campestris L.ssp.pekinensis via Agrobacterium-with Bt Gene 被引量:2
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作者 WangFeng LiHanxia +1 位作者 YeZhibiao LuYong'en 《Hunan Agricultural Science & Technology Newsletter》 2002年第4期10-14,共5页
By means of Agrobacterium-mediated transformation, 43 kanamycin-resistant buds of Chinese cabbage were got. PCR, PCR-Southern blot and dot blot analysis were used to identify and characterize the putative transgenic p... By means of Agrobacterium-mediated transformation, 43 kanamycin-resistant buds of Chinese cabbage were got. PCR, PCR-Southern blot and dot blot analysis were used to identify and characterize the putative transgenic plants. 26 plants had the predicted bands of the fragment of npt Ⅱ gene. Insect bioassays of 4 transformants showed that toxic protein had been translated and the translation levels were different among these transformants. 展开更多
关键词 Chinese cabbage bt gene genetic transformation cry IA(b)
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Genetic transformation of cry1A(b) gene into teak 被引量:1
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作者 Norwati A. Abdullah R. +1 位作者 Mohd Rosli H. and Norlia B. 《分子植物育种》 CAS CSCD 2003年第1期53-57,共5页
Teak (Tectona grandis) provides one of the most highly sought after timber in the world and is a widely recommended species for reforestation. As such teak is widely planted in Malaysia. Though no serious outbreaks ha... Teak (Tectona grandis) provides one of the most highly sought after timber in the world and is a widely recommended species for reforestation. As such teak is widely planted in Malaysia. Though no serious outbreaks have been recorded for teak in Malaysia, but insect attack remains the most important threat to the timber industry. Thus, in efforts to overcome the problem, an integrated pest management system needs to be developed. Spraying of commercial Bt has been a common practice in addressing minor outbreaks. However, one of the main limitations of the spraying technique is poor coverage, especially on plant surfaces. Poor coverage, however, could be overcome by planting insect resistant trees. In addition, the approach of using genetic engineering in addressing the above problem proves to be possible with the advancement made in genetic transformation of trees especially in the last decade. This, together with improved knowledge on gene function following improved DNA recombinant techniques promises the major advancement in pest management of forest species. This report demonstrates the possibility of transferring foreign gene into teak cells. In this study, nodal segments of teak were subjected to particle bombardment. Nodal segments bombarded with gold particles coated with plasmid DNA carrying hygromycin phosphotransferase (hpt), β glucuronidase (gus) and cry1A(b) genes were then transferred onto medium for shoot development. The shoots were than transferred onto the same medium supplemented with 10mg/L hygromycin for selection. Selection was repeated several times with six week subculture intervals on the same Hm containing media. The presence of the transgenes in the Hmr plants was confirmed using PCR. 展开更多
关键词 柚木 基因转化 crylA(b)基因 害虫综合治理 基因重组 PCR 潮霉素
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Sine Transformation and the Reparametrization of Bézier Curves 被引量:1
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作者 LIANG Xi-kun TAO Li-min 《Computer Aided Drafting,Design and Manufacturing》 2007年第2期23-27,共5页
A solution to the reparametrization of Bézier curves by sine transformation of Bemstein basis is presented. The new effective reparametrization method is given through the following procedures: educing Sine Bems... A solution to the reparametrization of Bézier curves by sine transformation of Bemstein basis is presented. The new effective reparametrization method is given through the following procedures: educing Sine Bemstein-Bézier Class-SBBC function, defining SBBC curve and discussing the relation between SBBC and Bézier curve. 展开更多
关键词 sine transformation SbbC functions SbbC curves bézier curve repararnetrization
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Establishment of Agrobacterium tumefaciens-mediated Genetic Transformation System for Aspergillus awamori
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作者 Feng CHEN Kun WANG +3 位作者 Chao YIN Deming LI Nan REN Junxing LI 《Agricultural Biotechnology》 CAS 2012年第3期44-48,51,共6页
[ Objective ] This study aimed to establish Agrobacterium tumefaciens-mediated genetic transformation system for Aspergillus awamori and investigate the feasibility of expressing heterologous proteins in A. awamori. [... [ Objective ] This study aimed to establish Agrobacterium tumefaciens-mediated genetic transformation system for Aspergillus awamori and investigate the feasibility of expressing heterologous proteins in A. awamori. [ Method] Appropriate A. awamori host strains were determined according to the secretory protein profile. Selectable marker was selected for genetic transformation by drug sensitivity analysis. The established A. awamori genetic transformation system was used for transformation and expression analysis of Rhizomucor miehei lipase (RML). The feasibility of using A. awamori to express heterologous proteins was investigated by identification of transformants and property analysis. [ Result~ Based on the analysis of secretory protein profile, A. awamori strains CBS115.52 and CICC2257 were determined as the host strains for heterologous protein expression ; drug sensitivity analysis shows that hygromycin B resistance gene ( HygBr ) is an effective ge- netic seleetable marker; by using Agrobacterium tumefaciens-mediatcd transformation (ATMT) method, the plasmid pHGW-amdS containing HygBr was successfully transformed into A. awamori strain CBS115.52 to establish the genetic transformation system ofA. awamorl with HygBr as selectable marker. RML was transformed into A. awamori and its expression was validated by substrate hydrolysis test, SDS-PAGE and Western blot. [ Conclusion] This study demonstrates that the genetic transformation system of A. awamori mediated by Agrobacterium tumefaciens has potential feasibility for expression of heterologous proteins. 展开更多
关键词 Aspergillus awamoH Agrobacterium tumefaciens-mediated transformation (ATMT) Hygromycin b resistant gene (Hygbr) Rhizomucor miehei lipase (RML)
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Microstructure and Stability of Fe_(73.5) Cu_1Nb_3Si_(13.5)B_9 Alloy at Different Stages of Phase Transformation
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作者 Guiyi ZENG, Qixian BA and Hualin ZENG (Northeastern University, Shenyang 110006, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第2期153-154,共2页
The microstructure and the stability of Fe_73.5Cu_1Nb_3Si_13.5B_9 alloy at different stages of phase transformation were investigated through the observation of X-ray difraction and transmission electron microscopy an... The microstructure and the stability of Fe_73.5Cu_1Nb_3Si_13.5B_9 alloy at different stages of phase transformation were investigated through the observation of X-ray difraction and transmission electron microscopy and the measurement of magnetic aftereffect (MAE). It was found that the dependence of the volume fraction of amorphous phase and the MAE in the samples annealed from 450 to 700℃ on the annealing temperature is similar. 展开更多
关键词 b9 Alloy at Different Stages of Phase transformation Microstructure and Stability of Fe Cu1Nb3Si SI
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Luteolin affects the EMT transformation and cell biological behavior of osteosarcoma U2OS cells via the PI3K/AKT/NF-κB signaling pathway
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作者 Guo-Xin Qu Zhi-Hua Ji +2 位作者 Kun Fu Hua-Yi Qu Yue-Song Wu 《Journal of Hainan Medical University》 2019年第21期1-6,共6页
Objective:To investigate the effect of luteolin on the Epithelial-mesenchymal transition(EMT)of osteosarcoma cell line U2OS and its molecular mechanism by regulating phosphoinositide 3-kinase/protein kinase B/nuclear ... Objective:To investigate the effect of luteolin on the Epithelial-mesenchymal transition(EMT)of osteosarcoma cell line U2OS and its molecular mechanism by regulating phosphoinositide 3-kinase/protein kinase B/nuclear factor-kappa B(PI3K/AKT/NF-κB)signaling pathway.Methods:U2OS cells were treated in different concentrations(10,20 and 40μmol/L)of luteolin.MTT was used to detect the effect of luteolin on the proliferation of osteosarcoma U2OS cells.Transwell chamber assay was used to detect the influence of luteolin on migration of U2OS cells.qPCR was used to detect the influence of luteolin on the mRNA expression of Bax,Bcl-2 and Caspase-2 in U2OS cells.Western blot was used to observe the change of p-PI3K,p-AKT,p-IKK and NF-κB proteins.Immunofluorescence was used to detect the influence of luteolin on the protein expression of E-cadherin and vimentim.Results:Luteolin inhibited significantly the proliferation of U2OS cells(P<0.05)in a time-concentration-dependent manner.Luteolin inhibited significantly the migration of U2OS cells(P<0.05).After treatment with luteolin,the mRNA expression of Bax and Caspase-2 was increased significantly(P<0.05),but Bcl-2 was reduced significantly(P<0.05)in U2OS cells.The protein expression of p-PI3K,p-AKT,p-IKK,NF-κB,E-cadherin and vimentin was decreased significantly(P<0.05).Conclusions:Luteolin inhibits the proliferation,migration and EMT transformation of osteosarcoma U2OS cells,which may be related to the inhibition of PI3K/AKT/NF-κB signaling pathway. 展开更多
关键词 LUTEOLIN PI3K/AKT/NF-κb signaling pathway OSTEOSARCOMA EMT transformation CELL biological behavior
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载脂蛋白A1、载脂蛋白B水平与急性脑梗死患者静脉溶栓后出血转化的相关性分析
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作者 张静 张琴 《临床医学研究与实践》 2025年第2期33-36,共4页
目的分析载脂蛋白A(ApoA1)、载脂蛋白B(ApoB)水平与急性脑梗死(ACI)患者静脉溶栓后出血转化(HT)的相关性。方法选择2020年2月至2022年12月于本院接受静脉溶栓治疗的206例ACI患者为研究对象,依据溶栓后14 d内是否发生HT将其分为非HT组和H... 目的分析载脂蛋白A(ApoA1)、载脂蛋白B(ApoB)水平与急性脑梗死(ACI)患者静脉溶栓后出血转化(HT)的相关性。方法选择2020年2月至2022年12月于本院接受静脉溶栓治疗的206例ACI患者为研究对象,依据溶栓后14 d内是否发生HT将其分为非HT组和HT组。比较两组的一般资料及溶栓前血清ApoA1、ApoB水平;分析ACI患者静脉溶栓后发生HT的影响因素;分析血清ApoA1、ApoB对HT的预测价值。结果206例ACI患者静脉溶栓治疗后的HT发生率约为18.93%。HT组的高血压、糖尿病占比及入院时美国国立卫生研究院卒中量表(NIHSS)评分、脑梗死体积、血清ApoB水平均明显高于非HT组,血清ApoA1水平明显低于非HT组(P<0.05)。Logistic回归分析结果显示,高血压、入院时NIHSS评分、脑梗死体积、血清ApoB水平均是影响ACI患者静脉溶栓后发生HT的危险因素,而血清ApoA1水平是保护因素(P<0.05)。受试者工作特征(ROC)曲线分析结果显示,血清ApoA1、ApoB水平预测ACI静脉溶栓后发生HT的曲线下面积(AUC)分别为0.865、0.769。结论ACI患者血清ApoA1和ApoB均与溶栓后HT的发生密切相关,对HT的发生具有一定的预测价值。 展开更多
关键词 急性脑梗死 静脉溶栓 出血转化 载脂蛋白A1 载脂蛋白b
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非线性弦振动方程的Painlevé性质、Bcklund变换和孤子解的聚变(英文) 被引量:8
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作者 徐淑奖 姜璐 郭玉翠 《计算物理》 CSCD 北大核心 2010年第2期309-316,共8页
借助于计算机符号计算系统Maple,用Weiss,Tabor和Carnevale等人提出的WTC方法首次验证非线性弦振动方程具有Painlevé性质,并得到非线性弦振动方程的Bcklund变换,用Hirota直接方法分析非线性弦振动方程孤子解的聚变现象.
关键词 PAINLEVÉ分析 bcklund变换 孤子聚变 非线性弦振动方程
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Benjamin方程的Bcklund变换、非线性叠加公式及无穷守恒律 被引量:6
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作者 张鸿庆 张玉峰 《应用数学和力学》 CSCD 北大核心 2001年第10期1017-1021,共5页
利用屠格式求出了Benjamin方程的B cklund变换、精确孤波解。
关键词 bENJAMIN方程 无穷守恒律 非线性波动方程 bAEcklund变换 非线性 叠加公式
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基于Ramberg-Bcklund反应的白藜芦醇合成 被引量:2
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作者 王辉 周海珠 +2 位作者 王三永 李春荣 张永红 《精细化工》 EI CAS CSCD 北大核心 2011年第5期492-496,共5页
以3,5-二甲氧基苯甲醛、对甲氧基苄醇为原料,经合成硫醚和砜的中间产物,再利用Ramberg-Backlund反应将砜转化为反式碳碳双键,最后脱去甲基获得白藜芦醇。研究探讨了反应条件对硫醚氧化和对Ramberg-Backlund反应的影响。结果表明,在以H2O... 以3,5-二甲氧基苯甲醛、对甲氧基苄醇为原料,经合成硫醚和砜的中间产物,再利用Ramberg-Backlund反应将砜转化为反式碳碳双键,最后脱去甲基获得白藜芦醇。研究探讨了反应条件对硫醚氧化和对Ramberg-Backlund反应的影响。结果表明,在以H2O2-SeO2为氧化剂,CH3OH为溶剂的条件下,硫醚的氧化效果最佳,砜的产率可达82%;在以CCl4-KOH作为卤化试剂,V(正丁醇)∶V(水)=6∶1的正丁醇-水作为溶剂的条件下,Ramberg-Backlund反应的效果最好,反式双键产物的产率为84%。该合成路线总产率为41%。产物及各中间体的结构经1H(13C)NMR、IR和ESI-MS确证。 展开更多
关键词 Ramberg-backlund反应 白藜芦醇 医药与日化原料
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