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Rho激酶抑制剂对大鼠脑缺血损伤的脑保护作用及S100B蛋白表达的影响 被引量:4
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作者 刘康 丁素菊 +2 位作者 吴涛 仇一青 郭鹏 《临床神经病学杂志》 CAS 北大核心 2011年第2期111-113,共3页
目的探讨Rho激酶抑制剂(法舒地尔)对大鼠脑缺血损伤的脑保护作用及S100B蛋白表达的影响。方法 90只雄性SD大鼠随机分为假手术组、脑缺血组和法舒地尔组。采用大脑中动脉线栓法制作大鼠局灶性脑缺血模型。术后对3组大鼠进行神经功能缺... 目的探讨Rho激酶抑制剂(法舒地尔)对大鼠脑缺血损伤的脑保护作用及S100B蛋白表达的影响。方法 90只雄性SD大鼠随机分为假手术组、脑缺血组和法舒地尔组。采用大脑中动脉线栓法制作大鼠局灶性脑缺血模型。术后对3组大鼠进行神经功能缺损评分(NSS);用分光光度法测定髓过氧化物酶(MPO)活性;用干湿重法测定脑含水量;伊文思蓝(EB)法测定血-脑屏障的通透性;实时荧光定量逆转录PCR法检测缺血脑组织中S100B蛋白的表达。结果与假手术组比较,脑缺血组和法舒地尔组大鼠NSS和MPO活性明显增高,脑含水量、EB含量及S100B蛋白表达明显增加(P〈0.05~0.01)。与脑缺血组比较,法舒地尔组大鼠NSS和MPO活性明显降低,脑含水量、EB含量及S100B蛋白表达明显减少(均P〈0.05)。结论法舒地尔可通过抑制脑缺血损伤后的炎症反应发挥脑保护作用,其机制可能与下调S100B蛋白的表达有关。 展开更多
关键词 rho激酶抑制剂 脑缺血损伤 s100B蛋白 炎症
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Advantages of Rho-associated kinases and their inhibitor fasudil for the treatment of neurodegenerative diseases 被引量:7
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作者 Qing Wang Li-Juan Song +4 位作者 Zhi-Bin Ding Zhi Chai Jie-Zhong Yu Bao-Guo Xiao Cun-Gen Ma 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第12期2623-2631,共9页
Ras homolog(Rho)-associated kinases(ROCKs)belong to the serine-threonine kinase family,which plays a pivotal role in regulating the damage,survival,axon guidance,and regeneration of neurons.ROCKs are also involved in ... Ras homolog(Rho)-associated kinases(ROCKs)belong to the serine-threonine kinase family,which plays a pivotal role in regulating the damage,survival,axon guidance,and regeneration of neurons.ROCKs are also involved in the biological effects of immune cells and glial cells,as well as the development of neurodegenerative disorders such as Alzheimer’s disease,Parkinson’s disease,and multiple sclerosis.Previous studies by us and others confirmed that ROCKs inhibitors attenuated the symptoms and progression of experimental models of the abovementioned neurodegenerative diseases by inhibiting neuroinflammation,regulating immune imbalance,repairing the blood-brain barrier,and promoting nerve repair and myelin regeneration.Fasudil,the first ROCKs inhibitor to be used clinically,has a good therapeutic effect on neurodegenerative diseases.Fasudil increases the activity of neural stem cells and mesenchymal stem cells,thus optimizing cell therapy.This review will systematically describe,for the first time,the effects of abnormal activation of ROCKs on T cells,B cells,microglia,astrocytes,oligodendrocytes,and pericytes in neurodegenerative diseases of the central nervous system,summarize the therapeutic potential of fasudil in several experimental models of neurodegenerative diseases,and clarify the possible cellular and molecular mechanisms of ROCKs inhibition.This review also proposes that fasudil is a novel potential treatment,especially in combination with cell-based therapy.Findings from this review add support for further investigation of ROCKs and its inhibitor fasudil for the treatment of neurodegenerative diseases. 展开更多
关键词 Alzheimer’s disease cell-based therapy central nervous system cells FAsUDIL IMMUNOCYTEs multiple sclerosis Parkinson’s disease PERICYTEs rho kinase inhibitor rho-associated kinases
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Blind Deconvolution of Seismic Data Based on the Spearman’s Rho
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作者 Rongrong Wang Fei Xu Xiaobo Zhou 《Journal of Computer and Communications》 2015年第3期20-26,共7页
In this paper, we propose a novel seismic blind deconvolution approach based on the Spearman’s rho in the case of band-limited seismic data with a low dominant frequency and short data records. The Spearman’s rho is... In this paper, we propose a novel seismic blind deconvolution approach based on the Spearman’s rho in the case of band-limited seismic data with a low dominant frequency and short data records. The Spearman’s rho is a measure of the dependence between two continuous random variables without the influence of the marginal distributions, by which a new criterion for blind deconvolution is constructed. The optimization program for new criterion of blind deconvolution is performed by applying Neidell’s wavelet model to the inverse filter. The noise-free and noisy synthetic data, onshore seismic trace in the Ordos Basin, and offshore stacked section in the Bohai Bay Basin examples show good results of the method. 展开更多
关键词 spearman’s rho Mutual Information Neidell’s WAVELET sEIsMIC BLIND DECONVOLUTION Inverse Filter
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A holographic optical communication system based on RSA algorithm and quaternion function
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作者 YANG Peng HAN Jianning 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第3期338-343,共6页
A facile encryption way was successfully applied to the holographic optical encryption system with high speed,multidimensionality,and high capacity,which provided a better security solution for underwater communicatio... A facile encryption way was successfully applied to the holographic optical encryption system with high speed,multidimensionality,and high capacity,which provided a better security solution for underwater communication.The reconstructed optical security system for information transmission was based on wavelengthλand focal length f that were keys to encryption and decryption.To finish the secure data transmission(λ,f)between sender and receiver,an extended Rivest-Shamir-Adleman(ERSA)algorithm for the encryption was achieved based on three-dimension quaternion function.Therein,the Pollard’s rho method was used for the evaluation and comparison of RSA and ERSA algorithms.The results demonstrate that the message encrypted by the ERSA algorithm has better security than that by RSA algorithm in the face of unpredictability and complexity of information transmission on the unsecure acoustic channel. 展开更多
关键词 HOLOGRAPHY QUATERNION Fourier lens extended Rivest-shamir-Adleman(ERsA) Pollard’s rho method
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Modeling dependence based on mixture copulas and its application in risk management 被引量:2
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作者 OUYANG Zi-sheng LIAO Hui YANG Xiang-qun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第4期393-401,共9页
This paper is concerned with the statistical modeling of the dependence structure of multivariate financial data using the copula, and the application of copula functions in VaR valuation. After the introduction of th... This paper is concerned with the statistical modeling of the dependence structure of multivariate financial data using the copula, and the application of copula functions in VaR valuation. After the introduction of the pure copula method and the maximum and minimum mixture copula method, authors present a new algorithm based on the more generalized mixture copula functions and the dependence measure, and apply the method to the portfolio of Shanghai stock composite index and Shenzhen stock component index. Comparing with the results from various methods, one can find that the mixture copula method is better than the pure Gaussian copula method and the maximum and minimum mixture copula method on different VaR level. 展开更多
关键词 Gaussian mixture copula VALUE-AT-RIsK DEPENDENCE back-test spearman's rho
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The Bivariate Normal Integral via Owen’s T Function as a Modified Euler’s Arctangent Series
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作者 Janez Komelj 《American Journal of Computational Mathematics》 2023年第4期476-504,共29页
The Owen’s T function is presented in four new ways, one of them as a series similar to the Euler’s arctangent series divided by 2&#960, which is its majorant series. All possibilities enable numerically stable ... The Owen’s T function is presented in four new ways, one of them as a series similar to the Euler’s arctangent series divided by 2&#960, which is its majorant series. All possibilities enable numerically stable and fast convergent computation of the bivariate normal integral with simple recursion. When tested  computation on a random sample of one million parameter triplets with uniformly distributed components and using double precision arithmetic, the maximum absolute error was 3.45 × 10<sup>-</sup><sup>16</sup>. In additional testing, focusing on cases with correlation coefficients close to one in absolute value, when the computation may be very sensitive to small rounding errors, the accuracy was retained. In rare potentially critical cases, a simple adjustment to the computation procedure was performed—one potentially critical computation was replaced with two equivalent non-critical ones. All new series are suitable for vector and high-precision computation, assuming they are supplemented with appropriate efficient and accurate computation of the arctangent and standard normal cumulative distribution functions. They are implemented by the R package Phi2rho, available on CRAN. Its functions allow vector arguments and are ready to work with the Rmpfr package, which enables the use of arbitrary precision instead of double precision numbers. A special test with up to 1024-bit precision computation is also presented. 展开更多
关键词 Owen’s T Function Bivariate Normal Integral Euler’s Arctangent series RECURsION R Package Phi2rho
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碳达峰国家达峰特征与启示 被引量:24
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作者 张楠 张保留 +3 位作者 吕连宏 白梓函 赵明轩 罗宏 《中国环境科学》 EI CAS CSCD 北大核心 2022年第4期1912-1921,共10页
基于世界银行数据库1960~2020年数据,采用Mann-Kendall(MK)检验和Spearman's Rho(SR)检验,对全球219个国家及地区的CO_(2)排放及社会经济数据进行趋势分析.结果表明:MK检验和SR检验得出一致结论,共有42个国家和1个经济体联盟实现碳... 基于世界银行数据库1960~2020年数据,采用Mann-Kendall(MK)检验和Spearman's Rho(SR)检验,对全球219个国家及地区的CO_(2)排放及社会经济数据进行趋势分析.结果表明:MK检验和SR检验得出一致结论,共有42个国家和1个经济体联盟实现碳达峰,46个国家处于碳达峰平台期.多数国家碳达峰时具备以下特征:人均GDP达2×10^(4)~5×10^(4)美元,第三产业占比高于50%,化石能源消耗占比仍高于60%,且碳排放处于环境库兹涅茨曲线的下降阶段,经济发展与碳排放脱钩.借鉴已达峰国家的经验,中国应进一步调整能源结构,提高可再生能源消费占比;优化产业结构,加快构建以服务业为主导的国民经济新格局;制定区域差异化碳达峰目标,推动有条件的地区率先达峰. 展开更多
关键词 碳排放峰值 达峰特征 MANN-KENDALL检验 spearman's rho检验 环境库兹涅茨曲线
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铁路路基沉降变形趋势的综合检验分析 被引量:13
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作者 鞠兴华 杨晓华 张莎莎 《中国安全科学学报》 CAS CSCD 北大核心 2018年第3期132-137,共6页
为综合掌握路基沉降的变形过程,基于路基沉降的现场监测数据,提出下述方案:应用重标方差(V/S)分析、曼-肯德尔(M-K)检验和斯皮尔曼秩相关系数(SR)3种方法检验判断路基的整体变形和阶段性变形趋势。研究结果表明:在整体变形趋势... 为综合掌握路基沉降的变形过程,基于路基沉降的现场监测数据,提出下述方案:应用重标方差(V/S)分析、曼-肯德尔(M-K)检验和斯皮尔曼秩相关系数(SR)3种方法检验判断路基的整体变形和阶段性变形趋势。研究结果表明:在整体变形趋势的判断中,用这3种方法均得出路基沉降变形呈增长趋势,具有较好的一致性;在阶段性变形趋势的判断中,各阶段变形趋势存在差异,但也均呈持续增长趋势,与整体变形趋势结果相同,进一步验证了3种方法的可靠性和适用性。 展开更多
关键词 铁路路基 重标方差(V/s)分析 曼-肯德尔(M-K)检验 斯皮尔曼秩相关系数(sR)检验 变形趋势判断
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基于Rock2信号通路探讨黄芩苷对阿尔茨海默病小鼠学习记忆功能的影响 被引量:3
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作者 黄燕 骆飞飞 +2 位作者 唐卉 周嫱 徐朝义 《中西医结合心脑血管病杂志》 2022年第20期3709-3716,共8页
目的构建阿尔茨海默病模型淀粉样前体蛋白(APP)及早老素-1(PS1)双转基因小鼠,观察黄芩苷对小鼠学习记忆功能改善的影响。方法体内实验将APP/PS1转基因小鼠分为模型组与黄芩苷组,同时将野生型小鼠作为对照组。黄芩苷组连续灌胃给药28 d,... 目的构建阿尔茨海默病模型淀粉样前体蛋白(APP)及早老素-1(PS1)双转基因小鼠,观察黄芩苷对小鼠学习记忆功能改善的影响。方法体内实验将APP/PS1转基因小鼠分为模型组与黄芩苷组,同时将野生型小鼠作为对照组。黄芩苷组连续灌胃给药28 d,剂量60 mg/kg,其他两组灌胃等体积生理盐水。之后进行为期6 d的水迷宫实验。麻醉小鼠检测海马区兴奋性突触后电位。结束后处死小鼠,分离脑组织进行免疫组化染色,蛋白免疫印迹法(Western Blot)检测相关蛋白。体外实验应用PC12细胞,首先检测不同剂量β-淀粉样蛋白(Aβ)_(25-35)对PC12细胞存活率的影响,再检测黄芩苷对Aβ_(25-35)干预PC12细胞存活率的改善作用。将PC12细胞分为对照组、模型组、黄芩苷组与黄芩苷+溶血磷脂酸组。采用免疫荧光检测Rock2表达,Western Blot检测Caspase-3等凋亡相关蛋白表达。结果体内实验中,与模型组比较,经黄芩苷治疗的APP/PS1小鼠逃避潜伏期降低(P<0.05),穿越平台次数与靶象限停留时间增加(P<0.05)。黄芩苷可提高小鼠长时程电位(P<0.05),减少海马组织Aβ蛋白沉积(P<0.05)。Western Blot检测结果显示,黄芩苷减少了海马组织Rock2蛋白与Cleaved-Caspase-3蛋白表达(P<0.05),提高了Bcl-2/Bax比例(P<0.05)。体外实验中,200μmol/L黄芩苷显著提高了30μmol/L Aβ_(25-35)干预的PC12细胞存活率(P<0.05),抑制了Rho激酶(Rock2)蛋白与Cleaved-Caspase-3蛋白表达,提高Bcl-2/Bax比例(P<0.05)。溶血磷脂酸干预逆转了黄芩苷的作用,提高了Rock蛋白与Cleaved-Caspase-3蛋白表达,降低了Bcl-2/Bax比例。结论黄芩苷可治疗阿尔茨海默病,其机制是下调Rock2蛋白表达水平,减少Aβ沉积,减少细胞凋亡,提高长时程电位,改善小鼠学习与记忆功能障碍。 展开更多
关键词 阿尔茨海默病 黄芩苷 rho激酶 β-淀粉样蛋白 学习记忆功能 小鼠 实验研究
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相关系数在脉冲噪声环境下的稳健性综述 被引量:1
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作者 徐维超 马如豹 《广东工业大学学报》 CAS 2015年第3期1-4,共4页
作为相关分析的重要工具,相关系数在众多科学与技术领域中都得到了广泛的研究和应用.基于文献中两种常用的二元混合高斯模型,本文回顾和对比了5种相关系数分别在单通道以及双通道中存在脉冲噪声时的稳健性.定量的研究结果表明,在脉冲噪... 作为相关分析的重要工具,相关系数在众多科学与技术领域中都得到了广泛的研究和应用.基于文献中两种常用的二元混合高斯模型,本文回顾和对比了5种相关系数分别在单通道以及双通道中存在脉冲噪声时的稳健性.定量的研究结果表明,在脉冲噪声环境下,文献中最为常见的皮尔逊积矩相关系数性能急剧恶化.而另外4种相关系数则在两种噪声模型下均表现出良好的抗干扰能力. 展开更多
关键词 皮尔逊积距相关系数 斯皮尔曼秩次相关系数 肯德尔秩次相关系数 基尼相关 皮尔逊秩变量相关系数 脉冲噪声 混合高斯模型
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关于区间上离散对数问题的改进算法 被引量:3
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作者 王瑶 吕克伟 《密码学报》 CSCD 2015年第6期570-582,共13页
在群G上区间大小为N的离散对数问题为:给定g,h∈G以及大整数N,找到整数n(0≤n≤N),使得h=g^n,人们对于该问题的求解主要是对Pollard's kangaroos method的改进,尝试通过减少跳跃次数来优化算法,目前解决这一问题的最优低存储算法是V... 在群G上区间大小为N的离散对数问题为:给定g,h∈G以及大整数N,找到整数n(0≤n≤N),使得h=g^n,人们对于该问题的求解主要是对Pollard's kangaroos method的改进,尝试通过减少跳跃次数来优化算法,目前解决这一问题的最优低存储算法是Van Oorschot和Wiener版本的Pollard's kangaroos method,其平均情况下的时间代价是(2+0(1))√N次群运算.文中对解决这一问题的经典Pollard's kangaroos method进行改进得到新的求解算法.新算法是通过利用多次小整数乘法代替一次完整的大整数乘法来减少kangaroos每次跳跃的时间代价实现算法效率的提高.进一步,文中通过增加kangaroos的数量使得算法在跳跃次数和每次跳跃的时间代价两方面都得到改进,从而得到区间上离散对数问题的更有效的求解算法. 展开更多
关键词 离散对数(DLP) Pollard’s KANGAROOs METHOD Pollard’s rho METHOD 区间 时间代价
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Solving the Multi-discrete Logarithm Problems over a Group of Elliptic Curves with Prime Order
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作者 Jun Quan LI Mu Lan LIU Liang Liang XIAO 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2005年第6期1443-1450,共8页
In this paper, we discuss the expected number of steps in solving multi-discrete logarithm problems over a group of elliptic curves with prime order by using Pollard's rho method and parallel collision search algorit... In this paper, we discuss the expected number of steps in solving multi-discrete logarithm problems over a group of elliptic curves with prime order by using Pollard's rho method and parallel collision search algorithm. We prove that when using these algorithms to compute discrete logarithms, the knowledge gained through computing many logarithms does not make it easier for finding other logarithms. Hence in an elliptic cryptosystem, it is safe for many users to share the same curve, with different private keys. 展开更多
关键词 Pollard's rho method Parallel collision search algorithm Elliptic curve Discrete logarithm Distinguished point
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基于线性视觉模拟标尺的评审方法在科研课题立项评审中的应用及其对照分析 被引量:2
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作者 梁公文 王丹蕾 +6 位作者 张华 徐涛 李佳 荆珊 王兵 李媛 刘玉兰 《中华医学科研管理杂志》 2008年第6期343-344,367,共3页
北京大学人民医院对医院研究与发展基金实施全过程管理,从课题申报、立项评审、中期评估、结题都有严格的管理规定。为了保证科研课题立项评审的公正、公平,北京大学人民医院建立了基于线性视觉模拟标尺评分方法的评审方法,并应用于... 北京大学人民医院对医院研究与发展基金实施全过程管理,从课题申报、立项评审、中期评估、结题都有严格的管理规定。为了保证科研课题立项评审的公正、公平,北京大学人民医院建立了基于线性视觉模拟标尺评分方法的评审方法,并应用于医院研究与发展基金的课题立项评审。从评审结果的对照分析表明,基于线性视觉模拟标尺的评审方法具有与传统的Likert相同的评审可信度,可应用于课题立项评审;与传统的Likert量表评审方法相比,基于线性视觉模拟标尺的评审方法的评审区分度更好。 展开更多
关键词 课题评审 线性视觉模拟标尺 斯皮尔曼等级相关系数
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