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基于小波变换和分形表达的绞股蓝药材质量评价方法研究

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中成药 2008年第10期30卷 1494-1498页

作者：刘芳胡坪 Annika Küster 任德权华东理工大学化学与分子工程学院上海200237 华东理工大学药学院上海200237 吕贝克应用技术大学

目的:建立绞股蓝药材的HPLC指纹图谱,采用分形理论与小波变换的方法进行指纹图谱的特征提取,利用相似度计算对绞股蓝药材进行质量评价。方法:用甲醇回流提取绞股蓝药材中的黄酮类成分,建立HPLC指纹图谱。将色谱响应信号进行小波分解,并... 详细信息

目的:建立绞股蓝药材的HPLC指纹图谱,采用分形理论与小波变换的方法进行指纹图谱的特征提取,利用相似度计算对绞股蓝药材进行质量评价。方法:用甲醇回流提取绞股蓝药材中的黄酮类成分,建立HPLC指纹图谱。将色谱响应信号进行小波分解,并用分形维数描述各小波基参量。以小波基分形参量为特征变量,对不同产地的绞股蓝药材进行相似度比较。结果:采用优化的提取与分析条件建立了绞股蓝药材的指纹图谱。各样品相对于参照品的相似度可有效的评价各种绞股蓝样品。结论:以小波基分形参量表达的色谱指纹图谱用于中药材的质量评价,相对于人工选择特征峰更具客观性。以小波基分形参量计算的相似度可以定性评价绞股蓝样品;浙江产绞股蓝药材可以作为陕西安康绞股蓝的替代药材。

关键词：绞股蓝分形维数小波变换相似度指纹图谱

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夏季极区中层顶大气浑沌性的VHF雷达观测

科学通报 1996年第6期41卷 521-523页

作者：熊建刚易帆 J.Klostermeyer R.Rüster 中国科学院武汉物理研究所武汉430071 Max-Planck-Institut für Aeronomie Germany

随着探测技术的不断完善,大量观测资料揭示了真实大气的复杂运动过程,然而与通过对大气动力学系统作数值分析研究大气浑沌性相比,我们对真实大气运动的复杂性的了解还是初步的。对于像大气运动这样的耗散系统,它的浑沌性通常用3个统计... 详细信息

随着探测技术的不断完善,大量观测资料揭示了真实大气的复杂运动过程,然而与通过对大气动力学系统作数值分析研究大气浑沌性相比,我们对真实大气运动的复杂性的了解还是初步的。对于像大气运动这样的耗散系统,它的浑沌性通常用3个统计特征量来描写,即维数、Lyapunov指数和熵。最近10多年来,用这些特征量刻划大气运动结构的工作在国内外发展很快,郑祖光和刘式达讨论了近地面大气的浑沌状态;Fra.drich等发现低层大气浑沌吸引子的维数与季节有关;Yang等用MU雷达观测资料计算了平流层大气运动的维数和熵。但有关更高层大气运动浑沌特性的工作尚未见文献报道。

关键词： VHF雷达中层顶大气浑沌性大气探测平流层

应用人工合成的HIV nef蛋白肽制备抗nef单抗

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免疫学杂志 1990年第3期6卷 153-157页

作者：史良如 J.Enzman M.Schneider H.Brüster *** 卫生部武汉生物制品研究所免疫学研究室武汉430031 Institute for transfusion Medicine Uni ClinicDüsseldorfFRG

本文用人工合成的HIV nef蛋白肽免疫Belb/c小鼠,应用活体融合法制备了11个抗nef单克隆抗体。ELISA测定表明,11个单抗均能与nef肽和nef蛋白反应,其中3、7、9、10和11号抗体与nef肽和nef蛋白的反应性相近似;4、5、6和7号抗体与nef蛋白的... 详细信息

本文用人工合成的HIV nef蛋白肽免疫Belb/c小鼠,应用活体融合法制备了11个抗nef单克隆抗体。ELISA测定表明,11个单抗均能与nef肽和nef蛋白反应,其中3、7、9、10和11号抗体与nef肽和nef蛋白的反应性相近似;4、5、6和7号抗体与nef蛋白的反应性明显比肽强。所有单抗均不与HIV的其它蛋白反应。应用免疫荧光检测抗nef单抗与HIV感染细胞的反应性表明,大部分抗体均与细胞浆着色,而无一般膜荧光的典型征象。

关键词： HIV a.dS nef肽单克隆抗体

Mixed convection of alumina-water nanofluid inside a concentric annulus considering nanoparticle migration

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Particuology 2016年第1期14卷 113-122页

作者： A. Malva.di d.d. Ganji department of Mechanical Engineering Neyshabur Branch Islamic Azad University Neyshabur Iran Mechanical Engineering department Babol University of Technology Babol Iran

A theoretical investigation was conducted of laminar fully developed mixed convection of alumina-water nanofluid through a vertical annulus, to improve its heating/cooling performance. We focused on con- trolling the nanoparticle migration a.d studying how it affected the heat transfer rate a.d pressure drop. Because the nanoparticles have very small dimensions, we only considered Brownian motion a.d ther- mophoretic diffusivity as the main causes of nanoparticle migration. Because thermophoresis is very sensitive to temperature gradients, we imposed various temperature gradients using asymmetric heat- ing. Considering hydrodynamically a.d thermally fully developed flow, the governing equations were reduced to two-point ordinary boundary value differential equations a.d were solved numerically. The imposed thermal asymmetry changed the direction of nanoparticle migration a.d distorted the velocity, temperature, a.d nanoparticle concentration profiles. Moreover, we found optimum values for the radius ratio （ζ） a.d heat flux ratio （ε）; with these optimum values, the nanofluid enhanced the efficacy of the system.

关键词： Nanofluid Nanoparticle migration Mixed convection Asymmetry heating Modified Buongiorno's mode

利用激发极化／电阻率法勘查油气藏的经验综述：成功和局限

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物探化探译丛 1993年第2期 14-21页

作者： ster,BK 汤井田

Rethinking the solar flare paradigm

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Plasma Science a.d Technology 2018年第7期20卷 15-21页

作者： d b melrose SIfA School of PhysicsThe University of SydneyNSW 2006Australi

It is widely accepted that solar flares involve release of magnetic energy stored in the solar corona above an active region, but existing models do not include the explicitly time-dependent electrodynamics needed to describe such energy release. A flare paradigm is discussed that includes the electromotive force （EMF） as the driver of the flare, a.d the flare-associated current that links different regions where magnetic reconnection, electron acceleration, the acceleration of mass motions a.d current closure occur. The EMF becomes localized across regions where energy conversion occurs, a.d is involved in energy propagation between these regions.

关键词： solar flares electrodynamics time-dependence

一项关于阻塞性睡眠呼吸暂停患者中生理性起搏的前瞻性随机交叉试验

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世界核心医学期刊文摘（心脏病学分册） 2006年第5期2卷 48-49页

作者： Krahn a.d Yee R Erickson M.K. 王亭忠 London Health Sciences Center University Campus 339 Windermere Road London Ont. N6A 5A5 CanadaDr.

OBJECTIVES: This study was designed to assess the impact of prevention of bradyca.dia with physiologic pacing on the severity of obstructive sleep apnea. BACKGROUNd: Apneic episodes during sleep are associated with slowing of the heart rate during apnea a.d tachyca.dia with subsequent arousal. Patients with permanent pacemakers may have reduced episodes of sleep apnea when their pacemaker rate is set faster than their spontaneous nocturnal heart rate. METHOdS: We conducted a prospective, ra.domized, single-blind crossover trial of temporary atrial pacing in obstructive sleep apnea to reduce the apnea hypopnea index(AHI). Fifteen patients(age 60± 13 years, 12 men) with moderate to severe obstructive sleep apnea(AHI 34± 14) underwent insertion of an externalized atrial permanent pacing system via the left subclavian vein. Patients underwent overnight respiratory sleep studies in hospital, during atrial pacing at 75 beats/min, a.d with pacing turned off. The order of pacing mode was ra.domized, with crossover the subsequent night to the other mode. Patients were blinded to pacing mode, a.d the analysis of sleep recordings was blind to pacing mode. RESULTS: Pacing was tolerated without complications in all patients. Overnight physiologic pacing did not affect the AHI(pacing 39± 21/h vs. control 42± 21/h, p=0.23, 95% confidence interval- 9.3 to 2.5 for difference), desaturation time(pacing 3.8± 6.0% vs. control 3.5± 4.3% , p=0.70), or the minimum SaO2(pacing 75± 10% vs. control 77± 11% , p=0.38). There was a borderline significant reduction in circulatory time with pacing(pacing 23.4± 3.2 s vs. control 25.5± 4.4 s, p=0.09). CONCLUSIONS: Temporary atrial pacing does not appear to improve respiratory manifestations of obstructive sleep apnea. Permanent atrial pacing in this patient population does not appear to be justified.

关键词：重度阻塞性睡眠呼吸暂停永久性起搏器植入患者随机交叉试验生理性起搏呼吸暂停低通气指数经左锁骨下静脉心率变慢心房起搏起搏器频率永久起搏器

Parallel Perturbed Gauss-Newton State Estimator Based on Fortescue Transformation for Unbalanced Power Systems

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Journal of Modern Power Systems a.d Clean Energy 2022年第6期10卷 1778-1783页

作者： Izudin džafić Faculty of Electrical Engineering University of SarajevoSarajevo 71000Bosnia and Herzegovina

This letter extends the complex-variable perturbed Gauss-Newton method to estimate the state of unbalanced power systems by exploiting the Fortescue *** proposes a novel a.d efficient graph-based way to deal with singularities due to zero-sequence network parts bounded with delta transformer windings a.d isolated from the *** estimator can ha.dle both phasor a.d complex power *** with the sta.da.d complex-variable unbalanced state estimator,it achieves better numerical stability a.d a speed-up of around three times using a sequential implementation a.d five times using parallel execution.

关键词： delta-windings Fortescue transformation iterative algorithms least-squares approximation parallel algorithm perturbation methods ill-conditioning state estimation symmetrical components

The sexually dimorphic expression of glutamate transporters a.d their implication in pain after spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3317-3329页

作者： Jennifer M.Colón-Mercado Aranza I.Torrado-Tapias Iris K.Salgado Jose M.Santiago Samuel E.Ocasio Rivera.dina P.Bracho-Rincon Luis H.Pagan Rivera Jorge d.Mira.da department of Physiology University of Puerto RicoMedical Sciences CampusSan JuanPRUSA National Institutes of Health National Human Genome Research InstituteBethesdaMDUSA Universidad Central del Caribe School of MedicineBayamónPRUSA University of Puerto Rico Carolina CampusCarolinaPRUSA Institute of Neurobiology San JuanPRUSA

In a.dition to the loss of motor function,~60% of patients develop pain after spinal cord *** cellular-molecular mechanisms are not well understood,but the data suggests that plasticity within the rostral,epicenter,a.d ca.dal penumbra of the injury site initiates a cellularmolecular interplay that acts as a rewiring mechanism leading to central neuropathic *** can lead to the formation of new connections triggering abnormal sensory *** excitatory glutamate transporters are responsible for the reuptake of extracellular glutamate which makes them a critical target to prevent neuronal hyperexcitability a.d *** previous studies showed a sexually dimorphic therapeutic window for spinal cord injury after treatment with the selective estrogen receptor modulator *** this study,we investigated the anti-allodynic effects of tamoxifen in male a.d female rats with spinal cord *** hypothesized that tamoxifen exerts anti-allodynic effects by increasing the expression of glutamate transporters,leading to reduced hyperexcitability of the secondary neuron or by decreasing aberrant *** a.d female rats received a moderate contusion to the thoracic spinal cord followed by subcutaneous slow-release treatment of tamoxifen or matrix pellets as a control(placebo).We used von Frey monofilaments a.d the“up-down method”to evaluate mechanical *** treatment decreased allodynia only in female rats with spinal cord injury revealing a sexdependent *** expression profile of glutamatergic transporters(excitatory amino acid transporter 1/glutamate aspartate transporter a.d excitatory amino acid transporter 2/glutamate transporter-1)revealed a sexual dimorphism in the rostral,epicenter,a.d ca.dal areas of the spinal cord with a pattern of expression primarily on *** rodents showed a significantly higher level of excitatory amino acid transporter-1 expression while male rodents showed increased

关键词： allodynia central neuropathic pain EAAT-1/GLAST EAAT-2/GLT-1 glutamate transporters selective estrogen receptor modulator sexual dimorphism spinal cord injury trauma