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A reversed-phase HPLC-UV assay for simultaneous analysis of EGCG and ecg of tea polyphenols in rat plasma

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A reversed-phase HPLC-UV assay for simultaneous analysis of ...

两岸三地药理学与临床药理学术会议

作者： FU Ting~1 LIANG Jun~1 HAN Guo-zhu~1 L(?) Li~1 LI Nan~2 (1.Department of Clinical Pharmacology, Dalian Medical University, Dalian 116044, China 2. Department of Analytical Chemistry, Dalian University of Technology, Dalian 116023, China)

Objective To develop a simple and specific reversed-phase HPLC-UV method for simultaneous determination of (-) Epigallocatechin-3-gallate (EGCG) and (-) Epicatechin-3-gallate (ecg),the main ac- tive ingredients of tea polyphenols (TP),in rat *** EGCG and ecg were eluted on a Kromasil C analytical column (150 mm×4.6 mm,5μm) protected by a C pre-column (4.6 mm×20 mm,10μm) with a linear gradient mobile phase composed of CH3CN (A)-0.1% citric acid (B),which was run from ini- tial 14 % A and 86 % B to 20 % A and 80 % B at a flow rate of 1.0 mL·min in 14 min,then changed to 14% A and 86% B at a gradient flow rate of 1.0-1.5 mL·min during 14-18 min,and then maintained until 22 min at a gradient flow rate of 1.5-1.0 mL·*** UV detector was set at 280 *** samples (200μL each) were prepared by liquid-liquid extraction procedure with double volumes of EtoAc and then evaporation of organic phase under N stream to dry,followed by reconstitution with 100μL of 20 % CHCN aqueous *** peak area ratios of analytes to vanillin as internal standard vs concentra- tion of analytes to construct calibration *** The HPLC resulted in base-line separation of vanillin,EGCG,ecg and other components;there was no interference from blank *** linear range was 0.5-300μg·mL for EGCG (r=0.9999) and 0.1-60μg·mL for ecg (r=0.9999).The intra- and inter-day precision (RSD) was better than 6.1% and 12.6%,respectively,and the average accuracy was between 86.25 %-103.14%.The extraction recovery of EGCG and ecg was 79.80 %-84.64% and 75.22 %-91.39 %,*** plasma samples were stable for at least 30 days at-20℃and 8 h at room temperature;EGCG,ecg and IS stock solutions 2 months at-20℃,and the EtoAc-extracted plas- ma samples 24 h at 4℃.Application of the method to the determination of EGCG and ecg in plasma of rats receiving iv 100 mg·kg of TP showed that these 2 compounds pharmacokinetically behaved as the two-compartment model and first-order kinetics,w

关键词： HPLC tea polyphenols EGCG ecg

Fetal ecg Extraction from Maternal Abdominal ecg Using Neural Network

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Journal of Software Engineering and Applications 2009年第5期2卷 330-334页

作者： M. A. HASAN M. I. IBRAHIMY M. B. I. REAZ 不详

Fecg (Fetal ecg) signal contains potentially precise information that could assist clinicians in making more appro-priate and timely decisions during pregnancy and labor. The extraction and detection of the Fecg signal from com-posite maternal abdominal signals with powerful and advance methodologies is becoming a very important requirement in fetal monitoring. The purpose of this paper is to illustrate the developed algorithms on Fecg signal extraction from the abdominal ecg signal using Neural Network approach to provide efficient and effective ways of separating and understanding the Fecg signal and its nature. The Fecg signal was isolated from the abdominal signal by neural network approach with different learning constant value and momentum as well so that acceptable signal can be con-sidered. According to the output it can be said that the algorithm is working satisfactory on high learning rate and low momentum value. The method appears to be exceedingly robust, correctly isolate the Fecg signal from abdominal ecg.

关键词： Neural Network Fecg Abdominal ecg Heart Rate

ecg、EGCG对两株耐药肿瘤细胞的细胞毒增敏作用研究

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中国天然药物 2004年第2期2卷 119-122页

作者：梁钢张肃黄志明黄仁彬梁宁生许佐良广西医科大学药理学教研室南宁530021 广西医科大学附属肿瘤医院药剂科南宁530021 北京大学医学部临床肿瘤学院免疫室北京100083

目的 :研究两种儿茶素成分ecg、EGCG是否对人耐药肝癌细胞BEL 74 0 4 /Adr和耐药口腔癌细胞KBV2 0 0存在细胞毒增敏作用及可能的机制。方法 :用MTT法检测药物对体外培养的细胞的毒性作用 ,用RT PCR法检测MDR1表达 ,流式细胞仪测定P gp... 详细信息

目的 :研究两种儿茶素成分ecg、EGCG是否对人耐药肝癌细胞BEL 74 0 4 /Adr和耐药口腔癌细胞KBV2 0 0存在细胞毒增敏作用及可能的机制。方法 :用MTT法检测药物对体外培养的细胞的毒性作用 ,用RT PCR法检测MDR1表达 ,流式细胞仪测定P gp表达及细胞内Rh 12 3含量。结果 :两种儿茶素成分在 10 0 μg·ml-1以下剂量对两株耐药肿瘤细胞的抑制率均小于 10 % ,6 0 μg·ml-1ecg或 14 μg·ml-1EGCG联合 0 8μg·ml-1ADM或 0 12 μg·ml-1VCR时MDR1下降 2 3 9%～ 38 6 % ,两种儿茶素成分与抗肿瘤药物联合应用可使P gp表达下降 ,能明显提高细胞内Rh 12 3的含量。结论 :儿茶素成分ecg、EGCG与ADM或VCR联合应用可增强耐药肿瘤细胞BEL 74 0 4 /Adr和耐药口腔癌细胞KBV2 0 0的细胞毒作用 ,其机制可能与降低MDR1 mRNA表达、下调P gp表达及抑制P gp的功能有关。

关键词： ecg EGCG 肿瘤细胞毒副作用增敏作用多药耐药儿茶素化疗实验

The QRS Complex Detection of ecg Signal Based on IPCMM Algorithm

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The QRS Complex Detection of ECG Signal Based on IPCMM Algor...

第三十九届中国控制会议

作者： Wei Li Bin Li Hailong Meng Fengjuan Qiao Xiaoyun Liu Shuwang Zhou Jiyong Xu School of Mathematics and Statistics Qilu University of Technology(Shandong Academy of Sciences) Shandong Computer Science Center

QRS complex detection plays an important role in the identification and classification of ecg *** this paper,a new QRS complex detection algorithm named II-P＆T algorithm is proposed based on I-P＆T algorithm by means of the IPCMM algorithm rather than fdatool to generate a bandpass digital filter and a lowpass digital *** demonstrates that on the MIT-BIH database,the performance of the proposed II-P＆T algorithm is better than P＆T and I-P＆T algorithm in terms of sensitivity（Se）,positive predictivity（PP）,detection error（DER） of the proposed algorithm with results of Se=99.62%,PP=99.54%,and DER=0.84%.The ecg classification accuracy of the II-P＆T+SUM algorithm reaches 97.68%,which is higher than the I-P＆T+SUM ***,II-P＆T algorithm can accurately locate the QRS complex wave and reduce the number of false detections and can be used to the process of the feature extraction of ecg signal.

关键词： QRS complex P&T algorithm IPCMM algorithm ecg

CLINICAL STUDY ON METHODS OF TREATMENT AND PREVENTION OF MYOCARDIAL ISCHEMIA RESULT FROM CEREBRAL ISCHEMIA AND ecg

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现代电生理学杂志 2005年第2期12卷 84-85页

作者： LIUMingshun LIUQingrui MEIFengjun LIFengluan GULanjie ZHAOJingxia FourthAffiliatedHospital HebeiMedicalUniversityShijiazhuang050011

目的:探讨脑缺血引起心肌缺血的预防和治疗方法以及心电图改变。方法:研究了四种防治方法并观察了其心电图的改变。结果:稀释+高压氧方法,有效率是最高的。它的有效率是83.9%,心电图改变是明显的。结论:稀释加高压氧方法是防治脑缺血引... 详细信息

目的:探讨脑缺血引起心肌缺血的预防和治疗方法以及心电图改变。方法:研究了四种防治方法并观察了其心电图的改变。结果:稀释+高压氧方法,有效率是最高的。它的有效率是83.9%,心电图改变是明显的。结论:稀释加高压氧方法是防治脑缺血引起心肌缺血的较理想的方法,值得临床应用推广。

关键词： ecg 脑缺血心肌缺血防治措施心电图高压氧

Compression of ecg signal using video codec technology-like scheme

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Journal of Biomedical Science and Engineering 2008年第1期1卷 22-26页

作者： Dihu Chen Sheng Yang Department of Precision Machinery & Instrumentation University of Science and Technology of China.Hefei 230027 China.

In this paper, we present a method using video codec technology to compress ecg signals. This method exploits both intra-beat and inter-beat correlations of the ecg signals to achieve high compression ratios (CR) and a low percent root mean square difference (PRD). Since ecg signals have both intra-beat and inter-beat redundancies like video signals, which have both intra-frame and inter-frame correlation, video codec technology can be used for ecg compression. In order to do this, some pre-process will be needed. The ecg signals should firstly be segmented and normalized to a sequence of beat cycles with the same length, and then these beat cycles can be treated as picture frames and compressed with video codec technology. We have used records from MIT-BIH arrhythmia database to evaluate our algorithm. Results show that, besides compression efficiently, this algorithm has the advantages of resolution adjustable, random access and flexibility for irregular period and QRS false detection.

关键词： ecg compression video CODEC QRS detection arithmetic coding

AUTOMATIC CLASSIFICATION OF ecg USING ARTIFICIAL NEURAL NETWORKS

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Chinese Journal of Biomedical Engineering(English Edition) 1996年第3期5卷 135-138页

ＡＵＴＯＭＡＴＩＣＣＬＡＳＳＩＦＩＣＡＴＩＯＮＯＦＥＣＧＵＳＩＮＧＡＲＴＩＦＩＣＩＡＬＮＥＵＲＡＬＮＥＴＷＯＲＫＳＡＵＴＯＭＡＴＩＣＣＬＡＳＳＩＦＩＣＡＴＩＯＮＯＦＥＣＧＵＳＩＮＧＡＲＴＩＦＩＣＩＡＬＮＥＵＲＡＬＮＥ... 详细信息

ＡＵＴＯＭＡＴＩＣＣＬＡＳＳＩＦＩＣＡＴＩＯＮＯＦＥＣＧＵＳＩＮＧＡＲＴＩＦＩＣＩＡＬＮＥＵＲＡＬＮＥＴＷＯＲＫＳＡＵＴＯＭＡＴＩＣＣＬＡＳＳＩＦＩＣＡＴＩＯＮＯＦＥＣＧＵＳＩＮＧＡＲＴＩＦＩＣＩＡＬＮＥＵＲＡＬＮＥＴＷＯＲＫＳＣ．Ｌ．Ｐｅｎｇ，Ｚ．...

关键词： ecg OF USING CLASSIFICATION NETWORKS NEURAL ARTIFICIAL AUTOMATIC

A Novel Portable One Lead ecg Monitor with Low-Cost and Long-Time Recording Based on NUC501

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A Novel Portable One Lead ECG Monitor with Low-Cost and Long...

2010 Chinese Control and Decision Conference

作者： Lihuang She~1,Jinshuan Zhao~1,Shi Zhang~1,Guohua Wang~1,Gang Wang~1 1.School of Information Science and Engineering,Northeastern University,Shenyang,110004

＜正＞In this paper,a portable low-cost long-time one lead Electrocardiogram（ecg） Monitor is present,which is powered by one dry battery and based on *** management module,analogous amplifier and Advanced RISC Machines（ARM） are used in hardware *** hardware driver,digital filter,modified baseline drift method and difference threshold method are taken in software *** monitor gathers ecg signal through cable from user’s body.A prototype instrument has been finally produced and will be put into the clinical *** notch filter and median filter are used to process the ***/her ecg tracing is displayed lively on Liquid Crystal Display （LCD） *** the heart rate is shown precisely on LCD screen and displayed with led *** monitor also can storage and transport data to computer through Universal Serial Bus（USB） *** being powered by one dry battery,it works twenty-four *** there is any abnormally changes of heart rate,this instrument will be given alarm through the *** testing results show that this monitor is low power consumption,light-weight,accurate and *** can care for cardiac patients very good and provide a reliable cost-effective choice for cardio-path.

关键词： Long-time ecg NUC501 Digital filter Difference Threshold Method

A real-time ecg signal classification algorithm

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A real-time ECG signal classification algorithm

第三十九届中国控制会议

作者： Yao Xitong Dai Yu Zhang Jianxun Nankai University Institute of Robotics ＆ Automatic Information System

Embedded systems are widely used in diagnostic equipment due to their small size,low power consumption,and low ***,because of their small memory and low frequency,some high-precision algorithms are restricted from achieving the desired *** at the above this problems,a simple deep neural network algorithm is *** addition,the electrocardiogram（ecg） signal is a specific signal and it is difficult for a fixed classifier to meet the accuracy ***,an autonomous learning algorithm based on posterior probability estimation is used to screen heartbeats that are both characteristic and *** beats are marked by the doctor and will then be used to fine-tune the classifier ***,the algorithm proposed by the author is compared with other ecg signal classification *** classification accuracy of the algorithm for supraventricular arrhythmias and ventricular arrhythmias reached 99.3% and 99.6%,*** average time for the algorithm to classify a single heartbeat is 43.68 ms.

关键词： embedded systems ecg deep neural network autonomous learning