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一种谱片量化参数数值标准化方法的提取 被引量:2
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作者 刘玉斌 杨志伊 +2 位作者 师杭军 许留存 沙新善 《润滑与密封》 CAS CSCD 北大核心 2001年第6期31-32,共2页
本文分析了已有的谱片量化参数数值标准化方法的不足,提取了一种简单准确的谱片量化参数数值标准化的新方法,并从理论上证明了该方法的正确和可行性。
关键词 谱片量化参数 技术 磨屑 标准化 状态监测 机器
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旋转式铁谱仪制得谱片上磨屑沉积规律的研究 被引量:2
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作者 刘玉斌 李柱国 杨志伊 《润滑与密封》 EI CAS CSCD 北大核心 2003年第4期39-42,共4页
从KTP-1型旋转式铁谱仪中磨屑沉积的基本原理出发,通过对制谱时谱片上油样中磨屑的运动学和动力学分析,利用流体力学、电磁学、理论力学等的相关理论和方法,推出了一定尺寸磨屑在谱片上沉积位置的理论表达式及等几率沉积的结论,作为定... 从KTP-1型旋转式铁谱仪中磨屑沉积的基本原理出发,通过对制谱时谱片上油样中磨屑的运动学和动力学分析,利用流体力学、电磁学、理论力学等的相关理论和方法,推出了一定尺寸磨屑在谱片上沉积位置的理论表达式及等几率沉积的结论,作为定性铁谱分析中,确定谱片上磨屑沉积位置的理论依据。 展开更多
关键词 旋转式铁 磨屑沉积 谱片 等几率沉积 磨屑群
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用于激光产生的高能X射线源能谱诊断的滤片堆栈谱仪的研制 被引量:3
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作者 于明海 谭放 +9 位作者 闫永宏 陈佳 张天奎 韩丹 吴玉迟 董克攻 朱斌 杨靖 王少义 谷渝秋 《原子能科学技术》 EI CAS CSCD 北大核心 2017年第6期1090-1095,共6页
为了诊断基于激光的短脉冲、高强度的高能X射线源能谱特性,本文利用不同材料和厚度的金属滤片和记录介质研制了一套滤片堆栈谱仪。基于Greval算法发展了能谱反解程序,并使用蒙特卡罗程序Geant4模拟得到了谱仪的响应函数。在星光Ⅲ激光... 为了诊断基于激光的短脉冲、高强度的高能X射线源能谱特性,本文利用不同材料和厚度的金属滤片和记录介质研制了一套滤片堆栈谱仪。基于Greval算法发展了能谱反解程序,并使用蒙特卡罗程序Geant4模拟得到了谱仪的响应函数。在星光Ⅲ激光装置上验证了谱仪的可靠性,获得了ps激光与固体靶相互作用产生的10 keV^3 MeV轫致辐射能谱,从而验证了谱仪的可靠性。 展开更多
关键词 堆栈 X射线 测量 反解
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利用自适应时间片梯度谱对镜头转换进行精细识别
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作者 刘铁岩 张旭东 彭应宁 《中国图象图形学报(A辑)》 CSCD 北大核心 2003年第8期883-889,共7页
提出了一种利用视频序列的自适应时间片梯度谱对镜头转换类型进行精细识别的算法 .在这个算法中 ,首先提出了自适应时间片梯度谱的概念 ,并且在此基础上 ,提出了用于识别镜头转换类型的模板构造和匹配算法 ,同时还给出了一种描述语言作... 提出了一种利用视频序列的自适应时间片梯度谱对镜头转换类型进行精细识别的算法 .在这个算法中 ,首先提出了自适应时间片梯度谱的概念 ,并且在此基础上 ,提出了用于识别镜头转换类型的模板构造和匹配算法 ,同时还给出了一种描述语言作为模板的软描述方法 ,用以适应不同的图象尺寸和镜头转换的持续时间 .实验结果表明 ,这种方法在多数情况下具有很好的识别效果 ,只是在两个镜头转换非常相近时 ,识别效果差些 ,另外 ,该方法识别速度快 ,同时具有很强的鲁棒性和可扩展性 。 展开更多
关键词 自适应时间梯度 精细识别 镜头转换 鲁棒性 可扩展性 视频分析技术
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利用铁谱分析技术对汽车发动机状态进行监测 被引量:4
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作者 刘玉斌 师杭军 +3 位作者 许留存 郭伟 张成 高栋梁 《车用发动机》 北大核心 2001年第4期36-39,共4页
利用铁谱分析技术制成发动机在用机油油样谱片 ,研究了谱片上磨屑总量累积效应和大磨屑总量累积效应两个参数与发动机技术状态的对应关系 ;用 3台同型号车用发动机机油取样检测 ,指出在检测过程中 ,若发现发动机存在故障隐患 ,则需对谱... 利用铁谱分析技术制成发动机在用机油油样谱片 ,研究了谱片上磨屑总量累积效应和大磨屑总量累积效应两个参数与发动机技术状态的对应关系 ;用 3台同型号车用发动机机油取样检测 ,指出在检测过程中 ,若发现发动机存在故障隐患 ,则需对谱片上磨屑的数量、形状、尺寸、表面形貌及颜色做进一步的详细分析 ,以确定故障原因及其部位。 展开更多
关键词 发动机 分析技术 状态监测 汽车 故障分析 谱片参数
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基于铁谱技术的常见材料的识别
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作者 柳丹娜 樊瑜瑾 叶超 《煤矿机械》 北大核心 2008年第5期214-216,共3页
大型机械设备各摩擦副的工作环境恶劣,磨损状态复杂,很难精确判断磨损部位。材料识别是磨粒识别的一部分,材料的准确识别可以让多摩擦副机械设备磨损部位的确定达到一个更好的定位效果;基于铁谱技术,以铁谱显微镜及谱片加热法为手段,进... 大型机械设备各摩擦副的工作环境恶劣,磨损状态复杂,很难精确判断磨损部位。材料识别是磨粒识别的一部分,材料的准确识别可以让多摩擦副机械设备磨损部位的确定达到一个更好的定位效果;基于铁谱技术,以铁谱显微镜及谱片加热法为手段,进行常用材料的识别。 展开更多
关键词 技术 显微镜 谱片加热法 常用材料
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铁谱分析技术在大型机组运行中发挥的作用 被引量:2
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作者 伏瑞军 祁舜斌 张晓霞 《科技资讯》 2010年第7期97-98,共2页
机械设备在运行过程中,润滑油不但减少了这些零部件的摩擦和磨损,而且随着它的流动,也会不断地把零部件磨损的产物——磨屑带离摩擦表面,使这些磨屑悬浮于油液中,润滑油中的磨损颗粒携带着有关机械磨损状态的详细信息,这些信息通过磨损... 机械设备在运行过程中,润滑油不但减少了这些零部件的摩擦和磨损,而且随着它的流动,也会不断地把零部件磨损的产物——磨屑带离摩擦表面,使这些磨屑悬浮于油液中,润滑油中的磨损颗粒携带着有关机械磨损状态的详细信息,这些信息通过磨损颗粒的浓度、尺寸、形状及组成表现出来,根据这些特征,可以断定零件所处的磨损状态以及该状态下发生的磨损类型。 展开更多
关键词 分析 磨损 磨粒 大型机组 谱片
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S-西酞普兰草酸盐片溶出度测定方法的研究 被引量:1
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作者 严轶琛 曾志杰 +1 位作者 黄兰 杨雪梅 《南方医科大学学报》 CAS CSCD 北大核心 2008年第3期503-504,共2页
目的建立测定S-西酞普兰草酸盐片溶出度的方法。方法采用紫外分光光度法,水为溶剂,转速为50r·min-1,检测波长为240nm。结果在0.002 ̄0.030mg/ml浓度范围内,其线性方程为:A=42.5981C+0.0234(r=0.9998,n=7),30min内产品的溶出率达到... 目的建立测定S-西酞普兰草酸盐片溶出度的方法。方法采用紫外分光光度法,水为溶剂,转速为50r·min-1,检测波长为240nm。结果在0.002 ̄0.030mg/ml浓度范围内,其线性方程为:A=42.5981C+0.0234(r=0.9998,n=7),30min内产品的溶出率达到80%以上。辅料对主药测定无干扰,回收率达到99%以上,RSD值低于1.0%。结论方法准确、简便,可用于S-西酞普兰草酸盐片溶出度的测定,所研制的S-西酞普兰草酸盐片溶出度符合药典对新药的技术要求。 展开更多
关键词 溶出度 S-西酞兰草酸盐 紫外分光光度法
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基于多尺度计算方法的活体磁共振谱自动相位矫正和代谢物定量分析(英文)
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作者 张晓东 胡小平 《波谱学杂志》 CAS CSCD 北大核心 2014年第1期32-39,共8页
活体多片磁共振谱成像(MRSI)产生大量的波谱数据,因此需要使用自动的谱数据分析方法来获得不同组织代谢产物的定量分布图.然而,活体波谱通常产生严重的谱和基线变形,使得基于曲线拟合的谱定量数据分析方法失效.该文应用多尺度分析(Multi... 活体多片磁共振谱成像(MRSI)产生大量的波谱数据,因此需要使用自动的谱数据分析方法来获得不同组织代谢产物的定量分布图.然而,活体波谱通常产生严重的谱和基线变形,使得基于曲线拟合的谱定量数据分析方法失效.该文应用多尺度分析(Multiscale)方法自动确定兴趣代谢物在频率空间的谱峰特征(位置和线宽),然后通过叠代运算对该代谢物对应的谱峰进行独立的自动相位矫正和线型拟合.大脑波谱成像的实验结果表明,该方法可以方便、有效的获得代谢产物在大脑的分布,特别适宜于多片磁共振谱成像的代谢产物定量分析. 展开更多
关键词 活体多磁共振成像(MRSI) 多尺度分析方法 线型拟合 自动相位矫正
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Preliminary Study on Spectra Diagnosis Model for Nitrogen Nutrition in Rice Leaf 被引量:4
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作者 李晓利 刘明博 +1 位作者 楼佳 唐延林 《Agricultural Science & Technology》 CAS 2011年第2期168-170,共3页
[Objective] The aim was to build spectral diagnosis model for nitrogen nutrition in rice leaf.[Method] Through determination of transmission,absorption spectra and nitrogen content on rice leaves of different rice var... [Objective] The aim was to build spectral diagnosis model for nitrogen nutrition in rice leaf.[Method] Through determination of transmission,absorption spectra and nitrogen content on rice leaves of different rice varieties(Xiangyou 109 and Shanyou 98),different growth periods and different nitrogen levels,we analyzed the correlation between leaf spectra and their nitrogen contents,and built prediction model of spectral index for nitrogen content in rice leaf.[Result] The detection precision of this model was above 80% that can be used on diagnosing of rice nitrogen nutrition.[Conclusion] The study provided evidence for monitoring nitrogen nutrition status of rice. 展开更多
关键词 RICE LEAF Nitrogen content Spectral index MODEL
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High Resolution Determination of Ondansetron in Human Plasma by HPLC and Pharmacokinetics of Orally Disintegrating Tablets 被引量:1
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作者 陈伟 吴伟 +4 位作者 汪杨 黄敏 阙俐 胡弢 孙宁云 《Journal of Chinese Pharmaceutical Sciences》 CAS 2005年第3期162-168,共7页
Ahn To develop a high resolution HPLC method for the determination of ondansetron in human plasma and to study the pharmacokinetics of ondansetron in orally disintegrating tablets. Methods HPLC determination involved ... Ahn To develop a high resolution HPLC method for the determination of ondansetron in human plasma and to study the pharmacokinetics of ondansetron in orally disintegrating tablets. Methods HPLC determination involved liquid-liquid extraction, separation on a CN column and ultraviolet detection at 310 ran with granisetron as an internal standard. Pharmacokinetics and bioequivalence of ondansetron in orally disintegrating tablets by direct compression and conventional 8 mg tablets were evaluated and compared in 20 healthy human male volunteers after a single oral dose in a randomized cross-over study. Results The limit of quantification was 0.25 ng· mL^-1. The recovery was about 85 % or over for ondan setron and about 90% for internal standard. Linearity was good within the concentration range of 0.5 - 50 ng·mL^-1 with r^2 ranging from 0.997 1 to 0.999 9. Intra- and inter-assay coefficients of variation ranged from 1.78% to 2.38% and 3.88% -5.19%, respectively. Accuracies for spiked concentrations of 2.0, 10.0, and 30.0 ng·mL^-1 were 104.7% ±4.4%, 102.2% ± 1.1%, and99.51% ±2.34%, respectively. Pharmacokinetic parameters of AUCo-t, AUCo-∞ , Cmax, Tmax, and T1/2 were 230.2 ± 78.0 ng·h·L^-1 , 265.2± 101.5 ng·h·mL^-1, 35.67 ± 8.94 ng·mL^-l, 1.51 ±0.79 h, and 5.00± 1.41 h for orally disintegrating tablets, respectively. The analysis of variance did not show any significant difference between orally disintegrating tablets and conventional tablets, and 90% confidence intervals fell within the acceptable range for bioequivalence. Conclusion High resolution HPLC method has been set up and applied in pharmacokinetic evaluation of ondansetron in orally disintegrating tablets. 展开更多
关键词 ONDANSETRON HPLC orally disintegrating tablets PHARMACOKINETICS
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Pharmacokinetics of nifedipine sustained-release tablets in healthy Chinese volunteers 被引量:3
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作者 武静 王本杰 +2 位作者 魏春敏 卜凡龙 郭瑞臣 《Journal of Chinese Pharmaceutical Sciences》 CAS 2007年第3期192-196,共5页
Aim To establish a LC-MS method for determining the concentration of nifedipine in human plasma and to evaluate the pharmacokinetic characteristics of nifedipine sustained-release tablets. Methods A XB-C18 (5 μm, 4.... Aim To establish a LC-MS method for determining the concentration of nifedipine in human plasma and to evaluate the pharmacokinetic characteristics of nifedipine sustained-release tablets. Methods A XB-C18 (5 μm, 4.6 mm ×150 mm) column and a mobile phase of methanol: 0.01 mol·L^-1ammonium acetate (60:40, V/V) were used to separate nifedipine, the detections was accuracy under atmosperic pressure electronic spray ionization (AP-ESI) mode and ion mass spectrum (m/z) of 314.9 [M+H]^+ for nifedipine, and 320.8 [M+H]^+ for lorazepam (Internal Standard, IS). Results The linear range of nifedipine was 0.3 - 80 ng·mL^-1 ( r = 0.9997), and the limit of quantitation (LOQ) was 0.3 ng·mL^-1. The nifedipine pharmacokinetic parameters after a single dose of 20 mg nifedipine sustained-release tablets test (T) or reference (R) were as the followings, t1/2 (6.73 ± 2.00) h and (7.04 ± 2.18) h, Tmax (4.28 ± 0.70) h and (4.48 ± 0.70) h, Cmax(39.66 ± 10.58) ng·mL^-1 and (40.19 ± 10.97) ng·mL^-1, AUC0-36 (391.63 ± 108.55) ng·mL^-1·h and (387.57 ± 121.51) ng·mL^-1·h, and AUC0-∞ (408.28 ± 121.16) ng·mL^-1·h and (406.15 ± 133.13) ng·mL^-1·h. The relative bioavailability of nifedipine sustained-release tablets (test) was (103.02 ± 13.93) %. Conclusion LC-MS method for the determination of concentrations of nifedipine in human plasma was sensitive and accurate, and could be used in nifedipine bioavailability and pharmacokinetic studies. 展开更多
关键词 Nifedipine sustained-release tablets LC-MS PHARMACOKINETICS BIOEQUIVALENCE
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Determination of Piperazine Ferulate in Human Plasma by HPLC and Its Pharmacokinetic Study 被引量:1
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作者 袁桂艳 王本杰 +2 位作者 魏春敏 刘焕君 郭瑞臣 《Journal of Chinese Pharmaceutical Sciences》 CAS 2006年第4期238-242,共5页
Aim To establish a sensitive HPLC method for determination of piperazine ferulate and to study its pharmacokinetics in healthy volunteers. Methods Piperazine ferulate was separated on a Shimadzu C_ 18 column with acet... Aim To establish a sensitive HPLC method for determination of piperazine ferulate and to study its pharmacokinetics in healthy volunteers. Methods Piperazine ferulate was separated on a Shimadzu C_ 18 column with acetic acid (0.1%)-methanol (60 ∶ 40, V/V) as mobile phase after liquid-liquid extraction, and detection was performed at 310 nm. Piperazine ferulate pharmacokinetic parameters after a single oral dose of 200 mg of piperazine ferulate dispersible tablets in 20 healthy male volunteers were calculate... 展开更多
关键词 piperazine ferulate dispersible tablet PHARMACOKINETICS HPLC
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HPLC Determination of Harpagoside and Cinnamic Acid in Radix Scrophulariae 被引量:5
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作者 谢丽华 刘洪宇 +4 位作者 徐秉玖 王璇 王建华 徐风 蔡少青 《Journal of Chinese Pharmaceutical Sciences》 CAS 2001年第3期148-151,共4页
A gradient HPLC method was established for the determination of harpagoside and cinnamic acid in Radix Scrophulariae (Xuanshen) and a proposition was put forward for the lowest content of the characteristic and active... A gradient HPLC method was established for the determination of harpagoside and cinnamic acid in Radix Scrophulariae (Xuanshen) and a proposition was put forward for the lowest content of the characteristic and active constituent (harpagoside) for qualified Radix Scrophulariae. The experimental conditions were as follows: Ultrasphere ODS column (250 mm 4.6 mm, 5 mm), mobile phase: acetonitrile-water (containing 1.0% acetic acid) (20:8050:50) (20 min), flow-rate 1 mLmin-1, room temperature, detection wavelength 278 nm. Twenty-eight samples of Xuan-shen (Radix Scrophulariae) from different districts of China were analyzed and the contents of harpagoside and cinnamic acid in Xuan-shen were 0.041~0.244% and 0.012~0.068% respectively. The recoveries (RSD)% were 97.13(0.80)% for harpagoside and 99.38(0.51)% for cinnamic acid. The method is simple and accurate. It can be used for the quality control of Radix Scrophulariae. We propose that the content of harpagoside in qualified Radix Scrophularia should be no less than 0.05%. 展开更多
关键词 Scrophularia ningpoensis HARPAGOSIDE Cinnamic acid HPLC
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Relationship Between Leaf Structure and Aloin Content in Six Species of Aloe L. 被引量:12
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作者 李景原 王太霞 +1 位作者 沈宗根 胡正海 《Acta Botanica Sinica》 CSCD 2003年第5期594-600,共7页
The leaf structure, content and the storage location of aloin in the leaves of six species of Aloe L. were studied by means of semi-thin section, high performance liquid chromatography (HPLC) and fluorescent microscop... The leaf structure, content and the storage location of aloin in the leaves of six species of Aloe L. were studied by means of semi-thin section, high performance liquid chromatography (HPLC) and fluorescent microscope. Results showed that all leaves consisted of epidermis, chlorenchyma, aquiferous tissue and vascular bundles. The leaves had the xeromorphic characteristics, including thickened epidermal cell wall, thickened cuticle, sunken stomata and well-developed aquiferous tissue. With the exception of thus, there were remarkable differences in leaf structure among the six species. The chlorenchyma cells were similar to palisade tissues in Aloe arborescens Mill. and A. mutabilis Pillans, but isodiametric in A. vera L., A. vera L. var. chinensis Berg., A. saponaria Hawer and A. greenii Bali. A. arborescens, A. mutabilis, A. very and A. vera var. chinensis included large parenchymatous cells at the vascular bundles, whereas no such cells were observed at the vascular bundles of A. saponaria and A. greenii. In A. arborescens, A. mutabilis and A. vera, the aquiferous tissue sheaths were present and composed of a layer of small parenchymatous cells without chloroplasts around the aquiferous tissue. While there were no aquiferous tissue sheaths in A. vera var. chinensis, A. saponaria and A. greenii. The HPLC revealed that the content of aloin was high in A. arborescens, low in A. vera, and very low in A. saponaria among the six species. The fluorescent microscopy showed that the yellow-green globule only appeared in the large parenchymatous cells of vascular bundles, vascular bundle sheath and aquiferous tissue sheath, but not in the chlorenchyma and aquiferous tissue. Consequently, the large parenchymatous cells of vascular bundles, vascular bundle sheath and aquiferous tissue sheath were the storage location of aloin. They were positively correlated with the content of aloin. 展开更多
关键词 ALOE leaf structure aloin content high performance liquid chromatography (HPLC) fluorescent microscope semi-thin section
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Method for quantification of prazosin in dog plasma and its application to pharmacokinetic study
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作者 张妮萍 余书勤 +4 位作者 王辉 申艳艳 徐师 张玲 许茜 《Journal of Southeast University(English Edition)》 EI CAS 2011年第2期217-221,共5页
A simple and sensitive high performance liquid chromatography method using fluorescence detection (HPLC- FLD) and a one-step single solvent extraction for the determination of prazosin(PZS) in dog plasma is develo... A simple and sensitive high performance liquid chromatography method using fluorescence detection (HPLC- FLD) and a one-step single solvent extraction for the determination of prazosin(PZS) in dog plasma is developed and validated. After extraction with ether, the chromatographic separation of PZS is carried out using a reverse phase C18 column ( 150 mm ×4.6 mm, 5 μm) with a mobile phase of 30% acetonitrile and 70% acetic acid-sodium acetate buffer solution (pH = 3.6) and quantified by fluorescence detection operated with an excitation wavelength of 258 nm and an emission wavelength of 387 nm. The flow rate of the mobile phase is 1.0 mL/min and the retention time of PZS and the internal standard is found to be 4. 4 and 5. 8 rain, respectively. The calibration curve is linear within a concentration range from 1.0 to 1 000.0 ng/mL ( P 〉 0. 998). The limit of detection is 0.4 ng/mL. The inter-day coefficient of variation (COV) of the calibration standards is below 5.0% and the mean accuracy is in the range from 92. 7% to 104. 2%. Moreover, by analyzing quality control plasma samples for three days, the results show that the method is precise and accurate, for the intra- and inter- day COV within 10% and the accuracy from 95.9% to 112.7%. The developed and validated method is successfully applied to phannacokinetic study for the preclinical evaluation of a new peroral PZS-sulfobutyl ether beta-cyclodextrin (PZS-SBE-β-CD) inclusion complex tablets (test preparation), which demonstrates that the test preparation released PZS is conducted in a slow and controlled way, and the relative bioavailability of the test preparation is found to be 105.0%. 展开更多
关键词 prazosin PZS PZS-sulfobutyl ether beta-cyclodextrin (PZS-SBE-[3-CD) inclusion complex tablets highperformance liquid chromatography (HPLC) pharmacokinetics
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MiRNA profile in esophageal squamous cell carcinoma:Downregulation of miR-143 and miR-145 被引量:31
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作者 Bing-Li Wu Li-Yan Xu +5 位作者 Ze-Peng Du Lian-Di Liao Hai-Feng Zhang Qiao Huang Guo-Qiang Fang En-Min Li 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第1期79-88,共10页
AIM:To investigate the expression profile of miRNA in esophageal squamous cell carcinoma(ESCC).METHODS:The expression profile of miRNA in ESCC tissues was analyzed by miRNA microarray.The expression levels of miR-143 ... AIM:To investigate the expression profile of miRNA in esophageal squamous cell carcinoma(ESCC).METHODS:The expression profile of miRNA in ESCC tissues was analyzed by miRNA microarray.The expression levels of miR-143 and miR-145 in 86 ESCC patients were determined by real-time polymerase chain reaction(PCR) using TaqMan assay.The mobility effect was estimated by wound-healing using esophageal carcinoma cells transfected with miRNA expression plasmids.RESULTS:A set of miRNAs was found to be deregulated in the ESCC tissues,and the expression levels of miR-143 and-145 were significantly decreased in most of the ESCC tissues examined.Both miR-143 and miR-145 expression correlated with tumor invasion depth.The transfection of human esophageal carcinoma cells with miR-143 and miR-145 expression plasmids resulted in a greater inhibition of cell mobility,however,the protein level of the previously reported target of miR-145,FSCN1,did not show any significant downregulation.CONCLUSION:These findings suggest that the deregulation of miRNAs plays an important role in the progression of ESCC.Both miR-143 and miR-145 might act as anti-oncomirs common to ESCC. 展开更多
关键词 Esophageal squamous cell carcinoma MicroRNA MIR-143 MIR-145 Tumor invasion depth
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Extracting Feature Bands for Damaged Rice Leaves by Planthoppers Using Multi-spectral Imaging Technology
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作者 曹鹏飞 李宏宁 +2 位作者 杨卫平 林立波 冯洁 《Agricultural Science & Technology》 CAS 2013年第11期1642-1645,1669,共5页
[Objective] The aim of this study was to extract effective feature bands of damaged rice leaves by planthoppers to make identification and classification rapidly from great amounts of imaging spectral data. [Method] T... [Objective] The aim of this study was to extract effective feature bands of damaged rice leaves by planthoppers to make identification and classification rapidly from great amounts of imaging spectral data. [Method] The experiment, using multi-spectral imaging system, acquired the multi-spectral images of damaged rice leaves from band 400 to 720 nm by interval of 5 nm. [Result] According to the principle of band index, it was calculated that the bands at 515, 510, 710, 555, 630, 535, 505, 530 and 595 nm were having high band index value with rich information and little correlation. Furthermore, the experiment used two classification methods and calcu-lated the classification accuracy higher than 90.00% for feature bands and ful bands of damaged rice leaves by planthoppers respectively. [Conclusion] It can be con-cluded that these bands can be considered as effective feature bands to identify damaged rice leaves by planthoppers quickly from a large scale of crops. 展开更多
关键词 Feature bands Multi-spectral imaging Damaged rice leaves Planthop-pers Classification accuracy
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Wnt5a participates in hepatic stellate cell activation observed by gene expression profile and functional assays 被引量:18
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作者 Wu-Jun Xiong Li-Juan Hu +4 位作者 Yi-Cheng Jian Li-Jing Wang Ming Jiang Wei Li Yi He 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第15期1745-1752,共8页
AIM:To identify differentially expressed genes in quiescent and activated hepatic stellate cells(HSCs)and explore their functions.METHODS:HSCs were isolated from the normal Sprague Dawley rats by in suit perfusion of ... AIM:To identify differentially expressed genes in quiescent and activated hepatic stellate cells(HSCs)and explore their functions.METHODS:HSCs were isolated from the normal Sprague Dawley rats by in suit perfusion of collagenase and pronase and density Nycodenz gradient centrifugation.Total RNA and mRNA of quiescent HSCs,and cultureactivated HSCs were extracted,quantified and reversely transcripted into cDNA.The global gene expression profile was analyzed by microarray with Affymetrix rat genechip.Differentially expressed genes were annotated with Gene Ontology(GO)and analyzed with Kyoto encyclopedia of genes and genomes(KEGG)pathway using the Database for Annotation,Visualization and Integrated Discovery.Microarray data were validated by quantitative real-time polymerase chain reaction(qRTPCR).The function of Wnt5a on human HSCs line LX-2 was assessed with lentivirus-mediated Wnt5a RNAi.The expression of Wnt5a in fibrotic liver of a carbon tetrachloride(CCl4)-induced fibrosis rat model was also analyzed with Western blotting.RESULTS:Of the 28 700 genes represented on this chip,2566 genes displayed at least a 2-fold increase or decrease in expression at a P<0.01 level with a false discovery rate.Of these,1396 genes were upregulated,while 1170 genes were downregulated in culture-activated HSCs.These differentially expressed transcripts were grouped into 545 GO based on biological process GO terms.The most enriched GO terms included response to wounding,wound healing,regulation of cell growth,vasculature development and actin cytoskeleton organization.KEGG pathway analysis revealed that Wnt5a signaling pathway participated in the activation of HSCs.Wnt5a was significantly increased in cultureactivated HSCs as compared with quiescent HSCs.qRTPCR validated the microarray data.Lentivirus-mediated suppression of Wnt5a expression in activated LX-2 resulted in significantly impaired proliferation,downregulated expressions of typeⅠcollagen and transforming growth factor-β1.Wnt5a was upregulated in the fibrotic liver of a CCl4-induced fibrosis rat model.CONCLUSION:Wnt5a is involved in the activation of HSCs,and it may serve as a novel therapeutic target in the treatment of liver fibrosis. 展开更多
关键词 Hepatic stellate cells WNT5A MICROARRAY Bioinformatics analyses Liver fibrosis
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Study on differential gene expression profile of serum exosomes in patients with acute cerebral infarction 被引量:6
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作者 TANG Rongmei CHEN Bowei +2 位作者 YI Jian LIU Baiyan LIN Huashan 《Digital Chinese Medicine》 2021年第4期305-315,共11页
Objective To analyze the differential gene expression profile of serum exosomes in patients with acute cerebral infarction(ACI)and clarify the changes in gene expression related to cerebral infarction injury and the p... Objective To analyze the differential gene expression profile of serum exosomes in patients with acute cerebral infarction(ACI)and clarify the changes in gene expression related to cerebral infarction injury and the potential serum markers.Methods Four patients with ACI and five healthy people were enrolled in the PhaseⅠstudy.After serum isolation from peripheral blood,exosomes were extracted with exosomes kits,highthroughput detection of m RNA was performed with gene chips,and differentially expressed m RNAs were screened.Gene Ontology(GO)functional analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis were performed simultaneously.Furthermore,real-time polymerase chain reaction(q RT-PCR)was used to verify the expression levels of the screened differential m RNAs in the serum exosomes collected in PhaseⅡfrom 32 patients each in the ACI case and normal control groups.Results In the PhaseⅠstudy,there were 248 differentially expressed m RNAs(fold change≥2.0,P<0.05)among five patients in the normal control group and four patients in the case group,of which the expression of 242 was upregulated and that of six was downregulated.The results of GO functional enrichment analysis mainly included behavior regulation,cell connection,and antioxidant activity.The results of KEGG pathway enrichment analysis mainly included ribosomes,proteasomes,oxytocin signaling pathways,and oxidative phosphorylation.After researching and screening based on relevant literature,it was found that among the genes with significant differential expression,H3 F3 B m RNA may be associated with and might play an important role in ACI.The q RT-PCR method was used to detect the H3 F3 B mRNA expression in serum exosomes of 32 patients each in the normal control and case groups in PhaseⅡ;the expression was significantly higher in serum exosomes of the case group than in those of the normal control group(P<0.001).H3 F3 B mRNA expression in serum exosomes of the case group positively correlated with age,the National Institutes of Health Stroke Scale(NIHSS)score,and the maximum infarct size(P<0.05).Conclusion ACI can lead to changes in the serum exosomes mRNA expression profile,which may be closely related to the occurrence,development,and prognosis of this condition.These findings will provide direction for research on the molecular mechanism,diagnostic markers,and therapeutic targets of ACI. 展开更多
关键词 Acute cerebral infarction(ACI) EXOSOMES MRNA Expression profile Gene chip H3F3B
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