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Quantification of Panax notoginseng saponins metabolites in rat plasma with in vivo gut microbiota-mediated biotransformation by HPLC-MS/MS

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Chinese Journal of Natural Medicines 2019年第3期17卷 231-240页

作者： GUO Yin-Ping CHEN Man-Yun SHAO Li ZHANG Wei RAO Tai ZHOU Hong-Hao HUANG Wei-Hua Department of Clinical Pharmacology Xiangya Hospital Central South University Institute of Clinical Pharmacology Hunan Key Laboratory of Pharmacogenetics Central South University Department of Pharmacognosy School of Pharmacy Hunan University of Chinese Medicine

Panax notoginseng saponins(PNS) are the major components of Panax notoginseng, with multiple pharmacological activities but poor oral bioavailability. PNS could be metabolized by gut microbiota in vitro, while the exact role of gut microbiota of PNS metabolism in vivo remains poorly understood. In this study, pseudo germ-free rat models were constructed by using broad-spectrum antibiotics to validate the gut microbiota-mediated transformation of PNS in vivo. Moreover, a high performance liquid chromatography-electrospray ionization tandem mass spectrometry(HPLC-ESI-MS/MS) was developed for quantitative analysis of four metabolites of PNS, including ginsenoside F1(GF1), ginsenoside Rh2(GRh2), ginsenoside compound k(GCk) and protopanaxatriol(PPT). The results showed that the four metabolites could be detected in the control rat plasma, while they could not be determined in pseudo germ-free rat plasma. The results implied that PNS could not be biotransformed effectively when gut microbiota was disrupted. In conclusion, gut microbiota plays an important role in biotransformation of PNS into metabolites in vivo.

关键词： Panax notoginseng Gut microbiota HPLC-MS/MS Saponins Ginsenoside compound k Protopanaxatriol

Synergistic effect of Si and K in improving the growth,ion distribution and partitioning of Lolium perenne L.under saline-alkali stress

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Journal of Integrative Agriculture 2021年第6期20卷 1660-1673页

作者： FAN Yuan SHEN Wu-yan Pino VANESSA CHENG Fang-qin Institute of Resources and Environmental Engineering Shanxi University/State Environmental Protection Key Laboratory of Efficient Utilization Technology of Coal Waste ResourcesTaiyuan 030006P.R.China Sydney Institute of Agriculture School of Life and Environmental SciencesThe University of SydneyNSW 2006Australia

The application of Si or K has proven to be beneficial for the growth of plants under saline-alkali stress. However, the synergistic effect of Si and K in improving the growth, ion distribution, and partitioning in Lolium perenne L. under saline-alkali stress remains unclear. In this study, the growth characteristics and ion-selective absorption of ryegrass(Lolium perenne L.) exposed to different levels of saline-alkali stress were evaluated. The growth parameters of ryegrass were significantly improved when Si was applied by itself or coupled with K under low saline-alkali stress. Under a high saline-alkali level, only simultaneous application of Si and K could significantly improve the growth of ryegrass. When Si and K were applied together, the k^(+)/Na^(+) and Ca^(2+)/Na^(+) ratios in root, stem, and leaf of ryegrass were maximally improved as compared to the individual treatments and control. The k^(+) and Ca^(2+) concentrations in the vacuole, cell wall, and organelle of leaf were increased dramatically. This improvement was due to the ability of applied ions to compete with Na^(+), allowing the plant to maintain osmotic potential and leaf water content. The concentration of Na^(+) was significantly reduced when Si and K were applied and mainly concentrated in the soluble fraction and cell wall. The Si concentration in ryegrass increased markedly by the combined application of Si and k, and most of it was accumulated in the cell wall and soluble fraction, which could help in chlorophyll synthesis, reduce membrane injury, and increase water absorption under saline-alkali stress. This study emphasized the advantage of Si and/or K on the growth of plants under different saline-alkaline levels and provided a guide for the production of Si-K fertilizer and its application in saline-alkali soil.

关键词： saline-alkali stress Si k ryegrass plants k+/Na+ compartmentation

Diagnostic value of gamma-glutamyltransferase/aspartate aminotransferase ratio, protein induced by vitamin K absence or antagonist II, and alpha-fetoprotein in hepatitis B virus-related hepatocellular carcinoma

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World Journal of Gastroenterology 2019年第36期25卷 5515-5529页

作者： Qiang Wang Qi Chen Xia Zhang Xiao-Lan Lu Qin Du Tao Zhu Guo-Yuan Zhang Dong-Sheng Wang Qu-Ming Fan Department of Laboratory Medicine Affiliated Hospital of North Sichuan Medical College Nanchong 637000 Sichuan Province China Faculty of Laboratory Medicine Center for Translational Medicine North Sichuan Medical College Nanchong 637000 Sichuan Province China Department of Laboratory Medicine Affiliated Sichuan Ba-Yi Rehabilitation Center of Chengdu University of TCM Chengdu 610000 Sichuan Province China Department of Laboratory Medicine of the Ninth People’s Hospital of Chongqing Chongqing 400700 China Department of Preventive Medicine North Sichuan Medical College Nanchong 637000 Sichuan Province China

BACkGROUND Researchers have investigated the diagnostic value of protein induced by vitamin K absence or antagonist II (PIVkA-II) and alpha-fetoprotein (AFP) in hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC), and obtained abundant clinical diagnostic data. However, PIVkA-II and AFP have unsatisfactory specificity and sensitivity in the diagnosis of early-stage HBV-related HCC. Gamma-glutamyltransferase (γ-GT) and aspartate aminotransferase (AST) are common biomarkers for evaluating liver function, and we hypothesized that the γ-GT/AST ratio in combination with PIVkA-II and AFP would improve the diagnosis of early-stage HBV-related HCC. AIM To evaluate the diagnostic value of γ-GT/AST ratio alone or in combination with PIVkA-II and AFP in HBV-related HCC. METHODS Serum levels of γ-GT, AST, PIVkA-II, and AFP were detected and analysed in 176 patients with HBV-related HCC and in 359 patients with chronic hepatitis B. According to tumour size and serum level of HBV DNA, HBV-related HCC patients were divided into the following categories: Early-stage HCC patients, HCC patients, HBV DNA positive (HBV DNA+) HCC patients, and HBV DNA negative (HBV DNA-) HCC patients. Receiver-operating characteristic (ROC) curves were used to analyse and compare the diagnostic value of the single and combined detection of various biomarkers in different types of HBV-related HCC. RESULTS Tumour size was positively correlated with serum levels of PIVkA-II and AFP in HCC patients (r = 0.529, aP 0.05). When PIVkA-II was combined with the γ-GT/AST ratio in the diagnosis of earlystage HCC, HCC, and H

关键词： Gamma-glutamyltransferase Aspartate aminotransferase Protein induced by vitamin k absence or antagonist II Alpha-fetoprotein Hepatitis B virus Hepatocellular carcinoma

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改进聚类的深度神经网络压缩实现方法

控制理论与应用 2019年第7期36卷 1130-1136页

作者：刘涵王宇马琰西安理工大学自动化与信息工程学院

深度神经网络通常是过参数化的,并且深度学习模型存在严重冗余,这导致了计算和存储的巨大浪费.针对这个问题,本文提出了一种基于改进聚类的方法来对深度神经网络进行压缩.首先通过剪枝策略对正常训练后的网络进行修剪,然后通过k-Means+... 详细信息

深度神经网络通常是过参数化的,并且深度学习模型存在严重冗余,这导致了计算和存储的巨大浪费.针对这个问题,本文提出了一种基于改进聚类的方法来对深度神经网络进行压缩.首先通过剪枝策略对正常训练后的网络进行修剪,然后通过k-Means++聚类得到每层权重的聚类中心从而实现权值共享,最后进行各层权重的量化.本文在LeNet、AlexNet和VGG-16上分别进行了实验,提出的方法最终将深度神经网络整体压缩了30到40倍,并且没有精度损失.实验结果表明通过基于改进聚类的压缩方法,深度神经网络在不损失精度的条件下实现了有效压缩,这使得深度网络在移动端的部署成为了可能.

关键词：深度神经网络剪枝 k Means++聚类深度网络压缩

林下三七k/H反向转运体PnkEA4的克隆及表达分析

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分子植物育种 2022年

作者：张馨艺赵小艳王澍何霞红西南林业大学西南山地森林资源保育与利用教育部重点实验室西南林业大学园林园艺学院国家林业和草原局西南风景园林工程技术研究中心

为了研究k/H反向转运体(k/Hexchanger， kEA)在林下三七(Panax notoginseng) k运输中所发挥的作用。本实验从林下三七中克隆出一个k/H反向转运体基因，命名为PnkEA4 (基因登录号: OP375109)。结果表明，PnkEA4基因开放阅读框为1 803 bp... 详细信息

为了研究k/H反向转运体(k/Hexchanger， kEA)在林下三七(Panax notoginseng) k运输中所发挥的作用。本实验从林下三七中克隆出一个k/H反向转运体基因，命名为PnkEA4 (基因登录号: OP375109)。结果表明，PnkEA4基因开放阅读框为1 803 bp，编码了600个氨基酸。根据生物信息学的分析结果发现，PnkEA4蛋白具有11个跨膜结构域，其中具有典型的k/H交换结构域，且定位于细胞质膜上。同时，PnkEA4蛋白与胡萝卜kEA4蛋白具有高度的同源性。实时荧光定量结果显示，PnkEA4在林下三七不同组织呈非诱导表达(茎>根>叶)。此外，在高钾(25 mmol/L k)胁迫下，PnkEA4在林下三七不同组织中的表达量不同，表现为茎>叶>根的表达模式。与对照组相比，PnkEA4在根、茎中下调表达，而叶片中上调表达。

关键词：林下三七(Panax notoginseng) k /H 反向转运体(k /H exchanger， kEA) PnkEA4 克隆及表达分析高钾胁迫

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空间液氦温区J-T节流制冷机节流微孔实验

科学通报 2018年第18期63卷 1839-1846页

作者：马跃学王娟刘彦杰李建国梁惊涛中国科学院理化技术研究所北京100190

液氦温区节流制冷机在空间探测中获得了广泛的应用,基于本实验室研制的多级高频脉冲管预冷节流循环的复合式制冷机,针对节流微孔对节流制冷机性能的影响进行分析和实验.研究发现,节流微孔的尺寸不仅影响节流制冷机的流量,对节流制冷效... 详细信息

液氦温区节流制冷机在空间探测中获得了广泛的应用,基于本实验室研制的多级高频脉冲管预冷节流循环的复合式制冷机,针对节流微孔对节流制冷机性能的影响进行分析和实验.研究发现,节流微孔的尺寸不仅影响节流制冷机的流量,对节流制冷效果也有着重要影响.通过实验对不同孔径微孔进行了研究,获得了最佳微孔尺寸.此外,对节流前高压对节流制冷机流量、制冷机和最低无负荷温度的影响进行了分析和实验研究.基于此,采用三级无油线性压缩机驱动节流循环,测试了闭式循环节流制冷机的性能,在4.48 k获得了81.5 m W的制冷量.

关键词：空间 4.5 k J-T制冷机线性压缩机节流微孔

两种固结状态下软土的三轴不排水剪切模量非线性及对比

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岩土工程学报 2021年第S2期43卷 64-67页

作者：高彦斌罗文康骆佳樑钱谨伟张和森同济大学土木工程学院地下建筑与工程系

原位软土通常是具有初始各向异性的k;固结土,室内三轴试验通常使用各向等压固结的重塑土。通过对由上海软黏土制成的原状与重塑土样进行k;固结与各向等压固结土的不排水剪切试验（ICUC、ACUC、ACUE三种试验）,对比两种固结方式下归一化... 详细信息

原位软土通常是具有初始各向异性的k;固结土,室内三轴试验通常使用各向等压固结的重塑土。通过对由上海软黏土制成的原状与重塑土样进行k;固结与各向等压固结土的不排水剪切试验（ICUC、ACUC、ACUE三种试验）,对比两种固结方式下归一化强度c;/σ’;、归一化模量Eu50/σ’;及归一化模量E;/E;–ε;的非线性特性。研究结果表明,两种固结方式下土体的应力–应变曲线具有明显的非线性特点,在强度发挥、归一化强度上存在差异;以E;作为归一化因子给出的归一化磨料E;/E;非线性归一化效果很好,原状土样和重塑土样的归一化模量曲线几乎是相同的。

关键词：软黏土非线性变形各向异性割线模量 k 与各向等压

Atrial fibrillation in the elderly

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Journal of Geriatric Cardiology 2019年第1期16卷 49-53页

作者： Pablo Díez-Villanueva Fernando Alfonso Department of Cardiology Hospital Universitario de la Princesa

Atrial fibrillation(AF)is the most common arrhythmia in elderly population,with age being one of the most important factors involved in its pathogenesis.Conduction disturbances may be present on the surface electrocardiogram before AF onset in some patients.Once this arrhythmia is diagnosed,antithrombotic therapy is mandatory in most cases,as this is the only treatment that has demonstrated to improve survival.Age increases both the risK of thromboembolic and bleeding complications,while benefits from anticoagulant therapy outweigh that from bleeding in most scenarios,also in very elderly patients.However,elderly patients with AF are often undertreated.Non-vitamin K antagonist oral anticoagulants have emerged as an alternative to vitamin K antagonists,with significant less adverse events and better profile in terms of efficacy and safety.Other conditions related to age should be carefully evaluated in these patients(including frailty,comorbidity and polypharmacy)to ensure an individualized clinical and therapeutic approach.

关键词： Atrial fibrillation Antithrombotic therapy Frailty Non-vitamin k antagonist oral anticoagulants The elderly

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移动k-支配最近邻查询验证研究

计算机学报 2018年第8期41卷 1780-1797页

作者：崔宁宁杨晓春王斌朱怀杰东北大学计算机科学与工程学院沈阳110819

现有的基于位置服务(Location-Based Services,LBS)查询结果都是直接基于LBS服务商返回的结果.但LBS服务提供商是易被勾结的和不受信任的,所以给用户提供一种可信查询服务是非常必要的.因此,研究可信环境下的空间数据库查询具有重要意义... 详细信息

现有的基于位置服务(Location-Based Services,LBS)查询结果都是直接基于LBS服务商返回的结果.但LBS服务提供商是易被勾结的和不受信任的,所以给用户提供一种可信查询服务是非常必要的.因此,研究可信环境下的空间数据库查询具有重要意义.该文关注在移动过程中的k-支配最近邻查询和验证,该查询本质上是k-最近邻(k-Nearest Neighbor,kNN)和轮廓(Skyline)查询的结合.其目标是对于一个给定的查询q,返回在空间属性和非空间属性上不受支配的且距离最接近查询点q的k个点.为了有效解决移动k-支配最近邻查询验证问题,该文提出了一种新的安全区域(Safe Region,SR)和验证数据结构(Authenticated Data Structure,ADS)Merkle Verifiable Voronoi R-tree(MV2 R-tree)用于产生查询结果和验证对象(Verification Object,VO).在此基础上,该文基于比较分析提出了Rectangle-based验证策略用于验证查询结果和安全区域.最后,通过大量的实验验证了提出的方法的有效性.

关键词：基于位置服务可信查询 k -支配安全区域验证对象验证数据结构