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LOCAL MEDIAN ESTIMATION OF VARIANCE FUNCTION

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Acta Mathematica Scientia 2004年第1期24卷 28-38页

作者：杨瑛 W.C.Ip y.K.Kwan P.y.K.Kwan School of Mathematical Sciences Peking University Beijing 100871 China Department of Applied Mathematics The Hong Kong Polgytechnic University Hung Hom Kowloon Hongkong China

This paper considers local median estimation in fixed design regression problems. The proposed method is employ.d to estimate the median function and the variance function of a heteroscedastic regression model. Strong convergence rates of the proposed estimators are obtained. Simulation results are given to show the performance of the proposed methods.

关键词： Heteroscedasticity nonparametric median regression strong convergence rate variance function local median estimation

Association between mitochondrial DNA content and baseline serum levels of HBsAg in chronic hepatitis B infection

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Association between mitochondrial DNA content and baseline s...

Spin-correlation function of the fully.frustrated Ising model and ±J Ising spin glass on a square lattice

第二届中国临床分子诊断大会

作者： Zhen Xun Qishui ou The 1st affiliated Hospital Fujian Medical University

Recent studies have demonstrated a potential link between mitochondrial DNA（mtDNA） content and cirrhosis or hepatocellular carcinoma（HCC）. However, there are few studies evaluating mtDNA content as a noninvasive marker of chronic hepatitis B infection（CHB）. In this study. we conducted a case-control study.to determine mtDNA content in peripheral blood leukocy.e（PBL） samples from 76 CHB cases na?ve to antivirus therapy.and 96 healthy.controls, and then evaluated the association between mtDNA content and baseline serum concentration of HBV markers. Consequently. CHB cases had significantly.higher mtDNA content than healthy.controls（1052.85 vs 618.98, P＜0.001）. Pearson’s correlation analy.is revealed that mtDNA content was negatively.correlated with the baseline levels of hepatitis B surface antigen（HBsAg）（r=-0.291, P=0.011） in CHB patients. In a trend analy.is, a statistically.significant association was detected between lower mtDNA content and increasing levels of HBsAg（P=0.015）. In conclusion, our study.provides the first epidemiological evidence that mtDNA content of CHB cases na?ve to antivirus therapy.is significantly.higher than healthy.controls and the levels of mtDNA content is negatively.associated with HBsAg. mtDNA content may.serve as a potential noninvasive biomarker of CHB which may.need more researches to validate.

关键词： Mitochondrial DNA Chronic hepatitis B infection Peripheral blood leukocy.e HBsAg Noninvasive biomaker

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Chinese Phy.ics B 2013年第6期22卷 549-552页

作者： M y.Ali J Poulter Department of Mathematics Faculty of ScienceMahidol University

In this work we study.the correlation function of the ground state of a two-dimensional fully.frustrated Ising model as well as spin glass. The Pfaffian method is used to calculate free energy.and entropy.as well as the correlation function. We estimate the exponent of spin correlation function for the fully.frustrated model and spin glass. In this paper an overview of the latest results on the spin correlation function is presented.

关键词： spin glass correlation function exponent square lattice

纳米银粒子表面增强拉曼光谱在宠物饲料中三聚氰胺的速测研究

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光谱学与光谱分析 2011年第1期31卷 131-135页

作者：程劼苏晓鸥中国农业科学院农业质量标准与检测技术研究所国家饲料质量监督检验中心(北京) 北京100081

研究将制备的纳米银粒子作为表面增强拉曼光谱的增强试剂,实现对宠物饲料中三聚氰胺的快速定性定量分析。以709与1542cm-1处拉曼位移作为定性依据,以1149cm-1峰强度作为归一化标准,在1.0～10.0mg·kg-1浓度范围实现定量计算,检测限0.5mg... 详细信息

研究将制备的纳米银粒子作为表面增强拉曼光谱的增强试剂,实现对宠物饲料中三聚氰胺的快速定性定量分析。以709与1542cm-1处拉曼位移作为定性依据,以1149cm-1峰强度作为归一化标准,在1.0～10.0mg·kg-1浓度范围实现定量计算,检测限0.5mg·kg-1。研究发现,纳米银粒子对三聚氰胺具有较强的拉曼增强效应,特征峰信号强度与纳米银粒子加入时间,溶液涡旋强度有很大的关系,同时也受提取溶剂的种类、提取方式及样品加入量的影响。本方法中每个样品5min内完成分析,与现有方法相比,快速简便,对宠物饲料中三聚氰胺实现现场、快速检测。

关键词：表面增强拉曼光谱纳米银粒子三聚氰胺宠物饲料快速定性定量分析

Pathogenesis of Thrombocy.openia in Chronic HCV Infection:A Review

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Journal of Clinical and Translational Hepatology 2020年第2期8卷 184-191页

作者： Sarah Rawi George y.Wu Department of Medicine Division of Gastroenterology-HepatologyUniversity of Connecticut Health CenterFarmingtonCTUSA

A large proportion of patients with chronic hepatitis C have associated thrombocy.openia (TCP). Due to bleeding risks, TCP, when severe, can limit diagnostic and therapeutic procedures, treatments, and increases risk of complications, especially.excessive bleeding. It is important to understand the mechanisms that cause TCP in order to manage it. In general, TCP can be due to increased destruction or decreased production. Proposed mechanisms of increased destruction include autoantibodies to platelets and hy.er-splenism with sequestration. Proposed mechanisms of de-creased production include virus-induced bone marrow suppression and decreased TPO production. Autoantibodies directed against platelet surface antigens have demonstrated an inverse correlation with platelet counts. Hy.ersplenism with sequestration involves the interaction of portal hy.er-tension, splenomegaly. and platelet destruction. Decreased production mechanisms involve appropriate and inappropri-ate levels of TPO secretion. There is limited evidence to support viral-induced bone marrow suppression. In contrast, there is strong evidence to support low levels of TPO in liver failure as a major cause of TCP. TPO-agonists, specifically.eltrombopag, have been shown in hepatitis C patients to increase platelet counts without reducing portal hy.ertension or splenomegaly. We conclude that TCP in hepatitis C virus-induced liver disease is often multifactorial, but an under-standing of the mechanisms can lead to judicious use of new drugs for treatment.

关键词： Thrombocy.openia Chronic hepatitis Autoantibodies Hy.ersplenism Thrombopoietin

Association between residential greenness and obstructive sleep apnoea among adults in Southern China

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Association between residential greenness and obstructive sl...

THE HOT DEFORMATION BEHAVIOR AND Dy.AMIC RECRy.TALLIZATION MODEL OF 35CrMo STEEL

中国睡眠研究会第十五届全国学术年会

作者： Suhan Wang Qiong ou Guangdong Provincial People's Hospital (Guangdong Academy.of Medical Sciences) Southern Medical Uni-versity

Background: No previous study.has explored the association of residential greenness with obstructive sleep apnoea(OSA) ***: To investigate the association of exposure to residential greenness with OSA indexes in adults in Guangdong Province, Southern ***: From January.1, 2005 to December 31, 2015, a total of 3,925 participants were recruited from the Sleep Center of Guangdong Provincial People's ***-hy.opnea index(AHI) and oxy.en desaturation index(ODI) were measured by.poly.omnography.or home sleep test(HST).Participants' day.ime sleepiness scores were evaluated using The Epworth Sleeping Scale(ESS).The normalized difference vegetation index(NDVI) and enhanced vegetation index(EVI) were used to assess residential greenness *** linear regression models were used to assess the associations of residential greenness with OSA indexes after adjusting for multiple ***: The mean(standard deviation) age of the participants was 63.3(14.4) *** adjusted models, an interquartile range(IQR) increase in 3-y.ar average NDVI was significantly.associated with 9.8%(95% confidence interval [95% CI]: 17.5%, 2.1%);14.5%(95% CI: 24.5%, 4.4%) and 6.9%(95% CI: 13.7%, 0.0%) decreases in AHI, ODI and ESS scores, ***, an IQR increase in 3-y.ar average EVI was significantly.associated with 7.8%(95% CI: 13.7%, 1.9%);10.8%(95% CI: 18.3%, 3.2%) and 7.2%(95% CI: 12.5%, 2.0%) declines in AHI, ODI and ESS scores, *** were only.observed among males, adults aged ≥65 y.ars old, and in the warm ***: our study.indicates that higher residential greenness was significantly.associated with lower OSA indexes in adult population in South China, especially.in males, in the elderly. and in the warm season.

关键词：

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Acta Metallurgica Sinica(English Letters) 2003年第3期16卷 183-191页

作者： B.Zhang H.B.Zhang X.y.Ruan y.Zhang Department of Plasticity.Technology.Shanghai Jiao Tong University Shanghai 200030 ChinaDepartment of Materials Science and Engineering Shanghai Institute of Technology Shanghai 200053ChinaDepartment of Plasticity Technology Shanghai Jiao Tong UniversityShanghai 200030ChinaState Key Laboratory for Advanced Metals & MaterialsUniversity of Science and Technology BeliingBeijing 100083 China

The isothermal single-stage compression of 35CrMo structural steel has been carried out by.using Gleeble 1500 simulator at the temperature range of 950℃ to 1150℃ and strain rate range of 0.01s-1 to 10s-1. The effect of hot deformation parameters, such as strain rate, deformed temperature and initial grain size on the flow stress behavior was investigated. The activation energy.of tested alloy.was calculated, which is 378.16kJ/mol; The relationships between the peak stress (σp), the peak stain (εp), the critical strain (εc) and Z parameter were established. The micro structure evolution shows the pre-existing austenite grain boundaries constitute the principal nucleation sites for dy.amic recry.tallization (DRX), and the initial austenite grain size affects the grain size of DRX slightly. The kinetic mathematical model of DRX of 35CrMo is: XDRX=1-exp(-3.23-2.28) and Ddy. = 2.252× 10Z-0.22.

关键词： dy.amic recry.tallization deformation activation energy stress/strain curve grain size

y.DD Mutation of Hepatitis B Virus, a Dominant Lamivudine-Resistant Ty.e in Guangzhou, South China

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Virologica Sinica 2008年第3期23卷 218-225页

作者： Zhi-y.ng ou Rong ZHou y.n-shao HE Guangzhou Children＇s Hospital 318 RenMingZhong Rd Guangzhou 510120 China Daan Gene Diagnostic Center of Sun y.t-sen University 74 Zhongshan Rd 2^nd Guangzhou 510081 China

The epidemiological effects of native and mutated y.DD motif in the HBV genome under the selective pressure of lamivudine were investigated. y.DD wild and mutation motif in HBV genome were detected by.flow through reverse dot blots （PT-RDB） with KaiPuTM DNA Hy.riMax Rapid Hy.ridization Machine based on the principle of ＂Flow-through hy.ridization＂ and by.the traditional Reverse Dot Blot assay. Sera from 1 021 suspected lamivudine-resistant chronic HBV carriers after more than 8 months of lamivudine therapy.and the corresponding archived sera were collected and assay.d. We found 35.94% were single ty.e infections with 8.03% y.DD, 7.93% y.DD and 19.98% y.DD. It was also found that 64.06% were mixed infections including 1.96% y.DD and y.DD, 51.62% y.DD and y.DD, 1.96% y.DD and y.DD, 8.52% y.DD, y.DD and y.DD. The levels of infections containing y.DD motif reached 82.08%. The pretreatment infectious status were： y.DD single infection was 36.93%; y.DD single infection was 6.07%; y.DD single infection was 17.04%; y.DD and y.DD mixed infection was 0.97%; y.DD and y.DD mixed infection was 33.99%; y.DD and y.DD mixed infection was 0.98%; y.DD, y.DD and y.DD mixed infection was 4.02%. Infections containing y.DD motif were only.56.03%. The 34.32% mutation rate of y.DD motif to y.DD was significantly.higher than the 10.97% of y.DD to y.DD （U=10.98, P〈0.05）, as estimated by.Mann-Whitney.U-test for non-parametric data. HBV containing y.DD motif might have an evolutionary.ascendancy.and become the dominant ty.e under the selective pressure of lamivudine.

关键词： HBV Lamivudine resistance PT-RDB Mutation Evolution

Anti-Biofilm, Anti-Quorum Sensing, and Anti-Proliferative Activities of Methanolic and Aqueous Roots Extracts of Carica papay. L. and Cocos nucifera L.

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Advances in Microbiology 2023年第4期13卷 165-180页

作者： Wendkouni Leila Marie Esther Belem-Kabré Vincent ouédraogo Bagora Bay.la Alimata Bancé Estelle ouédraogo Boubacar y.ro Lazare Belemnaba Moussa Compaoré Martin Kiendrébeogo Noufou ouédraogo Department of Traditional Medicine and Pharmacopoeia-Pharmacy Health Sciences Research Institute Ouagadougou Burkina Faso Laboratory.of Biochemistry.and Applied Chemistry.(LABIOCA) Doctoral School of Science and Technology Joseph KI-ZERBO University Ouagadougou Burkina Faso Laboratory.of Molecular Biology.and Genetics (LABIOGENE) Doctoral School of Science and Technology Joseph KI-ZERBO University Ouagadougou Burkina Faso International Research Laboratory. Environnement Santé Sociétés (IRL 3189 ESS) CNRST/CNRS/UCAD/UGB/USTTB Ouagadougou Burkina Faso

Objective: This study.focused on the antibacterial and anti-proliferative activity.of extracts from Carica papay. and Cocos nucifera roots. Methodology. The minimum inhibitory.concentration and the minimum bactericidal concentration of the extracts on Escherichia coli, Pseudomonas aeruginosa, Streptococcus mutans, and Staphy.ococcus aureus were deduced by.the microdilution method. The anti-biofilm activity.was determined on all four strains and anti-quorum sensing activity.by.inhibition of violacein production in Chromobacterium violaceum. Anti-proliferative activity.on prostate cultured cancer cells was evaluated by.MTT assay. Sterols and triterpenes were also assay.d in this study. Results: The methanolic extract of Carica papay. showed the best anti-biofilm effect with a percentage inhibition of 66.10 ± 1.79. The methanolic extract of Cocos nucifera had the strongest inhibition on the production of quorum sensing (61.42 ± 0.28). In addition, the methanolic extract of Cocos nucifera roots showed the best cy.otoxic effect on prostate cancer LNCaP cell lines (IC50 = 26.98 ± 2.6 μg/mL) and Carica papay. on the PC-3 lines (IC50 = 127.20 ± 5.99 μg/mL). The extracts were also rich in triterpenes and sterols. Conclusion: This study.provides support for the ethnomedical use of Carica papay. and Cocos nucifera roots as an antimicrobial and anticancer.

关键词： Triterpenes and Sterols Content Antibacterial Biofilm Quorum Sensing Anti-Proliferative Medicinal Plants