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Comparison of magnetic properties of DNA-cetyltrimethyl ammonium complex with those of natural DNA

Science China Chemistry 2012年第5期55卷 814-821页

作者： KWON Young-Wan CHOI Dong Hoon jin Jung-Il LEE Chang Hoon koh Eui Kwan GROTE James G. Department of Chemistry Korea University Seoul 136-701 Korea Department of Polymer Science & Engineering Chosun University Gwangju 501-759 Korea Korea Basic Science Institute-Seoul Branch Korea University Seoul 136-701 Korea US Air Force Research Laboratory Materials and Manufacturing Directorate AFRL/MLPS Wright-Patterson Air Force Base Ohio USA

We prepared the DNA-cetyltrimethyl ammonium complex, as well as the same complex intercalated with stable organic free radicals, and studied their magnetic properties by electron magnetic resonance (EMR) spectroscopy and by measuring the magnetization on a superconducting quantum interference device (SQUID). The UV-vis and CD spectra of DNA-quaternary alkyl ammonium complex (DNA--Q+) in organic solvent clearly demonstrated that it retained the double helical B-form conformation. The interhelical spacing of double strand DNA (dsDNA) increased when the counter ions (Na+) of phosphate groups of the natural DNA were replaced with the long alkyl quaternary ammonium groups. The inter-helical distance of DNA-cetyltrimethyl ammonium (CTMA) was 39.1  as confirmed by X-ray diffractometry. In general, the magnetization of the DNA-CTMA complex solid was found to be significantly lower than that of natural DNA. Moreover, intercalation of the complex with stable organic free radicals did not improve magnetization, which again was in marked contrast to natural DNA. EMR spectroscopic behavior of the complex in the solid state also was quite different from that of natural DNA: The unique broad EMR signal of natural DNA in the low field region with g-value greater than 10 disappeared in the DNA-CTMA complex.

关键词： natural DNA DNA-CTMA DNA-CTMA-PTMI magnetic property electron magnetic resonance (EMR) superconducting quantum interference device (SQUID)

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Pravastatin activates PPARα/PPARγexpression in the liver and gallbladder epithelium of hamsters

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Hepatobiliary & Pancreatic Diseases International 2011年第2期10卷 185-190页

作者： Seok Ho Dong jin Lee Dong Hee koh Min Ho Choi Hyun Joo Jang Sea Hyub Kae Division of Gastroenterology Department of Internal MedicineKyung Hee University College of Medicine Division of Gastroenterology Department of Internal MedicineHallym University College of Medicine

BACKGROUND:Our earlier study with cultured gallbladder epithelial cells demonstrated that statins(HMG-CoA reductase inhibitors)activate the expression of PPARαand PPARγ, consequently blocking the production of pro-inflmmatory *** present study used hamsters to investigate the effects of pavastatin on PPARα/PPARγexpression in the liver and gallbladder epithelium,and to determine whether pravastatin suppresses cholesterol crystal formation in the gallbladder. METHODS:A total of 40 Golden Syrian male hamsters(4 weeks old)were randomly assigned to four groups(basal diet control; basal diet+pavastatin;high cholesterol diet;high cholesterol diet+pravastatin).All hamsters were 11 weeks old at the end of the *** liver,gallbladder and bile were harvested. Immunohistochemical staining and Western blotting for PPARαand PPARγwere performed in the liver and gallbladder. A drop of fresh bile was examined for cholesterol crystals under a microscope. RESULTS:In the gallbladder and liver of the hamsters, pravastatin activated the PPARαand PPARγexpression of gallbladder epithelial cells and hepatocytes,and particularly the response of PPARγwas much stronger than that of PPARα. Pravastatin suppressed the formation of cholesterol gallstones or crystals in the gallbladder. CONCLUSION:Pravastatin is an effective medication to activate PPARs(especially PPARγ)in the liver and the gallbladder epithelium of hamsters,and contributes to the prevention of gallstone formation.

关键词： pravastatin PPARα PPARγ hamster gallstone

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An Efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron Nitride Nanotubes

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Nano-Micro Letters 2025年第1期17卷 548-558页

作者： Ying Wang Kai Zhang Liping Ding Liyun Wu Songfeng E Qian He Nanyang Wang Hui Zuo Zhengyang Zhou Feng Ding Yue Hu jin Zhang Yagang Yao National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093People’s Republic of China School of Electronic Information and Artificial Intelligence Shaanxi University of Science&TechnologyXian 710000People’s Republic of China College of Bioresources Chemical and Materials Engineering Shaanxi University of Science&TechnologyXian 710000People’s Republic of China Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000People’s Republic of China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518000People’s Republic of China College of Chemical and Molecular Engineering Peking UniversityBeijing 100871People’s Republic of China

Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their *** primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid *** this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B *** approach can be adopted to form various low-melting-point AM–Mg–B–O growth *** growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN *** findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNTs.

关键词： Boron nitride nanotubes Low-temperature Boron activation Density functional theory

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“寒门贵子”是“补偿”还是“选拔”出来的?——对两所精英大学2018—2023年高校专项计划招生的追踪研究

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华东师范大学学报（教育科学版） 2025年第1期43卷 113-126页

作者：金文旺柳夕浪北京师范大学中国教育与社会发展研究院北京100875 山东师范大学教育学部济南250014

高校专项计划是我国促进高质量教育公平、破解农村学生上好大学难而出台的一项入学机会补偿政策。综合运用描述性统计方法,本研究对两所精英大学2018—2023年间高校专项计划的选录情况进行了持续追踪研究。从初审、降分、录取人数的总... 详细信息

高校专项计划是我国促进高质量教育公平、破解农村学生上好大学难而出台的一项入学机会补偿政策。综合运用描述性统计方法,本研究对两所精英大学2018—2023年间高校专项计划的选录情况进行了持续追踪研究。从初审、降分、录取人数的总体规模及变化趋势看,近几年高校专项计划政策力度不断加大,越来越多的寒门子弟进入精英高校。同时,精英大学高校专项计划实际招生呈现“补偿不均,选拔有余”的鲜明特点,经济欠发达、教育发展水平薄弱省域的农村学生和学校在该计划中并未获得更多优质高校入学机会的补偿,一个重要原因在于他们在高校自主选拔和高考选拔中处于劣势。为此,应调整高校专项计划招生办法及相关政策,确立“补偿为主,兼顾选拔”的价值导向并切实付诸实践,推进“实质的公平”。

关键词：高校专项计划补偿选拔教育公平精英大学

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乒乓球运动者正手弧圈球不同触地模式的下肢生物力学变化

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中国组织工程研究 2025年第14期29卷 2995-3001页

作者：晋鹏飞任杰上海体育大学中国乒乓球学院上海市200438

背景:探讨基于步法的足部触地模式对乒乓球运动中下肢关节运动特征的影响,可为指导下肢训练提供科学依据。目的:对比乒乓球运动中不同触地模式下的运动学和动力学差异。方法:使用动作捕捉和三维测力台同步采集17名专业乒乓球运动员在正... 详细信息

背景:探讨基于步法的足部触地模式对乒乓球运动中下肢关节运动特征的影响,可为指导下肢训练提供科学依据。目的:对比乒乓球运动中不同触地模式下的运动学和动力学差异。方法:使用动作捕捉和三维测力台同步采集17名专业乒乓球运动员在正常触地和全脚掌触地模式下优势侧下肢的运动学和动力学数据。配对样本t检验用于分析关节角度、地面反作用力、关节反作用力和关节力矩等离散指标的统计学差异;统计参数映射用于分析足底压力中心移动轨迹和膝关节力矩等时间序列数据的统计学差异。结果与结论:①正常触地模式下的膝关节内翻、侧向地面反作用力、膝关节垂直反作用力和伸膝力矩峰值显著高于全脚掌触地模式;②在足底压力中心移动距离中的89%-91%运动阶段,正常触地模式压力中心显著远于全脚掌触地模式;③在X轴力矩曲线中的23%-38%运动阶段,正常触地模式的伸膝力矩显著大于全脚掌触地模式;④在Y轴力矩曲线的8%-18%运动阶段,全脚掌触地模式显著大于正常触地模式。通过对比不同触地模式的下肢生物力学特征值和统计参数映射分析结果,认为全脚掌触地模式可能是影响乒乓球运动表现的重要因素。乒乓球运动中需要针对性地对触地模式进行调整和练习,避免使用全脚掌触地模式,提升乒乓球运动者下肢运动能力。

关键词：触地模式乒乓球运动学动力学运动表现

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基于REOF的不同量级降雨侵蚀力时空变化——以重庆市为例

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西南大学学报（自然科学版） 2025年第1期47卷 163-177页

作者：靳军英王林金铁生张卫华西南大学资源环境学院重庆400715

研究重庆市不同地理分区内各量级降雨侵蚀力的时空变化特征,为该地区进行更加精准的区域性水土流失防治工作提供理论依据。选取1981-2020年重庆市31个站点逐日降雨数据,利用旋转经验正交函数(Rotated Empirical Orthogonal Function,RE... 详细信息

研究重庆市不同地理分区内各量级降雨侵蚀力的时空变化特征,为该地区进行更加精准的区域性水土流失防治工作提供理论依据。选取1981-2020年重庆市31个站点逐日降雨数据,利用旋转经验正交函数(Rotated Empirical Orthogonal Function,REOF)对降雨侵蚀力进行地理分区,并结合R/S、5年滑动平均、Mann-Kendall检验等方法,分析各分区不同量级降雨侵蚀力时空变化。结果表明:①重庆市降雨侵蚀力可分为6个地理区域(Ⅰ-Ⅵ区);②重庆市多年平均降雨侵蚀力为5784.04 MJ·mm/(hm^(2)·h·a),不同降雨侵蚀力从大到小依次为:大雨、暴雨、中雨、大暴雨;③大雨侵蚀力在Ⅰ-Ⅲ区和Ⅴ-Ⅵ区占主导优势,暴雨侵蚀力在Ⅳ区占主导优势。各分区中,中雨、大雨及暴雨侵蚀力主要集中在5-9月,大暴雨侵蚀力集中在6-8月;④各区不同量级降雨侵蚀力年际变化从小到大依次为:中雨、大雨、暴雨、大暴雨;同一量级降雨侵蚀力的整体变化趋势均不显著;Hurst指数表明,中雨侵蚀力在Ⅰ和Ⅴ区、大雨侵蚀力在Ⅱ和Ⅴ区、大暴雨侵蚀力在Ⅰ和Ⅲ区呈强持续上升趋势;⑤中雨、大雨及大暴雨侵蚀力在渝东南、渝东北占主导优势,暴雨侵蚀力在渝西以及重庆中部占主导优势,且Ⅰ区酉阳和秀山、Ⅱ区开州、Ⅲ区北碚和铜梁、Ⅳ区璧山和永川、Ⅴ区巫溪和云阳及Ⅵ区忠县是不同量级降雨侵蚀力的高峰中心。通过对重庆各分区不同量级降雨侵蚀力的分析,明确了可能引起土壤侵蚀的主要雨型、高发时期和潜在风险较高的地区,可为区域水土流失动态监测和水土保持措施的合理制定提供参考。

关键词：降雨侵蚀力时空变化旋转经验正交分解法 MK非参数趋势检验 R/S分析法

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Restenosis of a drug eluting stent on the previous bioresorbable vascular scaffold successfully treated with a drug-coated balloon: A case report

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World Journal of Clinical Cases 2021年第3期9卷 758-763页

作者： Hyun Gyung Jang Kyehwan Kim Hyun Woong Park jin-Sin koh Young-Hoon Jeong Jeong Rang Park MinGyu Kang Department of Internal Medicine Gyeongsang National University School of Medicine and Gyeongsang National University HospitalJinjuSouth Korea Department of Internal Medicine Gyeongsang National University School of Medicine and Gyeongsang National University Changwon HospitalChangwonSouth Korea

BACKGROUND The in-stent restenosis(ISR)rates are reportedly inconsistent despite the increased use of second-generation drug eluting stent(DES).Although bioresorbable vascular scaffold(BVS)have substantial advantages with respect to vascular restoration,the rate of scaffold thrombosis is higher with BVS than with *** treatment strategies have not been established for DES-ISR to *** SUMMARY We report on a case of a 60-year-old man patient with acute coronary *** had a history of ST-segment elevation myocardial infarction associated with very late scaffold thrombosis and treated with a *** angiography revealed significant stenosis,suggesting DES-ISR on the previous *** coherence tomography(OCT)identified a plaque rupture and a disrupted scaffold strut in the neointimal proliferation of *** treat the DES-ISR on the previous BVS,we opted for a drug-coated balloon(DCB)after a balloon angioplasty using a semi-compliant and non-compliant *** patient did not experience adverse cardiovascular events on using a DCB following the use of intensive dual antiplatelet therapy and statin for 24 *** This case highlights the importance of OCT as an imaging modality for characterizing the mechanism of target lesion *** use of a DCB following the administration of optimal pharmacologic therapy may be an optimal strategy for the treatment and prevention of recurrent BVS thrombosis and DES-ISR.

关键词： Bioresorbable vascular scaffold thrombosis In-stent restenosis Drug-coated balloon Optical coherence tomography Intensive dual antiplatelet therapy Case report

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High-risk esophageal varices in patients treated with locoregional therapy for hepatocellular carcinoma:Assessment with liver computed tomography

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World Journal of Gastroenterology 2012年第35期18卷 4905-4911页

作者： Hyojin Kim Dongil Choi Joon Hyeok Lee Soon jin Lee Hangi Jo Geum-Youn Gwak Kwang Cheol koh Moon Seok Choi Seonwoo Kim Department of Radiology and Center for Imaging Science Samsung Medical CenterSungkyunkwan University School of Medicine Department of Medicine Samsung Medical CenterSungkyunkwan University School of Medicine Biostatistics Unit Samsung Biomedical Research InstituteSamsung Medical CenterSungkyunkwan University School of Medicine

AIM： To assess the diagnostic performance of follow- up liver computed tomography （CT） for the detection of high-risk esophageal varices in patients treated with Io- coregional therapy for hepatocellular carcinoma （HCC）. METHODS： We prospectively enrolled 100 patients with cirrhosis who underwent transcatheter arterial chemoembolization, radiofrequency ablation or both procedures for HCCs. All patients underwent upper endoscopy and subsequently liver CT. Three radiolo- gists independently evaluated the presence of high-riskesophageal varices with transverse images alone and with three orthogonal multiplanar reformation （MPR） images, respectively. With endoscopic grading as the reference standard, diagnostic performance was as- sessed by using receiver operating characteristic （ROC） curve analysis. RESULTS： The diagnostic performances （areas under the ROC curve） of three observers with transverse im- ages alone were 0.947 ± 0.031, 0.969 ± 0.024, and 0.916 ＋ 0.038, respectively. The mean sensitivity, spec- ificity, positive predicative value （PPV）, and negative predicative value （NPV） with transverse images alone were 90.1%, 86.39%, 70.9%, and 95.9%, respectively. The diagnostic performances, mean sensitivity, specific- ity, PPV, and NPV with three orthogonal MPR images （0.965 ± 0.025, 0.959 ± 0.027, 0.938 ± 0.033, 91.4%, 89.5%, 76.3%, and 96.6%, respectively） were not su- perior to corresponding values with transverse images alone （P 〉 0.05）, except for the mean specificity （P = 0.039）. CONCLUSION： Our results showed excellent diagnos- tic performance, sensitivity and NPV to detect high-risk esophageal varices on follow-up liver CT after Iocore- gional therapy for HCC,

关键词： Liver computed tomography High-riskesophageal varices Locoregional therapy Hepatocel-lular carcinoma Multiplanar reformation images

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Stress and sleep quality in doctors working on-call shifts are associated with functional gastrointestinal disorders

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World Journal of Gastroenterology 2017年第18期23卷 3330-3337页

作者： Soo-Kyung Lim Seung jin Yoo Dae Lim Koo Chae A Park Han Jun Ryu Yong jin Jung Ji Bong Jeong Byeong Gwan Kim Kook Lae Lee Seong-Joon koh Department of Internal Medicine Seoul National University College of MedicineSeoul National University Boramae Hospital Department of Neurology Seoul National University Boramae HospitalSeoul National University College of Medicine

To investigate the role of sleep quality and psychosocial problems as predictors of functional gastrointestinal disorders (FGIDs) in doctors that work 24 hour-on-call *** this cross-sectional observation study, using the Rome III Questionnaire and Pittsburgh Sleep Quality Index (PSQI), we analyzed 170 doctors with 24 hour-on-call *** the participants that had experienced a 24 hour-on-call shift within the last 6 mo, 48 (28.2%) had FGIDs. Overall prevalence of irritable bowel syndrome (IBS) and functional dyspepsia (FD) were 16.5% and 17.1%, respectively, with 5.3% exhibiting both. Sleep scores (PSQI) (8.79 ± 2.71 vs 7.30 ± 3.43, P = 0.008), the presence of serious psychosocial alarm (83.3% vs 56.6%, P = 0.004), and the proportion of doctors who experienced over two months of recent on-call work (81.2% vs 68.9%, P = 0.044) were significantly different between individuals with or without FGIDs. Multivariate analysis revealed that presenting serious psychosocial alarm was an independent risk factor for prevalence of FD (OR = 5.47, 95%CI: 1.06-28.15, P = 0.042) and poor sleep quality (PSQI ≥ 6) was a predictor of IBS (OR = 4.17, 95%CI: 1.92-19.02, P = 0.016).CONCLUSIONPhysicians should recognize the role of sleep impairment and psychological stress in the development of FGIDs and a comprehensive approach should be considered to manage patients with FGIDs.

关键词： Psychosocial stress Sleep 24 hour-on-call shift Doctors Functional gastrointestinal disorders

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Tenofovir rescue therapy for chronic hepatitis B patients after multiple treatment failures

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World Journal of Gastroenterology 2012年第47期18卷 6996-7002页

作者： Yu jin Kim Dong Hyun Sinn Geum-Youn Gwak Moon Seok Choi Kwang Cheol koh Seung Woon Paik Byung Chul Yoo Joon Hyeok Lee Department of Medicine Samsung Medical CenterSungkyunkwan University School of MedicineSeoul 135-710South Korea

AIM:To evaluate the efficacy and safety of tenofovir disoproxil fumarate(TDF) for chronic hepatitis B(CHB) patients after multiple ***:A total of 29 CHB patients who had a suboptimal response or developed resistance to two or more previous nucleoside/nucleotide analogue(NA) treatments were *** subjects were treated with TDF alone(n = 13) or in combination with lamivudine(LAM,n = 12) or entecavir(ETV,n = 4) for ≥ 6 *** virologic response(CVR) was defined as an achievement of serum hepatitis B virus(HBV) DNA level ≤ 60 IU/mL by real-time polymerase chain reaction method during *** assessment was based on serum creatinine and phosphorus *** patients had histories of LAM and adefovir dipivoxil(ADV) treatment and 18 patients were exposed to LAM,ADV,and ***-seven patients(93.1%) were hepatitis B e antigen(HBeAg) positive and the mean value of the baseline serum HBV DNA level was 5.5 log IU/mL ± 1.7 log IU/*** median treatment duration was 16 mo(range 7 to 29 mo).RESULTS:All the patients had been treated with LAM and developed genotypic and phenotypic resistance to *** to ADV was present in 7 patients and 10 subjects had a resistance to *** patient had a resistance to both ADV and *** cumulative probabilities of CVR at 12 and 24 mo of TDF containing treatment regimen calculated by the Kaplan Meier method were 86.2% and 96.6%,*** one patient failed to achieve CVR,serum HBV DNA level decreased by 3.9 log IU/mL from the baseline and the last serum HBV DNA level during treatment was 85 IU/mL,achieving near *** patients in this study showed viral breakthrough or primary non-response during the follow-up *** cumulative probability of HBeAg clearance in the 27 HBeAg positive patients was 7.4%,12%,and 27% at 6,12,and 18 mo of treatment,*** efficacy of TDF containing regimen was not statistically different according to the presence of specific HBV mutatio

关键词： Tenofovir Chronic hepatitis B Treatment failure

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