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Chemical Research in Chinese Universities 2008年第6期24卷 726-730页

作者： DING Jie-lian LIN Ling XU jian-dong zeng Chong-yu College of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing 210009 P R. China

0.5%Pt-K/γ-Al2O3 catalysts for the synthesis of o-phenylphenol（OPP） from o-cyclohexenyl-cyclohexanone （dimer） dehydrogenation were prepared by means of a two subsequent impregnation method. The effects of catalyst preparation parameters, such as K promoters, calcination, and reduction conditions, were investigated. The results showed that the addition of K2SO4 to Pt/γ-Al2O3 catalyst notably promoted the selectivity of OPP, and its optimum content was found to be 6% in mass fraction. The higher activity was obtained when Pt/γ-Al2O3 catalyst was calcined in nitrogen atmosphere at 400--500 ℃ and then reduced at the same temperature for 3 h in hydrogen atmosphere. The conversion of the dimer and the selectivity of OPP were always above 99% and 90%, respectively, over 0.5%Pt-6% K2SO4/γ-Al2O3 catalyst during the pilot scale test of 8000 h.

关键词： o-Phenylphenol Pt catalyst K promoters Calcinations Reduction

Effect of advanced age on plasma homocysteine levels and its association with ischemic stroke in non-valvular atrial fibrillation

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Journal of Geriatric Cardiology 2017年第12期14卷 743-749页

作者： Yan YAO Li-jian GAO Yong ZHOU Jing-Hua ZHAO Qiang LV jian-zeng dong Mei-Sheng SHANG Department of Cardiology Beijing Anzhen Hospital CapitalMedical University Beijing China Center for coronary heart disease Department of Cardiology Cardiovascular Institute & Fuwai Hospital CAMS & PUMC National Center for Heart Dis- ease Beijing China Beijing Institute of Heart Lung and Blood Vessel Diseases Beijing Anzhen Hospital Capital Medical University Beijing China

Background Elevated homocysteine （Hcy） has been reported to be associated with cardiovascular events in atrial fibrillation （AF） pa- tients, while the age-related expression pattern of plasma Hcy in AF remains unknown. The study was aimed to investigate the effect of ad- vanced age on plasma Hcy levels and its association with ischemic stroke in non-valvular AF patients. Methods A total of 2562 consecu- tive patients with non-valvular AF and 535 controls were enrolled and divided into six age groups. Plasma Hcy levels were analyzed among different age groups, and the effect of advanced age on Hcy was investigated. Results Plasma Hcy levels did not show any difference among groups aged below 65 years, while it increased sharply in patients aged 65-74 years and aged over 75 years （15.7 ±4.6 μmol/L, 17.1 ±4.9 μmol/L, both P 〈 0.01 compared with the first four age groups）. Hcy was much higher in AF patients than in controls at the same age group （all P 〈 0.05）. The proportion of patients with hyperhomocysteinemia increased gradually with age from 32.3%, 29.2%, 31.2%, 32.4%, 45.9%, to 51.4% in six age groups. The concentration of Hcy in AF patients with ischemic stroke increased progressively with age, and was higher than those without stroke at the same age. Logistic regression analysis demonstrated that age 65-74 years [odds ratios （OR）： 1.742, 95% confidence interval （CI）： 1.223-2.482, P = 0.002] and age ≥ 75 years （OR： 2.637, 95% CI： 1.605-4.335, P 〈 0.001） were significantly independent predictors of elevated plasma Hcy levels. Conclusions Advanced age was significantly associated with elevated Hcy levels, which may provide a possible explanation for the progressive increase in ischemic stroke especially in elderly AF patients.

关键词： Advanced age Atrial fibrillation Homocysteine Ischemic stroke

A Review on Particle Reinforced Mg Matrix Composites Fabricated by Powder Metallurgy

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 391-400页

作者： Zhiyuan Liu Li Jin jian zeng Fulin Wang Fenghua Wang Shuai dong Jie dong National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composite School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

This paper provides a comprehensive review of research progress in particle-reinforced Mg matrix composites prepared via powder *** article discusses different strategies,such as micro-sized,nano-sized particles,and multi-particle hybridization,which has been employed to enhance the performance of the *** addition,a range of preparation techniques that optimize the dispersion of the reinforcing particles are *** paper also highlights how the different configurations between the reinforcements and matrix alloy impact the composites’***,the article outlines the prospects of particles reinforced Mg matrix composites fabricated via powder metallurgy and recommends modification methods that could be explored to further develop these materials for various applications.

关键词： Magnesium matrix composites Reinforcing particle Powder metallurgy Mechanical properties Configuration

Dabigatran-induced esophageal injury:a case report

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Chinese Medical Journal 2020年第23期133卷 2897-2898页

作者： Jing-Rui Zhang Chang-Yi Li Song-Nan Li jian-zeng dong Chang-Sheng Ma Department of Cardiology Beijing Anzhen HospitalCapital Medical UniversityBeijing 100029China

To the Editor:Atrial fibrillation(AF)is one of the leading risk factors for stroke and is associated with a fivefold increase in the incidence of *** years,warfarin has been prescribed to lower the thrombotic risk in patients with ***,because of the finicky nature of warfarin(ie,unpredictable pharmacokinetics,frequent international normalized ratio testing,complex food-drug interactions,etc.),it has been incrementally replaced by multiple direct oral anticoagulants(DOACs).Dabigatran,a potent,competitive,and reversible DOAC that directly targets thrombin,was approved by the US Food and Drug Administration in 2010 as an alternative antithrombotic option for nonvalvular *** the randomized evaluation of long-term anticoagulation therapy(RE-LY)trial(a noninferiority trial comparing warfarin with dabigatran in patients with AF)showed that dabigatran is as successful as warfarin for preventing stroke or systemic embolism,its adverse effects also need attention.[1]Accumulating case reports have attracted attention to the issue of dabigatran-induced esophagitis(DIE).[2,3]Recent studies have found that elderly patients are more likely to develop DIE.[4]However,herein,we present a case of a younger male who developed DIE after taking dabigatran.

关键词： esophageal younger prescribed

Unlocking the Potential of Poly(butylene succinate)through Incorporation of Vitrimeric Network Based on Dynamic Imine Bonds

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Chinese Journal of Polymer Science 2024年第10期42卷 1414-1424,I0006页

作者： Shan-Song Wu Hui-Juan Lu Yi-dong Li Shui-dong Zhang jian-Bing zeng Chongqing Key Laboratory of Soft-Matter Material Manufacturing School of Chemistry and Chemical EngineeringSouthwest UniversityChongqing400715China School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou510640China

Poly(butylene succinate)(PBS)exhibits many advantages,such as renewability,biodegradability,and impressive thermal and mechanical properties,but is limited by the low melt viscosity and strength resulted from the linear *** address this,vitrimeric network was introduced to synthesize PBS vitrimers(PBSVs)based on dynamic imine bonds through melt polymerization of hydroxyl-terminated PBS with vanillin derived imine containing compound and hexamethylene diisocyanate using trimethylolpropane as a crosslinking *** with different crosslinking degrees were synthesized through changing the content of the crosslinking *** effect of crosslinking degree on the thermal,theological,mechanical properties,and stress relaxation behavior of the PBSVs was studied in *** results demonstrated that the melt viscosity,melt strength,and heat resistance were enhanced substantially without obvious depression in crystallizability,thermal stability,and mechanical properties through increasing crosslinking *** addition,the PBSVs exhibit thermal reprocessability with mechanical properties recovered by more than 90%even after processing for three ***,PBSV with improved melt properties shows significantly improved foamability compared to commercial *** research contributes to the advancement of polymer technology by successfully developing PBS vitrimers with improved properties,showcasing their potential applications in sustainable and biodegradable materials.

关键词： Poly(butylene succinate) Vitrimer Imine bonds Foamability

Fully Automatic Scar Segmentation for Late Gadolinium Enhancement MRI Images in Left Ventricle with Myocardial Infarction

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Current Medical Science 2021年第2期41卷 398-404页

作者： Zheng-hong WU Li-ping SUN Yun-long LIU Dian-dian dong Lv TONG dong-dong DENG Yi HE Hui WANG Yi-bo SUN jian-zeng dong Ling XIA College of Biomedical Engineering&Instrument Science Zhejiang UniversiryHangzhou 310027China Department of Cardiology the First Affiliated Hospital of Zhengzhou UniversiryZhengzhou 450052China School of Biomedical Engineering Dalian University of TechnologyDalian 116024China Department of Cardiology Beijing Anzhen HospitalCapital Medical University and National Clinical Research Center for Cardiovascular DiseasesBeijing 100029China Department of Cardiology Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China

Numerous methods have been published to segment the infarct tissue in theleft ventricle, most of them either need manual work, post-processing, or suffer from poorreproducibility. We proposed an automatic segmentation method for segmenting the infarct tissue irleft ventricle with myocardial infarction. Cardiac images of a total of 60 diseased hearts (55 humanhearts and 5 porcine hearts) were used in this study. The epicardial and endocardial boundariesof the ventricles in every 2D slice of the cardiac magnetic resonance with late gadoliniumenhancement images were manually segmented. The subsequent pipeline of infarct tissuesegmentation is fully automatic. The segmentation results with the automatic algorithm proposed inthis paper were compared to the consensus ground truth. The median of Dice overlap between ourautomatic method and the consensus ground truth is 0.79. We also compared the automatic methodwith the consensus ground truth using different image sources from diferent centers with diferentscan parameters and different scan machines. The results showed that the Dice overlap with thepublic dataset was 0.83, and the overall Dice overlap was 0.79. The results show that our method isrobust with respect to different MRI image sources, which were scanned by different centers withdifferent image collection parameters. The segmentation accuracy we obtained is comparable toor better than that of the conventional semi-automatic methods. Our segmentation method may beuseful for processing large amount of dataset in clinic.

关键词： myocardial infarction cardiac magnetic resonance with late gadolinium enhancement automatic scar segmentation

Analysis of Coronary Angiography Video Interpolation Methods to Reduce X-ray Exposure Frequency Based on Deep Learning

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Cardiovascular Innovations and Applications 2021年第3期6卷 17-24页

作者： Xiao-lei Yin dong-xue Liang Lu Wang Jing Qiu Zhi-yun Yang jian-zeng dong Zhao-yuan Ma The Future Laboratory Tsinghua UniversityChengfu Road 160HaidianBeijingChina Center for Cardiology Beijing Anzhen HospitalCapital Medical UniversityAnzhen RoadBeijingChina The First Affi liated Hospital of Zhengzhou University Jianshe East RoadErqi DistrictZhengzhouChina

Cardiac coronary angiography is a major technique that assists physicians during interventional heart *** X-ray irradiation,the physician injects a contrast agent through a catheter and determines the coronary arteries’state in real ***,to obtain a more accurate state of the coronary arteries,physicians need to increase the fre-quency and intensity of X-ray exposure,which will inevitably increase the potential for harm to both the patient and the *** the work reported here,we use advanced deep learning algorithms to fi nd a method of frame interpola-tion for coronary angiography videos that reduces the frequency of X-ray exposure by reducing the frame rate of the coronary angiography video,thereby reducing X-ray-induced damage to *** established a new coronary angiography image group dataset containing 95,039 groups of images extracted from 31 *** group includes three consecutive images,which are used to train the video interpolation network *** apply six popular frame interpolation methods to this dataset to confi rm that the video frame interpolation technology can reduce the video frame rate and reduce exposure of physicians to X-rays.

关键词： coronary angiography video interpolation deep learning X-ray exposure frequency

Promising xenograft animal model recapitulating the features of human pancreatic cancer

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World Journal of Gastroenterology 2020年第32期26卷 4802-4816页

作者： Jin-Xin Miao jian-Yao Wang Hao-Ze Li Hao-Ran Guo Louisa S Chard Dunmall Zhong-Xian Zhang Zhen-Guo Cheng dong-Ling Gao jian-zeng dong Zhong-De Wang Yao-He Wang Sino-British Research Centre for Molecular Oncology National Centre for International Research in Cell and Gene TherapyAcademy of Medical SciencesZhengzhou UniversityZhengzhou 450000Henan ProvinceChina Academy of Chinese Medical Sciences Henan University of Chinese MedicineZhengzhou 450000Henan ProvinceChina Centre for Biomarkers and Biotherapeutics Barts Cancer InstituteQueen Mary University of LondonLondon EC1M6BQUnited Kingdom Department of Cardiology Beijing Anzhen HospitalCapital Medical UniversityBeijing 100029China Department of Animal Dairy and Veterinary SciencesUtah State UniversityLogan UT 84341United States

BACKGROUND Multiple sites of metastasis and desmoplastic reactions in the stroma are key features of human pancreatic cancer(PC).There are currently no simple and reliable animal models that can mimic these features for accurate disease *** To create a new xenograft animal model that can faithfully recapitulate the features of human *** Interleukin 2 receptor subunit gamma(IL2RG)gene knockout Syrian hamster was created and characterized.A panel of human PC cell lines were transplanted into IL2RG knockout Syrian hamsters and severe immune-deficient mice subcutaneously or *** growth,local invasion,remote organ metastasis,histopathology,and molecular alterations of tumor cells and stroma were compared over *** The Syrian hamster with IL2RG gene knockout(named ZZU001)demonstrated an immune-deficient phenotype and ***001 hamsters faithfully recapitulated most features of human PC,in particular,they developed metastasis at multiple *** tissues derived from ZZU001 hamsters displayed desmoplastic reactions in the stroma and epithelial to mesenchymal transition phenotypes,whereas PC tissues derived from immune-deficient mice did not present such *** ZZU001 hamsters engrafted with human PC cells are a superior animal model compared to immune-deficient ***001 hamsters can be a valuable animal model for better understanding the molecular mechanism of tumorigenesis and metastasis and the evaluation of new drugs targeting human PC.

关键词： Pancreatic cancer Xenotrans plantation Syrian hamster IL-2 receptor gamma chain gene Metastasis Animal model

Single nucleus/cell RNA-seq of the chicken hypothalamicpituitaryovarian axis offers new insights into the molecular regulatory mechanisms of ovarian development

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Zoological Research 2024年第5期45卷 1088-1107页

作者： dong Leng Bo zeng Tao Wang Bin-Long Chen Di-Yan Li Zhuan-jian Li School of Pharmacy Chengdu UniversityChengduSichuan 610106China College of Animal Science and Technology Sichuan Agricultural UniversityChengduSichuan 611130China College of Animal Science Xichang UniversityXichangSichuan 615000China College of Animal Science and Technology Henan Agricultural UniversityZhengzhouHenan 450046China

The hypothalamic-pituitary-ovarian(HPO)axis represents a central neuroendocrine network essential for reproductive *** its critical role,the intrinsic heterogeneity within the HPO axis across vertebrates and the complex intercellular interactions remain poorly *** study provides the first comprehensive,unbiased,cell type-specific molecular profiling of all three components of the HPO axis in adult Lohmann layers and Liangshan Yanying *** the hypothalamus,pituitary,and ovary,seven,12,and 13 distinct cell types were identified,*** indicated that the pituitary adenylate cyclase activating polypeptide(PACAP),follicle-stimulating hormone(FSH),and prolactin(PRL)signaling pathways may modulate the synthesis and secretion of gonadotropin-releasing hormone(GnRH),FSH,and luteinizing hormone(LH)within the hypothalamus and *** the ovary,interactions between granulosa cells and oocytes involved the KIT,CD99,LIFR,FN1,and ANGPTL signaling pathways,which collectively regulate follicular *** SEMA4 signaling pathway emerged as a critical mediator across all three tissues of the HPO ***,gene expression analysis revealed that relaxin 3(RLN3),gastrin-releasing peptide(GRP),and cocaine-and amphetamine regulated transcripts(CART,also known as CARTPT)may function as novel endocrine hormones,influencing the HPO axis through autocrine,paracrine,and endocrine *** analyses between Lohmann layers and Liangshan Yanying chickens demonstrated higher expression levels of GRP,RLN3,CARTPT,LHCGR,FSHR,and GRPR in the ovaries of Lohmann layers,potentially contributing to their superior reproductive *** conclusion,this study provides a detailed molecular characterization of the HPO axis,offering novel insights into the regulatory mechanisms underlying reproductive biology.

关键词： Chickens Single nucleus/cell transcriptome Hypothalamic-pituitary-ovarian axis Signal crosstalk Hormones

Development characteristics and controlling factors of fractures in lacustrine shale and their geological significance for evaluating shale oil sweet spots in the third member of the Shahejie Formation in the Qikou Sag, Bohai Bay Basin

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Petroleum Science 2024年第2期21卷 791-805页

作者： Xu zeng Tao Yang jian-Wei Feng Cong-Sheng Bian Ming Guan Wei Liu Bing-Cheng Guo Jin dong Research Institute of Petroleum Exploration and Development China National Petroleum CorporationBeijing100083China College of Geosciences China University of Petroleum(Beijing)Beijing102249China Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China School of Earth Sciences China University of PetroleumQingdao266400ShandongChina

Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fractures, remain controversial. In this study, we integrate thin section analysis and microcomputed tomography(CT) data from several lacustrine shale samples from the third member(Es3) of the Shahejie Formation, Qikou Sag, Bohai Bay Basin, to assess the fractures in detail. The goal is to reveal the development characteristics, controlling factors, and geological significance for evaluating sweet spots in a shale oil play. The fractures in the Es3contain high-angle structural and horizontal bed-parallel fractures that are mostly shear and extensional. Various factors influence fracture development,including lithofacies, mineral composition, organic matter content, and the number of laminae. Structural fractures occur predominantly in siltstone, whereas bed-parallel fractures are abundant in laminated shale and layered mudstone. A higher quartz content results in higher shale brittleness, causing fractures, whereas the transformation between clay minerals contributes to the development of bedparallel fractures. Excess pore pressure due to hydrocarbon generation and expulsion during thermal advance can cause the formation of bed-parallel fractures. The density of the bed-parallel and structural fractures increases with the lamina density, and the bed-parallel fractures are more sensitive to the number of laminae. The fractures are critical storage spaces and flow conduits and are indicative of sweet spots. The laminated shale in the Es3with a high organic matter content contains natural fractures and is an organic-rich, liquid-rich, self-sourced shale play. Conversely, the siltstone, massive mudstone, and argillaceous carbonate lithofacies contain lower amounts of organic matter and do not have bed-parallel fractures. However, good reservoirs can form in th

关键词： Fractures Development characteristics Controlling factors Shale oil Sweet spot