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World Journal of Gastroenterology 2008年第28期14卷 4535-4539页

作者： Guo-Shuang Feng Jun-ling Ma Benjamin CY Wong lian Zhang Wei-Dong liu Kai-Feng Pan lin Shen Xiao-Dong Zhang jie li Harry HX Xia ji-you li Shiu Kum Lam Wei-Cheng you Department of Cancer Epidemiology Peking University School ofOncology Beijing Cancer Hospital & Institute Beijing 100036 China Department of Medicine University of Hong Kong Hong Kong China Department of Medical Oncology Peking University School of Oncology Beijing Cancer Hospital & Institute Beijing 100036 China Department of Pathology Peking University School of Oncology Beijing Cancer Hospital & Institute Beijing 100036 China Healthy Bureau of linqu County Weifang 262600 Shandong Province China

AIM: To evaluate the long-term risk of gastroduodenal ulcer and cardiovascular events induced by celecoxib in a population-based, randomized, double-blind, placebo-controlled ***: From 2004 to 2006, a total of 1024 Chinese patients (aged 35 to 64 years) with severe chronic atrophic gastritis, intestinal metaplasia or dysplasia were randomly assigned to receive 200 mg of celecoxib twice daily or placebo in linqu County (Shandong Province, China), a high-risk area of gastric cancer. All gastroduodenal ulcer and cardiovascular events occurred were recorded and the patients were followed up for 1.5 years after treatment. At the end of the trial, a systematic interview survey about other adverse events was conducted. RESULTS: Gastroduodenal ulcer was detected in 19 of 463 (3.72%) patients who received celecoxib and 17 of 473 (3.31%) patients who received placebo, respectively (odds ratio = 1.13, 95% CI = 0.58-2.19). Cardiovascular (CV) events occurred in 4 patients who received celecoxib and in 5 patients who received placebo, respectively. Compared with those who received placebo, patients who received celecoxib had no signif icant increase in occurrence of CV events (hazard ratio = 0.84, 95% CI = 0.23-3.15). Among the adverse events acquired by interview survey, only the frequency of bloating was signif icantly higher in patients treated with celecoxib than in those treated with placebo. CONCLUSION: Treatment of gastric cancer with celecoxib is not associated with increased risk of gastroduodenal ulcer and cardiovascular events.

关键词： Celecoxib Gastroduodenal ulcer Cardiovascular diseases Adverse effects Epidemiology Randomized controlled trial

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Photocatalytic activity and kinetics for acid yellow degradation over surface composites of TiO_2-coated activated carbon under different photocatalytic conditions

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Transactions of Nonferrous Metals Society of China 2013年第4期23卷 1019-1027页

作者：曾孟雄李佑稷马明远陈伟李雷勇吉首大学化学化工学院吉首416000

TiO2-coated activated carbon surface （TAs） composites were prepared by a sol-gel method with supercritical pretreatment. The photocatalytic degradation of acid yellow （AY） was investigated under UV radiation to estimate activity of catalysts and determine the kinetics. And the effects of parameters including the initial concentration of AY, light intensity and TiO2 content in catalysts were examined. The results indicate that TAs has a higher efficiency in decomposition of AY than P25, pure TiO2 particles as well as the mixture of TiO2 powder and active carbon. The photocatalytic degradation rate is found to follow the pseudo-first order kinetics with respect to the AY concentration. The new kinetic model fairly resembles the classic Langmuir-Hinshelwood equation, and the rate constant is proportional to the square root of the light intensity in a wide range. However, its absorption performance depends on the surface areas of catalysts. The model fits quite well with the experimental data and elucidates phenomena about the effects of the TiO2 content in TAs on the degradation rate.

关键词： photocatalysis TiO2-coated activated carbon acid yellow composite catalyst

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Anisotropic Mechanical Response of Nacre to Heat Treatment Under Indentation:Effect of Structural Orientation

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Journal of Bionic Engineering 2024年第3期21卷 1453-1464页

作者： Simin liang Yingying li Hongmei ji Xiaowu li Department of Materials Physics and Chemistry School of Materials Science and EngineeringKey Laboratory for Anisotropy and Texture of MaterialsMinistry of EducationNortheastern UniversityShenyang110819China

It is generally considered that heat treatments have a negative impact on the mechanical properties of nacre due to thermal decomposition of the organic ***,the present work investigated the microindentation behavior on fresh and heat-treated nacres from two orthogonal directions,and the results demonstrate that both hardness value and damage tolerance can remain almost unchanged on the cross-section with the organic matrix degeneration,despite a significant deterioration on the platelet *** analyses suggest that the anisotropic response of indentation behavior to heat treatment in nacre is primarily caused by its structural ***,compared with a single layer of irregular interplatelet interfaces in cross-sectional specimens,the multiple layers of parallel interlamellar interfaces in in-plane specimens exhibit a much greater ability to impede indenter-triggered destruction,and heat treatments would reduce the in-plane hardness but nearly have no effect on the cross-sectional ***,the deeper embedding of platelets in cross-sectional specimens enhances their resistance to interface cracking caused by organic matrix degradation at high temperatures,leading to a reduced sensitivity to ***,the indentation behavior of nacre shows different tendencies in response to variations in the organic matrix state along normal and parallel directions.

关键词： Nacre Structural orientation Heat treatment Indentation behavior Organic matrix

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Mycoplasma infections and different human carcinomas

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World Journal of Gastroenterology 2001年第2期7卷 266-269页

作者： Su Huang ji you li Jan Wu lin Meng Cheng Chao Shou Beijing Institute for Cancer Research, Peking University School of Oncology, Beijing 100034. ChinaSu Huang, received B. A from jiangxi Medical College of China in 1994. Now she is a graduate student pursuing a Ph. D degree at the Peking University School of Oncology. Department of Biochemistry and Molecular Biology Beijing Institute for Cancer Research and Peking University School of Oncology.No.1 Da Hong Luo Chang Street Western District Beijing 100034 China. 6201@***

AIM: To explore relationships between human carcinomas and mycoplasma infection. METHODS: Monoclonal antibody PD4, which specifically recognizes a distinct protein from mycoplasma hyorhinis, was used to detect mycoplasma infection in different paraffin embedded carcinoma tissues with immunohistochemistry. PCR was applied to amplify the mycoplasma DNA from the positive samples for confirming immunohistochemistry. RESULTS: Fifty of 90 cases (56%) of gastric carcinoma were positive for mycoplasma hyorhinis. In other gastric diseases, the mycoplasma infection ratio was 28% (18/49) in chronic superficial gastritis, 30% (14/46) in gastric ulcer and 37% (18/49) in intestinal metaplasia. The difference is significant with gastric cancer (chi(2) = 12.06, P lioma was 50.9% (27/53), 52.6% (31/59), 39.7% (25/63) and 41% (38/91), respectively. The mycoplasma DNA was successfully amplified with the DNA extracted from the cancer tissues that were positive for mycoplasma infection (detected with antibody PD4). CONCLUSION: There was high correlation between mycoplasma infection and different cancers, which suggests the possibility of an association between the two. The mechanism involved in oncogenesis by mycoplasma remains unknown.

关键词： Antibodies, Monoclonal Bacterial Proteins Brain Neoplasms Breast Neoplasms DNA, Bacterial Gastrointestinal Neoplasms Humans Immunohistochemistry Lung Neoplasms Mycoplasma purification Mycoplasma Infections Neoplasms Polymerase Chain Reaction Research Support, Non-U.S. Gov't

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Polymorphisms of ICAM-1 are associated with gastric cancer risk and prognosis

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World Journal of Gastroenterology 2012年第4期18卷 368-374页

作者： Meng-Meng Tian,Yu Sun,Zhong-Wu li,Ying Wu,Ai-lian Zhao,ji-you li,Key Laboratory of Carcinogenesis and Translational Research,Department of Pathology,Peking University School of Oncology,Beijing Cancer Hospital and Institute,Beijing 100142,China Key Laboratory of Carcinogenesis and Translational Research Department of Pathology Peking University School of Oncology Beijing Cancer Hospital and Institute Beijing 100142 China.

AIM:To investigate the association between single nu-cleotide polymorphisms (SNPs) in intercellular adhesion molecule-1 (ICAM-1) and the risk,biological behavior and prognosis of gastric cancer (GC) in Chinese ***:The study group consisted of 332 GC patients and 380 healthy *** was performed using polymerase chain reaction and the results were confirmed by *** associa-tion of ICAM-1 K469E polymorphisms and the risk of GC were studied,and the correlation of ICAM-1 K469E polymorphisms with the clinicopathological parameters and prognosis of the patients with complete clinical and follow-up data was ***:Carriers of AA genotype had a significantly increased risk of GC compared with carriers of AG and GG genotypes [odds ratios:1.36;95% confidence in-terval (CI):1.01-1.84;P=0.041].GC patients with AA genotype were more prone to distant metastasis than those carrying AG and GG genotypes (18.9% vs 7.0%,respectively;P=0.002).In addition,patients at stage Ⅳ had significantly more carriers of AA genotype than those of AG and GG genotype (27.4% vs 16.9%,re-spectively;P=0.046).Follow-up study showed that the overall cumulative survival rate was 23.7% in AA geno-type group and 42.9% in AG and GG genotypes *** univariate analysis,AA genotype was correlated with the overall cumulative survival (P=0.034).But in multi-variate analysis,ICAM-1 polymorphism was not an inde-pendent prognostic factor for the overall survival (relative risk,1.145;95% CI:0.851-1.540;P=0.370).CONCLUSION:Polymorphisms of ICAM-1 K469E can be a useful biomarker for identifying individuals with higher risk of GC,predicting disease progression,and guiding individualized treatment.

关键词： Intercellular adhesion molecule-i Genepoiymorphism Gastric cancer Risk Prognosis

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Copper-catalyzed enantioselective desymmetrizing C(sp^(2))-H functionalization of azide-ynamides via α-imino copper carbenes

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Science China Chemistry 2024年第9期67卷 2982-2988页

作者： En-He Huang li-Gao liu you-Wei Yin Hao-Xuan Dong ji-jia Zhou Xin Lu Bo Zhou Long-Wu Ye Key Laboratory for Chemical Biology of Fujian Province and State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

α-Imino metal carbenes are versatile intermediates in organic synthesis,and have broad applications in the assembly of divergent ***,the catalytic enantioselective desymmetrization based onα-imino metal carbenes has not been developed to ***,we disclose an enantioselective desymmetrizing C(sp^(2))-H functionalization of azide-ynamides viaα-imino copper carbenes,leading to the efficient assembly of divergent chiral indoloazepines in generally moderate to excellent yields with high ***,this reaction represents the first enantioselective desymmetrization based onα-imino metal *** synthetic transformations and biological tests show the potential utility of this ***,computational studies are employed to elucidate the reaction mechanism and the origin of enantioselectivity.

关键词： enantioselective desymmetrization metal carbenes copper catalysis nitrene transfer alkynes

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A molecular insight into coke formation process of vacuum residue in thermal cracking reaction

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Petroleum Science 2024年第3期21卷 2130-2138页

作者： ji-Guang li Xin Guo Huan-Di Hou Heavy Oil Processing Department Sinopec Research Institute of Petroleum Processing Co.LtdBeijing100083China

Understanding the coking behaviors has been considered to be really essential for developing better vacuum residue processing technologies.A battery of thermal cracking tests of typical vacuum residue at 410℃ with various reaction time were performed to evaluate the coke formation *** total yields of ideal components including naphtha,atmospheric gas oil(AGO)and vacuum gas oil(VGO)of thermal cracking reactions increased from 10.89%to 40.81%,and the conversion ratios increased from8.05%to 43.33%with increasing the reaction time from 10 to 70 *** asphaltene content increased from 12.14%to a maximum of 22.39%and then decreased,and this maximum of asphaltene content occurred at the end of the coking induction *** asphaltenes during the coking induction period,at the end and after coking induction period of those tested thermal cracking reactions were characterized to disclose the structure changing rules for coke formation process,and the coke formation pathways were discussed to reveal the coke formation process at molecular level.

关键词： Vacuum residue Thermal cracking Asphaltene Coking induction period Sulfur Nitrogen

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Current-carrying tribological behavior of C/Cu contact pairs in extreme temperature and humidity environments for railway catenary systems

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Science China(Technological Sciences) 2024年第8期67卷 2537-2548页

作者： SHEN MingXue ji DeHui HU Qiang XIAO li li QiuPing State Key Laboratory of Performance Monitoring and Protecting of Rail Transit Infrastructure East China Jiaotong UniversityNanchang 330013China School of Materials Science and Engineering East China Jiaotong UniversityNanchang 330013China Institute of Applied Physics Jiangxi Academy of SciencesNanchang 330095China

Many current-carrying contact pairs, such as those found in pantograph-catenary systems, operate in open environments and are susceptible to significant external interference from temperature and humidity variations. This study investigated the evolution of the friction coefficient and contact resistance of C/Cu contact pairs under alternating temperature, humidity, and current conditions. Through experimentation, the wear rate and microtopography of the worn surface were analyzed under various constant parameters. Subsequently, the differences in tribological behavior and current-carrying characteristics of the contact pairs under these three parameters were explored. The results revealed that the decrease in temperature resulted in a significant increase in the friction coefficient of the contact pairs, carbon wear, and copper surface roughness. Additionally, the surface oxidation rate was lower at lower temperatures. Moreover, contact resistance did not consistently increase with decreasing temperature, owing to the combined action of the contact area and the oxide film. Compared with temperature, humidity fluctuations at room temperature exerted less influence on the friction coefficient and contact resistance of the contact pairs. Dry environments rendered carbon materials vulnerable to oxidation and cracking, while excessive humidity fostered abrasive wear and arcing. High-current conditions generally degraded the tribological properties of C/Cu contacts. In the absence of current, the friction coefficient was extremely high, and the copper transfer was high. Under excessive current, copper was susceptible to plowing by carbon micro-bumps and abrasive particles, resulting in a decrease in the friction coefficient. The release of lipids from the carbon surface due to temperature elevation weakened the electrical contact performance and increased the occurrence of arc erosion, thereby exacerbating carbon wear.

关键词： temperature/humidity pantograph-catenary system C/Cu wear current-carrying friction sliding electrical contact

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Effects of phosphorus limitation on sinking velocities of phytoplankton during summer in the Changjiang River Estuary

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Acta Oceanologica Sinica 2024年第6期43卷 131-141页

作者： Xinchi you Qiang Hao jie Zhu Wei Zhang Haiyan jin Dewang li Huanhong ji Yu Ke Feng Zhou Ocean College Zhejiang UniversityZhoushan 316021China State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310000China Key Laboratory of Marine Ecosystem Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Donghai Laboratory Zhoushan 316021China East China Sea Ecological Center Ministry of Natural ResourcesShanghai 201206China Key Laboratory of Marine Ecological Monitoring and Restoration Technologies Ministry of Natural ResourcesShanghai 201206China Observation and Research Station of Yangtze River Delta Marine Ecosystems Ministry of Natural ResourcesZhoushan 316021China

The sinking of phytoplankton is critical to organic matter transportation in the ocean and it is an essential process for the formation of coastal hypoxic *** study was based on a field investigation conducted during the summer of 2022 in the Changjiang River(Yangtze River) Estuary(CJE) and its adjacent *** settling column method was employed to measure the sinking velocity(SV) of different size fractions of phytoplankton at the surface of the sea and to analyze their environmental control *** findings reveal significant spatial variation in phytoplankton SV(-0.55-2.41 m/d) within the ***-speed sinking was predominantly observed in phosphate-depleted regions beyond the CJE *** the same time,an upward trend was more commonly observed in the phosphate-rich regions near the CJE *** SV ranges for different sizefractionated phytoplankton,including micro-(>20 μm),nano-(2-20 μm),and picophytoplankton(0.7-2 μm),were-0.50-4.74 m/d,-1.04-1.59 m/d,and-1.24-1.65 m/d,*** analysis revealed a significant negative correlation between SV and dissolved inorganic phosphorus(DIP),implying that the influence of DIP contributes to *** variations in phytoplankton alkaline phosphatase activity suggested a significant increase in SV across all size fractions in the event of phosphorus *** communities with limited photo synthetic capacity(maximum photochemical efficience,Fv/Fm link between sinking and alterations in physiological conditions due to phosphate *** findings from the in situ phosphate enrichment experiments confirmed a marked decrease in SV following phosphate *** findings suggest that phosphorus limitation is the primary driver of elevated SV in the *** study enhances the comprehension of the potential mechanisms underlying hypoxic zone formation in the CJE,providing no

关键词： phytoplankton sinking velocity Changjiang River Estuary phosphorus limitation alkaline phosphatase

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Machine learning model based on non-convex penalized huberized-SVM

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Journal of Electronic Science and Technology 2024年第1期22卷 81-94页

作者： Peng Wang ji Guo lin-Feng li School of Finance and Economics Xizang Minzu UniversityXianyang712082China Research Center for Quality Development of Xizang Special Industries Xianyang712082China School of Computer Science and Technology Xinjiang UniversityUrumqi830017China

The support vector machine(SVM)is a classical machine learning *** the hinge loss and least absolute shrinkage and selection operator(LASSO)penalty are usually used in traditional ***,the hinge loss is not differentiable,and the LASSO penalty does not have the Oracle *** this paper,the huberized loss is combined with non-convex penalties to obtain a model that has the advantages of both the computational simplicity and the Oracle property,contributing to higher accuracy than traditional *** is experimentally demonstrated that the two non-convex huberized-SVM methods,smoothly clipped absolute deviation huberized-SVM(SCAD-HSVM)and minimax concave penalty huberized-SVM(MCP-HSVM),outperform the traditional SVM method in terms of the prediction accuracy and classifier *** are also superior in terms of variable selection,especially when there is a high linear correlation between the *** they are applied to the prediction of listed companies,the variables that can affect and predict financial distress are accurately filtered *** all the indicators,the indicators per share have the greatest influence while those of solvency have the weakest *** companies can assess the financial situation with the indicators screened by our algorithm and make an early warning of their possible financial distress in advance with higher precision.

关键词： Huberized loss Machine learning Non-convex penalties Support vector machine(SVM)

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