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Thermal Characterization and Decomposition Kinetics of Free Anthraquinones from Rhubarb

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Chinese Chemical Letters 2006年第5期17卷 699-702页

作者： li ming ZHANG Xia li Yu Jie DAI College of Bioengineering Tianjin University of Science ＆ Technology Tianjin 300222

The thermal behaviour of aloe-emodin, chrysophanol and physcion and their kinetics have been investigated under non-isothermal conditions by means of differential thermal analysis （DTA） and thermogravimetry （TG）. The thermal characteristics have been determined using the DTA and TG-DTG curves. The non-isothermal kinetic data were analyzed by means of the Achar method and the Madhusudanan-Krishnan-Ninan （MKN） method. The possible reaction mechanisms have been investigated by comparing the kinetic parameters. The kinetic equation for aloe-emodin, chrysophanol and physcion can be expressed as dα/dt=Aexp（-E/RT）1/3（1-α）[-In（1-α]2. The activation energy E （kJ mol^-1） of the three free anthraquinones are 78.09, 89.54, and 107.5 and their InA/s^-1 are 22.98, 36.85 and 43.60, respectively.

关键词： Aloe-emodin chrysophanol physcion thermogravimetry (TG) differential thermoanalysis (DTA) non-isothermal kinetics.

Evaluation of Impact of Major Causes of Death on life Expectancy Changes in China,1990-2005

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Biomedical and Environmental Sciences 2009年第5期22卷 430-441页

作者： YAN-HONG WANG li-ming li Department of Epidemiology&Biostatistics School of Public HealthPeking University Health Science CenterBeijing 100191China

Objective To evaluate the impact of major causes of death on changes of life expectancy in China. Methods life expectancy was calculated by standard life table techniques using mortality data from the national censuses in 1990 and 2000 and the 1% National Population Sampling Surveys in 1995 and 2005, Mortality data about the major causes of death from VR-MOH were used as reference values to estimate their death proportions of the specific age groups by sex and regions, as well as all-cause mortality and age-specific mortality rates of major causes of death. Decomposition method was used to quantitatively evaluate the impact. Results Three key findings were identified in our study. First, China's health challenge was shifted from diseases related to living conditions to those related to behavior and lifestyle, with rural areas relatively lagged behind urban areas, Second, the impacts of cardiovascular diseases and neoplasm on the middle aged and elderly population were stressed. Third, compared to the urban population, the rural population tended to have increasing mortality of neoplasm and cardiovascular diseases, especially in adults at the age of 15-39 years. Conclusion Further efforts should be made to reduce the incidence of neoplasm and cardiovascular diseases, especially in rural areas, by promoting healthy behavior and lifestyle and providing appropriate therapies for all patients in need.

关键词： China life expectancy Cardiovascular disease Neoplasm

Application of Task-Oriented Method of Serial Robot for Mechanism Analysis and Evaluation

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Journal of Harbin Institute of Technology(New Series) 2014年第2期21卷 13-20页

作者： Zhi-Juan Sun Jing Zhao li-ming li College of Mechanical Engineering and Applied Electronics Technology Beijing University of Technology

Revealing the relations among robotic comprehensive performance,configuration,scales and working tasks is the basis to optimize robotic mechanism. Due to the correlation and diversity of the single performance indexes,statistical principles of linear dimension reduction and nonlinear dimension reduction are introduced into comprehensive performance analysis and evaluation for typical serial robot. The robotic mechanism's configuration,scales and task with the best comprehensive performance can be obtained by principal component analysis( PCA) and kernel principal component analysis( KPCA) respectively. The results show that KPCA can reveal the nonlinear relations among different single performance indexes more effectively and provide more comprehensive performance information than PCA. Thus,task-oriented method of serial robot for mechanism analysis and evaluation is proposed,which also provides scientific research basis for the mechanism synthesis and optimum task order.

关键词： serial robot mechanism analysis mechanism synthesis optimum task PCA KPCA

Postoperative multiple metastasis of clear cell sarcoma-like tumor of the gastrointestinal tract in adolescent:A case report

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World Journal of Clinical Cases 2022年第18期10卷 6175-6183页

作者： Wen-Peng Huang li-ming li Jian-Bo Gao Department of Radiology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina

BACKGROUND Clear cell sarcoma-like tumor of the gastrointestinal tract(CCSLGT)is a rare malignant gastrointestinal mesenchymal soft tissue *** genetic feature is EWSR1 gene ***,it is often accompanied by a varying number of CD68-positive osteoclast-like giant *** mostly occurs in the small intestinal wall of young people and *** terms of clinical manifestations,there is no significant difference between it and other gastrointestinal tumors,and the diagnosis depends on immunohistochemistry and gene *** SUMMARY A 16-year-old man developed dizziness and fatigue 2 mo ago,and 10 d ago showed progressive exacerbation of paroxysmal epigastric pain and stopped flatulence and *** tomography showed a soft tissue mass in the distal *** complete resection of the lesion,it was diagnosed by combined immunohistochemical and genetic examination as *** surgery,the patient gradually developed lymph node,liver,lung,bone,left thigh,pleura and adrenal *** survival time was 4 years and 8 *** Whole abdominal computed tomography enhancement is recommended for patients with gastrointestinal *** is no effective treatment for CCSLGT with multiple metastases via the lymphatic system and bloodstream after surgical resection.

关键词： Clear cell sarcoma-like tumor of the gastrointestinal tract Metastasis X-ray computed tomography Case report

Pleomorphic adenoma of the left lacrimal gland recurred and transformed into myoepithelial carcinoma after multiple operations:A case report

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World Journal of Clinical Cases 2022年第11期10卷 3630-3638页

作者： Wen-Peng Huang li-ming li Jian-Bo Gao Department of Radiology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina

BACKGROUND Myoepithelial carcinoma(MC)is a clinically rare malignancy,there is controversy regarding its etiology and its biological behavior is not fully *** surgical resection is the main treatment *** describe a case of pleomorphic adenoma(PA)with multiple postoperative recurrences after malignant transformation,and the history of the disease in this patient was more than 20 *** resection during the first surgery of PA and long-term postoperative follow-up is *** SUMMARY A 34-year-old male with PA and a history of 5 postoperative recurrences over 21 years,each surgically removed,presented 15 d ago with headache,nasal congestion,protrusion of the right eyeball and loss of vision in the right eye,with progressively worsening *** patient underwent surgery,and MC was confirmed by pathology examination.A small PA component was locally visible under light *** patient had a recurrence of the tumor 2 mo after surgery and underwent surgical *** During the first operation for PA,care should be taken not to rupture the envelope to prevent tumor cell implantation,and when complete resection is not possible due to the anatomical site,postoperative radiotherapy is necessary to control the lesion and prevent infiltration and malignant transformation of the tumor to *** tomography and magnetic resonance imaging is important for establishing diagnosis and developing a treatment plan.

关键词： Myoepithelial carcinoma Pleomorphic adenoma Magnetic resonance

Malignant giant cell tumor in the left upper arm soft tissue of an adolescent:A case report

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World Journal of Clinical Cases 2021年第15期9卷 3704-3710页

作者： Wen-Peng Huang li-Na Zhu Rui li li-ming li Jian-Bo Gao Department of Radiology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina

BACKGROUND Giant cell tumor of soft tissue(GCT-ST)is an extremely rare low-grade soft tissue tumor that is originates in superficial tissue and rarely spreads ***-ST has unpredictable *** is mainly benign,but may sometimes become aggressive and potentially increase in size within a short period of *** SUMMARY A 17-year-old man was suspected of having a fracture,based on radiography following left shoulder *** month later,the swelling of the left shoulder continued to increase and the pain was *** tomography(CT)revealed a soft tissue mass with strip-like calcifications in the left *** mass invaded the adjacent humerus and showed an insect-like area of destruction at the edge of the cortical bone of the upper *** marrow cavity of the upper humerus was enlarged,and a soft tissue density was seen in the medullary *** CT revealed multiple small nodules beneath the pleura of both lungs.A bone scan demonstrated increased activity in the left shoulder joint and proximal *** mass showed mixed moderate hypointensity and hyperintensity on T1-weighted images,and mixed hyperintensity on T2-weighted fat-saturated *** final diagnosis of GCT-ST was confirmed by *** GCT-STs should be considered in the differential diagnosis of soft tissue tumors and monitored for large increases in size.

关键词： Bone scan Giant cell tumor Soft tissue Tomography X-ray computed Magnetic resonance imaging Case report

Magnesium based degradable biomaterials： A review

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Frontiers of Materials Science 2014年第3期8卷 200-218页

作者： Xue-Nan GU Shuang-Shuang li Xiao-ming li Yu-Bo FAN Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education School of Biological Science and Medical Engineering Beihang University Beijing 100191 China

Magnesium has been suggested as a revolutionary biodegradable metal for biomedical applications. The corrosion of magnesium, however, is too rapid to match the rates of tissue healing and, additionally, exhibits the localized corrosion mechanism. Thus it is necessary to control the corrosion behaviors of magnesium for their practical use. This paper comprehensively reviews the research progress on the development of representative magnesium based alloys, including Mg-Ca, Mg-Sr, Mg-Zn and Mg-REE alloy systems as well as the bulk metallic glass. The influence of alloying element on their microstructures, mechanical properties and corrosion behaviors is summarized. The mechanical and corrosion properties of wrought magnesium alloys are also discussed in comparison with those of cast alloys. Furthermore, this review also covers research carried out in the field of the degradable coatings on magnesium alloys for biomedical applications. Calcium phosphate and biodegradable polymer coatings are discussed based on different preparation techniques used. We also compare the effect of different coatings on the corrosion behaviors of magnesium alloys substrate.

关键词： magnesium alloy degradable biomaterial coating degradation corrosion

Theoretical study on the reaction of VS^+(~3∑^-,~1Γ)with CO

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Chinese Chemical Letters 2008年第8期19卷 1008-1011页

作者： Shi Wen Yu li Qing Yin li Feng Yao ming li Xiao Guang Xie Department of Chemistry Yunnan University Kunming 650091 China

Two possible reaction mechanisms of VS^＋（^3∑^-, 1^Г） with CO in the gas phase have been studied by using B3LYP/TZVP and CCSD（T）/6-311＋G （3df, 3pd） methods： the O/S exchange reaction （VS^＋＋CO→VO^＋＋CS） and the S-transfer reaction （VS^＋＋ CO → V^＋＋ COS）. The two reactions proceed via two-step and one-step mechanism, respectively. The barriers of the triplet and singlet PESs are 30.6 and 50.9 kcal/mol, respectively, for O/S exchange reaction and 7.3 and 50.2 kcal/mol, respectively, for the S-transfer reaction. The results indicate that the triplet ground state reaction is more favorable, and the S-transfer reaction is more favorable than the O/S exchange reaction, which is in good agreement with the experimental observation.

关键词： Vanadium sulfide ion CO Reaction CCSD(T)

Study on the inclusion interaction of methylated-β-cyclodextrins with albendazole by spectrofluorimetry and its application

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Chinese Chemical Letters 2008年第8期19卷 951-954页

作者： Guo Yan Zhao Hao Wu Sheng li Dong li ming Du Analytical and Testing Center Shanxi Normal University Linfen 041004 China

The inclusion interaction between three types of methylated-β-cyclodextrins （Me-β-CDs） and albendazole （ABZ） was studied by spectrofluorimetry. The result showed that Me-β-CDs reacted with ABZ to form an inclusion complex, 1： 1 stoichiometry for Me- β-CDs-ABZ complex was established and its association constant have been determined from fluorescence data by Benesi- Hildebrand＇s method （double reciprocal plots）. It was noted that 2,6-DM-β-CD exhibited stronger binding ability than other Me-β- CDs. Based on the significant enhancement of fluorescence intensity of inclusion complex, a simple and highly sensitive fluorimetric method is proposed for the determination of ABZ in the presence of 2,6-DM-β-CD. The proposed method was successfully applied to the determination of ABZ in tablets and human urine.

关键词： Methylated-β-cyclodextrins Albendazole Spectrofluorimetry