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Synthesis of 2-Oxazolines from Ethyl α-Cyanocinnamate Derivatives with Acetamide and N-Bromosuccinimide

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Chemical Research in Chinese Universities 2013年第4期29卷 699-705页

作者： CHEN Zhan-guo XIA Wei wen hua WANG Dan li Ya-nan HU Jun-li Key Laboratory of Macromolecular Science of Shaanxi Province School of Chemistry and Chemical Engineering Shaanxi Normal University Xi'an 710062 P. R. China

An efficient method for the one-pot synthesis of 2-oxazolines from ethyl a-cyanocinnamate derivatives with acetamide and N-bromosuccinimide（NBS） in the presence of K3PO4 was developed. The reaction was performed smoothly and cleanly to give 2-oxazolines in good to excellent yields（up to 95%） in acetone at room temperature. Thirteen examples were investigated and the results indicated that a large range of a-cyanocinnamate derivatives could be suitable for this method. Based on the outcomes of experiment, a possible consecutive nucleophilic addition- cyclization pathway was proposed.

关键词： One-pot synthesis Oxazoline Acetamide N-Bromosuccinimide(NBS) Regioselectivity Nucleophilic ad-dition-cyclization

Prediction of risk factors for lymph node metastasis in early gastric cancer

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World Journal of Gastroenterology 2013年第20期19卷 3096-3107页

作者： Gang Ren Rong Cai wen-Jie Zhang Jin-Ming Ou Ye-Ning Jin wen-hua li Department of Radiology Xinhua HospitalShanghai Jiaotong University Medical School Department of Radiochemotherapy Ruijin HospitalShanghai Jiaotong University Medical School Department of Surgery Xinhua HospitalShanghai Jiaotong University Medical School

AIM:To explore risk factors for lymph node metastases in early gastric cancer(EGC) and to confirm the appropriate range of lymph node ***:A total of 202 patients with EGC who underwent curative gastrectomy with lymphadenectomy in the Department of Surgery,Xinhua Hospital and Ruijin Hospital of Shanghai Jiaotong University Medical School between November 2003 and July 2009,were retrospectively *** the surgical procedure and the extent of lymph node dissection were based on the recommendations of the Japanese gastric cancer treatment *** macroscopic type was classified as elevated(type Ⅰ or Ⅱa),flat(Ⅱb),or depressed(Ⅱc or Ⅲ).Histopathologically,papillary and tubular adenocarcinomas were grouped together as differentiated adenocarcinomas,and poorly differentiated and signet-ring cell adenocarcinomas were regarded as undifferentiated *** and multivariate analyses of lymph node metastases and patient and tumor characteristics were ***:The lymph node metastases rate in patients with EGC was 14.4%.Among these,the rate for mucosal cancer was 5.4%,and 8.9% for submucosal *** analysis showed an obvious correlation between lymph node metastases and tumor location,depth of invasion,morphological classification and venous invasion(χ 2 = 122.901,P = 0.001;χ 2 = 7.14,P = 0.008;χ 2 = 79.523,P = 0.001;χ 2 = 8.687,P = 0.003,respectively).In patients with submucosal cancers,the lymph node metastases rate in patients with venous invasion(60%,3/5) was higher than in those without invasion(20%,15/75)(χ 2 = 4.301,P = 0.038).Multivariate logistic regression analysis revealed that the depth of invasion was the only independent risk factor for lymph node metastases in EGC [P = 0.018,Exp(B) = 2.744].Among the patients with lymph node metastases,29 cases(14.4%) were at N1,seven cases were at N2(3.5%),and two cases were at N3(1.0%).Univariate analysis of variance revealed a close relationship between the dep

关键词： Gastric neoplasm Lymph node metastasis Risk factors Gastrectomy Lymphadenectomy

Effect of Gd addition on mechanical and microstructural properties of Mg-xGd-2.6Nd-0.5Zn-0.5Zr cast alloys

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China Foundry 2020年第3期17卷 212-218页

作者： liang Zhan Yi-zhi Le Zhi-jun Feng Yan-chun Lou Ming Ruan hua-wen li Key Lab of Electromagnetic Processing of Materials Northeastern UniversityShenyang 110819China State Key Laboratory of light Alloy Casting Technology for High-end Equipment Shenyang Research Institute of Foundry Co.Ltd.Shenyang 110022China AECC Zhongchuan Transmission Machinery Co. Ltd.Changsha 410200China

The Mg-xGd-2.6Nd-0.5Zn-0.5Zr(x=0,3.0,4.5 and 6.0,wt.%)alloys were prepared by gravity casting and then T6 *** of the alloy were observed using optical microscopy and scanning electron *** show that the as-cast alloys contained network Mg3Gd phases,blocky and needle-like Mg12(Nd,Gd)*** a(Zr)particle inclusions in the a(Mg)matrix are also *** of the secondary phases decreases as Gd content *** test results show that the tensile and yield strengths of all the alloys increase as Gd content increases under the as-cast and T6 conditions,but the elongation exhibits the opposite *** blocky Mg12(Nd,Gd)phases appear and act as crack initiator and deteriorates the experimental alloys’ductility with the increase of Gd content,especially as Gd content increases to 6.0 wt.%,so the Mg-6.0Gd-2.6Nd-0.5Zn-0.5Zr alloy has the lowest elongation value compared to the other alloys *** T6 treatment,the Mg-4.5Gd-2.6Nd-0.5Zn-0.5Zr alloy exhibits the optimal mechanical properties both at room temperature and 250℃.

关键词： Mg-xGd-Nd-Zn-Zr alloys mechanical properties microstructure Gd addition

Oxygen-vacancy-related dielectric relaxation behaviours and impedance spectroscopy of Bi(Mg_(1/2)Ti_(1/2))O_(3) modified BaTiO_(3) ferroelectric ceramics

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Journal of Materiomics 2018年第3期4卷 194-201页

作者： Ming-Ding li Xin-Gui Tang Si-Ming Zeng Yan-Ping Jiang Qiu-Xiang liu Tian-Fu Zhang wen-hua li School of Physics&Optoelectric Engineering Guangdong University of TechnologyGuangzhou Higher Education Mega CentreGuangzhou 510006People's Republic of China Laboratory Teaching Centre Guangdong University of TechnologyGuangzhou Higher Education Mega CentreGuangzhou 510006People's Republic of China

Lead-free ferroelectric ceramics(1-x)BaTiO_(3-x)Bi(Mg_(1/2)Ti_(1/2))O_(3)(x=0.0-0.07)were synthesized by conventional solid state reaction method and the correlation of structure,dielectric,ferroelectric and impedance properties were *** was found that T_(m) andε_(m) showed decreasing trend with the increase of BMT *** high-temperature dielectric relaxation behaviour was observed in all the *** activation energy calculated from impedance(E_(a))and conductivity(E_(cond)),which revealed that the relaxation behaviours were linked with the migration of *** values of E_(a)were almost equivalent to *** was concluded that the short-range hopping of oxygen vacancy contributed to the dielectric relaxation and long-distance movement of doubly ionized oxygen vacancies contributed to the *** the other hand,with increasing BMT contents,it was found that P-E loops became slimmer and slimmer,which indicated the increase of relaxor *** temperature dependence of P-E loops for 0.98BT-0.02BMT ceramic clearly showed the transition process from ferroelectric to relaxed ferroelectrics.

关键词： BTeBMT ceramic Dielectric Ferroelectric Impedance Oxygen vacancies

Mucosal bacterial dysbiosis in patients with nodular lymphoid hyperplasia in the terminal ileum

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World Journal of Gastroenterology 2022年第8期28卷 811-824页

作者： Qiao-li Jiang You Lu Meng-Jie Zhang Zhen-Yu Cui Zhong-Mei Pei wen-hua li Lun-Gen Lu Jing-Jing Wang Ying-Ying Lu Department of Gastroenterology Jiading Branch of Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 201803China Department of Gastroenterology Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 201620China Shanghai Key Laboratory of Pancreatic Diseases Institute of Translational MedicineShanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 201620China

BACKGROUND Nodular lymphoid hyperplasia(NLH)in the small intestine is a rare benign lesion characterized by multiple small nodules on the intestinal *** with terminal ileal NLH may experience long-term abdominal pain,diarrhea,and abdominal distension,among other *** with probiotics could mitigate these *** is linked to the immune system,and it may result from accumulation of plasma-cell precursors due to a maturational defect during the development of B *** intestinal microbiome plays an essential role in the immune ***,we speculate that the gut flora plays a key role in terminal ileal *** To explore the correlation between intestinal flora and terminal ileal *** We collected mucosal biopsy samples that were obtained via colonoscopy from 15 patients with terminal ileal NLH(the test group)and 15 normal subjects(the control group).We subsequently performed 16 S-r RNA gene amplicon sequencing of these samples,and the results were evaluated using alpha diversity,beta diversity and microbial composition *** Phylogenetic Investigation of Communities by Reconstruction of Unobserved States was used to predict the metabolic pathways and orthologous groups according to the Kyoto Encyclopedia of Genes and Genomes *** Compared with the control group,the terminal ileal NLH group showed an increased alpha diversity(P<0.05).The overall intestinal microbiota in the NLH group was significantly different from that of the control group(P<0.05),implying that there was the dysbiosis in the terminal ileal NLH *** relative abundance of phylum Bacteroidetes was significantly lower in the NLH group,while that of Patescibacteria and Campilobacterota was significantly *** genus Bacteroides was the dominant gut microbiota in both groups,but its abundance was significantly lower in the test group than it was in the control ***,the relative abundances of Haemophilus,Strep

关键词： Hyperplasia Bacteroides Small intestine Microbiome Helicobacter pylori Colonoscopy

Research Progress on the Relationship between Coronary Artery Calcification and Chronic Renal Failure

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Chinese Medical Journal 2018年第5期131卷 608-614页

作者： Jun Lai Gael Akindavyi Qiang Fu Zhi-liang li Hui-Min Wang li-hua wen Department of Cardiology Zhujiang Hospital Southern Medical University Guangzhou Guangdong 510280 China

Objective： Coronary artery calcification （CAC） is thought to be a controlled metabolic process that is very similar to the formation of new bone. In patients with chronic renal failure （CRF）, CAC is very common, and CAC severity correlates with the deterioration of renal lilnction. We summarized the current understanding and emerging findings of the relationship between CAC and CRF. Data Sources： All studies were identified by systematically searching PubMed, Embase, and CNKI databases for the terms ＂coronary calcification＂, ＂＇chronic renal failure＂, ＇~vascular smooth muscle cell＂, and their synonyms until September 2017. Study Selection： We examined the titles and abstracts of all studies that met our search strategy thoroughly. The full text of relevant studies was evaluated. Reference lists of retrieved articles were also scrutinized for the additional relevant studies. Results： CRF can accelerate CAC progression. CRF increases the expression of pro-inflamrnatory factors, electrolyte imbalance （e.g., of calcium, phosphorus）, parathyroid hon^none, and uremic toxins and their ability to promote calcification. These factors, through the relevant signaling pathways, trigger vascular smooth muscle cells to transtbrm into osteoblast-like cells while inhibiting the reduction of vascular calcification factors, thus inducing further CAC. Conclusions： Coronary heart disease in patients with CRF is due to multiple factors. Understanding the mechanism of CAC can help interventionists to protect the myocardium and reduce the prevalence of coronary heart disease and mortality.

关键词： Chronic Renal Failure Coronary Calcification Vascular Smooth Muscle Cell

ROLE OF SERUM HAPTOGLOBIN IN POSTBURN B-LYMPHOCYTE DYSFUNCTION

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中华创伤杂志 1996年第2期 79-81页

作者： WANG Feng jun, huaNG wen hua, li Ao Burn Research Institute, Southwestern Hospital, The Third Military Medical University, Chongqing, 630038

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基于LuGre模型的有摩擦结构自适应主动振动控制

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振动与冲击 2011年第12期30卷 69-73页

作者：刘勇文立华西北工业大学航天学院西安710072

针对参数不确定的有摩擦结构振动控制问题,设计一种基于LuGre动态摩擦模型的模型参考自适应控制器(MRAC)。采用LuGre动态模型描述系统摩擦力,建立单自由度有摩擦结构的动力学模型;以理想的Skyhook结构为参考模型,使用双观测器估计摩擦状... 详细信息

针对参数不确定的有摩擦结构振动控制问题,设计一种基于LuGre动态摩擦模型的模型参考自适应控制器(MRAC)。采用LuGre动态模型描述系统摩擦力,建立单自由度有摩擦结构的动力学模型;以理想的Skyhook结构为参考模型,使用双观测器估计摩擦状态,设计了一种模型参考自适应主动振动控制器,并通过Iyapunov方法证明整个闭环系统具有全局稳定性,位移跟踪误差和速度跟踪误差渐进收敛到零。利用Simulink进行仿真研究,仿真结果表明,该控制器可以显著地减小有摩擦结构在共振频率附近的响应,并改善系统在较高频率的隔振性能。

关键词：有摩擦结构 LuGre模型自适应控制 Skyhook参考模型双观测器振动控制

ZnO含量对Ag2O-CaO-Fe2O3-SiO2玻璃析晶的影响

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中国有色金属学报 2008年第3期18卷 489-493页

作者：李彬文丽华马臣湖州师范学院生命科学学院湖州313000 佳木斯大学生物医学材料省级重点实验室佳木斯154007

通过溶胶-凝胶法制备Ag2O-CaO-Fe2O3-SiO2系基础玻璃,采用晶化工艺制得该系抗菌微晶陶瓷,利用DSC、SEM和XRD等技术和动力学理论探讨该体系的晶化机理,计算不同ZnO含量的玻璃析晶活化能,研究ZnO含量变化对玻璃晶化的影响。结果表明:ZnO... 详细信息

通过溶胶-凝胶法制备Ag2O-CaO-Fe2O3-SiO2系基础玻璃,采用晶化工艺制得该系抗菌微晶陶瓷,利用DSC、SEM和XRD等技术和动力学理论探讨该体系的晶化机理,计算不同ZnO含量的玻璃析晶活化能,研究ZnO含量变化对玻璃晶化的影响。结果表明:ZnO含量对玻璃析晶影响显著,随着ZnO含量增加,玻璃析晶温度降低;当ZnO含量为5%时,玻璃的析晶活化能最低(E=324.522kJ/mol);ZnO的加入未改变玻璃原来的晶相,主晶相仍是磁铁矿和硅灰石,但晶体的生长方式略有改变。

关键词： Ag2O-CaO-Fe2O3-SiO2玻璃微晶陶瓷析晶活化能