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n-Butyl Pyridinium Nitrate as a Reusable Ionic Liquid Medium for Knoevenagel Condensation

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Chinese Chemical Letters 2003年第5期14卷 448-450页

作者： Yi Qun LI xin ming xu Mei Yun ZHOU Department of Chemistry Jinan UniversityGuangzhou 510632

The Knoevenagel condensation of carbonyl substrates with active methylene compounds proceeds smoothly with ammonium acetate as catalyst in n-butyl pyridinium nitrate to afford the desired products of good purity in mo... 详细信息

关键词： n-Butyl pyridinium nitrate ionic liquid Knoevenagel condensation.

Visible-light induced cascade radical cyclization of sulfinic acids and o-(allyloxy)arylaldehydes towards functionalized chroman-4-ones

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Chinese Chemical Letters 2020年第12期31卷 3255-3258页

作者： Guang-Hui Li Qing-Qing Han Yuan-Yuan Sun De-Mao Chen Zu-Li Wang xin-ming xu Xian-Yong Yu College of Chemistry and Pharmaceutical Sciences Qingdao Agricultural UniversityQingda 266109China College of Chemistry and Chermical Engineering Yantai UniversityYantai 264005China School of Chernistry and Chemical Engineering Hunan UIniversity of Science and TechnologyXiangtan 411201China

An efficient method for the synthesis of functionalized chroman-4-ones induced by visible light via the radical cyclization reaction of sulfinic acids and o-(allyloxy)arylaldehydes at room temperature was *** corresponding products were isolated with moderate to good *** mechanism was proposed fo r this trans ***-microbial activity of some desired compounds we re screened.

关键词： Visible light Sulfinic acids Radical cyclization Chroman-4-one o-(Allyloxy)arylaldehydes

Chemokine stromal cell-derived factor 1/CXCL12 increases homing of mesenchymal stem cells to injured myocardium and neovascularization following myocardial infarction

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Chinese Medical Journal 2009年第2期122卷 183-187页

作者： ZHUANG Yu CHEN xin xu ming ZHANG Lei-yang XIANG Fei Department of Thoracic and Cardiovascular Surgery Nanjing First Hospital Affiliated to Nanjing Medical University Nanjing Jiangsu 210006 China

Background Heart failure due to ischemic heart disease is still a major health problem. Myocardium regeneration emerges as a novel therapeutic method for treating myocardial infarction （MI）. However, it is affected by many factors. The present study was aimed to investigate the effect of chemokine stromal cell-derived factor 1 （SDF-1）/CXCL12 on mesenchymal stem cells （MSCs） homing to injured myocardium in a rat myocardial infarction model. Methods A rat myocardial infarction model was established by permanent left anterior descending branch ligation. Mesenchymal stem cells from donor rats were cultured in IMDM and labeled with bromodeoxyuridine. The rats were divided into two groups. SDF-1 expression was measured by in situ hybridization and immunohistochemistry in the sham operated or infarcted hearts at 1, 2, 4, 7, 14 and 28 days post operation in the SDF-1 detection group. The rats in the intervention groups were injected with SDF-1, anti-SDF-1 antibody or saline 4 days after myocardial infarction. Then, a total of 5×10^6 cells in 2.5 ml of phosphate-buffered saline were injected through the tail vein. The number of the labeled MSCs in the infarcted hearts was counted on the 3rd day post injection. Cardiac function and blood vessel density were assessed on the 28th day post injection. Results Self-generating SDF-1 expression was increased at the first day post MI, peaked at the 7th day and decreased thereafter while it remained unchanged in sham operated hearts. The MSCs enrichment in the host hearts were more abundant in the MI groups than in the non-MI group （P=0.000）; the MSCs enrichment in the host hearts were more abundant in the SDF-1 injected group than in the anti-SDF-1 antibody and saline injected groups （P = 0.000）. Cardiac function was improved more in the SDF-1 injected group than in the anti-SDF-1 antibody and saline injected groups （P = 0.000）. Neovascularization in the SDF-1 injected group increased significantly compared to the other groups （P= 0.

关键词： mesenchymal stem cells homing behavior myocardial infarction chemokine CXCL12

Experimental Research on Residual Stress in Surface of Silicon Nitride Ceramic Balls

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厦门大学学报（自然科学版） 2002年第S1期41卷 41-42页

作者： REN Cheng-zu, WANG Tai-yong, JIN xin-ming, xu Hao (Institute of Mechanical Engineering, Tianjin University, Tianjin 300072, China)

The influence of the residual stress in surface of ceramic balls on the fatigue life is large, because the life of silicon nitride ball bearings is more sensitive to the load acted on the bearings than the life of all-steel ball bearings. In this paper, the influence of thermal stress produced in sintering and mechanical stress formed in lapping process on residual stress in surface of silicon nitride ceramic balls was discussed. The residual compress stress will be formed in the surface of silicon nitride ceramic balls after sintering. The residual tensile stress will be formed in surface of silicon nitride ceramic balls in lapping process, and the size of abrasive particle is smaller, such trend is stronger. In this paper the residual stress was measured by the xylometric measurement in which the material in surface was peeled with lapping. The distribution of residual stress in surface can be calculated with the variation in specific volume. The technological parameter with which the material was peeled by lapping was given, for minimizing the extra influence of the residual stress forming in peeling on the original residual stress in surface, the abrasive particle size would not be too small and the load impressed would not be too large. Some experimental researches on residual stress in surface of silicon nitride ceramic balls were made. The surface of silicon nitride ceramic balls presented residual compressive stress after sintering and the influence of the ball size on the residual stress is feeble. It is expected that the size of ball blank is same for achieving the same residual compressive stress in surface on balls after final machining. In lapping process, the surface of silicon nitride ceramic balls presented residual tensile stress, the larger the load which is impressed on single ball, the larger the amplitude of residual tensile stress is; the smaller the abrasive particle, the stronger the trend of plastic deformation is and the larger the amplitud

关键词： silicon nitride ceramic balls residual stress xylometric measurement specific volume

Is the use of cardiopulmonary bypass for isolated coronary artery bypass an independent predictor of mortality and morbidity in patients with severe left ventricular dysfunction？

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Chinese Medical Journal 2008年第23期121卷 2397-2402页

作者： QIU Zhi-bing CHEN xin xu ming SHI Kai-hu JIANG Yin-shuo XIAO Li-qiong Department of Cardiothoracic Surgery Nanjing First Hospital Affiliated to Nanjing Medical University Nanjing Heart Institute Nanjing Jiangsu 210006 China

Background Patients presenting with severe left ventricular dysfunction （SLVD） undergoing conventional coronary artery bypass grafting （CCABG） are at an increased risk of perioperative mortality and morbidity. The aim of this study was to assess the risk factors responsible for mortality and morbidity among patients with SLVD by comparing CCABG and oft-pump coronary artery bypass surgery （OPCAB）. Methods We retrospectively evaluated 186 consecutive patients with SLVD who underwent coronary artery bypass grafting （CABG）, including 102 by CCABG and 84 by OPCAB. Registry database, medical notes, and charts were studied for preoperative and postoperative data of the patients. Different variables and risk factors （preoperative, intraoperative, and postoperative） were evaluated and compared. The morbidity and mortality outcomes were compared in the two groups. The follow-up results and quality of life were assessed after surgery. Results The two groups had similar percentage of patients with preoperative high-risk profiles and no significant differences were found between groups in baseline variables such as age or comorbidities. There was a significant difference in the number of grafts used between the two groups. CCABG patients received （3.6±0.5） grafts per patient, while OPCAB patients had （2.7±0.6） grafts （P 〈0.05）. Completeness of revascularization was also significantly different between the two groups （CCABG 91.1% vs OPCAB 73.8%, P 〈0.05）. The hospital mortality was similar in the two groups （4.8% in OPCAB vs 5.9% in CCABG）. The risk-adjusted mortality, according to the calculated propensity score, did not reach statistical significance in the two groups. In this study, OPCAB seemed to have a beneficial effect on reducing reoperation for bleeding, blood transfusion requirement, and the length of stay at ICU. But the incidence of perioperative myocardial infarction was more common in the off-pump group （P 〈0.05）. The degree of improvement in angina and quality

关键词： coronary artery bypass, off-pump cardiopulmonary bypass left ventricular dysfunction

Off-pump versus on-pump coronary artery bypass surgery for the treatment of left main with triple coronary artery disease

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Journal of Nanjing Medical University 2008年第3期22卷 159-163页

作者： Zhibing Qiu xin Chen ming xu Kaihu Shi Yinshuo Jiang Liqiong Xiao Department of Cardiothoracic Surgery the Nanjing First Hospital Affiliated to Nanjing Medical University Nanjing 210006 Jiangsu Province China

Objective：To obtain early results of off-pump coronarE~ artery bypass grafting（OPCAB） in patients with significant left main coronary artery（LMCA） and triple vessels stenosis by comparing with those of a similar group undergoing conventional coronary artery bypass surgery（CCAB）. Methods：Data for patients with significant LMCA and triple vessels stenosis who underwent CCAB or OPCAB were collected retrospectively between January 1999 and May 2006. Non-randomized, retrospective data analysis included demo- graphic and preoperative risk factors, operative details, clinical outcome and early follow-up. Results： The number of distal anastomo- sis and grafts varied from 3 to 6. The average number per patient was similar in the two groups （OPCAB group：3.76 ± 0.98, CCAB group：3.81 ± 1.02）. Thirty-day mortality occurred to one patient in the OPCAB group whereas two early deaths were observed in the CCAB group but did not reach statistical significance （P 〉 0.05）. The frequency of atrial fibrillation （AF）, IABP usage, mediastinitis, re-operation for bleeding （or tamponade） were similar in the two groups （P 〉 0.05）. Postoperative inotropic requirements, peak CKMB, ventilation time, blood loss, FFP, RBC transfusion need and the length of ICU-stay were all significantly lower in the OPCAB group compared with CCAB group（P 〈 0.05）.Conclusion： Significant LMCA and triple-vessel stenosis can safely and effectively undergo myocardial revascularization using OPCAB surgery. LMCA should no longer be seen as a contraindication to perform OPCAB grafting.

关键词： left main coronary artery triple-vessel stenosis off-pump coronary artery bypass grafting

Comparative study of graft flow between on-pump and off-pump coronary bypass surgery for patients with multivessel coronary artery disease

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Journal of Nanjing Medical University 2006年第6期20卷 351-354页

作者： xin Chen ming xu Zhibing Qiu Yinshuo Jiang Liming Wang Liqiong Xiao Department of Thoractic ＆ cardiovascular surgery the First Hospital Afficiated to Nanjing Medicul University Nanjing Heart Institue Nanjing 210006 China

Objective： To Comparatively study grafts flow between on-pump and off-pump coronary bypass surgery for patients with triple coronary artery disease. Methods ： The grafts flow was studied in 100 patients of OPCAB and compared with 100 cases of CCABG by means of Medi-Stim Butterfly Flowmeter measurement intraoperatively. Results： The mean number of the distal anastomosis was 3.78＋ 1.11 in CCABG group, and 3.83 ＋ 0.93 in OPCAB group. The index of completeness of revascularization in CCABG group was 1.01 ＋ 0.08, and 1.10＋ 0.09 in OPCAB group. The flow of grafts was satisfied in all patients. The PI values were all under 5. There was no significant difference in the mean graft flow and PI value between two groups. Conclusion： OPCAB can provide the same grafts flow and similar completeness of revascularization when compared with CCABG which indicates the similar anastomosis quality of grafts in OPCAB and CCABG groups.

关键词： off-pump coronary artery bypass grafting flow of grafts revascularization

Catalytic Asymmetric Tandem Reaction of Tertiary Enamides:Expeditious Synthesis of Pyrrolo[2,1-a]isoquinoline Alkaloid Derivatives

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Catalytic Asymmetric Tandem Reaction of Tertiary Enamides:Ex...

Novel Bis-(N-alkyl-N ,N-dimethyl-ammonium) Polyethyleneglycol Ether Salts as Phase Transfer Catalysts in the Condensation of l,4-Diacetyl-2,5-piperazinedione and Aldehydes

中国化学会第十三届全国有机合成化学学术研讨会

作者： xin-ming xu Liang Zhao Jieping Zhu Wang Mei-Xiang Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology（Ministry of Education） Department of Chemistry Tsinghua University

Hexahydropyrrolo[2,1-a]isoquinoline and tetrahydropyrrolo[2,1-a]isoquinolin-3（2 H）-one structures occur widely in natural products,which display remarkable antitumor,antibacterial,antiviral,and antioxidizing *** of unique fused heterocyclic ring structures and diverse pharmacological activities,these alkaloids are very popular and attractive targets for synthetic organic *** de novo construction of hexahydropyrrolo[2,1-a]isoquinoline and tetrahydropyrrolo[2,1-a]isoquinolin-3（2 H）-one structures in catalytic enantioselective manner is not *** we reported a new and efficient strategy for rapid construction of the chiral tetrahydropyrrolo[2,1-a]isoquinolin-3（2 H）-one structure from unique tertiary enamide synthons.A Cu（OTf）2/chiral Pybox complex catalyzes the intramolecular enantioselective addition of tertiary enamides to ketonic carbonyls with subsequent diastereoselective interception of the resulting acyliminium by tethered electron-rich aryl *** tandem reaction produces diverse tetrahydropyrrolo[2,1-a]isoquinolin-3（2 H）-one derivatives as the sole diastereoisomers in good to excellent yields with up to 98.5%*** transformations of the resulting heterocycles into various hexahydropyrrolo[2,1-a]isoquinoline derivatives were also demonstrated.

关键词： alkaloids asymmetric catalysis copper cyclization synthetic methods

来源： cnki会议评论

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Chemical Research in Chinese Universities 1995年第2期11卷 178-184页

作者： WANG Li-xin,xu ming-hua,SHI Yao-zcng and HU Hong-wen (Department of Chemistry,Nanjing University,Nanjing,210008) resent address Chengdu Institute of Organic Chemistry,Acdemia Sinica,Chengdu,610015 Present address:Chengdu lnstutute of Organic Chentistry Acdemia Simca.Chengdu,G10015 NANJING UNIV DEPT CHEMNANJING 210008PEOPLES R CHINA

Phase transfer catalysis (PTC) has become one of the most extensively used techniques in organic synthesis. The key factor in such processes is the catalyst. There are mainly two kinds of phase transfer catalysts, one is the so called "crown ethers" including macrocyeles, open chain molecules with long chains, bearing heteroatoms at a proper distance, and can chelate inorganic

关键词： Phase transfer catalysis 2 5-Piperazincdione Selectivity