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Preparation of amphiphilic graft copolymer with polyisoprene backbone by combination of anionic polymerization and "click" reaction

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Chinese Chemical Letters 2012年第3期23卷 347-350页

作者： Fei Shao xu feng ni Zhi Quan Shen MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

A novel graft copolymer consisting of polyisoprene backbone and hydrophilic side chain with carbamic acid ester functional group was prepared via thiol-ene＂click＂reaction and alcohol-isocyanate *** was synthesized by anionic polymerization using n-butyl lithium as initiator,and the pendant hydroxyl groups were introduced by the thiol-ene reaction of mercaptoethanol with the double bond of 1,2-addition units of PI backbone in the presence of radical initiator azobisisobutyronitrile. Isocyanate end group capped poly（ethylene glycol）（mPEG-NCO） was grafted onto the PI backbone through alcoholisocyanate reaction between the pendant hydroxyl groups and isocyanate group of *** structure of the graft copolymer were characterized and confirmed by means of size-exclusion chromatography,~1H NMR and FTIR spectroscopy.

关键词： Graft-copolymer Thiol-ene addition Isocyanate Click reaction

Mechanism of Janus Polymerization: A DFT StudyFig. S3 Energy profiles of anionic polymerization in Stage I under B3LYP/6-31G(d,p)(blue) and B3LYP/aug-cc-p VTZ//B3LYP/6-31G(d,p)(red). Scheme S1. Propagation process of CL/THF on cationic side in Stage I of J

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Chinese Journal of Polymer Science 2019年第10期37卷 990-994,I0004页

作者： Tian-Wen Bai xu-feng ni Jun Ling Zhi-Quan Shen Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University

Janus polymerization is featured as a combination of cationic and anionic growing ends in one living polymer chain. In the copolymerization of THF and CL catalyzed by lutetium triflates and initiated by propylene oxide, three stages are identified by kinetic study including(1) fast cationic polymerization with slow anionic one,(2) fast anionic polymerization with dormant cationic one, and(3)reactivation of cationic polymerization with coupling of anionic and cationic chain ends. In this work, density functional theory(DFT)calculation is employed to investigate the reaction details of ionic polymerization and dormancy. A “tripedal crow” configuration is proposed to illustrate the unique high-coordinated ligand exchange configuration in anionic polymerization in different stages. The trigger of dormancy is determined as chain structures rather than concentration of triflate anion according to both calculation and experimental results.

关键词： Rare earth metal catalysts Ring-opening polymerization Ionic polymerization Reaction mechanism Quantum chemicalcomputation

Polymerization of isoprene catalyzed by neodymium heterocyclic Schiff base complex

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Chinese Chemical Letters 2008年第6期19卷 734-738页

作者： Lei Zhang xu feng ni Wei Lin Sun Zhi Quan Shen Institute of Polymer Science Key Laboratory of Macromolecule Synthesis and Functionalization Ministry of Education Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China

Neodymium-based heterocyclic Schiff base complex was prepared and applied for the coordination polymerization of isoprene. This complex polymerized isoprene to afford products featuring high cis-1,4 stereospecificity （ca. 95%） and high molecular weight （ca, 10^5） in the presence of the triisobutyl aluminium （AliBu3） as cocatalyst, The microstructure of obtained polyisoprene was investigated by FTIR, 1^H NMR. Two different kinds of active centers in the catalyst system were examined by GPC method.

关键词： Heterocyclic Schiff base Neodymium complex Isoprene Coordination polymerization

Synthesis,characterization of neodymium chloride complex of amine-bis(phenolate) ligand and its reactivity in the ring-opening polymerization of ε-caprolactone

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Chinese Chemical Letters 2011年第2期22卷 249-252页

作者： Li Rong Wang Zhen Hua Liang xu feng ni Zhi Quan Shen MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China Received 4 June 2010

The neodymium chloride complex[Nd（ONN＇O）Cl（THF）]2 supported by amine-bis（phenolate） ligand was synthesized by the metathesis reaction of anhydrous NdCl3 with Li2（ONN＇O）[H2ONN＇O = Me2NCH2CH2N（CH2-3-Bu2^t-5-Me-C6H2OH）2]in high yield.X-ray structural determination shows[Nd（ONN＇O）Cl（THF）]2 complex consists of two seven-coordinate neodymium centers linked throughμ-Cl *** this complex was successfully used to initiate the ring-opening polymerization（ROP） ofε-caprolactone.

关键词： Amine-bis(phenolate) complex Rare earth catalyst X-ray crystallography ε-Caprolactone

Tetrahydrosalen backboned gadolinium complex as initiator for the ring-opening polymerization of ε-caprolactone

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Chinese Chemical Letters 2008年第6期19卷 681-684页

作者： Guang Ming Wu xu feng ni Wei Lin Sun Zhi Quan Shen Key Laboratory of Maeromoleeule Synthesis and Functionalization Ministry of Education Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China

Tetrahydrosalen ligand was employed in the synthesis of gadolinium complex. The ligand was deprotoned by LiBu, and the afforded lithium salt was reacted with anhydrous GdCl3 to produce the gadolinium complex through salt metathesis. This complex was successfully used to initiate the ring-opening polymerization of ε-caprolactone. The initiation conditions in different temperature, monomer-to-initiator ratio and time were investigated. Under the condition： [ε-caprolactone]：[catalyst] = 600, 56 ℃, toluene： 2 ml, poly（ε-caprolactone）（PCL） with Mw = 11,2782 and PDI = 1.96 was achieved.

关键词： Tetrahydrosalen complex Rare earth catalyst ε-Caprolactone Ring-opening polymerization

Effect of Bixieqianggupian on experimental osteoporosis in rats

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沈阳药科大学学报 2008年第S1期25卷 124-125页

作者： YU Yao-hong,xu feng,LI ni,ZHOU xue-ting(Shenyang Pharmaceutical University,Shenyang 110016,China)

Objective To search the effects of Bixieqianggupian(BXQBP)on *** The experimental models of osteoporosis(OP)induced by ovariectomy(OVX),retinoic acid(RA)and dexamethasone(DXM)in rats were introduced in this *** the same time,the influence on tibia fracture healing in rats was also ***,the anti-inflammation effects and analgesia of BXQBP in mice and rats were also *** The body weight gain induced by OVX was prevented obviously by administering *** serum estradiol and bone gla protein(BGP)were examined by RIA,and results showed that estradiol increased and BGP *** mineral density(BMD),bone mineral content(BMC)and bone mass of femur had increased,moreover,calcium content of bone(monitored by atomic absorption)had been improved significantly after BXQBP ***,biomechanical characters of bone were measured by three point bending test,and the anti-bend intensity and maximum bend strength increased *** alkaline phosphatese(ALP)*** amount of urine calcium(Ca)and hydroxyproline(HOP)decreased ***,effect on the proliferation of endometria was not *** RA induced OP *** with model,the BMD and BMC increased markedly in BXQBP rats(i.g.30 days).And bone mass and calcium content were *** BGP and ALP decreased by administering *** anti-band intensity and maximum bend strength increased *** ejection of urine Ca and HOP decreased *** bone trabecula became thinner,and arranged in disorder in OP rats,however,the status was reversed obviously by administrating *** OP model also induced by DXM in rats:Effect against weight losing caused by DXM was observed in groups of three doses(i.g.12 weeks)of *** BMD,BMC,bone mass and calcium content increased *** results showed that the fracture healing had been enhanced obviously at three doses(i.g.40 days),callus growth was promoted and bone rigidity was

关键词： bixieqianggupian osteoporosis

Fascin promotes the motility and invasiveness of pancreatic cancer cells

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World Journal of Gastroenterology 2011年第40期17卷 4470-4478页

作者： Yan-feng xu Shuang-ni Yu Zhao-Hui Lu Jian-Ping Liu Jie Chen Department of Pathology Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Tsinghua University Beijing 100730 China

AIM:To explore the role of actin-bundling protein, fascin during the progression of pancreatic cancer. METHODS:The plasmid expressing human fascin-1 was stably transfected into the pancreatic cancer cell line MIA PaCa-2. The proliferation, cell cycle, motility, scattering, invasiveness and organization of the actin filament system in fascin-transfected MIA PaCa-2 cells and control non-transfected cells were determined. RESULTS:Heterogeneous overexpression of fascin markedly enhanced the motility, scattering, and inva-siveness of MIA PaCa-2 cells. However, overexpression of fascin had minimal effect on MIA PaCa-2 cell pro-liferation and cell cycle. In addition, cell morphology and organization of the actin filament system were distinctly altered in fascin overexpressed cells. When transplanted into BALB/c-nu mice, fascin-transfected pancreatic cancer cells developed solid tumors at a slightly slower rate, but these tumors displayed more aggressive behavior in comparison with control tumors. CONCLUSION: Fascin promotes pancreatic cancer cell migration, invasion and scattering, thus contributes to the aggressive behavior of pancreatic cancer cells.

关键词： Fascin Invasiveness Motility Pancreaticcancer

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稀土催化的开环聚合研究进展

高分子学报 2021年第5期52卷 445-455页

作者：沈婷倪旭峰凌君教育部高分子合成与功能构造重点实验室浙江大学高分子科学与工程学系杭州310027

稀土催化剂在开环聚合中表现出极高的催化活性,本文总结了近十年来稀土催化剂在内酯、交酯、环醚、环碳酸酯、环羧酸酐等单体开环聚合中的应用,结合催化剂结构与聚合效果总结了稀土催化剂在聚合过程可控和聚合物结构控制方面的独特优势... 详细信息

稀土催化剂在开环聚合中表现出极高的催化活性,本文总结了近十年来稀土催化剂在内酯、交酯、环醚、环碳酸酯、环羧酸酐等单体开环聚合中的应用,结合催化剂结构与聚合效果总结了稀土催化剂在聚合过程可控和聚合物结构控制方面的独特优势,并介绍了稀土催化的新型开环聚合方法.

关键词：稀土催化剂开环聚合立构控制聚酯聚醚聚碳酸酯聚氨基酸两仪聚合

Effect of multiple-phase regional intra-arterial infusion chemotherapy on patients with resectable pancreatic head adenocarcinoma

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Chinese Medical Journal 2009年第3期122卷 284-290页

作者： JIN Chen YAO Lie LONG Jiang FU De-liang YU Xian-jun xu Jin YANG feng ni Quan-xing Pancreatic Disease Institution Department of General SurgeryHuashan Hospital Fudan University Shanghai 200040 China

Background Regional intra-arterial infusion chemotherapy （RIAC） has been more valuable to improve prognosis and quality of life of patients with inoperable pancreatic adenocarcinomas, and adjuvant RIAC plays an important role in prolonging survival and reducing risk of liver metastasis after radical resection of pancreatic cancer, but the effect of preoperative or multiple-phase RIAC （preoperative combined with postoperative RIAC） for resectable pancreatic cancers has not been investigated. In this prospective study, the effect of multiple-phase RIAC for patients with resectable pancreatic head adenocarcinoma was evaluated, and its safety and validity comparing with postoperative RIAC were also assessed. Methods Patients with resectable pancreatic head cancer were randomly assigned to two groups. Patients in group A （n=-50） were treated with new therapeutic mode of extended pancreaticoduodenectomy combined with multiple-phase RIAC, and those in group B （n=-50） were treated with extended pancreaticoduodenectomy combined with postoperative RIAC in the same period. The feasibility, compliance and efficiency of the new therapeutic mode were evaluated by tumor size, serum tumor markers, clinical benefit response （CBR）, surgical complications, mortality and toxicity of RIAC. The disease-free survival time, median survival time, incidence of liver metastasis, survival rate at 1, 2, 3 and 5 years were also observed. Life curves were generated by the Kaplan-Meier method. Results The pain relief rate and CBR in group A was 80% and 84% respectively. Serum tumor markers decreased obviously and tumors size decreased in 26% of patients after preoperative RIAC in group A. No more surgical complications, mortality or severe systemic side effects were observed in group A compared with group B. The incidence of liver metastasis in group A was 34% which was lower than 50% in group B. The disease-free survival time and median survival time in group A were 15.5 months and 18 months resp

关键词： pancreatic adenocarcinoma, neoadjuvant chemotherapy, multiple-phase intra-arterial infusion chemotherapy