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Asymmetric total syntheses of (+)-goniopypyrone and (+)-9-deoxygoniopypyrone

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Chinese Journal of chemistry 1996年第2期14卷 152-159页

作者： Yang, zc Zhou, WS CHINESE ACAD SCI SHANGHAI INST ORGAN CHEMSHANGHAI 200032PEOPLES R CHINA

Asymmetric total syntheses of (+)-goniopypyrone (1) and (+)-deoxygoniopypyrone (2) from methyl cinnamate (7) via (DHQ)(2)-PHAL-OsO4 catalyzed asymmetric dihydroxylation and highly stereoselective 2-furylcopper additio... 详细信息

关键词： asymmetric total synthesis goniopypyrone 9-deoxygoniopypyrone 2-furylcopper

Microstructure and Mechanical Properties of Al-4.9Ni-4.9Ti Alloy Prepared by Mechanical Alloying

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Journal of Materials Science & Technology 1995年第3期11卷 209-212页

作者： LIANG, GX LI, zc WANG, E Harbin Inst of Technology Harbin China

Mechanically alloyed Al-4.9Ni-4.9Ti powders were prepared by milling mixed aluminium, titanium and nickel powders, and then consolidated by hot hydrostatic extrusion. The microstructures of milled powders and extruded bars were characterized by X-ray diffraction and transmission electron microscopy observation. The results show that mechanical alloying and consolidating processes have great effects on the microstructures and mechanical properties of extruded materials. Polycrystalline materials having an ultrafine grain size may be prepared by mechanical alloying. The strength and thermal stability are improved with the increasing of processing time of mechanical alloying, since grain size decreases and volume fraction of dispersoids increases as milling time increased.

关键词： Aluminum alloys

A New Approach to the Construction of Pyrrolizidine and Indolizidine Skeleton: Enantioselective Synthesis of (1S, 7aS)-1-hydroxypyrrolizidine and (1S, 8aS)-1-hydroxyindolizidine

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Chinese chemical Letters 1997年第9期8卷 773-776页

作者： Dong, HQ Shi, zc Lin, GQ CHINESE ACAD SCI SHANGHAI INST ORGAN CHEMSHANGHAI 200032PEOPLES R CHINA

A new approach to the construction of pyrrolizidine and indolizidine skeleton was described. By employing this cyclization method the synthesis of (1S. 7aS)-1-hydroxypyrrolizidine (1a) and (1S. 8aS)-1-hydroxyindolizidine (1b) was achieved by treatment of the trimesylate 6a or 6b with aqueous ammonia in the presence of KaCO(3) (or Cs2CO3) in one-pot fashion.

关键词： ppm HRMS A New Approach to the Construction of Pyrrolizidine and Indolizidine Skeleton hydroxyindolizidine hydroxypyrrolizidine and Enantioselective Synthesis of

Electron transfer in phosphorylated peptide--Study of laser photolysis on N-dipp-TrpH-TyrOH peptide

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Chinese Journal of chemistry 1995年第4期13卷 324-333页

作者： WANG, ZY ZHANG, zc ZHANG, MW UNIV SCI & TECHNOL CHINA DEPT CHEM PHYSHEFEI 230026PEOPLES R CHINA CHINESE ACAD SCI SHANGHAI INST NUCL RESRADIAT CHEM LABSHANGHAI 201800PEOPLES R CHINA

The Laser photolysis of N-diisopropyl phosphoryl tryptophyl. tyrosine dipeptide methyl ester (N-DiPP-TrpH-TyrOH) has been carried out utilizing a KrF(248 nm) laser. The direct intramolecular ET between TrpH(+) residue and TyrOH residue was detected first and the ET between Trp. and TyrOH became dow. It was suggested that phosphoryl group stabilize neighbour radical of aromatic ring by hyperconjugation. In combination with computer modeling we obtained the kinetic parameters of the ET and proved that phosphoryl groups took part in the process of ET. The results should be significant for biological system since every biological process involves the phosphorylations or nonphosphorylation.

关键词： ELECTRON TRANSFER PHOSPHORYLATED PEPTIDE PHOTOLYSIS

A Novel Electrocatalysis Method for Organic Pollutants Degradation

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Chinese chemical Letters 2001年第10期12卷 929-932页

作者： Zhou, MH Wu, zc Wang, DH Zhejiang Univ Dept Environm Sci & Engn Hangzhou 310027 Peoples R China

A novel electrocatalysis, ferrous ion catalyzed anodic-cathodic electrocatalysis (FACEC), was developed for organic pollutants degradation, which could promote the degradation by achieving synergetic effects of both anodic oxidation and cathodic indirect oxidation. The degradation rate of model pollutants - phenol by FACEC could increase by nearly 30% comparing with that of anodic electrocatalysis, and the current efficiency could reach 67%.

关键词： electrocatalysis synergetic effect phenol degradation

Erosion Behaviour of TiNi Alloy Foils under Various Heat Treatments

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Journal of Materials Science & Technology 1996年第4期12卷 286-290页

作者： Liang, YN Wang, zc Li, SZ Si, ZY CHINESE ACAD SCI INST MET RESSHENYANG 110015PEOPLES R CHINA

The erosion behaviour of TiNi alloy foils (Ni: 50.5 at pct, thickness: 70-90 mu m) under various heat treatments has been studied with two different tests: sand-blasting erosion (SBE) with impingement angle of 30 degrees and slurry erosion (SE). The erosion resistance of the foils aged at 400-450 degrees C/30 min is the best in all tests. The quenched foil is also good in the SBE test, but not so good in the SE test. The slurry-erosion resistance of the aged foils is better than that of L214 with high hardness. All the foils exhibit much better erosion resistance than 18Cr-8Ni stainless steel in the tests.

关键词： Metal foil

Synthesis and Crystal Structure of Cupric Complex with Propylenebis(oxamic acid)

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Chinese Journal of Structural chemistry 1999年第2期18卷 56-60页

作者： Zhu, zc Xu, Z Huang, XY Nanjing Univ Inst Coordinat Chem State Key Lab Coordinat Chem Nanjing 210093 Peoples R China Chinese Acad Sci Fujian Inst Res Struct Matter State Key Lab Struct Chem Fujian 350002 Peoples R China

The violet red sheet like single crystals of dimeric complex K 2Cu(pba)·3H 2O) 2, where pba=propylenebis (oxamic acid), were prepared. Crystals are triclinic, molecular formula Cu 2K 4O 18 N 4C 14 H 24 , M r =819.84, space group P1, a=10.450(2), b=10.675(3), c=13.054(9) , α=107.04(5), β=100.21(6), γ=88.54(2)°, V=1370(1)  3, D x =1.99 g/cm 3 and Z=2. The structure was solved by direct methods with final R =0.050 and R w =0.066 for 3827 observed reflections with I>3σ(I) . Two nitrogen atoms and two oxygen atoms from the oxamide coordinate to the Cu Ⅱ atom forming a distorted square planar geometry.

关键词： dimeric complexes X ray structure copper complex

压应力激活SOST/Wnt/β-catenin 通路诱导软骨终板细胞退变

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中国组织工程研究 2025年第5期29卷 951-957页

作者：项攀车艳军罗宗平苏州大学附属第一医院骨科研究所江苏省苏州市215006 南京医科大学附属苏州医院骨科与运动医学中心江苏省苏州市215000

背景:在许多可以导致椎间盘退变的因素中(衰老、营养匮乏、机械因素等),力学负荷被认为是极其重要的因素,但其机制尚不清楚。目的:探讨硬骨素和Wnt/β-catenin信号通路在压应力诱导终板软骨退变中的作用。方法:提取4周龄雄性SD大鼠软骨... 详细信息

背景:在许多可以导致椎间盘退变的因素中(衰老、营养匮乏、机械因素等),力学负荷被认为是极其重要的因素,但其机制尚不清楚。目的:探讨硬骨素和Wnt/β-catenin信号通路在压应力诱导终板软骨退变中的作用。方法:提取4周龄雄性SD大鼠软骨终板细胞,体外利用力学加载仪器对终板软骨细胞施加压应力,于压缩细胞1,3,5,7 d,采用CCK-8法测定细胞活力;Western blot、RT-qPCR及细胞免疫荧光等检查终板软骨细胞内软骨标记物(聚集蛋白聚糖、Ⅱ型胶原)、钙化相关因子(Runx2、骨钙素)、细胞外基质降解酶及信号通路基因(硬骨素、β-catenin)等表达。结果与结论:①压应力作用下,终板软骨细胞活力会随着压应力时间、强度增加而降低;②终板软骨细胞的软骨标记物(聚集蛋白聚糖、Ⅱ型胶原)表达下降,而钙化相关因子(Runx2、骨钙素)表达上升;③压应力能促进终板软骨细胞的细胞外基质降解,基质金属蛋白酶3、基质金属蛋白酶13表达量增加;④细胞内Wnt/β-catenin信号通路表达出现异常,其特异性抑制因子硬骨素伴随着β-catenin的异常积累而表达下降。结果说明:在压应力作用下,终板软骨细胞内硬骨素的表达下降,导致Wnt/β-catenin信号通路激活,促进软骨终板的钙化、退变与细胞外基质的降解,进而促进椎间盘退变。

关键词：软骨终板软骨细胞 SOST Wnt/β-catenin 压应力椎间盘退变

Protective effect of early enteral feeding on postburn impairment of liver function and its mechanism in rats

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World Journal of Gastroenterology 2000年第1期6卷 79-83页

作者： Zhu L Yang zc Li A cheng DC Institute of Burn Research Southwest HospitalThird Military Medical UniversityChongqing 400038China Critical Care Department Peking Union Medical College Hospital(PUMCH)Chinese Academy of Medical science(CAMS)Beijing 100730China

AIM To study the protective effect of earlyenteral feeding(EEF)on the postburnimpairment of liver function and its *** Wistar rats with 30% of total bodysurface area(TBSA)full-thickness burn *** effects of EEF on the postburnchanges of gastric intramucosal pH,endotoxinlevels in portal vein,water contents of hepatictissue,blood concentrations of tumor necrosisfactor(TNF-α),plasma activities of alanineaminotransferase(ALT)and asparateaminotransferase(AST),as well as the bloodcontents of total(TB)and direct bilirubin(DB),total protein(TP)and albumin(ALB)wereserially determined within 48h *** EEF could significantly improvegastric mucosal acidosis,reduce portal veinendotoxin level and water content of hepatictissue,as well as plasma concentrations of TNF-α at all timepoints after severe burns(P<0.01);postburn elevation of the plasma activities ofALT,AST and the contents of TB,DB wereeffectively prevented,whereas the plasmaconcentrations of TP and ALB were markedlyincreased 24 h and 48 h posturn in EEF groupcompared with that of the burn without EEFgroup(P<0.01).CONCLUSION EEF has significant beneficialeffects on the improvement of hepatic function in rats after severe burn,and is probably relatedwith an increase in splanchnic blood flow,reduction of the absorption of gut-originendotoxin and the consequent release ofinflammatory mediators.

关键词： Subject headings early enteral feeding liver postburn impairments