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Chemical Research in Chinese Universities 2009年第5期25卷 673-676页

作者： WU Yi TENG Guo-sheng LIANG Yong-tao ZHONG da.fang LIU Bing College of Pharmacy Jilin University Changchun 130021 P. R. China College of Life Science Jilin University Changchun 130012 P. R. China School of Chemistry and Life Science Changchun University of Technology Changchun 130012 P. R. China Jilin Provincial Corps Hospital Chinese People＇s Armed Police Forces Changchun 130052 P. R. China

A simple, rapid and sensitive method for the determination of protopanaxadiol in rat plasma with ginsenoside Rh2 as internal standa.d was developed and valida.ed. The analyte and internal standa.d were extracted from plasma with ether-dichloromethane（3：2, volume ratio） and then were analyzed by reversed-phase HPLC on a short Zorbax Extend C18 column（50 mm×2.1 mm, 3.5 μm i. d.） eluted with a mobile phase consisting of acetonitrile/methanol 0.10 mmol/L ammonium acetate（45：45：10, volume ratio） at 0.4 mL/min. Detection was performed on an Applied Biosystems Sciex API 4000 mass spectrometer set at unit resolution in the multiple reaction monitoring mode. Electrospray ionization was used for ion production. The assay method shows linear over a range of 5-2000 ng/mL and intra- and inter-da. precisions over this range were 〈10.0% with accuracy ranged from 86.3% to 114.1%. The limit of detection was 500 pg/mL in the plasma. The method was successfully applied to a preclinical pharmacokinetic study of protopanaxadiol（17.5 mg/kg） administered as a single oral dose.

关键词： Protopanaxadiol Ginsenoside Rh2 LC/MS

A novel gain of function mutant in C-kit gene and its tumorigenesis in nude mice

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World Journal of Gastroenterology 2005年第45期11卷 7104-7108页

作者： Chen-Guang Bai Xiao-Hong Liu Qiang xie Fei Feng da.Lie Ma Departmentof Pathology Changhai Hospital Second Military MedicalUniversity Shanghai 200433 China Institute of Thoracic Cardiac Surgery ChanghaiHospital Second Military Medical University Shanghai 200433China

AIM： To transfect mutant C-kit cDNA at codon 579 into human embryonic kidney cell line to observe its role in the pathogenesis of gastrointestinal stromal tumor （GIST）. METHODS： Eukaryotic expression vectors of pcDNA3- Kit-NW and pcDNA3-Kit-W were constructed. Then pcDNA3-Kit-NW and pcDNA3-Kit-W plasrnids were transfected into human embryonic kidney cell line by Upofectamine. The resistant clone was screened by G418 filtration and identified by sequencing, Western blotting, and immunocytochemical staining. Human embryonic kidney cells were divided into three groups including pcDNA3-Kit-NW, pcDNA3-Kit-W, and vector control groups. Absorbency value with a wavelength of 574 nm was detected by MTT analysis. Mice were injected with three groups of cells. Volume, mass, and histological examinations of the tumors in different groups were measured and compared. RESULTS： The C-kit gene and mutant C-kit gene were successfully cloned into the eukaryotic expression vector pcDNA3, pcDNA3-Kit-NW and pcDNA3-Kit-W were successfully transfected into human embryonic kidney cell line and showed stable expression in this cell line. Cell proliferating activity had significant differences between pcDNA3-Kit-NW and pcDNA3, pcDNA3-Kit- NW and pcDNA3-Kit-W （P〈0.05）, respectively. Tumors were only observed in nude mice implanted with cells transfected with pcDNA3-Kit-NW. CONCLUSION： Mutation of C-kit gene increases the proliferation activity of human cells and plays an important role in the malignant transformation of GIST.

关键词： Gastrointestinal stromal tumors ProtooncogeneC-kit Gene mutation Malignant transformation

A Novel Self-Synchronization Scheme Based on Cross Gain Modulation and Self-Frequency Shift in an SOA

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The Journal of China Universities of Posts and Telecommunications 2006年第1期13卷 67-70,83页

作者： YE Xiao-hua ZHANG Fang-di ZHANG Min ZHANG Rui YE Pei-da Key Laboratory of Optical Communication and Lightwave Technologies Beijing University of Po~ts and Telecommunications Beijing 100876 P.R. China

This paper presents a novel self-synchronization scheme utilizing a semiconductor optical amplifier and an optical band-pass filter. Implemented using cross gain modulation and self frequency shift, the proposed scheme has a simple structure that does not need any special marker pulses. With proper tuning of semiconductor optical amplifier and optical band-pass filter parameters and delay time of the control pulse, we, through simulation, obtain a synchronization clock with the intensity contrast ratio of more than 20 dB from RZ pseudorandom bit sequence at different operation speeds.

关键词： optical packet networks self-synchronization SOA FS CR

A general, rapid and solvent-free approach to fabricating nanostructured polymer surfaces

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Science China(Technological Sciences) 2014年第12期57卷 2328-2334页

作者： TIAN Wei HUANG Long Biao WANG da.Wei Roy V. A. L. Key Laboratory of Space Applied Physics and Chemistry Ministry of Education and Shaanxi Key Laboratory of Macromolecular Science and Technology School of Science Northwestern Polytechnical University Center of Super-Diamond and Advanced Films (COSda.) and Department of Physics and Materials ScienceCity University of Hong Kong School of Chemistry and Chemical Engineering and Lehn Institute of Functional Materials Sun Yat-Sen University

A general, rapid and solvent-free approach is proposed to fabricate nanostructured polymer surfaces by coupling ultrasonic vi- bration and anodized aluminum oxide templating. With our approach, hollow nanorods or nanofibers with controlled diameter and length are prepared on polymer surfaces. The whole fabrication process is completed in ～30 s and equally applicable to polymers of different crystalline structures. The wettability of the as-fabricated polymer surfaces （being hydrophilic, hydro- phobic, highly hydrophobic or even superhydrophobic） is readily regulated by adjusting the welding time from 0 s to a maxi- mum of 10 s. Our approach can be a promising industrial basis for manufacturing functional nanomaterials in the fields of electronics, optics, sensors, biology, medicine, coating, or fluidic technologies.

关键词： nanomaterials nanostructured polymer surfaces ultrasonic vibration anodized aluminum oxide template wettability

Periodic Solutions to KdV-Burgers-Kuramoto Equation

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Communications in Theoretical Physics 2006年第5期45卷 815-818页

作者： JIANG Lei CHEN Xi FU Zun-Tao LIU Shi-Kuo LIU Shi-da School of Physics Peking University Beijing 100871 China State Key Laboratory for Turbulence and Complex Systems Peking University Beijing 100871 China

In this paper, a new special ansatz solution, where elliptic equation satisfied by elliptic functions is fallen as an intermediate transformation, is applied to solve the KdV-Burgers-Kuramoto equation, and many morenew periodic solutions are obtadned, including solutions expressed in terms of Jacobi elliptic functions, solution expressed in terms of Weierstrass elliptic function.

关键词： elliptic equation Jacobi elliptic function Weierstrass elliptic function KdV-Burgers-Kuramoto equation

Polyethylenimine-cyclodextrin-tegafur conjugate shows anti-cancer activity and a potential for gene delivery

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第9期12卷 720-729页

作者： Qi-da.HU Hui FAN Wei-jian LOU Qing-qing WANG Gu-ping TANG Institute of Chemical Biology and Pharmaceutical Chemistry Zhejiang UniversityHangzhou 310028China Department of Pharmacy Sir Run Run Shaw HospitalSchool of MedicineZhejiang UniversityHangzhou 310016China Institute of Immunology Zhejiang UniversityHangzhou 310058China The First Affiliated Hospital School of MedicineZhejiang UniversityHangzhou 310003China

Polyethylenimine-cyclodextrin-tegafur(PEI-CyD-tegafur) conjugate was synthesized as a novel multifunctional prodrug of tegafur for co-delivery of chemotherapeutic agent tegafur and enhanced green fluorescent protein(EGFP) reporter plasmid *** of tegafur to PEI-CyD via chemical linkage was characterized by 1 H NMR spectrometry and ultraviolet(UV) ***-CyD-tegafur was able to condense plasmid DNA into complexes of around 150 nm with positive charge at the N/P ratio of 25,in accorda.ce with electron microscopy observation of compact and monodisperse *** results of in vitro experiments showed enhanced cytotoxicity and considerable transfection efficiency in B16F10 cell ***,PEI-CyD-tegafur may have great potential as a co-delivery system with anti-cancer activity and potential for gene delivery.

关键词： Polyethylenimine β-Cyclodextrin Tegafur Co-delivery Gene therapy

Antidiabetic and haematological effect of aqueous extract of stem bark of Afzelia africana(Smith) on streptozotocin-induced diabetic Wistar rats

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Asian Pacific Journal of Tropical Biomedicine 2011年第5期1卷 353-358页

作者： Oyedemi SO Adewusi EA Aiyegoro OA Akinpelu da School of Biological Sciences University of Fort Hare Department of Microbiology Obafemi Awolowo University

Objective:To investigate the antidiabetic properties of aqueous extract of stem bark of Afzelia africana(***)and its beneficial effect on haematological parameters in streptozotocin induced diabetic ***:A total of 30 rats including 24 diabetic and 6 normal rats were used for this *** was induced in male Wistar rats by intraperitoneal injection of *** being confirmed diabetic,animals were orally treated with distilled water or extracts at 100 or 200 mg/kg body weight da.ly for 10 *** haematological parameters including red blood and white blood cells and their functional indices were evaluated in diabetic treated groups compared with the ***:The extract significantly reduced the blood glucose levels while the best result was obtained at 200 mg/kg body weight The feed and water intake in diabetic rats were significantly reduced while weight loss was minimized at both ***,the levels of red blood,white blood cells and their functional indices were significantly improved after extract administration at both ***:It can be concluded that the aqueous extract of bark of *** possesses antihyperglycemic *** addition,the extract can prevent various complications of diabetes and improve some haematological *** experimental investigation is needed to exploit its relevant therapeutic effect to substantiate its ethnomedicinal usage.

关键词： Afzelia africana Diabetes mellitus Haematology Antidiabetic property Aqueous extract Beneficial effect Haematological parameter Ethnomedicinal usage Wistar rat

Stiffness Analysis of Spherical Parallel Mechanism U_(P+R) with 2-DOF

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Journal of Harbin Institute of Technology(New Series) 2013年第4期20卷 41-47页

作者： Yu-Lin Zhou Long Yang Bo Li da.Xing Zeng Feng Gao School of Mechanical Engineering Yanshan University XCMG Xuzhou Truck-Mounted Crane Co. Ltd. State Key Laboratory of Mechanical System and Vibration Shanghai Jiaotong University

As one of the typical less-mobility parallel mechanisms, the spherical parallel mechanism Up.s with two degrees of freedom （2-DOF） possess high order overconstraints, and the calculation of its stiffness is partly different with general parallel mechanisms owing to the bars in each branch are assumed to be arc-shaped. By means of small deformation superposition principle, the relationship between the angle displacement and line displacement of moving platform and the forces acted on the branches were derived out. Based on the results of static analysis, the relationship between the applied force, the line displacement and the angle displacement of the mechanism was set up. And then the stiffness matrix was obtained. The six principal stiffness of the mechanism and the corresponding directions were achieved by the orthogonal transformation. The numerical calculation was performed and the results showed that the principal stiffness and directions are varied with the pose-position of the mechanism, and the principal stiffness is gradually enlarged when it is far away from the anigin. In addition, the torsion stiffness is much greater and the line deformation stiffness is smaller, the difference between the two parts is huge. The research content of this paper supplies the theoretical founda.ion for the further engineering design and application of the spherical parallel mechanism.

关键词： spherical parallel mechanism static stiffness orthogonal transformation line displacement angle

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达比加群酯-d_(3)的合成

化学试剂 2024年第1期46卷 105-110页

作者：王昌梁林辉姚永秀梁大伟董金华沈阳药科大学基于靶点的药物设计与研究教育部重点实验室辽宁沈阳110016 雅安职业技术学院药学与检验学院四川雅安625100

研究抗凝血药物达比加群酯-d_(3)的合成工艺。以4-氯-3-硝基苯甲酸甲酯为起始原料,氘代甲胺盐酸盐为氘代试剂,经氘代甲基化、取代、还原、缩合、环合、水解、亲核等反应得到关键氘化中间体3-{[(2-{[(4-氰基苯基)氨基]甲基}-1-(甲基-d_(... 详细信息

研究抗凝血药物达比加群酯-d_(3)的合成工艺。以4-氯-3-硝基苯甲酸甲酯为起始原料,氘代甲胺盐酸盐为氘代试剂,经氘代甲基化、取代、还原、缩合、环合、水解、亲核等反应得到关键氘化中间体3-{[(2-{[(4-氰基苯基)氨基]甲基}-1-(甲基-d_(3))苯并咪唑-5-基)氧亚基](吡啶-2-基)氨基}丙酸乙酯,而后再经氨解和亲核反应,成功制备稳定的达比加群酯-d_(3),8步反应总产率为6.4%,目标化合物结构经NMR和MS确认,同位素丰度达99.7%。该合成方法原料简单易得、操作简便、重现性好,可用于达比加群酯-d_(3)的合成。

关键词：抗凝血药物达比加群酯-d_(3) 合成工艺优化同位素标记

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定向凝固镁合金组织形貌及力学性能研究进展

铸造 2024年第4期73卷 453-462页

作者：靳康帅张航张旭曌连永强郭耀威房大然林小娉东北大学材料科学与工程学院辽宁沈阳110819 东北大学秦皇岛分校资源与材料学院河北秦皇岛066004

利用定向凝固技术调控镁合金晶体取向和组织结构,可以提高镁合金的力学性能。目前对镁合金定向凝固的研究仍处于探索阶段。综述了定向凝固镁合金的组织形貌及胞-枝晶转变特点,并结合课题组的研究讨论了定向凝固镁合金一次晶轴生长取向... 详细信息

利用定向凝固技术调控镁合金晶体取向和组织结构,可以提高镁合金的力学性能。目前对镁合金定向凝固的研究仍处于探索阶段。综述了定向凝固镁合金的组织形貌及胞-枝晶转变特点,并结合课题组的研究讨论了定向凝固镁合金一次晶轴生长取向及其与力学性能相关性。简要介绍了定向凝固镁合金中的长周期堆垛结构相、定向凝固镁合金的耐腐蚀性能以及定向凝固过程数值模拟的研究情况,提出了镁合金定向凝固研究的重点与方向。

关键词：定向凝固镁合金晶体取向力学性能