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Reversal of multidrug resistance in vincristine-resistant human gastric cancer cell line SGC7901/VCR by LY980503

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World Journal of Gastroenterology 2007年第15期13卷 2234-2237页

作者： da-Long Wu ying Xu li-Xin yin Huan-Zhang Lu Department of Pharmacology School of Medicine Jiaxing Colloge Jiaxing 314001 Zhejiang Province China Department of Histology and Embryology School of Medicine Jiaxing College Jiaxing 314001 Zhejiang Province China Department of Chemical Synthesis Institute of Microbiology and Epidemiology Academy of Military Medical Sciences Beijing 100071 China Department of Clinical Pharmacology Affiliated Hospital Academy of Military Medical Sciences Beijing 100039 China

AIM： To investigate the reversal effect of LY980503, a benflumetol derivative, on multidrug resistance in vincristine （VCR） -resistant human gastric carcinoma cell line SGC7901/VCR. METHODS： Cells of a human gastric cancer cell line, SGC7901, and its VCR-resistant variant, SGC7901/VCR, were cultivated with LY980503 and/or doxorubicin （DOX）. The cytotoxicity of drugs in vitro was assayed by M-IF method. Based on the flow cytometric technology, the uptake of DOX was detected in these cells by measuring DOX -associated mean fluorescence intensity （MFI）. RESULTS： SGC7901/VCR cells were 23.5 times more resistant to DOX in comparison with 5GC7901 cells. LY980503 at the concentrations of 2.0 μmol/L -10 μmol/ L had no obvious cytotoxicity to SGC7901 and SGC7901/ VCR cells. After simultaneous treatment with LY980503 at the concentrations of 2.0, 4.0 and 10 μmol/L, the ICso of DOX to SGC7901/VCR cells decreased from 1.6 ± 0.12 μmol/L to 0.55 ± 0.024, 0.25 ± 0.032 and 0.11 ± 0.015 μmol/L, respectively, thus, increasing the DOX sensitivity by 2.9-fold （P 〈 0. 05）, 6.4-fold （P 〈 0. 01） and 14.5-fold （P 〈 0. 01）, respectively. In the uptake study of DOX, simultaneous incubation of SGC7901/VCR cells with LY980503 significantly increased the DOX -associated MFI in SGC7901/VCR cells. No such results were found in parental SGC7901 cells.CONCLUSION： LY980503 at non-cytotoxic concentrations can effectively circumvent resistance of SGC7901/VCR cells to DOX by increasing intracellular DOX accumulation.

关键词： Hultidrug resistance Benflumetol Doxorubicin Gastric cancer Reversal

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注塑机电动托模伺服控制系统研究

自动化技术与应用 2015年第1期34卷 6-9页

作者：谢子方李大寅王文婷张奇之朱立琼陈列宁波安信数控技术有限公司浙江宁波315801 海天塑机集团浙江宁波315801

介绍一种注塑机电动托模的伺服控制技术,通过伺服运动控制卡、伺服驱动器、伺服电机和滚珠丝杠实现注塑机托模机构的伺服闭环运动控制。整个运动控制过程采用S曲线加减速运动控制算法,能够有效减少运动过程中的冲击,提高滚珠丝杠和托模... 详细信息

介绍一种注塑机电动托模的伺服控制技术,通过伺服运动控制卡、伺服驱动器、伺服电机和滚珠丝杠实现注塑机托模机构的伺服闭环运动控制。整个运动控制过程采用S曲线加减速运动控制算法,能够有效减少运动过程中的冲击,提高滚珠丝杠和托模机构的寿命。

关键词： S曲线加减速伺服控制电动托模注塑机

Characteristics of outdoor pollutants intrusion and ventilation control in sentry buildings with normal openings

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Building Simulation 2023年第3期16卷 393-411页

作者： linfeng liang Haiguo yin da Zhang Yuekun Han Yanyan li Jingying Zhang Yongshou Zhang Zhenjun Ma Angui li School of Building Services Science and Engineering Xi'an University of Architecture and TechnologyXi'an 710055ShaanxiChina Qinghai Building and Materials Research Co. LtdXining 810008QinghaiChina Qinghai Provincial Key Laboratory of Plateau Green Building and Eco-community Xining 810008QinghaiChina Sustainable Buildings Research Centre University of WollongongWollongongNSW 2522Australia

Sentry buildings have windows that are often open to facilitate communication between *** also provides the possibility for the intrusion of pollutants such as vehicle exhaust *** prevent the intrusion of outdoor pollutants and create an excellent indoor environment,internal circulation with double-attached ventilation(IC-daV)and external circulation with double-attached ventilation(EC-daV)are proposed for such buildings,and the isolation effect of two attached ventilation modes on pollutants is compared with that of natural ventilation.A computational fluid dynamics(CFD)method was used to simulate the transportation process and indoor distribution of outdoor pollutants intruding into sentry buildings from the regular openings under different outdoor wind directions,wind velocities,and states of the doors and ventilation *** results indicate that the leeward airflow of the three wind directions caused the largest pollutants to invade the *** amount of pollutants intrusion increased with increasing wind *** the leeward airflow and the windward airflow blow through the building,opening the door increased the amount of pollutants intruding into the room by 3.34 times and 8.85 times,respectively,compared with closing the ***,the IC-daV can isolate 81.7% of the pollutants while the EC-daV can isolate 99.92% of the pollutants as compared with natural *** double attached ventilation mode in buildings can effectively prevent the intrusion of outdoor pollutants into the room,reduce the harm of outdoor pollutants to the health of indoor personnel,and provide a new idea for buildings to improve the indoor air quality.

关键词： sentry buildings pollutants intrusion indoor air quality wind field double attached ventilation computational fluid dynamics(CFD)

Sensitive and Rapid Quantification of Felodipine by High-performance liquid Chromatography-tandem Mass Spectrometry(HPLC-MS/MS) and Its Pharmacokinetics in Healthy Chinese Volunteers

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Chemical Research in Chinese Universities 2006年第4期22卷 479-483页

作者： li Yan-yan yin Yi-zi SUN Zhi-hui li Xin HU li-gang li Peng-fei ZHONG da-fang The First Hospital Jilin University Changchun 130021 P.R. China Research Center for Drug Metabolism Jilin University Changchun 130021 P. R. China

To investigate the pharmacokinetics of felodipine in the plasma of healthy Chinese volunteers, 30 healthy volunteers received a single oral dose of 5 mg of extended release felodipine tablets. The felodipine was extracted from the matrix with a liquid-liquid extract procedure and analyzed by high-performance liquid chromatography-tandem mass spectrometry in the multiple reaction monitoring（MRM） mode using an electrospray ion source with positive ion detection. The method was validated over a felodipine concentration range of 0. 05-10.00 ng/mL in human plasma. Its main pharmacokinetic parameters values were： ρmax = （ 1.67 ± 0. 84 ） ng/mL, occurring at （ 3.93 3± 2. 49 ） h; the plasma elimination half-life：（23. 08 3± 9. 48） h and the area under the plasma concentration versus time curve：（29. 94 ± 14. 39） ng · h/mL. The validation results demonstrated that this method showed a satisfactory precision and accuracy across the calibration range. The procedure involved minimal drug administration, sample preparation, and a 2. 5-min chromatographic run time. It was well suited to clinical studies of the drug involving large numbers of samples.

关键词： Felodipine liquid chromatography-tandem massspectrometry Pharmacokinetics

Secondary plasmon resonance in graphene nanostructures

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Frontiers of physics 2015年第1期10卷 103-109页

作者： Yang li Hong Zhang da-Wei Yan Hai-Feng yin Xin-Lu Cheng College of Physical Science and Technology Sichuan University Chengdu 610065 China Key Laboratory of High Energy Density Physics and Technology of Ministry of Education Sichuan University Chengdu 610065 China Research Center of Laser Fusion China Academy of Engineering Physics Mianyang 621900 China College of Science Kaili University Kaili 556011 China

The plasmon characteristics of two graphene nanostructures are studied using time-dependent den- sity functional theory （TDDFT）. The absorption spectrum has two main bands, which result from and σ ＋ π plasmon resonances. At low energies, the Fourier transform of the induced charge density maps exhibits anomalous behavior, with a π phase change in the charge density maps in the plane of the graphene and those in the plane 0.3 A from the graphene. The charge density fluctuations close to the plane of the graphene are much smaller than those above and beneath the graphene plane. However, this phenomenon disappears at higher energies. By analyzing the electronic properties, we may conclude that the restoring force for the plasmon in the plane of the graphene does not result from fixed positive ions, but rather the Coulomb interactions with the plasmonic oscillations away from the plane of the graphene, which extend in the surface-normal direction. The collective oscillation in the graphene plane results in a forced vibration. Accordingly, the low-energy plasmon in the graphene can be split into two components： a normal component, which corresponds to direct feedback of the external perturbation, and a secondary component, which corresponds to feedback of the Coulombic interaction with the normal component.

关键词： time-dependent density functional theory (TDDFT) graphene nanostructure plasmon,induced charge

A New Method of Deoxygenation in the Synthesis of Taxanes by Hypophosphorous Acid

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有机化学 2003年第Z1期23卷 340-341页

作者： GU Jun ZHANG Meng yin da-li Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100050 Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100050 Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100050

　　Based on the chemistry involved in the radical chain deoxygenation of alcohols by the Barton-McCombie reaction, numerous applications in the synthesis of taxanes were reported. [1] In the original Barton-McCombie method,tributyltin hydride was the hydrogen atom source and tributyltin radical generated from the hydride served as a chain carrier. [2] Although the method gave the good yield and found many applications, the problems associated with the price, toxicity and removal of tin residues prompted search for other hydrogen atom sources. Radical chain deoxygenation of alcohols can be carried out with phosphorus centered radicals, generated from hypophosphorous acid orits salts. [3]……

关键词： Hypophosphorous Acid hydrogen atom hypophosphorous acid

Energy Efficient Predictive Control for Vapor Compression Refrigeration Cycle Systems

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IEEE/CAA Journal of Automatica Sinica 2018年第5期5卷 953-960页

作者： Xiaohong yin Shaoyuan li the School of Automation and Electronic Engineering Qingdao University of Science and TechnologyQingdao 266042China the Department of Automation Shanghai Jiao Tong Universityand the Key Laboratory of System Control and Information ProcessingMinistry of Education of ChinaShanghai 200240China

Abstract--Vapor compression refrigeration cycle （VCC） system is a high dimensional coupling thermodynamic system for which the controller design is a great challenge. In this paper, a model predictive control based energy efficient control strategy which aims at maximizing the system efficiency is proposed. Firstly, according to the mass and energy conservation law, an analysis on the nonlinear relationship between superheat and cooling load is carried out, which can produce the maximal effect on the system performance. Then a model predictive control （MPC） based controller is developed for tracking the calculated setting curve of superheat degree and pressure difference based on model identified from data which can be obtained from an experimental rig. The proposed control strategy maximizes the coefficient of performance （COP） which depends on operating conditions, in the meantime, it meets the changing demands of cooling capacity. The effectiveness of the control performance is validated on the experimental rig. Index Terms--Cooling load, model predictive control （MPC）, superheat, vapor compression refrigeration cycle （VCC）.

关键词： Cooling load model predictive control(MPC) superheat vapor compression refrigeration cycle(VCC)

VIBRATION ANALYSIS OF MICROSCALE PLATES BASED ON MODIFIED COUPLE STRESS THEORY

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Acta Mechanica Solida Sinica 2010年第5期23卷 386-393页

作者： li yin Department of Mechanics Huazhong University of Science and Technology Wuhan 430074 China Hubei Key Laboratory for Engineering Structural Analysis and Safety Assessment Wuhan 430074 China

A non-classical Kirchhoff plate model is developed for the dynamic analysis of microscale plates based on the modified couple stress theory in which an internal material length scale parameter is included. Unlike the classical Kirchhoff plate model, the newly developed model can capture the size effect of microscale plates. Two boundary value problems of rectangular micro- plates are solved and the size effect on the lowest two natural frequencies is investigated. It is shown that the natural frequencies of the microscale plates predicted by the current model are size-dependent when the plate thickness is comparable to the material length scale parameter.

关键词： microscale plate vibration natural frequency modified couple stress theory size effect

Effects of Hypoxia on the Growth and Development of the Fetal Ovine Hepatocytes in Primary Culture

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Biomedical and Environmental Sciences 2019年第8期32卷 592-601页

作者： CAO li WANG Juan BO Le li da Wei yin Na ZHOU An Wen MAO Cai Ping Reproductive Medicine Center First Affiliated Hospital of Soochow UniversitySuzhou 215006JiangsuChina College of Pharmaceutical Sciences Soochow UniversitySuzhou 215006JiangsuChina

Objective To investigate the development and characterizations of the hepatocytes isolated from fetal ovine and to determine the effect of hypoxia on their growth and *** Fresh hepatocytes were isolated from the liver of fetal ovine at late gestation, cultured in specific media, and exposed to normoxia(21% O2) or hypoxia(2% O2).The cellular characteristics and population purity were identified by immunocytochemistry and flow cytometry(FCM).The effects of hypoxia on cell cycle and apoptosis of the hepatocytes were evaluated by FCM, whereas the cellular ultrastructure changes were examined with a transmission electron *** The cell purity of hepatocytes was over 95%.Under hypoxia exposure, the hepatocytes showed a gradual increase in proportion at the S phase and in proliferative index, followed with a compatible increase in apoptosis and progressively decreased cell ***, the organelles of the hepatocytes demonstrated dramatic changes, including swelling of mitochondria, disorder in cristae arrangement, expansion of endoplasmic reticulum, and a large number of circular lipid droplets emerging in the *** Fetal ovine hepatocytes could be primarily cultured in a short-term culture system with a high purity of over 95% and with their preserved original *** could induce changes in ultrastructural and inhibit the proliferation of cultured fetal ovine hepatocytes through apoptotic mechanisms.

关键词： Cell cycle Fetal ovine hepatocytes Hepatocytes structure Hypoxia Primary culture