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Salvicine,a novel topoisomerase Ⅱ inhibitor,exerts its potent anticancer activity by ROS generation

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Acta Pharmacologica Sinica 2007年第9期28卷 1460-1465页

作者： Ling-hua MENG Jian DING Division of Antitumor Pharmacology,State Key laboratory of Drug Research,Shanghai institute of Materia Medica,chinese academy of sciences,Shanghai 201203,china Division of Antitumor Pharmacology State Key laboratory of DrugResearchShanghai Institute of Materia MedicaChinese Academy oj SciencesShanghai 201203China

Salvicine is a novel diterpenoid quinone compound obtained by structural modi-fication of a natural product lead isolated from a chinese herb with potent growthinhibitory activity against a wide spectrum of human tumor cells in vitro and inmice bearing human tumor xenografts. Salvicine has also been found to have aprofound cytotoxic effect on multidrug-resisitant (MDR) cells. Moreover, Salvicinesignificantly reduced the lung metastatic foci of MDA-MB-435 orthotopicxenograft. Recent studies demonstrated that salvicine is a novel non-intercalativetopoisomerase II (Topo II) poison by binding to the ATPase domain, promotingDNA-Topo II binding and inhibiting Topo II-mediated DNA relegation and ATPhydrolysis. Further studies have indicated that salcivine-elicited ROS plays acentral role in salvicine-induced cellular response including Topo II inhibition,DNA damage, circumventing MDR and tumor cell adhesion inhibition.

关键词： Salvicine is a novel diterpenoid quinone compound obtained by structural modi-fication of a natural product lead isolated from a chinese herb with potent growthinhibitory activity against a wide spectrum of human tumor cells in vitro and inmice

MINERALIZATION AGES OF GOLD-HYDROTHERMAL DEPOSITS IN NORTHERN ZONE OF EASTERN KUNLUN MOUNTAINS BASED ON FISSION TRACK ANALYSIS

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地学前缘 2000年第S1期7卷 329-330页

作者： Yuan Wanming 1,Wang Shicheng 1,Mo Xuanxue 2,Wang Lanfen 1[WT5,5”BX](1 institute of High Energy Physics, chinese academy of sciences, Beijing 100080,china 2 china University of Geosciences, Beijing 100083,china)

The age of mineralization in a mining area is a primary factor in various researches related to ore\|forming process. It is that the uncertainty of mineralization ages of gold ore deposits in northern zone of eastern Kunlun Mountains, Qinghai Province, restrains to probe the relationship of the deposits to the regional tectonic evolution. This paper documents the fission track method used to determine the ages of gold ore deposits in eastern Kunlun Mountains and considers the implication for the origin of the *** Kunlun Mountains is the northern part of the Qinghai—Tibet Plateau and is of three deep\|seated fault belts in about EW extension. This work mainly includes three gold ore districts. All of them, in the north of Mid\|Kunlun fault belt, belong to northern part of eastern Kunlun Mountains. The Yanjingou district, with geographical coordinate 96°00’E and 36°10’N, is located 60 km north of Hongqigou district . Both of them are large, typical tectonoalteration gold deposits and were formed in similar geological setting. Hongshuihe ore district is located 50 km east of Yanjingou district and includes tectonoalteration and magmatic cryptoexplosive gold deposits. Outcroped strata are dominantly Jinshuikou Group metamorphic rocks of Lower Proterozoic erathem. The occurrence area of igneous rocks, especially granitoid, accounts for about 90% in first two districts and become less in Hongshuihe district. The gold deposits occur in NW\|striking fault belts. The Rb\|Sr isochron age and K\|Ar isotopic age of Moyite relevant to the gold mineralization are respectively 228 25Ma and 207 1Ma. Rb\|Sr dating of diorite porphyrite is 209 09Ma. Sericite selected from Yanjingou orebody has 252 9Ma K\|Ar age. The ore in Hongqigou district has 197Ma K\|Ar age and 210Ma model age of Pb isotope of galena.

关键词： mineralization age thermal event fission track thermochron ology fission track analysis eastern Kunlun Mountains

Multisymplectic five-point scheme for the nonlinear wave equation

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chinese Science Bulletin 2003年第S2期48卷 24-29页

作者： WANG Yushun~(1,2), WANG Bin~1, YANG Hongwei~1 & WANG Yunfeng~1 1. LASG, institute of Atmospheric Physics, chinese academy of sciences, Beijing 100029. china 2. Permanent address: School of Mathematics and Computer Science, Nanjing Normal University, Nanjing 210097. china chinese Acad Sci Inst Atmospher Phys LASG Beijing 100029 Peoples R China Nanjing Normal Univ Sch Math & Comp Sci Nanjing 210097 Peoples R China

In this paper, we introduce the multisymplecticstructure of the nonlinear wave equation, and prove that theclassical five-point scheme for the equation is multisymplec-tic. Numerical simulations of this multisymplectic scheme onhighly oscillatory waves of the nonlinear Klein-Gordonequation and the collisions between kink and anti-kink soli-tons of the sine-Gordon equation are also provided. The mul-tisymplectic schemes do not need to discrete PDEs in thespace first as the symplectic schemes do and preserve notonly the geometric structure of the PDEs accurately, but alsotheir first integrals approximately such as the energy, themomentum and so on. Thus the multisymplectic schemeshave better numerical stability and long-time numerical be-havior than the energy-conserving scheme and the symplec-tic scheme.

关键词： symplectic schelne energy-conserving scheme multisymplectic scheme nonlinear wave equation.

Second Harmonic Conversion-efficiency of Aberrated Laser Beam

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chinese Journal of Lasers 2001年第6期10卷 61-65页

作者： HOU Jin 1,2 ZHANG Yudong 1 JIANG Wenhan 1 1) institute of Optics and Electronics, The chinese academy of sciences, Chengdu 610209, china 2) institute of Science, National University of Defense Technology, Changshe 410073,china 中科院光电技术所四川成都 610209

How aberrations of pump wave affect second harmonic generation is studied. The solution is applied to type I second harmonic generation in KDP crystal. The results of conversion-efficiency and transverse intensity distribution in second harmonic generation of Gaussian beam and super-Gaussian beam with aberrations of Zernike polynomials are presented.

关键词： second harmonic aberration conversion-efficiency Gaussian beam super-Gaussian beam

Studies on steroidal plant growth regulator——*** construction of the side chain of brassinosteroid by employing a separated dialkylation and a tandem dialkylation of the pyranone moiety

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chinese Journal of Chemistry 1993年第4期11卷 376-384页

作者： ZHOU,Wei-Shan Shanghai institute of Organic Chemistry,chinese academy of sciences,Shanghai 200032SUN,Li-Qiang PAN,Xin-Fu Department of Chemistry Lanzhou University,Laahou 730000 1Shanghai institute of Organic Chemistry Chinese Academy of Sciences Shanghai 2000322Department of Chemistry 'Lanzhou University Laahou 730000

A stereocontrolled construction of the side chain of brassinosteroid was developed via the separated dialkylation and the tandem dialkylation of the pyranone moiety as the key step.

关键词： Studies on steroidal plant growth regulator Stereoselective construction of the side chain of brassinosteroid by employing a separated dialkylation and a tandem dialkylation of the pyranone moiety

Heat transfer process of roadway embankments with different type and width of road surface in permafrost regions

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Progress in Natural Science:Materials International 2007年第3期17卷 314-319页

作者： YU Qihao, PAN Xicai, CHENG Guodong and BAI Yang (State Key Laboratory of Frozen Soil Engineering, Cold and Arid Regions Environment and Engineering Research institute, chinese A-cademy of sciences, Lanzhou 730000, china) [a]State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environment and Engineering Research Institute Chinese Academy of Sciences Lanzhou China

The stability of roadbed in permafrost areas has become a big concern with rapid development and construction of throughways, highways and railways in these areas under the current climate change since it is governed by the thermal condition, or in other words, the heat transfer process in the embankment. We carried out a finite element analysis to analyze the effects of different types of road surface and the effect of breadth of embankment on the embankment heat transfer process. The results indicated that the mean annual heat transfer rate at the bottom of the roadway embankment with asphalt surfaces is 3 times that with sandy gravel surfaces. This means annual heat transfer rate increased by 60% when the breadth of asphalt surface was doubled. The increased heat transfer rate was mainly located at the bottom of the embankment and resulted in the effect of thermal concentration,. leading to degradation of the permafrost by as much as 1.6 times. It was also found that increasing embankment height would not reduce these increases of the heat transfer rate. Therefore both asphalt road surface and increased embankment breadth can lead to an intensified heat transfer rate in roadway embankment, consequently degradating the underlying permafrost and embankment instability.

关键词： wide road surface roadway embankment permafrost regions process of heat transfer heat flux ground temperature field.

Characterization of a Mutant Listeria monocytogenes Strain Expressing Green Fluorescent Protein

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Acta Biochimica et Biophysica Sinica 2005年第1期37卷 19-24页

作者： Ling-Li JIANG Hou-Hui SONG~1 Xue-Yan CHEN Chun-Lin KE Jing-Jing XU Ning CHEN Wei-Huan FANG~* institute of Preventive Veterinary Medicine and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine.Zhejiang University,Hangzhou 310029,china ~1 institute of Microbiology.chinese academy of sciences.Beijing,100080.china institute of Preventive Veterinary Medicine and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine Zhejiang UniversitvHang-hou 310029China "institute of Microbiology Chinese Academy of SciencesBeijing 100080China

To construct a recombinant strain of Listeria monocytogenes for the expression of heterolo-gous genes,homologous recombination was utilized for insertional mutation,targeting its listeriolysin O gene(hly).The gene encoding green fluorescent protein(GFP)was used as the indicator of heterologous *** gene gfp was inserted into hly downstream from its promoter and signal sequence by anoverlapping extension polymerase chain reaction,and was then cloned into the shuttle plasmid pKSV7 forallelic exchange with the *** *** recombination was achieved by grow-ing the electro-transformed *** cells on chloramphenicol plates at a non-permissive *** analysis indicated correct insertion of the target gene in-fi-ame with the signal *** strain expressed GFP constitutively as revealed by fluorescence *** mutant *** hly-gfp lost its hemolytic activity as visualized on the blood agar or when analyzed with theculture supernatant *** insertional mutation resulted in a reduced virulence of about 2 logs lessthan its parent strain *** 10403s as shown by the 50%-lethal-dose assays in the mouse andembryonated chicken egg *** results thus demonstrate that mutated *** could be apotential carrier for the expression of heterologous passenger genes or could act as an indicator organism inthe food industry.

关键词： Listeria monocytogenes homologous recombination insertional mutation heterologous gene expression green fluorescent protein(GFP)

The Dissociation of Polyatomic Molecules in Intense Laser Field

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The Dissociation of Polyatomic Molecules in Intense Laser Fi...

INVESTIGATION　OF　ACTIVE　CONTROL　FOR　DYNAMIC　STABILITY　OF　HELICOPTER　ROTOR－BODY　COUPLING

CCAST“2002年全国强场激光物理”研讨会

作者： Fanao Kong institute of Chemistry chinese academy of sciences

＜正＞研究意义108V/cm ∽1013W/cm2Laser Intensity: I=E/（A*△t）I:激光强度,E:激光能量A:光斑面积,△t:脉冲宽度

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chinese Journal of Aeronautics 1996年第4期9卷 269-272页

作者： Ling Aimin(chinese Helicopter Research and Design institute,Jindezhn, Jiangxi, china, 333001) chinese Helicopter Res. Des. Inst. Jindezhen Jiangxi 333001 China

A study is conducted on the feasibility of helicopter ground and air resonanceby using actively controlled tabs mounted at the trailing edge of an aerofoil. A method isdeveloped to obtain the optimal feedback control law through constructing a referencemodel according to requirements of stability levels in the modal space. The effects of rotorspeed and length and location of tabs on the control law are analyzed, and it is found possible that a controller can be designed into constant feedback gain against rotor speed andto feed back only to the dominant system states to eliminate the unstable range of rotorspeed.

关键词： tabs (control surfaces) helicopters rotor body interactions coupling dynamic stability active control