检索结果-南通市图书馆

Science China chemistry 2010年第5期53卷 974-979页

作者： LIU SiJin ,ZHANG ShuPing,QU Chen,LIU Wei & DU YuGuo State Key Laboratory of Environmental chemistry and Ecotoxicology Research center for Eco-Environmental sciences,Chinese Academy of sciences,Beijing 100085,China State Key Laboratory of Environmental chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing China

Polychlorinated biphenyls(PCBs) are chlorinated biphenyl compounds with wide applications in the *** spite of a ban on their production in the late 1970s,PCBs,as a group of POPs,are still persistent and widely spread in the environment,posing potential threats to human *** role of PCBs as etiologic agents for breast cancer has been intensively explored in a variety of in vivo,animal and epidemiologic *** investigations indicated higher levels of PCBs in mammary tissues or sera corresponded to the occurrence of breast cancer,but later studies showed no positive association between PCB exposure and breast cancer *** recent data suggested that the CYP1A1 m2 polymorphisms might add increased risk to the etiology of breast cancer in women with environmental exposure to *** are implicated in advancing breast cancer progression,and our unpublished data reveals that PCBs activate the ROCK signaling to enhance breast cancer ***,the correlation between PCB exposure and breast cancer risk warrants further careful investigations.

关键词： Polychlorinated biphenyls (PCBs) environmental exposure CYP1A1 polymorphisms breast cancer risk tumor progression

Fluorescence response of hypocrellin B to the environmental changes in a mimic biological membrane——liposome

在线全文

学校读者我要写书评

暂无评论

Science China chemistry 2004年第4期47卷 335-339页

作者： JIN Xuanye1,2, ZHAO Yuewei1, XIE Jie1 & ZHAO Jingquan1 1. CAS Key Laboratory of Photochemistry, center for molecular Science, institute of chemistry, Chinese Academy of Science, Beijing 100080, China 2. School of Earth sciences and Resources, China University of Geosciences, Beijing 100083, China CAS Key Laboratory of Photochemistry Center for Molecular Science Institute of Chemistry Chinese Academy of Science Beijing China School of Earth sciences and Resources China University of Geosciences Beijing China

Liposome is well known as not only a drug-delivery system but also a simple model for biological membranes. It was reported that fluorescence properties of hypocrellins were changeable over some extreme pH values. In the current work, the effects of the microenvironments on the fluorescence properties of HB in liposome, including approximately physiological range of pH values pH = 6.0-8.0, concentration of cholesterols and ionic strength of the solution, were studied. It was found that the fluorescence intensity of HB was sensitive to and also regulated by the microenvironments. When concentration of cholesterols and ionic strength keep invariable in PBS solution, there exists the maximum for the fluorescence of HB-liposome at pH 7.4 while the minimum for that of HB at pH 7.0. In addition, when pH value keeps constant (7.2), there exists the maximum at the ionic strength of 0.12 mol/kg while that at the concentration of 6×10?4 mol/L for cholesterols. On the other hand, in PBS solution, the lower the ionic strength is, the higher the fluorescence intensity is. The environment-sensitive fluorescence may be potentially applicable to probe some specific environmental features in cells or tissues.

关键词： microenvironment hypocrellin B liposome fluorescence

Ohmefentanyl stereoisomers induce changes of CREB phosphorylation in hippocampus of mice in conditioned place preference paradigm

在线全文

学校读者我要写书评

暂无评论

Cell Research 2003年第1期13卷 29-34页

作者： CAN GAO, Li WEI CHEN, JIE CHEN, XUE JUN XU, ZHI QIANG CHISecond Department of Pharmacology, Shanghai institute of Materia Medica, Shanghai institutes for Biological sciences, Chinese Academy of sciences, Shanghai 200031, ChinaResearch center for Biochemistry and molecular Biology, Xuzhou Medical College, Xuzhou, Jiangsu 221002, China Second Department of Pharmacology Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China Research center for Biochemistry and molecular Biology Xuzhou Medical College Xuzhou China

The present study was designed to determine the changes of phosphorylation of cAMP- response element binding protein (CREB) in hippocampus induced by ohmefentanyl stereoisomers (F9202 and F9204) in conditioned place preference (CPP) paradigm. The results showed that mice receiving F9202 and F9204 displayed obvious CPP. They could all significantly stimulate CREB phosphorylation and maintained for a long time without affecting total CREB protein levels. The effect of F9204 was similar to morphine which effect was more potent and longer than F9202. We also examined the effects of ketamine, a noncompetitive N-mthyl-D-aspartate receptor (NR) antagonist, on morphine-, F9202- and F9204- induced CPP and phosphorylation of CREB in hippocampus. Ketamine could suppress not only the place preference but also the phosphorylation of CREB produced by morphine, F9202 and F9204. These findings suggest that alterations in the phosphorylation of CREB be relevant to opiates signaling and the development of opiates depende

关键词： cAMP-response element binding protein (CREB) ohmefentanyl stereo isomers opiates hippocampus conditioned place preference (CPP).

Research of the Gas-solid Flow Character Based on the DEM Method

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Thermal Science 2011年第6期20卷 521-526页

作者： Xueyao Wang and Yunhan Xiao Research center for Clean Energy and Power,Chinese Academy of sciences Key Laboratory of Advanced Energy and Power,Chinese Academy of sciences (institute of Engineering Thermophysics),Beijing,100190,China Research center for Clean Energy and Power Chinese Academy of Sciences Beijing China Key Laboratory of Advanced Energy and Power Chinese Academy of Sciences (Institute of Engineering Thermophysics) Beijing China

Numerical simulation of gas-solid flow behaviors in a rectangular fluidized bed is carried out three dimensionally by the discrete element method (DEM).Euler method and Lagrange method are employed to deal with the gas phase and solid phase *** collided force among particles,striking force between particle and wall,drag force,gravity,Magnus lift force and Saffman lift force are considered when establishing the mathematic ***-sphere model is used to describe the collision of *** addition,the Euler method is also used for modeling the solid phase to compare with the results of *** flow patterns,particle mean velocities,particles' diffusion and pressure drop of the bed under typical operating conditions are *** results show that the DEM method can describe the detailed information among particles,while the Euler-Euler method cannot capture the micro-scale *** matter which method is used,the diffusion of particles increases with the increase of gas *** the gathering and crushing of particles cannot be simulated,so the energy loss of particles' collision cannot be calculated and the diffusion by using the Euler-Euler method is *** addition,it is shown by DEM method,with strengthening of the carrying capacity,more and more particles can be schlepped upward and the dense suspension upflow pattern can be ***,the results given by the Euler-Euler method are not consistent with the real situation.

关键词： DEM gas-solid flow numerical simulation

Toxicokinetics and the related metabolites in rainbow trout(Oncorhynchus mykiss) after exposure to decabromodiphenyl ether

在线全文

学校读者我要写书评

暂无评论

Science China chemistry 2010年第11期53卷 2379-2386页

作者： FENG ChengLian,XU YiPing,ZHA JinMiao,LUO Qian,SHAN XiaoQuan & WANG ZiJian State Key Laboratory of Environmental Aquatic chemistry Research center for Eco-Environmental sciences,Chinese Academy of sciences,Beijing 100085,China State Key Laboratory of Environmental Aquatic chemistry Research center for Eco-Environmental sciences Chinese Academy of Sciences Beijing China

Decabromodiphenyl ether(BDE209) is poorly absorbed by mammals,and little information is available on the toxicokinetics of BDE209 and its metabolites in *** the present study,rainbow trout(Oncorhynchus mykiss) were administered to 100 ng/g and 500 ng/g body wet weight of BDE209 via a single intraperitoneal injection and parent BDE209 and its metabolites were sequentially monitored for 28 *** results showed that toxicokinetic profiles of BDE209 could be described by the one-compartment *** the higher dose group(500 ng/g wet weight),the calculated half-life(t1/2) and elimination rate(ke) were 17.7 d and 0.039/d in the liver,and 100.3 d and 0.007/d in the muscle,*** major methoxylated brominated diphenyl ethers(MeO-BDEs) were detected with 2,2',4,4'-tetrabromo-5-methoxydiphenyl ether(5-MeO-BDE47) being detected in all tissue *** was no significant temporal change of 5-MeO-BDE47 concentration in the muscle,whereas an exponential increase was observed in the ***,the metabolism rate of BDE209 depended on the administered ***209 was hardly accumulated in the muscle of rainbow trout,while the liver was a primary metabolic ***-BDEs were formed via metabolism of BDE209,which probably played a significant role in fish toxicology as a potential indicator.

关键词： decabromodiphenyl ether(BDE209) polybrominated diphenyl ethers(PBDEs) methoxylated brominated diphenyl ethers(MeO-BDEs) toxicokinetics rainbow trout

Chemo-enzymatic Synthesis of Bioactive Compounds

在线全文

学校读者我要写书评

暂无评论

Chemo-enzymatic Synthesis of Bioactive Compounds

A　NEW　REACTION　FOR　ONE-POT,　SELECTIVE　MONO-O-GLYCOSYLATIONS　OF　9,10-DIHYDROXYPHENANTHRENE　UNDER　MILD　CONDITIONS

中国化学会第二十五届学术年会

作者： Mei-Xiang Wang Laboratory of molecular Recognition and Selective Synthesis, institute of chemistry & center for molecular Science, Chinese Academy of sciences, 100080, Beijing

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1996年第5期7卷 423-424页

作者： ZHong Wu GUO Youg ZHeng HUI(Shanghai institute of Organic chemistry, Chinese Academy of sciences 364 Fenglin Lu, Shanghai 200032) Shanghai Inst. of Organic chemistry Chinese Academy of Sciences 354 Fenglin Lu Shanghai 200032

Abstract: 9, 10-Dihydroxyphenanthrene was Selectively mono-O-glycosylated by a new, one-pot reaction through its elevated phospholane inermediate. The reactions were canrried out under mild conditions without aedvatio... 详细信息

关键词： MILD UNDER DIHYDROXYPHENANTHRENE CONDITIONS

Removal Behaviors of Different SiC Ceramics during Polishing

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2010年第2期26卷 125-130页

作者： Guiling Liu, Zhengren Huang , Xuejian Liu and Dongliang Jiang Structural Ceramics center, Shanghai institute of Ceramics, Chinese Academy of sciences, Shanghai 200050, China Structural Ceramics center Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

Comparative experiments were conducted to reveal the removal behaviors of three kinds of silicon carbide （SIC） ceramics during polishing and the effects of ceramic microstructure on the surface quality were also reported. Experimental results show that the second phase in SiC ceramics plays an important role in the surface quality when its size is large enough. The surface quality is enslaved to the formation of steps at interfaces between second phase and SiC matrix that results from different elastic modulus and hardness between two phases. Under 3 μm abrasive grains polishing condition, different SiC ceramics show different removal mechanisms. With decreasing abrasive grain size, all of different SiC ceramics exhibit a ductile removal mode, which decreases surface roughness efficiently.

关键词： SiC Surface quality Removal behavior Polishing

Study on the Bond Covalency and Bond Susceptibility in NdCr_(1-x)M_xO_3 (M=Mn, Fe, Co)

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1998年第12期9卷 0-0页

作者： Zhi Jian WU Qing Bo MENG Si Yuan ZHANG (Changchun institute of Applied chemistry Chinese Academy of sciences, Changchun 130022) Changchun Inst. of Applied chemistry Chinese Academy of Sciences Changchun 130022 China

Relationship between the conformation and enzyme activity of the commercial and purified GOD have been studied. Both enzyme activity and value of (α/β of purified GOD in water solution and LB film were higher than t... 详细信息

关键词： GOD conformation enzyme activity

On the Generalized Theory of Atmospheric Particle Systems

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric sciences 1995年第4期12卷 419-438页

作者： Liu Yangang (Desert Research institute, Atmospheric sciences center, Reno, Nevada 89506-0220,USA) Atmospheric sciences center Desert Research Institute Reno USA

Unification is both necessary and challenging for studying atmospheric particle systems, which are polydispersesystems containing particles of different sizes and shapes. A general framework is proposed to realize the first order generalization. Within this generalized framework, (1) atmospheric particle shapes are unified into self-similar fractals; (2) a self-similar particle is characterized by various power-law relationships; (3) by combining these power-law relationships for a single particle with Shannon's maximum entropy principle and some concepts in statistical mechanics, unified maximum likelihoood number size distributions are of the Weibull form for atmospheric particle systems. Frontier disciplines (e. g., scaling,fractal,chaos and hierarchy) are argued to provide potential 'tools' for such unification. Several new topics are raised for future research.

关键词： Unification Self-similarity,Power-law relationships,Fractals Shannon's entropy Maximum likelihood distribution