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

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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

Investigation on the eigenvalue-equation problem of molecular crystals and polymers

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Chinese Journal of Chemistry 1990年第6期8卷 481-491页

作者： YAN, Ji-Min ZHANG, Qi-Yuan, institute of Chemistry, academia sinica, Beijing 100080 institute of Chemistry Academia Sinica Beijing 100080

One-dimensional periodic system, such as molecular crystal and polymer, can be expressed as ... ABABAB ... structure, where A and B stand for a complete molecule or a part of a molecule. When (AB) is taken as a structure unit, one can obtain the complex generalized eigenvalue-equation H^(AB) (k) C^(AB) (k)=S^(AB) (k)C^(AB) (k)E^(AB) (k); and if (BA)is taken as a structure unit, the corresponding eigenvalue-equation is H^(BA)(k) C^(BA)(k)=S^(BA)(k) C^(BA)(k) E^(BA)(k). The relationship between the two equations has been investigated. The results of theoretical analysis are E_m^(BA) (k)= E_m^(AB)(k); C_(j_am)^(BA)(k)=C_(j_am)^(AB). exp (i△) and C_(j_bm)^(BA)(k)=C_(j_bm)^(AB)(k). exp[i(k.R_(-1)+△)]=C_(j_bm)^(AB)(k)× exp (i△??) where j_a and j_b are the index number of atomic orbitals within (A) and (B) respectively, and m stands for the index number of crystal or polymer orbitals. This result has been verified by the concrete calculation of three periodic systems: (1) hydrogen-molecular chain, ...H (A) H (B) ... H (A) H (B) ..., (2) polyphenylene, ... (A) (B) (A) (B) ..., where (A) and (B) stand for =C (CH=): and (=HC)_2 C= respectively, and (3) the TCNQ molecular column, ... TCNQ (A). TCNQ (B) ... TCNQ (A). TCNQ(B)... . The results can be generalized to two- and three-dimensional systems straightforwardly.

关键词： BA exp AB

Investigation of 'chazi'(damaged-enamels)on Chenghua doucai Porcelains

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Science china(Technological sciences) 2009年第6期52卷 1722-1729页

作者： DU Feng1 & SU BaoRu2 1 institute of Chemistry & molecular Engineering,Qingdao University of Science & Technology,Qingdao,china 2 College of Information Science & Technology,Qingdao University of Science & Technology,Qingdao,china institute of Chemistry & molecular Engineering Qingdao University of Science & Technology Qingdao China College of Information Science & Technology Qingdao University of Science & Technology Qingdao China

At the end of the 1950s,Sun Yingzhou considered that the 'chazi'(damaged colour)on Chenghua doucai imperial porcelain as a defect was originally produced in firing process during Chenghua period(1465―1487).Researchers in china have accepted his *** any fragment with the 'chazi' has never been found in several tons of Chenghua imperial sherds excavated from Ming imperial kiln site in *** china,few scholars have questioned the formation of 'chazi',and further investigated *** researchers at the Research Laboratory in the British Museum,employing unde-structive EDXRF,have analyzed the chemical composition of the 'chazi'(damaged colour)on a Chen-ghua doucai stem cup in the museum,and they have confirmed that the 'chazi'(damaged colour)was caused by the fire of the Jianfu palace in the Forbidden City in *** on their research,the authors studied the colour chemical principle of the 'chazi's' formation *** to the ceramic technology principle,scientific reasoning for the 'chazi' was carried *** the help of the history of Qing court,the brainteaser of the 'chazi' was totally uncovered,the misunderstanding for the 'chazi' has also been *** research also suggests that employing modern science and technology is a direction to study Chinese ancient ceramic further.

关键词： Chenghua doucai porcelains court eunuchs the set on fire at the Jianfu palace ’chazi’(damaged-enamels) the British Museum colour chemical principle archaeology using science and technology

A　molecular　Dynamical　Theory　of　Ultraweak　Bio－photon　Emission　in　the　LivingSystems　and　Its　Propertes（1）

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原子与分子物理学报 1995年第4期12卷 411-419页

作者： Pang Xiaofeng(International Centre for arterial Physics, academia sinica Shenyang 110015)(and Dept. of Physics,Southwest institute for Nationalities Chengdu 610041 china) 中科院国际材料物理中心辽宁沈阳 110015

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ＡＭｏｌｅｃｕｌａｒＤｙｎａｍｉｃａｌＴｈｅｏｒｙｏｆＵｌｔｒａｗｅａｋＢｉｏ－ｐｈｏｔｏｎＥｍｉｓｓｉｏｎｉｎｔｈｅＬｉｖｉｎｇＳｙｓｔｅｍｓａｎｄＩｔｓＰｒｏｐｅｒｔｅｓ（１）￥ＰａｎｇＸｉａｏｆｅｎｇ（ＩｎｔｅｒｎａｔｉｏｎａｌＣｅｎｔｒｅｆｏ...

关键词： Bio-photon emission Supersonic soliton Temperature Non-linear vibration

A possible proton pygmy resonance in ^(17)Ne

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Science china(Physics,Mechanics & Astronomy) 2011年第S1期54卷 49-52页

作者： MA ZhongYu1,2 & TIAN Yuan1 1 china institute of atomic Energy, Beijing 102413, china 2 Center of Theoretical Nuclear Physics, National Laboratory of Heavy Collision, Lanzhou 730000, china china institute of atomic Energy Beijing China Center of Theoretical Nuclear Physics National Laboratory of Heavy Collision Lanzhou China

The low-lying electric dipole strengths in proton-rich nuclei 17F and 17Ne, which can be produced at HIRFL-CSR in Lanzhou, are investigated. In the framework of the covariant density functional theory the self-consistent relativistic Hartree Bogoliubov model and the relativistic quasiparticle random phase approximation with the NL3 parameter set and Gogny pairing interaction are adopted in the calculations. A pronounced dipole peak appears below 10 MeV in17Ne, but does not occur in 17F. The prop erties of this low-lying E1 excitation in 17Ne are studied, which may correspond to a proton pygmy resonance with different characteristics from those of giant dipole resonance.

关键词： proton pygmy resonance relativistic Hartree-Bogoliubov model relativistic quasiparticle random phase approximation

Insulin improves cardiomyocyte contractile function through enhancement of SERCA2a activity in simulated ischemia/reperfusion

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Acta Pharmacologica sinica 2006年第7期27卷 919-926页

作者： Jie YU~2 Hai-feng ZHANG~2 Feng WU~2 Qiu-xia LI~2 Heng MA~2 Wen-yi GUO~3 Hai-chang WANG~3 Feng GAO~(2,3,4,5)2 Department of Physiology3 Department of Cardiology,Xijing Hospital,Fourth Military Medical University,Xi'an 710032,china 4 institute of molecular Medicine,Peking University,Beijing 100871,china Department of Physiology Xijing Hospital Fourth Military Medical University Xi'an China Department of Cardiology Xijing Hospital Fourth Military Medical University Xi'an China institute of molecular Medicine Peking University Beijing China

Aim:Insulin exerts anti-apoptotic effects in both cardiomyocytes and coronaryendothelial cells following ischemia/reperfusion（I/R）via the Akt-endothelial ni-tric oxide synthase survival signal *** important insulin signalingmight further contribute to the improvement of cardiac function after *** this study,we tested the hypothesis that sarcoplasmic reticulum calcium-AT-Pase（SERCA2a）is involved in the insulin-induced improvement of cardiac con-tractile function following I/***:Ventricular myocytes were enzymaticallyisolated from adult SD *** I/R was induced by perfusing cells withchemical anoxic solution for 15 min followed by reperfusion with Tyrode's solu-tion with or without insulin for 30 *** shortening and intracellularcalcium transients were assessed and underlying mechanisms were ***:Reperfusion with insulin(10-7mol/L)significantly improved the recoveryof contractile function（n=15-20 myocytes from 6-8 hearts,P2+)fluorescenceratio,shortened time to peak Ca2+and time to 50% diastolic Ca2+,compared withthose in cells reperfused with vehicle（P2a activity were both increased in insulin-treated I/R cardiomyocytes,which were markedly inhibited by pretreatment of cells with a specific Akt ***,inhibition of Akt activity abolished insulin-induced positive contrac-tile and calcium transients responses in I/R ***:Thesedata demonstrated for the first time that insulin improves the recovery of contrac-tile function in simulated I/R cardiomyocytes in an Akt-dependent and SERCA2a-mediated fashion.

关键词： insulin ischemia/reperfusion cardiomyocyte contraction calcium transients SERCA2a Akt

Taurine inhibits ischemia/reperfusion-induced compartment syndrome in rabbits

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Acta Pharmacologica sinica 2005年第7期26卷 821-827页

作者： Ji-xian WANG~(2,3) Yan LI~2 Li-ke ZHANG~4 Jing ZHAO~5 Yong-zheng PANG~(2,3) Chao-shu TANG~(3,5) Jing ZHANG~(2,3,6) 1 institute of Cardiovascular Disease Research,The First Hospital of Peking University,Beijing 100034,china 3 Key Laboratory of molecular Cardiovascular Science,Ministry of Education,Beijing 100083,china 4 Department of Pathophysiology,Capital institute of Medicine,Beijing 100054,china 5 Department of Physiology Health Center of Medical sciences,Peking University,Beijing 100083,china institute of Cardiovascular Disease Research The First Hospital of Peking University Beijing China Key Laboratory of molecular Cardiovascular Science Ministry of Education Beijing China Department of Pathophysiology Capital Institute of Medicine Beijing China Department of Physiology Health Center of Medical Sciences Peking University Beijing China

Aim:To investigate effects of taurine on ischemia/reperfusion(I/R)-induced com-partment syndrome in rabbit hind ***:Rabbits underwent femoralartery occlusion after ligation of branches from terminal aorta to femoral *** a 7-h ischemia,reperfusion was established with the use of heparinizedpolyethylene *** received taurine(1 g/kg)or normal saline(control)by iv infusion 10 min before shunt *** reperfusion,anterior com-partment pressure(ACP)was monitored continuously in the left lower *** muscle triphenyltetrazolium chloride(TTC)level,taurine contentand myeloperoxidase activity were *** stress was induced in thein vitro gastrocnemius muscle slices by free radical generating systems(FRGS),and the malondialdehyde content was measured in presence or absence of ***:After 7 h of ischemia,none of the parameters that we measured weredifferent from those before ischemia,except that TTC reduction decreased by80%.In the control group,after 2 h of reperfusion,ACP increased 4.5-fold,andgastrocnemius muscle taurine content was reduced by 33%.In taurine-treatedanimals,at 2 h reperfusion,the mean arterial blood pressure and heart rate wereincreased,by 6% and 10%.ACP decreased by 39%,muscle edema decreased by16%,TTC reduction increased by 150%,and lactate dehydrogenase decreased by36% compared to control *** and muscle taurine content increased by70% and 88%,*** the taurine-treated group,at 2 h repeffusion,plasmamalondialdehyde and conjugated diene content were decreased by 38% and 23%,respectively,and muscle malondialdehyde and conjugated diene content decreasedby 22% and 30%,respectively compared to the control *** 2 h reperfusion,myeloperoxidase activity was increased 3.5-fold in control *** the in vitrostudy,taurine decreased malondialdehyde content in muscle slices incubatedwith hypochlorous acid in a dose-dependent manner,but there was no changewhen incubated

关键词： taurine compartment syndromes reperfu sion injury

Formation of super-concentrated hydrochloric acid in the third phase in tertiary amine N235-PtCl_6^(2-)-HCl system and its influences on the Pt microemulsion extraction

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Science china Chemistry 2009年第11期52卷 1825-1834页

作者： HUANG Kun1,CHEN Jing1,ZHANG ChengFeng1,2,LI ZhiHong3,PAN QingHua1,SUN Yan1,LIU ShaoXuan1,LIU XueXin2,LI WeiHong1,YANG ZhanLan1,WENG ShiFu1,HU TianDou3,XU YiZhuang1 & WU JinGuang1 1 College of Chemistry and molecular Engineering,Peking University,Beijing 100871,china 2 institute of Chemistry,Chinese Academy of sciences,Beijing 100190,china 3 institute of High Energy Physics,Chinese Academy of sciences,Beijing 100049,china College of Chemistry and molecular Engineering Peking University Beijing China institute of Chemistry Chinese Academy of Sciences Beijing China institute of High Energy Physics Chinese Academy of Sciences Beijing China

In this paper,we have investigated the formation of the third-phase in tertiary amine(N235)-PtCl62--HCl system and the microscopic phase structural evolution of platinum-loaded organic phases before and after the occurrence of the *** third-phase is characterized by various spectroscopic techniques,and the small angle X-ray scattering(SAXS) experiments demonstrate the appearance of nano-aggregates,i.e.,water-in-oil reversed micelles,in the third *** experimental results indicate that(1) formation of the third phase is related to the aggregation behaviors of nano-reversed micelles in which a super-concentrated hydrochloric acid formed with the H+ to H2O molar ratio being much higher than that of the conventional 37 wt% saturated hydrochloric acid.(2) The occurrence of the super-concentrated HCl results in a great amount of H+ and Cl-ions enriched and confined within the nano-water pools of W/O reversed micelles in third ***,the coordination behaviors of platinum complex ions in that super-concentrated hydrochloric acid are very different from their corresponding behaviors in bulk aqueous *** is possible that H+ ions participate in the formation of such complexes as HmPtCl6z+ in the super-concentrated hydrochloric acid.(3) The relative contents of various HmPtCl6z+ complexes are different corresponding to the H+ ion concentrations in confined nanowater *** association ability of the acidified tertiary amine N235 molecules(R3NH+) with various HmPtCl6z+ complexes plays an important role in affecting the platinum extraction behaviors.

关键词： solvent extraction third phase super-concentrated hydrochloric acid tertiary amine platinum

Cloning and characterization of vernalization-related gene (ver203F) cDNA 3'end

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Chinese Science Bulletin 1999年第14期44卷 1289-1294页

作者： YONG Weidong, CHONG Kang , LIANG Tiebing, XU Zhihong , TAN Kehui and ZHU Zhiqing Research Center for molecular and Developmental Biology, institute of Botany, Chinese Academy of sciences , Beijing 100093, china Shanghai institute of Plant Physiology , Chinese Academy of sciences , Shanghai 200032, china Corresponding authors Research Center for molecular and Developmental Biology Institute of Botany Chinese Academy of Sciences Beijing China Shanghai institute of Plant Physiology Chinese Academy of Sciences Shanghai China

Based on the cDNA fragment sequence of vernalization-related gene verc203 cloned by differential screening in our lab, the 5′primer has been designed. The cDNA 3′end of ver203 gene (1 197 bp) has been cloned by the RACE method. And it is identified by Northern blotting that its expression is special in vernalization treatment. After comparing the sequence in the nucleotide sequence databases of Genbank, EMBL and DDBJ, the gene has homology with Hordeum vulgare jesmonate-induced protein gene. It is suggested that this gene might be related to the signal transduction mediated by jamonate.

关键词： wheat vernalization-related gene cDNA 3’ end RACE.