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1.
LanYong Zhang Ying Wan Jiong Zhang Di Li LiHua Wang ShiPing Song ChunHai Fan 《中国科学B辑(英文版)》2009,52(6):746-750
A highly sensitive method for the detection of a breast cancer-associated BRCA-1 gene is reported. The detection is based
on a classical sandwich-type assay using horseradish peroxidase (HRP) as a catalytic label and electrodeposited Os2+/3+ conducting polymer (PAA-PVI-Os) as a redox mediator. Target DNA could be detected by the HRP-catalyzed reduction of H2O2, leading to a limit of detection as low as 10 fM.
Supported by the National Natural Science Foundation of China (Grant Nos. 20725516, 20704043, 20873175 & 20805055), Shanghai
Municipal Commission for Science and Technology (Grant Nos. 0752nm021 & 07ZR14136), Ministry of Science and Technology (Grant
Nos. 2006CB933000, 2007CB936000 & 2007AA06A406), Ministry of Health (Grant No. 2009ZX10603), and China Postdoctoral Science
Foundation and Shanghai Postdoctoral Scientific Program (Grant No. 07R214160). 相似文献
2.
The water-soluble Ag nanoparticles capped with novel zwitterionic thioalkylated phosphorylcholine were synthesized. The Ag
nanoparticles showed remarkable stability in saline media with salt concentrations as high as 2.0 mol/L and plasma using UV-vis
absorption spectroscopy. Similarly, compared with tiopronin and citrate-protected Ag nanoparticles, the zwitterionic phosphorylcholine
Ag nanoparticles did not precipitate out of solution when charged polyelectrolytes or biopolymers were added. The zwitterionic
phosphorylcholine might be a better ligand for stabilizing metal nanoparticles.
Supported by the National Natural Science Foundation of China (Grant Nos. 20774082 and 50703036), National High Technology
Research and Development Program of China (Grant Nos. 2006AA03Z329 and 2006AA032444) and Science and Technology Projects of
Zhejiang Province (Grant No. 2007C24G2010020) 相似文献
3.
The polarity-sensitive fluorescent probe, 3-(4-chloro-6-p-glyoxalphenoxy-1,3,5-triazinylamino)-7- (dimethylamino)-2-methylphenazine, was used to analyze the local structure of apo-α-lactalbumin by detecting the polarity and conformational changes of the arginine residue (Arg10) domain. The polarity of the Arg10 domain in both native and heat-denatured apo-α-lactalbumin was determined, which corresponds to a dielectric constant of 16, and the hydrophobic core near the Arg10 was found to be conservative for h... 相似文献
4.
A novel typography technique was developed to in situ synthesize oligonucleotide arrays on glass slide, which has the celerity, high spatial resolution, lower cost, reliable operation,
and high synthetic efficiency. The principle and process of the typography technique for fabricating gene-chips have been
described in detail. A suit of poly(terafluoroethylene) devices for synthesizing oligonucleotide arrays were designed and
prepared, and the fiber tubes with a number of nano-or micron-channels were employed. The oligonucleotide arrays of 16 and
160 features with four different probes were synthesized using the typography technique. The four specific oligonucleotide
probes including the matched and the mismatched by the fluorescent target sequence gave obviously different hybridization
fluorescent signals. It was indicated that the gene-chip fabricated by the typography method could be used to rapidly screen
single-nucleotide polymorphisms (SNP) and to detect mutations.
Supported by the National Natural Science Foundation of China (Grant Nos. 60571032, 60571001, 90606027 and 60121101), the
National Hi-Tech Research and Development Program of China (Grant No. 2006AA03Z357), the Natural Science Foundation of Hunan
Province (Grant Nos. 04jj40023 and 06JJ4012) and the Natural Science Foundation of Guangdong Province (Grant No. 04008782) 相似文献
5.
Peptidomimetics with three types, as the structural or functional mimetics of natural active peptides, can preserve the bioactivity
and improve the bioavailability and the specificity towards the targets of the lead peptides. Peptidomimetics of high bioactivity
can be designed through various ways including conformation restriction, modification and non-peptide design. Recently the
concentration on the development of cancer chemotherapeutic drugs was transferred from cytotoxic drugs to target-based drugs,
and many proteases and peptidases that play key roles in the process of tumor genesis and development was discovered, which
means that peptidomimetics as potential cancer chemotherapeutic drugs should be paid close attention to. Our laboratory has
focused on the development of small-molecule peptidomimetic inhibitors of APN, MMPs and HDACs as target-based anticancer agents.
These three zinc-dependent metalloproteinases play very important roles in the process of tumor genesis, invasion, metastasis,
angiogenesis and matrix degradation, so small-molecule peptidomimetic inhibitors based on them would be quite potential in
the development of chemotherapeutic drugs with high selectivity.
Supported by the National High Technology Research and Development Program of China (863 Project) (Grant No. 2007AA02Z314),
the National Natural Science Foundation of China (Grant Nos. 90713041 & 30772654), and the Doctoral Fund of Ministry of Education
of China (Grant No. 20060422029) 相似文献
6.
AUMILER Damir 《中国科学B辑(英文版)》2009,52(8):1148-1153
The intersystem crossing and isomerization dynamics of free-Cy3, Cy3-ssDNA, free-Cy5 and Cy5-ssDNA are obtained through simple
analysis of rapid on/off blinking from single molecule fluorescence intensity time-traces and the fluorescence correlation
spectroscopy (FCS). The on- and off-times observed in fluorescence time traces of single cyanine dyes are due to the formation
of the triplet state and isomerization, where both the interaction with DNA and long central polymethine chain of cyanine
dyes increase the barriers of isomerization, leading to long off-time. The results indicate that the single molecule fluorescence
fluctuation together with the resulting second autocorrelation analysis are powerful methods for determining the triplet state
and isomerization dynamics, which could be the simple techniques and complementary to other spectroscopic techniques, such
as fluorescence decay measurement and laser flash photolysis to study the photophysical processes of complex molecules.
Supported by the National Natural Science Foundation of China (Grant Nos. 20773139, 20833008 & 20825314), and State Key Project
for Fundamental Research (Grant Nos. 2006CB806000 & 2007CB815200) 相似文献
7.
Imine-bridged TTF-π-pyridine derivatives, 2NTTF, 3NTTF and 4NTTF, were synthesized and the cation-binding study was performed.
It is noted that with the addition of the micromolar concentration of Pb2+ to the solution, these compounds display remarkable changes in solution color, 1H NMR spectra and electrochemical properties. The nitrogen atom of the imine-bridge in 2NTTF not only serves as a π-conjugated
spacer but also participates in the sensing and coordinating properties.
Supported by the National Natural Science Foundation of China (Grant Nos. 20732007, 20728506 & 20672122), the Ministry of
Science and Technology of China (Grant Nos. 2006CB806105, 2007CB808004, 2007CB936001 & 2009CB-22008) and the Bureau for Basic
Research of the Chinese Academy of Sciences 相似文献
8.
MIAO Ru XU ZhenXiang HUANG ZhiTang & CHEN ChuanFeng Beijing National Laboratory for Molecular Science 《中国科学B辑(英文版)》2009,52(4):505-512
A series of novel N,O-type chiral ligands derived from enantiopure inherently chiral calix[4]arenes containing quinolin-2-yl-methanol moiety in
the cone or partial-cone conformation have been synthesized and characterized. Moreover, they have been applied to the catalytic
asymmetric addition of diethylzinc to benzaldehyde, which represents the first example that the inherently chiral calixarene
can be used as the chiral ligands for the catalytic asymmetric synthesis.
Supported by the National Natural Science Foundation of China (Grant Nos. 20625206 & 20372064), the National Basic Research
Project (Grant Nos. 2007CB808000 & 2008CB617501), and the Chinese Academy of Sciences 相似文献
9.
DFT study of difference caused by catalyst supports in Pt and Pd catalysis of oxygen reduction reaction 总被引:1,自引:0,他引:1
Li Li ZiDong Wei Yi Zhang XueQiang Qi MeiRong Xia Jie Zhang ZhiGang Shao CaiXin Sun 《中国科学B辑(英文版)》2009,52(5):571-578
Based on an experimental phenomenon that catalytic activity of Pt and Pd for oxygen reduction reaction (ORR) changes with
catalyst supports from C to TiO2, density function theory (DFT) was used to elucidate the cause behind the difference in catalysis caused by catalyst supports.
First, factors closely associated with the first electron transfer of the ORR were assessed in the light of quantum chemistry.
Then intermediate (atomic oxygen, O) adsorption strength on the catalyst surface was calculated. The results show that, in
terms of minimum energy difference, the best orbital symmetry match, and the maximum orbital overlap, TiO2 does bring about a very positive effect on catalysts Pd/TiO2 for the first electron transfer of the ORR. Especially, TiO2 remarkably expands the space size of Pd/TiO2 HOMO orbital and improves orbital overlap of Pd/TiO2 HOMO and O2 LUMO. The analysis of deformation density and partial density of state shows that the strong interaction between Pt and Ti
leads to a strong adsorption of intermediate O on Pt/TiO2, but the strong interaction between Pd and surface O causes positive net charge of Pd and a weak adsorption of intermediate
O on Pd/TiO2. Thus, the ORR can proceed more smoothly on Pd/TiO2 than Pt/TiO2 in every respect of maximum orbital overlap and rate delay by intermediate O. The research also discloses that several factors
lead to less activity of TiO2-supported Pt and Pd catalysts than the C-supported ones for the ORR. These factors include the poor dispersion of Pt and
Pd particles on TiO2, poor electric conduction of TiO2 carrier itself, and bigger energy difference between HOMO of TiO2-carried metallic catalysts and LUMO of O2 molecule due to electrons deeply embedded in the semiconductor TiO2 carrier.
Supported by the National Natural Science Foundation of China (Grant No. 20676156), the Chinese Ministry of Education (Grant
No. 307021), the National 863 Program (Grant Nos. 2006AA11A141 and 2007AA05Z124), and the Chongqing Sci &Tech Key Project
(Grant No. CSTC2007AB6012) 相似文献
10.
This work successfully prepared nanohybrids by in situ atom transfer radical polymerization (ATRP) of styrene from titanate nanotubes (TNTs). Fourier-transform infrared (FT-IR),
pronton nuclear magnetic resonance spectroscopy (1H NMR), and thermal gravimetric analysis (TGA) were used to verify the successful graft of polystyrene (PS) chains from TNTs.
Transmission electron microscopy (TEM) displayed that the obtained PS-g-TNTs nanohybrids had a core-shell structure of TNT core and PS shell. The grafted PS content was well controlled and increased
with increasing of the monomer/initiator ratio. Further copolymerization of tert-butyl acrylate (tBA) from the surface of PS-g-TNTs was studied, illustrating the “living” characteristics of the surface-induced ATRP method used in this work.
Supported by the Special Funds for Major State Basic Research Projects (Grant No. 2005CB623803), the National Basic Research
Program (Grant Nos. 2007CB808000 & 2009CB930400), the National Natural Science Foundation of China (Grant Nos. 50633010 &
20874060), the Program for New Century Excellent Talents in University (Grant No. NCET-07-0558), the Basic Research Foundation
of Shanghai Science and Technique Committee (Grant No. 07DJ14004), and Shanghai Leading Academic Discipline Project (Grant
No. B202). 相似文献
11.
A representative acetate-(5-methylimidazole)-methanol system has been employed as a model of catalytic triad in serine protease
to validate the formation processes of low-barrier H-bonds (LBHB) at the B3LYP/6-311++G** level of theory, and variable H-bonding
characters from conventional ones to LBHBs have been represented along with the proceedings of proton transfer. Solvent effect
is an important factor in modulation of the existence of an LBHB, where an LBHB (or a conventional H-bond) in the gas phase
can be changed into a non-LBHB (an LBHB) upon solvation. The origin of the additional stabilization energy arising from the
LBHB may be attributed to the H-bonding energy difference before and after proton transfer because the shared proton can freely
move between the proton donor and proton acceptor. Most importantly, the order of magnitude of the stabilization energy depends
on the studied systems. Furthermore, the nonexistence of LBHBs in the catalytic triad of serine proteases has been verified
in a more sophisticated model treated using the ONIOM method. As a result, only the single proton transfer mechanism in the
catalytic triad has been confirmed and the origin of the powerful catalytic efficiency of serine proteases should be attributed
to other factors rather than the LBHB.
Supported by the National Natural Science Foundation of China (Grant Nos. 20633060 & 20573063), the Natural Science Foundation
of Shandong Province (Grant No. Y2007B23), the Scientific Research Foundation of Qufu Normal University (Grant Nos. Bsqd2007003
and Bsqd2007008), and the State Key Laboratory of Physical Chemistry of Solid Surfaces (Xiamen University) 相似文献
12.
MEIER Herbert 《中国科学B辑(英文版)》2009,52(7):1051-1056
A rapid and efficient synthesis of novel dendrimer homotriptycenes is presented. The dendronized 9,10-dihydroanthracen-9-ols 4, having high electron densities in the benzene rings of the Fréchet-type dendrons, exhibited in the presence of acid a quantitative transannular ring closure to the corresponding dendritic homotriptycenes. The electron-donating Fréchet-type dendrons enabled the intramolecular FC alkylation by a regioselective 1,7-elimination of H2O. 相似文献
13.
JingJing Zhang Ying Shao Li Wei Ying Li Xin Sheng Fang Liu GuoYuan Lu 《中国科学B辑(英文版)》2009,52(4):402-414
The design of artificial nucleases and nuclease mimics has attracted extensive attention and made great progress due to their
significant scientific meanings and potential application in the field of gene medicine and molecular biology. This paper
reviews recent progress in the investigation of artificial nuclease, including “bifunctional cooperative catalysis”, “dinuclear
synergistic catalysis”, “metal-free catalysis”, and especially, the studies of aza-crown ethers as artificial nucleases and
their interaction with DNA.
Supported by the National Natural Science Foundation of China (Grant Nos. 20872061 & 20372032) and the National Basic Research
of China (Grant No. 2007CB925103) 相似文献
14.
ZHU HaoMiao LI Bo LI Li SHEN Jian Jiangsu Engineering Research Center for Bio-medical Function Materials Nanjing Normal University Nanjing China Jiangsu Research Center of Surface Interface Chemical Engineering Technology Nanjing University Nanjing China 《中国科学B辑(英文版)》2008,51(1):78-85
Molecular dynamics simulations are applied to the initial stage of polyalanine13 conformational transi- tion from α-helix to random coil in aqueous environment and the interaction of polyalanine13 with zwitterionic and hydrophobic surfaces respectively in the same condition. The analysis of secondary structure, hydrogen bonds, RMSD, dihedral distribution, and the degree of adsorption are performed. The results show that zwitterionic structure maintains the natural behavior of polyalanine13 in water to a better extent, which should be an indirect proof of the hypothesis of "maintain of normal structure." 相似文献
15.
Polychlorinated biphenyls(PCBs) can antagonize human pregnane X receptor(hPXR) activation.Such chemicals could pose a serious threat to the reproductive and developmental ability of humans.The quantitative structure activity relationship(QSAR) provides a promising method for the estimation of PCBs’ antagonistic activity.In this investigation,a QSAR model was developed by using heuristic method and best subset modeling(r2 = 0.873,q2LOO=0.742).The built model was validated externally by splitting the original data set into training and prediction sets.The results of the model derived are as follows:r2 = 0.907,q2LOO=0.709,r2pred=0.676,suggesting developed QSAR model had good robustness and predictive ability.The applicability domain(AD) of the model was assessed by Williams plot.The antagonistic activity(?logKi) of 108 PCBs,which are unavailable by experiment at present,was predicted within the applicability domain of the model.The critical structural features related to the activity of PCBs were identified. 相似文献
16.
HU RenTao Lü LiangFei RUAN BanFeng WANG Peng ZHANG MingLiang ZHOU HongPing LI ShengLi WU JieYing & TIAN YuPeng Department of Chemistry Chemical Engineering Key Laboratory of Functional Inorganic Materials Chemistry of Anhui Province Anhui University Hefei China 《中国科学B辑(英文版)》2009,52(8):1210-1215
Two carbazole-based polymerization initiators possessing blue fluorescence emission have been synthesized via Wittig reaction
in the solid phase at room temperature. Two-photon excited fluorescence (TPEF) spectra for them were investigated under 800
nm fs laser pulse and two-photon absorption cross sections were determined by the Z-scan technique. Then two-photon initiating
polymerization (TPIP) microfabrication experiments were successfully carried out. Three-dimensional lattice and artificial
defects were gained, indicating that they were viable candidates for the two-photon polymerization initiator in practical
application of microfabrication.
Supported by the National Natural Science Foundation of China (Grant Nos. 50532030, 20771001 & 50703001), and Team for Scientific
Innovation of Anhui Province (Grant No. 2006KJ007TD) 相似文献
17.
Review on supermolecules as chemical drugs 总被引:3,自引:0,他引:3
ChengHe Zhou LinLing Gan YiYi Zhang FeiFei Zhang GuangZhou Wang Lei Jin RongXia Geng 《中国科学B辑(英文版)》2009,52(4):415-458
Supramolecular medicinal chemistry field has been a quite rapidly developing, increasingly active and newly rising interdiscipline
which is the new expansion of supramolecular chemistry in pharmaceutical sciences, and is gradually becoming a relatively
independent scientific area. Supramolecular drugs could be defined as medicinal supermolecules formed by two or more molecules
through non-covalent bonds. So far a lot of supermolecules as chemical drugs have been widely used in clinics. Supermolecules
as chemical drugs, i.e. supramolecular chemical drugs or supramolecular drugs, which might have the excellences of lower cost,
shorter period, higher potential as clinical drugs for their successful research and development, may possess higher bioavailability,
better biocompatibility and drug-targeting, fewer multidrug-resistances, lower toxicity, less adverse effect, and better curative
effects as well as safety, and therefore exhibit wide potential application. These overwhelming advantages have drawn enormous
special attention. This paper gives the definition of supramolecular drugs, proposes the concept of supramolecular chemical
drugs, and systematically reviews the recent advances in the research and development of supermolecules, including organic
and inorganic complex ones as chemical drugs in the area of antitumor, anti-inflammatory, analgesic, antimalarial, antibacterial,
antifungal, antivirus, anti-epileptic, cardiovascular agents and magnetic resonance imaging agents and so on. The perspectives
of the foreseeable future and potential application of supramolecules as chemical drugs are also presented.
Supported by the Southwest University (Grant Nos. SWUB2006018 & XSGX0602), the Natural Science Foundation of Chongqing (Grant
Nos. 2007BB5369 & 2006BB4341) and the Key Project from the Personnel Department of China (Grant No. 2002-99) 相似文献
18.
Interactions between a symmetrical tetramethyl-substituted cucurbit[6]uril (host: TMeQ[6]) and 1,ω-alkylenedipyridine (ω =
2, 4, 6, 8, 10) dicationic guests were investigated using 1H NMR spectroscopy and single crystal X-ray crystallography. In these inclusion complexes, combined cavity and portal binding
in TMeQ[6] were observed, and the length of the bridged alkylene was found to play an important role not only in balancing
the overall hydrophilic/hydrophobic interaction between the host and the guest, but also in defining the structure of the
resulting inclusion complexes. For the guest 1,2-ethylenedipyridine (Edpy), TMeQ[6] includes a positively charged pyridine
ring of Edpy to form an unsymmetrical inclusion complex; for the guest 1,4-butylenedipyridine (Bdpy), TMeQ[6] includes a positively
charged pyridine ring of Bdpy, but the different competitive interactions in and between the related inclusion complexes could
lead to a fast exchange between the hosts and guests. For the guests with longer bridge chains, such as 1,6-hexamethylenedipyridine
(Hdpy) or 1,8-octylenedipyridine (Odpy), a stable pseudorotaxane inclusion complex is formed by combining the hydrophobic
cavity and the outer portal dipole-ion interactions. However, for 1,10-decatylenedipyridine (Ddpy), the two TMeQ[6] host molecules
include the two end pyridine rings of Ddpy and form a dumbbell inclusion complex.
Supported by the National Natural Science Foundation of China (Grant Nos. 20662003 & 20767001), the International Collaborative
Project of Guizhou Province (Grant No. 2007400108), the Science Technology Fund of Guizhou Province (Grant No. J-2008-2012)
and the Natural Science Youth Foundation of Guizhou University (Grant No. 2007-005) 相似文献
19.
Synthesis,structure and nonlinear optical properties of two novel two-photon absorption chromophores
Two triphenylamine-based derivatives that can be used as two-photon absorption chromophore,tris{4-[4-(3-trifluoromethyl-3-oxopanoyl)]phenyl}amine (1) and tris{4-[4-(3-phenyl-3-oxopanoyl)] phenyl} amine (2) were successfully synthesized and fully characterized by elemental analysis,IR,1H NMR and MS. The single crystal X-ray diffraction analysis showed that the molecules possess D-(π-A)3 structures. One-and two-photon absorption and fluorescence in various solvents were experimentally investigated. A data rec... 相似文献
20.
LiXi Zeng YuJian He ZhiFeng Dai Jian Wang CaiQi Wang YongGang Yang 《中国科学B辑(英文版)》2009,52(8):1227-1234
Supramolecular chirality and molecular self-assembly are important and interesting phenomena in living and non-living systems.In this work,supramolecular chirality of achiral pseudoisocyanine(PIC) J-aggregates was successfully induced by D-,L-phenylalanine(Phe) and other amino acids in NaCl solution.The chiral J-aggregates showed a characteristic,induced circular dichroism(ICD) in the visible region of J-band chromophore which depends on the absolute configuration,concentration and side groups of α-amino ac... 相似文献