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排序方式: 共有455条查询结果,搜索用时 15 毫秒
1.
Over the last two decades many strategies have been planned to design specific drugs for rare diseases to target their action
at the DNA level. Advancements in our understanding of the interactions of small nonpeptide molecules with DNA have opened
the doors for “rational” drug design. Special methods have now been developed to give accurate account of the precise location
of ligand-DNA adducts on target DNA. We are now in a position to think of designing ligands that recognize particular sequences
of base pairs. This work will allow us to enter into a new era of gene therapy for diseases like Cystic fibrosis, Alzheimer’s
disease and many related disorders at genetic level. These ligands can also be employed in the treatment of various types
of cancers. They may also be useful as highly specific probes to locate particular sequences in the genomic DNA. 相似文献
2.
Marye Anne Fox Arvind C. Ranade Ismail Madany 《Journal of organometallic chemistry》1982,239(2):269-277
High yield nucleophilic addition ensues upon mixing tetrahydrofuran solutions of benzyllithium or cyclooctadienyllithium and anthracene at low temperatures At least part of this addition proceeds by a single electron transfer pathway. Photolysis of the resulting adducts leads to the elimination of lithium hydride, giving net nucleophilic substitution in approximately 50% yield. The analogous reaction fails with naphthalene, where photolysis of the organolithium/ arene mixture leads to dimeric products derived from the organolithium. 相似文献
3.
This paper is a straightforward generalization of Maierle-Harris proposal regarding parity implications on the superpositions of chiral states of a molecule. It is shown that the inclusion of electric quadrupole and magnetic dipole interactions removes several of restrictions on the preparation of superpositions of mid R:L and mid R:R states of a chiral molecule. It is also found that the dephasing of mid R:L and mid R:R superpositions, due to the spontaneous emission from the chiral molecule, has opposing contributions from electric quadrupole-magnetic dipole and electric dipole interactions. 相似文献
4.
Arvind?KumarEmail author V.?P.?Mohandas Rahul?Sanghavi P.?K.?Ghosh 《Journal of solution chemistry》2005,34(3):333-342
The thermodynamic, volumetric, transport, and surface properties, solubilities, densities, viscosities, electrical conductivities, and surface tensions of calcium sulfate dihydrate in aqueous sodium chloride solutions have been measured at 35 C, with a view to determine the ionic interactions that occur in these solutions. The experimental density values have been used to calculate the mean apparent molar volumes of the ternary mixtures. Viscosity values have been analyzed using different empirical equations and the experimental values of the viscosity were combined with conductivity to yield the Walden product. Molar surface energies have been computed using experimental surface tension data. The experimental data have been fitted to polynomial equations by a least-squares analysis to obtain the coefficients and their standard errors. Results have been examined in the light of structure making or structure breaking effects of the various ions present in the solutions. 相似文献
5.
Gupta Madan Mohan Srivastava Alpana Tripathi Arvind Kumar Misra Himanshu Verma Ram Kishore 《平面色谱法杂志一现代薄层色谱法》2006,19(4):282-287
JPC – Journal of Planar Chromatography – Modern TLC - High-performance thin-layer chromatography (HPTLC) has been used for normal-phase separation of the components of hexane,... 相似文献
6.
John B. Hynes Alenka Tomai
Arvind Kumar Veena Kumar James H. Freisheim 《Journal of heterocyclic chemistry》1991,28(8):1981-1986
A series of thirty eight 2,4-diaminoquinazolines having diverse substitution patterns on the aromatic ring was evaluated for inhibitory activity against dihydrofolate reductase (DHFR) obtained from a human lymphoblast cell line. Many of these compounds were also evaluated as inhibitors of rat liver DHFR under the same experimental conditions. In most instances the results obtained with each enzyme were comparable indicating that the rodent enzyme is a suitable model for the human DHFR as far as the determination of I50 values is concerned. The results demonstrate that relatively simple 5-substituted- or 5,6-disubstituted-2,4-diaminoquinazolines can be potent DHFR inhibitors. The presence of a nonpolar substituent at position 7 or 8 was highly detrimental to inhibitory potency. 相似文献
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9.
Arvind Samariya S.N. Dolia Arun S. Prasad P.K. Sharma S.P. Pareek M.S. Dhawan Sudhish Kumar 《Current Applied Physics》2013,13(5):830-835
CaFe2O4 nanocrystalline powders were synthesized through sol–gel treatment in which the stoichiometric mixing of various nitrates involving calcium and iron in presence of citric acid was performed. Subsequently, the as prepared sample was annealed at various temperatures in order to obtain the fine distribution of size including the bulk counterpart. The samples were then characterized using powder X-ray diffraction followed by 57Fe Mössbauer spectroscopy, SQUID as well as vibrating sample magnetometry. The results of spectroanalyses revealed that the samples were formed in single phase cubic spinel structure and exhibits room temperature superparamagnetism, except the bulk one, which crystallizes in characteristic orthorhombic structure of CaFe2O4 and displays trivial coercivity and remanent magnetization at room temperature. 相似文献
10.
Eric C. Chi Liuyi Hu Arvind K. Saibaba Arvind U. K. Rao 《Journal of computational and graphical statistics》2019,28(1):36-47
We consider the problem of performing matrix completion with side information on row-by-row and column-by-column similarities. We build upon recent proposals for matrix estimation with smoothness constraints with respect to row and column graphs. We present a novel iterative procedure for directly minimizing an information criterion to select an appropriate amount of row and column smoothing, namely, to perform model selection. We also discuss how to exploit the special structure of the problem to scale up the estimation and model selection procedure via the Hutchinson estimator, combined with a stochastic Quasi-Newton approach. Supplementary material for this article is available online. 相似文献