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61.
A graph G is said to be 2-divisible if for all (nonempty) induced subgraphs H of G, can be partitioned into two sets such that and . (Here denotes the clique number of G, the number of vertices in a largest clique of G). A graph G is said to be perfectly divisible if for all induced subgraphs H of G, can be partitioned into two sets such that is perfect and . We prove that if a graph is -free, then it is 2-divisible. We also prove that if a graph is bull-free and either odd-hole-free or P5-free, then it is perfectly divisible. 相似文献
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Kumar RS Kanmani P Yuvaraj N Paari KA Pattukumar V Thirunavukkarasu C Arul V 《Applied biochemistry and biotechnology》2012,166(3):620-631
The relationship between antioxidant and anticancer properties of probiotic bacterium strain Lactobacillus plantarum AS1 (AS1) in colon cancer induced by 1,2-dimethylhydrazine (DMH) has been studied. In this study, an increased level of lipid
peroxide (LPO) products and increased activities of antioxidant enzymes (superoxide dismutase, catalase and glutathione-S transferase) and marker enzymes (alkaline phosphatase and acid phosphatase) in colon and plasma of cancer-bearing animals
have been observed. AS1 was supplemented either before initiation or during initiation and selection/promotion phases of colon
carcinogenesis and was found to be effective in altering lipid peroxidation and antioxidant enzyme activities and marker enzymes
to a statistically significant level measured either in the colon and in the plasma. These alterations inclined towards normal
in a time-dependent manner on AS1 supplementation. The mean tumor volume diameter and total number of tumors were found to
be statistically decreased in AS1 pre- and post-treated rats. Furthermore, histopathological examination shows remarkable
difference between control and treated groups. The in vitro antioxidant assay shows that AS1 has promising antioxidant property.
These results demonstrate that AS1 strain can modulate the development of DMH-induced rat colon carcinogenesis through an
antioxidant-dependent mechanism. 相似文献
64.
Sivaraman B Mebel AM Mason NJ Babikov D Kaiser RI 《Physical chemistry chemical physics : PCCP》2011,13(2):421-427
The formation of six ozone isotopomers and isotopologues, (16)O(16)O(16)O, (18)O(18)O(18)O, (16)O(16)O(18)O, (18)O(18)O(16)O, (16)O(18)O(16)O, and (18)O(16)O(18)O, has been studied in electron-irradiated solid oxygen (16)O(2) and (18)O(2) (1?∶?1) ices at 11 K. Significant isotope effects were found to exist which involved enrichment of (18)O-bearing ozone molecules. The heavy (18)O(18)O(18)O species is formed with a factor of about six higher than the corresponding (16)O(16)O(16)O isotopologue. Likewise, the heavy (18)O(18)O(16)O species is formed with abundances of a factor of three higher than the lighter (16)O(16)O(18)O counterpart. No isotope effect was observed in the production of (16)O(18)O(16)O versus(18)O(16)O(18)O. Such studies on the formation of distinct ozone isotopomers and isotopologues involving non-thermal, non-equilibrium chemistry by irradiation of oxygen ices with high energy electrons, as present in the magnetosphere of the giant planets Jupiter and Saturn, may suggest that similar mechanisms may contribute to the (18)O enrichment on the icy satellites of Jupiter and Saturn such as Ganymede, Rhea, and Dione. In such a Solar System environment, energetic particles from the magnetospheres of the giant planets may induce non-equilibrium reactions of suprathermal and/or electronically excited atoms under conditions, which are quite distinct from isotopic enrichments found in classical, thermal gas phase reactions. 相似文献
65.
ONO pincer‐type palladium(II) complexes of heterocyclic hydrazone: Synthesis,characterization and biological evaluation
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Thangavel Thirunavukkarasu Hazel A. Sparkes Karuppannan Natarajan V.G. Gnanasoundari 《应用有机金属化学》2018,32(8)
Two new Pd(II) complexes of N′‐(4‐(diethylamino)‐2‐hydroxybenzylidene)furan‐2‐carbohydrazide were synthesized and characterized using various spectral methods. The structure of one of the complexes was determined using single‐crystal X‐ray diffraction. DNA and protein binding affinities of the synthesized compounds were examined using UV–visible and fluorescence titration method. In addition, the in vitro cytotoxicity of the compounds was evaluated against A549 (lung cancer) and MCF7 (breast cancer) cell lines using the MTT assay method. 相似文献
66.
R. Agilandeswari A. Aditya Prasad S. Sivaraman S. Kalainathan 《Molecular Crystals and Liquid Crystals》2016,625(1):238-252
bis(2-nitroaniline) picrate (BNP) single crystals was grown by slow evaporation growth technique using mixed solvent system with methanol–acetone (1:1, v/v) at a constant temperature, and the structure was interpreted by single crystal X-ray, Power Diffraction (XRD) analysis. Inter- and intramolecular hydrogen bonding interactions were interpreted, and crystal cohesion was architectured by N-H···O, O-H···O, C-H···N, H···H, O···O, and π···π staking interactions. All intermolecular interactions occurring in the crystal lattice were calculated using fingerprint analysis. Interaction strengths were graphically illustrated by the Hirshfeld surface analysis. The band gap energy of BNP was estimated by the application of the Kubelka–Munk algorithm. Nonlinear optical behavior was confirmed by the Kurtz–Perry technique. Optimized geometry was derived by the density functional theory calculations. The first-order molecular hyperpolarizability (β) and excited state energies were estimated by the time-dependent density functional theory analysis. 相似文献
67.
Sivaraman BalasubramaniamHarikrishna Kommidi Indrapal Singh Aidhen 《Tetrahedron letters》2011,52(21):2683-2686
A successful strategy based on the synthetic equivalent containing Weinreb amide functionality for the convenient access to 1,1-diarylethenes in general and for the isocombretastatin analogues in particular has been developed from the commercially available glyoxalic acid. The convenience with which the structural variations can be made in assembling the aryl residues shows generality associated with the developed strategy. The intermediates also provide access to 1,2,2-triarylethanones, represented by the synthesis of advanced intermediate of tamoxifen. 相似文献
68.
Pandya BA Dandapani S Duvall JR Rowley A Mulrooney CA Ryba T Dombrowski M Harton M Young DW Marcaurelle LA 《Tetrahedron》2011,67(34):6131-6137
Orthogonally protected chiral β-hydroxy-γ-amino acids can be accessed in >100 g quantities from readily available starting materials and reagents in three to four steps. These chiral synthons contain two adjacent stereocenters along with suitably protected functional groups (O-TBS, N-Boc) for downstream reactivity. Implementation of two existing aldol technologies allows rapid access to all possible stereoisomers of 1. The guiding principles during reaction optimization were reaction scalability and operational efficiency. Conversion of the amino acids to a variety of chiral building blocks in one to two steps demonstrates their synthetic utility. 相似文献
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