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A series of new chiral thiosemicarbazones derived from homochiral amines in both enantiomeric forms were synthesized and evaluated for their in vitro antiproliferative activity against A549 (human alveolar adenocarcinoma), MCF‐7 (human breast adenocarcinoma), HeLa (human cervical adenocarcinoma), and HGC‐27 (human stomach carcinoma) cell lines. Some of compounds showed inhibitory activities on the growth of cancer cell lines. Especially, compound 17b exhibited the most potent activity (IC50 4.6 μM) against HGC‐27 as compared with the reference compound, sindaxel (IC50 10.3 μM), and could be used as a lead compound to search new chiral thiosemicarbazone derivatives as antiproliferative agents. Chirality 27:177–188, 2015. © 2014 Wiley Periodicals, Inc.  相似文献   
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The optimization of regeneration protocol for different genotypes increases the yield in transformation studies. Cotyledon explants of watermelon [Citrullus lanatus (Thunb) Matsum & Nakai] cv Crimson Sweet were cultured on MS medium containing combinations of benzyl adenine (BA) (0, 5, 10, 20 µM) and indole-3-acetic acid (IAA) (0, 0.5, 5 µM). Maximum shoot growth and subsequent rooting from explants on regeneration medium were obtained from the media containing 10 µM BA + 0.5 µM IAA and 20 µM BA (75 and 78%) by direct organogenesis, respectively. Histological analysis showed that cell division was observed in the epidermal and subepidermal layers. Protuberant structures were observed in tissues between 7 and 12 days in culture. Meristematic structures were observed after 12days in culture which later developed into buds.  相似文献   
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Summary The paper discusses the problems of genetic aspects of plant mineral nutrition in the light of the results presented at the First and Second Symposia on ‘Genetic Aspects of Plant Mineral Nutrition’ organized in Beograd in 1982 and Madison in 1985, respectively. On the basis of the results, future directions of research are discussed. The papers deal with the concentration and content of mineral nutrients in different genotypes, physiological and biochemical aspects of the genetic specificity of plant mineral nutrition, relations between plant genotypes and nitrogen fixing micro-organism strains, as well as with some related problems which have been investigated to a lesser extent. Particular attention is paid to papers and problems referring to genetic and breeding research work linked with genetic aspects of plant mineral nutrition as well as the possibilities of developing new cultivars requiring certain soil and mineral nutrition conditions for their cultivation.  相似文献   
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The 40 kd lambda Integrase protein is shown to contain two autonomous DNA binding domains with different sequence specificities. Competition experiments in which the binding activity of Int is assayed through nuclease protection demonstrate the functional independence of the two DNA recognition specificities. Proteolytic cleavage of Int and footprinting analysis of the resulting two major peptides allow the physical separation and identification of two DNA binding domains: an amino-terminal peptide that interacts with "arm-type" sites and a carboxy-terminal peptide that binds to "core-type" sequences. In addition, the data suggest that the two domains can bind DNA simultaneously, consistent with a model in which Integrase would link two disparate DNA sequences.  相似文献   
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Summary Snake flask experiments were carried out as a preliminary study of fat formation byTrichoderma reesei (formallyviride) QM 9123 using a glucose based medium. The maximum quantity of fat production was 16% of the dry weight. The pH of the medium, as much as its composition, appeared to influence the quantity of fat that was produced. The fatty acids formed by the hydrolysis of the fats were found to be mainly unsaturated, with the 182 (linoleic) acid predominating.  相似文献   
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Summary This study investigates the effects of anticancer drugs and immunomodulating agents on the release of interleukin-6 (IL-6) from lipopolysaccharide-stimulated human peripheral blood mononuclear leucocytes in vitro. The addition of non-cytotoxic concentrations of Adriamycin (doxorubicin), vincristine and 4-OOH-cyclophosphamide (the in vitro active analogue of cyclophosphamide) resulted in suppression of IL-6 release. The drugs bleomycin, FK156 [d-lactoyl-l-alanyl--d-glutamyl-(l)-meso-diaminopimelyl-(l)-glycine], FK565 [heptanoyl--d-glutamyl-(l)-meso-diaminopimelyl-(d)-alanine] and the immunosuppressive agent cyclosporin A did not alter the release of IL-6 in the same experimental system.  相似文献   
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