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101.
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We investigated the interaction of diclofenac sodium (Dic.Na) with bovine serum albumin (BSA) in the absence and presence of urea using different spectroscopic techniques. A fluorescence quenching study revealed that the Stern–Volmer quenching constant decreases in the presence of urea, decreasing further at higher urea concentrations. The binding constant and number of binding sites were also evaluated for the BSA–Dic.Na interaction system in the absence and presence of urea using a modified Stern–Volmer equation. The binding constant is greater at high urea concentrations, as shown by the fluorescence results. In addition, for the BSA–Dic.Na interaction system, a static quenching mechanism was observed, which was further confirmed using time‐resolved fluorescence spectroscopy. UV–vis spectroscopy provided information about the formation of a complex between BSA and Dic.Na. Circular dichroism was carried out to explain the conformational changes in BSA induced by Dic.Na in the absence and presence of urea. The presence of urea reduced the α‐helical content of BSA as the Dic.Na concentration varied. The distance r between the donor (BSA) and acceptor (Dic.Na) was also obtained in the absence and presence of urea, using fluorescence resonance energy transfer. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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Chand  P. K.  Rech  E. L.  Golds  T. J.  Power  J. B.  Davey  M. R. 《Plant cell reports》1989,8(2):86-89
Summary Freshly isolated cell suspension protoplasts ofSolanum dulcamara were mixed withAgrobacterium rhizogenes, allowed to settle for 2 h, exposed to electrical pulses and further incubated for 2h. Two pulses of 600 V cm–1 for 2 msec separated by 15 sec produced transformed colonies at relative and absolute transformation frequencies which were 3–4 and 10 fold greater than those obtained by co-cultivation of 3 days old protoplast-derived cells with bacteria. Transformed colonies were not produced when freshly isolated protoplasts were mixed withAgrobacterium but not electroporated. Biochemical analysis confirmed the transgenic nature of plants regenerated from protoplast-derived tissues.Abbreviations MS Murashige and Skoog (1962) - NPTII Neomycin phosphotransferase II - SDS Sodium dodecylsulphate  相似文献   
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Summary The relative efficiency of seven extractants for estimating available Cu in sierozem soils of Haryana was studied. Bulk samples of 15 soils ranging in neutral normal amm. acetate extractable Cu from 0.12 to 0.20 ppm were subjected to screen-house study. The quantities of Cu extracted with neutral normal amm. acetate, Morgan’s reagent (pH 4.8)N ammonium acetate (pH 4.8), 0.1N HCl, 0.02M EDTA, critrate-EDTA and DTPA from soils were examined for their correlation with responses of maize in terms of Bray’s percentage yield and percentage Cu uptake. The highest coefficient of correlation was obtained between Cu extractable with neutral 1N NH4OAc and Bray’s per cent yield and per cent Cu uptake. All other methods showed lower values of correlation. The critical level of available Cu estimated with use of neutral normal NH4OAc was 0.16 ppm. Below this value, responses to applied Cu can be expected.  相似文献   
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Abstract

Stable reagents were made from nucleoside-phospho-rochloridites and polymeric sec. amines. Treatment of these with tetrazole/CH3CN and transfer of the resulting solution to immobilized oligonucleotide gave 95% chain elongation.  相似文献   
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A protocol for induction and establishment of Agrobacterium rhizogenes-mediated hairy root cultures of Picrorhiza kurroa was developed through optimization of the explant type and the most suitable bacterial strain. The infection of leaf explants with the LBA9402 strain resulted in the emergence of hairy roots at 66.7% relative transformation frequency. Nine independent, opine and TL-positive hairy root clones were studied for their growth and specific glycoside (i.e., kutkoside and picroside I) productivities at different growth phases. Biosynthetic potentials for the commercially desirable active constituents have been expressed by all the tested hairy root clones, although distinct inter-clonal variations could be noted in terms of their quantity. The yield potentials of the 14-P clone, both in terms of biomass as well as individual glycoside contents (i.e., kutkoside and picroside I), superseded that of all other hairy root clones along with the non-transformed, in vitro-grown control roots of P. kurroa. The present communication reports the first successful establishment, maintenance, growth and selection of superior hairy root clone of Picrorhiza kurroa with desired phyto-molecule production potential, which can serve as an effective substitute to its roots and thereby prevent the indiscriminate up-rooting and exploitation of this commercially important, endangered medicinal plant species. CIMAP Publication No.: 2007-28J  相似文献   
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