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981.
Gupta Manish Kumar Chiranjivi Adarsh Kumar Dutta Tanmay Dubey Vikash Kumar Rangan Latha 《Biometals》2022,35(2):285-301
BioMetals - This study reports the synthesis and characterization of zinc derivatized 3,5-dihydroxy 4′, 7- dimethoxyflavone (DHDM-Zn) compound for the development of new antileishmanial... 相似文献
982.
Kumar Krishan Banerjee Dixit Aparna Tripathi Manjari Dubey Vivek Siraj Fouzia Sharma Mehar Chand Lalwani Sanjeev Chandra P Sarat Banerjee Jyotirmoy 《Functional & integrative genomics》2022,22(5):905-917
Functional & Integrative Genomics - Low-grade dysembryoplastic neuroepithelial tumors (DNTs) are a frequent cause of drug-refractory epilepsy. Molecular mechanisms underlying seizure generation... 相似文献
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Poly(catechol) was prepared by using peroxidase as a catalyst in two types of solvent systems: an aqueous dioxane solution and a reverse micellar solution. Peroxidases derived from two sources, horseradish (HRP) and soybean (SBP), were employed as catalyst. The structure of the prepared polymer was elucidated by infrared analysis. Enzymatically prepared film of poly(catechol) at a Pt electrode was subjected to cyclic voltammetric studies in aqueous HCl medium and phosphate buffer pH 6.5. Thermal studies of the polymer were performed by thermogravimetric analysis. The iodine-labelled polymers showed low electrical conductivity in the range of 10−6 to 10−9 S cm−1. The magnetic susceptibility and surface morphological property of the polymer were also studied. 相似文献
987.
L. C. Rai M. Raizada N. Mallick Yashmin Husaini A. K. Singh S. K. Dubey 《Biometals》1990,2(4):229-234
Summary This study presents the effects of Cr, Pb, Ni and Ag on growth, pigments, protein, DNA, RNA, heterocyst frequency, uptake of NH4
+ and N03
–, loss of electrolytes (Na+ and K+), nitrate reductase and glutamine synthetase activities ofNostoc muscorum. The statistical tests revealed a direct positive correlation between the metal concentration and inhibition of different processes. Ni was found to be more toxic against growth, pigments and heterocyst differentiation compared to the other metals. Inhibition of pigment showed the following trend: chlorophyll > phycocyanin > carotenoid. No generalized trend for inhibition of macromolecules was observed. The loss of K+ and Na+ as affected by Cr, Ni and Pb was similar but more pronounced for K+ than Na+. The inhibition of physiological variables depicted the following trend: Na+ loss > K+ loss > glutamine synthetase > NH4 uptake > growth > N03
– uptake > nitrate reductase > heterocyst frequency. This study therefore suggests that loss of electrolytes can be used as a first signal of metal toxicity in cyanobacteria. However, further study is needed to confirm whether the abnormality induced by nickel (branch formation) is a physiological or genetic phenomenon. 相似文献
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In this study, an analytical method is introduced for the identification of predator-prey populations time-dependent evolution in a Lotka-Volterra predator-prey model which takes into account the concept of accelerated-predator-satiety.Oppositely to most of the predator-prey problem models, the actual model does not suppose that the predation is strictly proportional to the prey density. In reference to some recent experimental results and particularly to the conclusions of May (1973) about predators which are ‘never not hungry’, an accelerated satiety function is matched with the initial conventional equations. Solutions are plotted and compared to some relevant ones. The obtained trends are in good agreement with many standard Lotka-Volterra solutions except for the asymptotic behaviour. 相似文献
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