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17 22 Matsumoto, K., Ohta, T., Tanaka, T. (2005) Dependence of stomatal conductance on leaf chlorophyll concentration and meteorological variables. Agric. For. Meteorol. 132

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Acta Biologica Hungarica
Authors: Farzaneh Garousi, Béla Kovács, and Szilvia Veres

. Mao , H. , Wang , J. , Wang , Z. , Zan , Y. , Lyons , G. , Zou , C. ( 2014 ) Using agronomic biofortification to boost zinc, selenium, and iodine concentrations of food crops grown on the loess plateau in China . J. Soil Sci. Plant Nutr

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. Peanut/maize intercropping induced changes in rhizosphere and nutrient concentrations in shoots. Plant Physiol. Bioch. 45: 350–356. Zhang F. Peanut/maize intercropping induced changes

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Acta Biologica Hungarica
Authors: Imène Ben Salah, Nahida Jelali, T. Slatni, Margaret Gruber, A. Albacete, Cristina Martínez Andújar, V. Martinez, F. Pérez-Alfocea, and C. Abdelly

Serraj, R., Fleurat-Lessard, P., Jaillard, B., Drevon, J. J. (1995) Structural changes in the inner-cortex cells of soybean root nodules are induced by short-term exposure to high salt or oxygen concentrations. Plant Cell Environ. 18 , 455

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AMP-deaminase (EC 3.5.4.6) is an enzyme responsible for stabilising adenylate energy changes. The properties of this enzyme are controlled by various ligands of hydrophobic nature. An investigation of enzyme activity alterations under the influence of natural phenolic acids (tannic, ellagic and gallic) which are soluble in water, could evidence the biological toxicity of these compounds. In our study purified AMP-deaminase isolated from white muscle of Cyprinus carpiowas exposed to phenolic acids in the concentration range of 1 to 50 µM as well as to tannic acid in the presence of Cu2+ions (5 µM). On the basis of the obtained results we can conclude that among the tested acids, gallic acid did not contribute to the change in AMP-deaminase activity, whereas ellagic acid diminished its activity at the highest concentration (50 µM). Tannic acid caused a significant decrease in the enzyme activity in comparison to control for all used concentrations. Cu2+ions alone reduced the activity of AMP-deaminase for all studied concentrations. A combined action of a chosen Cu2+ions concentration (5 µM) with tannic acid at the concentration higher than 2 µM resulted in a decrease in the enzyme activity, but for lower tannic acid concentration of 1 µM the activity of AMP-deaminase was stimulated. These experiments showed that tannic acid may stop free radical chain reactions only at low concentrations (1 µM) in the presence of Cu2+ions (5 µM).

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induced in HeLa cells by low concentrations of paclitaxel (Taxol) results in abnormal mitotic exit and apoptotic cell death. Cancer Res. 56 , 816–825. Wilson L. Mitotic block

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. (2001) Peripheral interleukin-6 administration increases extracellular concentrations of serotonin and the evoked release of serotonin in the rat striatum. Neurochem. Int. 38 , 303-308. Peripheral interleukin-6 administration

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novobiocin, ≥16 mm [ 39 ]. Vancomycin E-test Method The Minimum inhibitory concentration (MIC) of each S. aureus isolate and control strains ( Enterococcus faecalis ATCC 29212 and S. aureus ATCC 29213) to vancomycin

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The effect of increasing NaCl concentrations on biomass, hydrogen peroxide (H2O2), ascorbic acid (ASC), proline and total thiol, and the activity of some antioxidant enzymes in alfalfa (Medicago sativa L. cv. Gara-Yonjeh) were investigated. The dry weights of roots and shoots with increasing NaCl concentrations decreased progressively, and the strongest toxicity was detected at NaCl treatment of 200 mM. Superoxide dismutase (SOD) activity in the leaves increased gradually up to NaCl concentrations of 100, while the higher concentration of NaCl reduced SOD activity in both leaves and roots. The maximum levels of ascorbate peroxidase (APX) activity were increased at 150 mM and 100 mM NaCl in leaves and roots of Gara-Yonjeh, respectively. Peroxidase (POD) activity in roots of Gara-Yonjeh increased (82% at 200 mM) by salinity, while it decreased (43% at 200 mM) in leaves. In contrast, catalase (CAT) activitiy increased (84% at 200 mM) in leaves, and decreased (57% at 200 mM) in the roots of Gara-Yonjeh. Electrophoresis analysis suggested that different patterns in SOD, CAT and POD isoenzymes depend on NaCl concentrations, and the staining intensities of these isoforms are supported the results obtained from the spectrophotometric determinations. In POD and CAT, activity of isoform III was detected at all concentrations, by a “low-high-low” pattern, with the maximum activity at 50 mM of NaCl. Results imply that the function of antioxidant systems in higher NaCl concentration is responsible for the salt tolerance observed in Gara-Yonjeh.

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A study on the effect of water soluble fractions (WSF) of petroleum products (diesel, kerosene and petrol), on two test microalgae — Desmodesmus quadricauda and Eudorina elegans — was conducted in the laboratory for 14 days using various concentrations (0%, 10%, 25%, 50%, 75% and 100%). The growth response was measured spectrophotometrically using optical density at 680 nm. A general assessment indicates that both microalgae used were impaired by the high concentrations of WSF of these fuel oils, while lower concentrations stimulated growth. For Eudorina elegans, maximum growth was obtained at 10% in all fuel oils except kerosene, where maximum growth was obtained at 25%. For Desmodesmus quadricauda, maximum growth was recorded at 10% in diesel, 25% in kerosene and 50% in petrol. The study revealed that both test microalgae had their minimum growth and were highly inhibited in 100% concentration of water soluble fractions of the fuel oils. E. elegans was more inhibited than D. quadricauda in all concentrations of water soluble fractions of the fuel oils except at 100% concentration, where D. quadricauda was more inhibited. Statistically, there was significant difference between the various concentrations of the WSF of most fuel oils investigated except between control and 10% of E. elegans in petrol and between 10 and 25% of both test algae in diesel

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