In a comprehensive experimental study, the influence of changes in extraand intracellular pH on the mechanical and electrical activity of frog heart ventricle preparations has been investigated. The twitch tension and potassium contracture tension were decreased in acid solutions, provided that the concentration of calcium or the frequency of stimulation was low. In solutions with a high calciu...

While there is abundant literature on the antagonistic interaction between potassium (K) and magnesium (Mg) during root uptake transport, is, however, little published data these nutrients within tissue, especially for sugarcane plants having high demand K Mg. This study aimed to investigate effects of interactions Plants were grown in nutrient solution with increasing application doses at low ...

Ouabain binding by the human erythrocyte membrane is reversible, exhibits a high degree of chemical specificity, and can be detected at ouabain concentrations as low as 1 x 10(-10)M. The relation between ouabain binding and ouabain concentration can be described by a rectangular hyperbola permitting determination of the maximal binding (B(max)) and the ouabain concentration at which ouabain bin...

antimony is a toxic heavy metal for plants, animals and human being. considering its effects on plants growth, different concentrations on watermelon growth and development were studied. the experiment was established on a factorial experiment based on a completely randomized design with 3 replications. the seedlings were grown hydroponically in nutrient solution containing sb-edta (0, 0.25, 0....

background and objectives: one of the most important limiting factors of crop growth in the arid and semi-arid regions, is water deficit stress. mycorrhizal fungi are one of the most important microorganisms in the rhizosphere. the effects of these fungi apply via changes on some of the characteristics of roots and nutrient uptake in host plants in drought conditions. however, symbiotic mycorrh...