The flux ratio (influx/efflux) of K(+) across the plasmalemma of beet cells at an external potassium concentration of 0.6 mm does not respond to changes of membrane potential in the manner expected for the free diffusion of ions. The K(+) efflux is affected by the presence of adsorbed Ca(2+), but is apparently unrelated to the electrical potential or to the net uptake of potassium. The K(+) eff...

potassium (k) is an essential element for plant growth and development and its importance in agriculture is well known. it plays an important role in improving the quality of agricultural products. besides, micaceous minerals are abundant in iranian soils. the role of plant species in potassium uptake from minerals is significant; but not well investigated. therefore, the objective of this rese...

To determine whether adding blood to a cardioplegic solution affects myocardial preservation, a randomized prospective study was carried out in 60 patients undergoing coronary revascularization to compare the effects of crystalloid potassium cardioplegics (group C) and potassium cardioplegic solutions to which blood has been added (group B) on markers of myocardial metabolism (lactate, inorgani...

This study was conducted to determine the effects of Artemisia sieberi extract (0.2%, 0.4%, and control) on germination, some morphological characteristics, photosynthesis pigments, and nutrients uptake of Peganum harmala. Results showed that the extract of A. sieberi had a significant effect on seed germination and morphological characteristics of P. harmala. The highest seed germination was c...

Nutritional management is an important factor in the success of crop production. In order to evaluate different level of nitrogen, potassium and zinc fertilizers on agro physiological characteristics of green bean a field experiment was conducted as split-plot based randomized complete block design in three replications, in Varamin university field research during 2011. The main plot included u...

Studies have shown that glucose is able to decrease the pH of the surface epithelium jejunal preparations when added in vitro and the existence of a high concentration of protons in the immediate area of the mucosa could be of considerable significance for absorption of electrolytes. The aim of this study is to assess whether the change in pH of Tyrode (solution used for perfusion of the jejunu...

Thrombin causes a dose-dependent depolarization of the transmembrane potential of normal human platelets which can be continuously measured by the fluorescent probe, 3,3'-dipropylthiodicarbocyanine, whose distribution across the plasma membrane has been shown to be dependent upon the membrane potential. The dose-dependent depolarization of the platelet's negative membrane potential by thrombin ...

The phosphoglycerate transport system was employed to supply energy-depleted, lysozyme-treated Salmonella typhimurium cells with a continuous intracellular source of phosphoenolpyruvate. When the cells had been induced to high levels of the phosphoglycerate transport system, a low extracellular concentration of phosphoenolpyruvate (0.1 mM) half maximally stimulated uptake of methyl alpha-glucos...

Rats fed a diet high in potassium for several days survive an acute load of potassium that is lethal to animals on a regular diet. Previous data suggested that this survival occurred because of enhanced kaluresis. Although increased urinary excretion may occur, the major mechanism of this potassium adaptation phenomenon has been found to be extrarenal. Despite nephrectomy just before study, rat...