X-ray microanalysis of freeze-dried labial gland cryosections revealed that Na concentration was doubled and the Ca/S concentration ratio was decreased in secretory granules of labial glands from patients with cystic fibrosis (CF) when compared with glands from normal subjects. Other results suggested that the decrease in the Ca/S concentration ratio resulted from an increase in S concentration...

In microinjected Myxicola giant axons with elevated [Na]i, Na efflux was sensitive to Cao under some conditions. In Li seawater, sensitivity to Cao was high whereas in Na seawater, sensitivity to Cao was observed only upon elevation of [Ca]o above the normal value. In choline seawater, the sensitivity of Na efflux to Cao was less than that observed in Li seawater whereas Mg seawater failed to s...

Remarkably dynamic Ca z ÷ fluxes control Ca 2 ÷ homeostasis in the outer segments of vertebrate rod photoreceptors (ROS). Ca 2 ÷ fluxes are believed to be carried by only two different membrane proteins embedded in the ROS plasma membrane; these two proteins as well as some of the other main molecular components of ROS are schematically depicted in Fig. 1. ROS are the sites of the process of vi...

Little is known about the role of mitogen-activated protein kinase 6 (MPK6) in Na(+) toxicity and inhibition of root growth in Arabidopsis under NaCl stress. In this study, we found that root elongation in seedlings of the loss-of-function mutants mpk6-2 and mpk6-3 was less sensitive to NaCl or Na-glutamate, but not to KCl or mannitol, as compared with that of wild-type (WT) seedlings. The less...

Preservation of water quality, particularly in areas with inadequate water resources is considered as one of the principles of planning in integrated water management. In Kuhdasht, a region at the west of Iran, groundwater and spring water resources are the major contributors of drinking and irrigation water supply. The aim of this study was to determine the suitability and mapping of springs a...

The interaction between eriochrome black T and Li , Na , K ,Mg and Ca ions in acetone and dimethylsulphoxide solutions has been investigated spectrophotometrically. The formation constants of the resulting 1 : 1 complexes were determined and found to decrease in the order Mg >Ca >Li >K >Na in both solvents used. There is an inverse relationship between the stabilities of the complexes...

The data obtained from field and geothermometric studies and also the REE composition of fluorites associated with lead mineralization at the Kamar-Mehdi mine are compatible with a structurally controlled, fissure filling, epigenetic, hydrothermal origin. Homogenization and last ice melting temperatures for primary fluid inclusions trapped in fluorite crystals indicate that the mineralizati...

salt stress is one of the most chalanging abiotic stresses affecting natural productivity and causing significant croplosses worldwide. a greenhouse experiment was conducted to evaluate the response of two alfalfa cultivars (bamiand hamedani) to 6 levels of salinity (0 as control, 25, 50, 75, 100, 125 mm nacl) at the college of agriculture,shiraz university, shiraz, iran in 2008. plant dry weig...