This study aimed to investigate the toxic effects of atrazine herbicide on the fry of Caspian Kutum (Rutilus frisii kutum, Kamensky, 1901). First the 96-h LC50 of the fry were exposed to atrazine at the concentration of 24.95 ppm was determined. Then the toxicity of this herbicide on Caspian kutum fry exposed to the concentration of 12.47ppm (1/2 LC50), for four days was measured and compared w...

Three saponins were extracted and isolated from starfish by reversed-phase high performance liquid chromatography (HPLC), and analyzed by fast atom bombardment mass spectrometry (FAB-MS). Their molecular weight information could be obtained by the presence of abundant [M+Na]+ ions and weak [M+H]+ ions in FAB-MS spectra. Moreover, high resolution mass measurements of their [M+Na]+ ions were perf...

Single water fibers of the frog glossopharyngeal nerve respond to relatively high concentrations of NaCl ( > 80 mM). NiCl2 at 1 mM enhanced the Na+ response and reduced the threshold concentration for NaCl to 20 mM. CaCl2 at 0.5-1 mM induced an inhibition of the Ni2+ -enhanced response to Na+ ions. A quantitative explanations for these results is provided by the hypothesis that Ni2+ ions second...

Steady state effluxes of potassium and sodium ions were measured on Pisum sativum var. Alaska root segments excised from seedlings which had grown in a nutrient solution containing the major inorganic ions and either (86)Rb as a tracer for K or (22)Na as a tracer for Na. Fluxes appeared to be from 2 cellular compartments, a small compartment with a high flux rate and a larger compartment with a...

Water shortage is severe in the North China Plain (NCP). In addition to a deficiency of water resources, deterioration of groundwater quality should be of great concern. In this study, hydrogeological analysis was conducted in combination with principal component analysis, correlation analysis and the co-kriging method to identify factors controlling the content of major ions and total dissolve...

background : the present paper aims to study the effect of human and urban activities on the quality of groundwater within the city of khoy in terms of heavy metals, chemical salts, and minerals from the geological formations of this region. methods : samples were provided from 32 pumping wells and the concentration of heavy metals ( cd, cu, mn, pb, zn, fe, as, and b), the main ions (hco 3 ,so ...

It has been proposed that sodium ions of the muscle cells are present ii'' their outer regions and the major portion of an outward movement of sodium ions across the membrane of the striated muscles is accounted for an active transport which is dependent on sodium pump activity sensitive to cardiac glycosides (Mullins and Frumento, 1963 ; Csaky, 1965 ; Horowicz and Gerber ). A previous paper by...

Following a recent demonstration that H,K-ATPase can active transport Na+ at a low rate (Polvani, C., Sachs, G., and Blostein, R. (1989) J. Biol. Chem. 264, 17854-17859), we have looked for and found effects of Na+ ions on the conformational state of gastric H,K-ATPase labeled with fluorescein isothiocyanate. Na+ ions reverse the K(+)-induced quench of the fluorescein fluorescence and somewhat ...

in this research, the groundwater quality of hoz–e–soltan lake and its catchment was studied for drinking, domestic and irrigation uses according to different parameters. this lake with 195 km2 catchment area is located 85 km of southwest of tehran–qom highway. in order to investigate groundwater quality characteristics in the study area, 34 data from water of well belong to 2008 selected to pr...

The first step in the formation of lacrimal gland fluid is believed to depend on transport systems which couple a flux of Cl- ions to the passive influx of Na+ ions across the acinar cell basal-lateral plasma membrane. The transport systems which mediate these fluxes have not yet been characterized, but a review of previous studies (Parod and Putney, Am J Physiol 239:G106, 1980) raises the poss...