A combination of the methods described by Schultz et al. (6) and by Ussing and Zerahn (9) was used to measure directly the unidirectional uptake of sodium from the outside solution into the frog skin, under short-circuit conditions. The sodium uptake was determined at six sodium concentrations ranging from 3.4 to 114 mM. NaCl was replaced by choline chloride in the solutions bathing both sides ...

 Increasing quality and vase life of cut flowers play vital role in flower production industry. . Lisianthus (Eustoma grandiflora cv. Echo) has short vase life and it has been revealed that ethylene directly affect the initiation and process of senescence of petals. In this study, the effects of Silver and silicon nanoparticles with four concentrations of 0, 10, 20 and 40 mg L-1 with 4% sucrose...

background: it has been suggested that organophosphates may inhibit gamma-aminobutyric acid (gaba) metabolism in synaptosomal preparations. in the present investigation, we have assessed the interaction between paraoxon and the gaba system at synaptic level.   methods: synaptosomes were prepared from male wistar rats (200-250 g). cerebral cortex was dissected and homogenized, then centrifuged a...

Cesium uptake by sodium-loaded frog sartorius muscles was inhibited 100% by 10(-6)M ouabain and 10(-6)M cymarin. The doses for 50% inhibition of cesium uptake by five cardiotonic aglycones were 1.5 x 10(-6)M for strophanthidin, 2 x 10(-7)M for telocinobufagin, 1.6 x 10(-6) for digitoxigenin, 2.4 x 10(-6)M for periplogenin, and 6.3 x 10(-6)M for uzarigenin. Because of the limited solubility of s...

Background: It has been suggested that organophosphates may inhibit gamma-aminobutyric acid (GABA) metabolism in synaptosomal preparations. In the present investigation, we have assessed the interaction between paraoxon and the GABA system at synaptic level. Methods: Synaptosomes were prepared from male Wistar rats (200-250 g). Cerebral cortex was dissected and homogenized, then centrifuged at ...

Highly toxic arsenate occurs naturally in some well water as well as in industrial wastewaters. Removal of arsenate (As(V)) by biosorption with acid-washed crab shells (AWCS) is very sensitive to solution pH. It greatly increased when the solution pH was lowered from 3.44+/-0.07 to 2.51+/-0.02, but it was reduced at pH below 1.99+/-0.01. Change of solution pH not only affected the charged funct...

Mechanisms of uptake of rare earth elements (REEs) were investigated, particularly those by REE accumulator species (autumn fern). Rare earth elements are practically insoluble under natural conditions, suggesting some unknown mechanism in REE accumulator species. In the present investigation, two notable phenomena were observed. (I) Concerning the ionic-radius dependence of REE uptake by leave...