Hypertensive patients were treated with either chlorthalidone or frusemide for periods of two to four months. Reduction in blood pressure was seen with chlorthalidone but not with frusemide. This hypotensive effect appeared to be independent of the natriuretic effect. A significant reduction in total exchangeable potassium (KE) was seen with both agents, but no patient showed adverse symptoms o...

-A laboratory study of the hydraulic conductivity (HC) of a marine clay with monovalent, divalent and trivalent cations revealed large differences in HC. The exchangeable cations employed in this study are Na, K, NH4, Mg, Ca and AI in order of increasing valency. An interpretation of the results derived from consolidation tests suggests that HC is significantly affected by the valency and size ...

The in ̄uence of soil exchangeable cations and aluminium content on the distribution of various terrestrial gastropods was investigated. Calcium was the most important factor, though aluminium and magnesium content also had some effect. Potassium and sodium had no signi®cant in ̄uence on distribution. The species most sensitive to the factors analysed were Cochlicopa lubrica, Vertigo pygmaea and ...

~Clay materials separated from estuarine sediments in Louisiana exhibit a selectivity for exchangeable calcium in laboratory experiments. The studies were conducted at 25~ and 60~ in mixed calcium and potassium chloride solutions in which the equivalent fraction of potassium varied from 0.12 to 0.54. Calcium selectivity was observed to increase with an increase in the equivalent fraction of pot...

introduction: intensified agriculture over a long-term is an important factor in soil change phenomena that can cause some unwanted effects on soil properties. to examine this hypothesis, chemical properties of the soils under sunflower cultivation over five decades and adjoining virgin lands were investigated in order to monitor changes caused by long-term cropping. the studied soils are influ...

ABSTRACT-The influence of intensive crop rotation on the distribution of potassium forms and clay mineralogy was assessed under a Mediterranean condition in the Piranshar region, northwest of Iran. For this purpose, surface soil samples in relation to six soil sub-groups from crop rotationfiled (sugar beet, wheat, pea, and barley) over five decades and the adjacent uncultivated lands were descr...

A multi-syringe flow injection system for the potentiometric determination of exchangeable potassium in soil samples is proposed. Firstly, a manifold was devised to allow determination in soil extracts prepared off-line. It was possible to analyze samples prepared in extractants with different composition (Mehlich or Morgan) without physical or chemical modification of the manifold. A linear dy...

Polymyxin B, an amphiphilic, cationic peptidolipid, which is thought to bind to anionic phospholipids in cell membranes, is shown to interact with the cellular calcium of cultured neonatal rat myocardial cells in a dose-dependent, partially reversible manner. At concentrations of less than or equal to 0.1 mM, it has two distinct effects. First, it results in displacement of 1.4 +/- 0.3 mmol Ca/...