T he issue of calcium (Ca) availability in alkaline, mineral soils has long been a matter of contention. Based on the commonly used ‘exchangeable cations’ test (ammonium acetate extraction), most Western soils are well supplied with Ca. However, in alkaline soils, a substantial percentage of ‘exchangeable’ calcium identified by this test can be in chemical forms not readily available to plants ...

Interaction of alkaline earth metal (magnesium, calcium, strontium and barium) ions with acetic and lactic acid in aqueous media was investigated by C NMR spectroscopy. In the acetate systems, signals whose chemical shifts were the averages of those of the free and bound acetate ions were observed. Downfield shifts of the carboxylate carbon signals with increasing metal ion concentration indica...

Dissolution rates and apparent solubilities for synthetic hydroxyapatite in acetate buffers containing phosphate and strontium ions in the range of 10-3 to 10-2 M were determined under various pH and buffer conditions. Critical examination of the role of strontium with a physical model suggests that a calcium-strontium apatite surface complex may govern the driving force of the dissolution reac...

Tartrate-resistant acid phosphatase activity may be demonstrated in paraffin-embedded liver and spleen specimens as well as in decalcified bone marrow biopsies after fixation in a mixed glutaraldehyde-formaldehyde-calcium acetate solution. This technique may routinely be applied to haematologically relevant material and aids in the differential diagnosis of hairy-cell leukaemia.

AIMS To study the electro-activation of potassium acetate, potassium citrate and calcium lactate aqueous solutions and to evaluate their antimicrobial effect against E. coli O157:H7 at ambient temperature. METHODS AND RESULTS Potassium acetate, potassium citrate and calcium lactate aqueous solutions were electrically excited in the anodic compartment of a four sectional electro-activation rea...

Guinea pig sperm were suspended in calcium-containing medium supplemented with various concentrations of the tetrasaccharide, stachyose. At concentrations up to and including 0.6 M, stachyose was without effect on the A23187-induced acrosome reaction. At 1.0 M stachyose, greater than 97% of sperm retained their acrosome after exposure to A23187, as judged by light microscopy. Electron microscop...

We determined the effect of conjugated equine estrogen plus medroxyprogesterone acetate on calcium content of aortic atherosclerotic lesions in oophorectomized adult New Zealand rabbits submitted to a cholesterol rich diet. Five groups of 10 animals each were studied: G1 = control, G2 = cholesterol diet only, G3 = diet plus conjugated equine estrogen (0.625 mg/day); G4 and G5 = diet, conjugated...

To facilitate the study of skin tumor promotion, a cell culture model system with characteristics analogous to initiated mouse epidermis was established. Cells of the keratinocyte cell line 308, derived from adult mouse skin initiated with 7,12-dimethylbenz[a]anthracene, display the initiated phenotype, since papillomas are produced when the cells are grafted to the backs of athymic mice. Cocul...

A 63-year-old man with history of acquired immune deficiency syndrome (AIDS), intravenous drug use, and recent anaphylaxis complicated by acute kidney injury presented with nausea, vomiting, constipation, rectal bleeding, and abdominal pain for 3 days. Laboratory findings included a CD4 count of 104/mm3, anemia with hemoglobin of 10.9g/dL andhematocrit of 31.7%, elevated blood urea nitrogen (42...