The effect on ciprofloxacin's bioavailability (F) of calcium carbonate given 2 h before ciprofloxacin administration in 12 male volunteers was studied. The relative F with calcium was 0.98, maximum concentration of drug in serum increased significantly from 1.98 to 2.42 mg/liter (P = 0.039), and time to maximum concentration of drug in serum decreased from 1.82 to 1.26 h (P = 0.038). Thus, a si...

Articulating spacers should be wear-resistant and load-bearing to avoid prolonged immobilization of the patient and to reduce morbidity. However, due to the articulation of both components, a release of cement wear particles is to be expected. The aim of this study was to investigate the wear performance of a new spacer cement that contains calcium carbonate as a radio-opaque substance, in comp...

1. The possible natriuretic and kaliuretic effects of a single dose of lithium, as used in lithium clearance studies, were investigated in 15 healthy subjects on fixed sodium (100 mmol/24 h) and potassium (70 mmol/24 h) intakes. Lithium carbonate (300 mg or 600 mg) or placebo tablets were administered, double-blind and in random order, midway through a 48 h urine collection (divided into six 8 ...

The involvement of elements in the pathological process of primary hypertension has been established. The serum levels of copper, iron, zinc, sodium, potassium and calcium were studied by atomic absorption spectrophotometery and flame photometry in hypertensive and normal subjects. Serum copper and zinc levels were increased in hypertensive patients (25.5% and 14.7% respectively) as compar...

Intact human erythrocytes can be readily loaded with calcium by incubation in hypersomotic media at alkaline pH. Erythrocyte calcium content increases from 15-20 to 120-150 nmol/g hemoglobin after incubation for 2 h at 20 degree C in a 400 mosmol/kg, pH 7.8 solution containing 100 mM sodium chloride, 90 mM tetramethylammonium chloride, 1 mM potassium chloride, and 10 mM calcium chloride. Calciu...

Pliocene and Pleistocene sediments from Sulu Sea ODP Sites 768 and 769 contain high-resolution records of pelagic sedimentation in a deep marine silled basin. Carbonate analyses reveal that both sites are free of pelagic carbonate up until 2.4 Ma, at which time carbonate becomes a major component of the pelagic marl sedimentation. The timing of this increase in calcium carbonate accumulation is...

Crustaceans, like most mineralized invertebrates, adopted calcium carbonate mineralization for bulk skeleton reinforcement. Here, we show that a major part of the crustacean class Malacostraca (which includes lobsters, crayfishes, prawns and shrimps) shifted toward the formation of calcium phosphate as the main mineral at specified locations of the mandibular teeth. In these structures, calcium...