Five elderly achlorhydric patients and five controls took 250 mg tetracycline as a capsule or as an oral solution. Venous blood samples drawn during the 12-hr period following administration and urine collected for 72 hr post-dosing were assayed fluorometrically for tetracycline. There were no differences between the two groups in either rate or extent of tetracycline absorption. The mean apparent first-order rate constant (ka) for absorption of drug from capsules was 0.58 +/- 0.17 hr-1 for patients and 0.65 +/- 0.21 hr-1 for controls. The mean extent of absorption for capsule dosage forms relative to an oral solution was 1.0 +/- 0.20 for patients and 1.0 +/- 0.24 for controls. Concurrent administration of 2 gm of sodium bicarbonate to 2 of the normal subjects resulted in no impairment of either the rate or extent of tetracycline absorption from capsules, suggesting that the effect of elevated gastric pH on tetracycline bioavailability may relate to formulation.
A frank perforation of the upper gastroin-testinal tract is usually repaired surgically. With the advent of endoscopic clipping devices, patients with gastric [1], duode-nal [2], and colonic [3, 4] perforations have been treated endoscopically. We report the successful use of an endoscopic clipping device to treat a duodenal perforation that occurred during an endo-scopic ultrasound examination.
Velocity sedimentation at unit gravity separated peripheral erythrocytes of adult rainbow trout according to age and size. The cells located at the top of the gradient contained numerous polyribosomes, few mitochondria and an essentially electronlucent nucleus. The cells at the bottom of the gradient no longer contained these cytoplasmic organelles and had an essentially electron-dense nucleus. The middle of the gradient contained cells with either very few polyribosomes or cells devoid of this organelle.The length, width and mean corpuscular volume (MCV) ofthe average cell increased and the width to length ratio decreased progressively from the top of the gradient to the bottom.No statistical significance could be determined in the changes of the mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) although they appeared to follow theoretical projections.The use of haematocrit, red cell count, haemoglobin concentration, MCV, MCH and MCHC in assessing erythropoietic activity and the size and haemoglobin content of the maturing cell is discussed.
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