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G Kitis

Publications and source records attributed to G Kitis.

27 records · Page 2Linked to original sources

The influence of regenerated thermoluminescence on low-dose dosimetry.

The contribution of regenerated thermoluminescence to low doses is studied for the case of CaF2-Dy (TLD-200). A component of 2 mrad was found for pre-irradiation doses of 70 rad, 1 krad and for 10 days' regenerating time. The results are discussed and the conclusion is that for measurements of extremely low dose it is better to use virgin crystals.

Calcium Fluoride↗

Altered jejunal surface pH in coeliac disease: its effect on propranolol and folic acid absorption.

1. Propranolol and folic acid absorption were studied separately in healthy subjects, non-coeliac patients and patients with treated and untreated coeliac disease. 2. The surface pH of jejunal biopsy samples was measured with a pH electrode. 3. When compared with values found in healthy subjects, plasma propranolol levels were elevated in coeliac disease and, in contrast, serum folic acid levels were depressed after oral administration of the drug. Jejunal surface pH was more alkaline in the coeliac groups than in the healthy and non-coeliac subjects. 4. Pharmacokinetic analysis of the plasma drug levels allowed evaluation of the rate constants associated with absorption and elimination. The absorption rate constant was decreased for folic acid in the coeliac group, but increased for propranolol. These changes correlated with variation in surface pH. 5. Although the changes in drug disposition in treated and untreated coeliac disease are the result of several factors, it is suggested that jejunal surface pH may affect the rate of absorption and therefore the plasma concentration-time profile of drugs which undergo dissociation.

Adolescent↗

Association of coeliac disease and inflammatory bowel disease.

The association of coeliac disease and inflammatory bowel disease is rare, as only three individual cases have been reported. Four additional cases of the association are described. A review of the prevalence figures for the two disorders suggests that this is more than a chance association.

Adolescent↗

Finger clubbing in inflammatory bowel disease: its prevalence and pathogenesis.

Finger clubbing, measured objectively by using the hyponychial angle, was present in 75 out of 200 (38%) patients with Crohn's disease, 15 out of 103 (15%) with ulcerative colitis, and two out of 24 (8%) with proctitis. In Crohn's disease and ulcerative colitis the hyponychial angle was significantly correlated with both disease activity and the extent of fibrosis in the resected specimens from 47 surgically treated patients. The prevalence of finger clubbing in patients with macroscopic disease within the area of the gut innervated by the vagus nerve was significantly higher than that in patients in whom the disease was confined to the distal colon and rectum. Finger clubbing in patients with Crohn's disease tended to regress after resection of macroscopic disease. It is concluded that finger clubbing is significantly commoner in Crohn's disease than ulcerative colitis. The focal stimuli for finger clubbing include mucosal inflammatory change and fibrosis mediated by the vagus and possibly other autonomic pathways acting as the afferent arc of a finger-clubbing reflex.

Adolescent↗