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AIM: To compare the efficacy of the coadministration of ranitidine bismuth citrate plus the antibiotic clarithromycin, with ranitidine bismuth citrate alone or clarithromycin alone for the healing of duodenal ulcers, eradication of H. pylori and the reduction of ulcer recurrence. METHODS: This two-phase, randomized, double-blind, placebo- controlled, multicentre study consisted of a 4-week treatment phase followed by a 24-week post-treatment observation phase. Patients with an active duodenal ulcer were treated with either ranitidine bismuth citrate 400 mg b.d. for 4 weeks plus clarithromycin 500 mg t.d.s. for the first 2 weeks; ranitidine bismuth citrate 400 mg b.d. for 4 weeks plus placebo t.d.s. for first 2 weeks; placebo b.d. for 4 weeks plus clarithromycin 500 mg t.d.s. for the first 2 weeks; or placebo b.d. for 4 weeks plus placebo t.d.s. for the first 2 weeks. RESULTS: Ulcer healing rates after 4 weeks of treatment were highest with ranitidine bismuth citrate plus clarithromycin (82%) followed by ranitidine bismuth citrate alone (74%; P = 0.373), clarithromycin alone (73%; P = 0.33) and placebo (52%; P = 0.007). Ranitidine bismuth citrate plus clarithromycin provided significantly better ulcer symptom relief compared with clarithromycin alone or placebo (P < 0.05). The coadministration of ranitidine bismuth citrate plus clarithromycin resulted in significantly higher H. pylori eradication rates 4 weeks post-treatment (82%) than did treatment with either ranitidine bismuth citrate alone (0%; P < 0.001), clarithromycin alone (36%; P = 0.008) or placebo (0%; P < 0.001). Ulcer recurrence rates 24 weeks post-treatment were lower following treatment with ranitidine bismuth citrate plus clarithromycin (21%) compared with ranitidine bismuth citrate alone (86%; P < 0.001), clarithromycin alone (40%; P = 0.062) or placebo (88%; P = 0.006). All treatments were well tolerated. CONCLUSIONS: The coadministration of ranitidine bismuth citrate plus clarithromycin is a simple, well-tolerated and effective treatment for active H. pylori- associated duodenal ulcer disease. This treatment regimen effectively heals duodenal ulcers, provides effective symptom relief, eradicates H. pylori infection and reduces the rate of ulcer recurrence. The eradication of H. pylori infection in patients with recently healed duodenal ulcers is associated with a significant reduction in the rate of ulcer recurrence.  相似文献   
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Autologous blood (collected preoperatively or salvaged intraoperatively) is the safest blood available for transfusion, but its use is not always feasible. It may be possible to decrease a patient's exposure to homologous donors. Pediatric cardiac surgery patients frequently are unable to donate autologous blood preoperatively. Since 1984, attempts have been made to provide parental apheresis platelets and intraoperative blood salvage to such patients to decrease their donor exposure. Further decreases in donor exposure have been the object of a program of collecting from one committed donor all the blood a patient is anticipated to need. This article reviews the experience with 50 pediatric cardiac surgery patients on such a program, in whom the mean decrease in homologous-donor exposure was 57 percent (range, 12-93%). Thirteen of these patients received only homologous blood products from one committed donor, for a mean decrease in homologous-donor exposure of 80 percent (range, 50-93%). A comparison of 12 of these 13 recipients with a matched control group showed no significant difference in red cell transfusion practice but a significant difference in the number of homologous-donor exposures per m2 of body surface area (BSA) (mean donor exposures/m2 of BSA: patients = 1.5, controls = 10.5). The use of one committed donor and autologous blood can provide a minimal-exposure transfusion.  相似文献   
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Radiation oncology registrar training varies between centres, reflecting to some extent the varied training experiences of specialists. The attempts of one department to formalize the philosophy, aims and structure of its training are described and illustrated.  相似文献   
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Urea kinetics were measured on 11 occasions in six normal, breast-fed infants aged 29-88 days. Prime and intermittent oral doses of [15N,15N]urea with measurement of enrichment of urea in urine were used. The rate at which urea appeared in the urea pool was 265 mg N/kg per hour, 85% of which derived from endogenous production and 15% from the diet. Urinary excretion of urea was 87 mg N/kg per hour. Therefore, 60% of the urea entering the pool each day was hydrolysed by the metabolic activity of the colonic microflora and the nitrogen was made available for further metabolic interaction. The rate of urea appearance and the extent to which urea nitrogen was salvaged were greater in infants under 6 weeks than in those over 6 weeks, indicating that urea kinetics is a more active process at an early age, and slows with time. With respect to factors influencing urea kinetics, the apparently conflicting results which have appeared in the literature may be explained. The results may help explain the growth of breast-fed infants on low protein intakes.  相似文献   
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