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Collagenous colitis is characterized by the presence of a thick subepithelial collagen band in the colonic mucosa. The condition was diagnosed on rectal biopsy in 10 patients (one male, nine females) who presented with watery diarrhoea. Although rectal mucosal erythema was present in three and ulceration in two, the mucosa was of normal endoscopic appearance in five of the patients. There was marked variability in the thickness of the submucosal collagen band, both between and within individuals. Empirical drug therapy included sulphasalazine, glucocorticoids and antidiarrhoeals. All patients reported symptomatic improvement.  相似文献   
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BACKGROUND: Both cryosurgery, with and without prior curettage, and surgical excision (SE) are common therapeutic strategies for basal cell carcinoma (BCC). OBJECTIVE: The objective was to compare the efficacy between curettage plus cryosurgery (C&C) and SE in nonaggressive BCC of the head and neck. MATERIALS AND METHODS: A randomized controlled trial was carried out, in which tumors were assigned to either C&C (n=51) or SE (n=49). C&C was performed with a double freeze-thaw cycle after prior curettage of the tumor. SE was performed with a margin of 3 mm and with delayed histologic examination. RESULTS: Recurrences occurred 9 times after C&C (17.6%) and 4 times after SE (8.2%). The overall 5-year recurrence probability was 19.6% for C&C and 8.4% for SE (p=.10). A hazard ratio of 2.57 (95% CI, 0.79-8.34) indicated a putative, but not statistically significant, advantage of SE. CONCLUSION: These data reflect the outcome of the first randomized controlled trial with long-term follow-up in the treatment of BCC, comparing C&C with SE. Although not statistically significantly different, the observed differences could still be of clinical relevance. Owing to the trend toward lower recurrence rates, better cosmetic results, and reduced wound healing time, we believe that SE should be preferred to C&C in the treatment of primary, nonaggressive BCC of the head and neck.  相似文献   
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Preventing accidental injury to young children in the home using volunteers   总被引:1,自引:0,他引:1  
Accidental injury in the home is a major cause of death andill-health among young children. Reducing home safety hazardsby the use of safety devices such as stair barriers and safetytaps has the potential to prevent home injuries. Little is knownabout levels of home safety hazards or how to encourage parentsto reduce hazards. The Safe Place Project examined parents'knowledge of home safety and the prevalence of safety hazardsin homes where there were young children. The study also evaluatedthe effectiveness of a low-cost strategy aimed at reducing homesafety hazards. The strategy used trained volunteers to providehome safety checks and tailored safety education in conjunctionwith increasing the availability of home safety devices. Onehundred and six families with young children participated inthe project. Some homes contained many hazards, with 43% ofthe sample having more than 10 home safety hazards. At follow-up,the intervention group showed a significant reduction in homehazards and a trend towards an increase in knowledge of homesafety.  相似文献   
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BACKGROUND: CD40 has a role in the regulation of immune responses, cell proliferation and migration, and apoptosis. Little is known of its distribution in oral mucosal pathology. METHODS: Oral keratinocyte lines were tested for CD40 protein by Western blotting. Immunohistochemistry was used to stain paraffin sections of oral mucosa in health and in inflammatory, reactive, dysplastic and malignant disease. RESULTS: Western blotting confirmed the presence of CD40 in oral keratinocytes. CD40 was generally expressed by keratinocytes in the basal layer, with variable parabasal expression. Langerhans cells also stained positively. Expression was lost in nine of 33 (27%) epithelial dysplasias, seven of which were severe. Eighty-one percent of well, 69% of moderately and 50% of poorly differentiated oral squamous cell carcinomas (OSCC) expressed CD40. Overall, 45 of 65 (69%) OSCC were positive. The pattern of expression was unrelated to tumour differentiation. CONCLUSION: CD40 expression by basal and parabasal oral keratinocytes is physiological. Expression is lost in approximately one-third of oral epithelial dysplasias and OSCC. The significance of such loss remains unknown, but may be related to immunological or other abnormalities of keratinocyte homeostasis.  相似文献   
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Most patients with implantable defibrillators have diminished cardiac function. Progressive heart failure might impair defibrillation efficacy, leading to interpreted device, failure. This study sought to determine the effect of ventricular dysfunction on defibrillation energy using a biphasic endocardial system. Eleven dogs were ventricularly paced at 225 pulses/min for 2 weeks to induce ventricular dysfunction, and five control dogs remained unpaced. Dose response defibrillation probability curves were generated for each animal at baseline, after 2 weeks (at which time the pacemakers were turned off in the paced group), and then 1 week later. The defibrillation thresholds, ED20, ED50, and ED80 (the 20%, 50%, and 80% effective defibrillation energies, respectively) were determined for each dog at each study. In the paced dogs, the mean ejection fraction fell from 55% to 25% after pacing (P < 0.0001), and rose to 46% after its discontinuation (P = 0.0002). The defibrillation threshold, ED20, ED50, and ED80 remained unchanged in both the control and paced groups for all three studies, even after adjustment for dog weight or left ventricular mass. Rapid pacing produced no change in left ventricular mass. It induced ventricular cavity dilatation and wall thinning, which had opposing effects on defibrillation energy requirements, resulting in no net change of the ED50 in heart failure. In conclusion, the defibrillation efficacy of a biphasic transvenous system is not changed by the development of heart failure using the rapid paced canine model.  相似文献   
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Gingival hyperplasia may be genetic, may be acquired as a consequence of exposure to drugs and other agents or may appear as part of a more widespread disorder. Five patients who acquired gingival hyperplasia due to amyloidaceous deposits staining only for fibrin are presented. This appears to be a new entity related to ligneous conjunctivitis.  相似文献   
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The 5-year “Preventing Alcohol Trauma: A Community Trial” project in the United States was designed to reduce alcohol-involved injuries and death in three experimental communities. The project consisted of five mutually reinforcing components: (1) Community Mobilization Component to develop community organization and support, (2) Responsible Beverage Service Component to establish standards for servers and owner/managers of on-premise alcohol outlets to reduce their risk of having intoxicated and/or underage customers in bars and restaurants, (3) Drinking and Driving Component to increase local DWI enforcement efficiency and to increase the actual and perceived risk that drinking drivers would be detected, (4) Underage Drinking Component to reduce retail availability of alcohol to minors, and (5) Alcohol Access Component to use local zoning powers and other municipal controls of outlet number and density to reduce the availability of alcohol. This paper gives an overview of the rationale and causal model, the research design and outline of each intervention component for the entire prevention trial.  相似文献   
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