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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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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   
7.
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   
8.
In order to evaluate the effects of pentoxifylline on sperm motility and longevity, a controlled in-vitro study was conducted on normozoospermic donor semen samples using the Cellsoft automated system for sperm motility analysis. After incubation and selection, pentoxifylline was found to improve the recovery of spermatozoa and to increase their velocity. In the subgroup of progressively motile spermatozoa, curvilinear velocity was also enhanced. It is concluded that pentoxifylline has an effect on the vigour, but not on the pattern, of sperm motion. Pentoxifylline did not improve the motility characteristics of senescent spermatozoa in normozoospermic sperm samples. Sperm survival, as shown by supra-vital staining, and motility longevity both decreased with time after pentoxifylline treatment.  相似文献   
9.
The analogues [Glu(OBzl)11]SP6–11 and [Glu(OBzl)11]SP5–11 of the C-terminal hexapeptide and heptapeptide of Substance P have been synthesized by conventional solution methods. In each analogue the SCH3 group of Met11 is replaced by the COOCH2C6H5 group. The in vitro activity of both analogues has been determined on three biological preparations: guinea pig ileum (GPI), rat vas deferens (RVD), and rat portal vein (RPV). The selectivity for the different receptors has been studied by utilizing atropine-treated guinea pig ileum (GPI + At). The results showed that both analogues are mainly active on GPI through the NK-1 receptor and that both analogues are equipotent to Substance P.  相似文献   
10.
Dialytic ultrafiltration with haemofilter was performed in 16 patients with malignant ascites refractory to treatment with sodium restriction, diuretic and systemic chemotherapy. A continuous flow of ascitic fluid at a rate of 300–400 ml/min through a haemofilter was maintained by a blood pump. The protein-rich ascitic fluid was re-infused into the peritoneal cavity with sodium and water removed. An average of 5.2 1 of filtrate was removed over a mean interval of 3.5 h. Bleomycin (60 mg) was administered intraperitoneally following the procedure. Complete response was observed in six patients (37.25%) and partial response occurred in four (25%). The remaining patients showed no response. Complications of the dialytic ultrafiltration procedure and toxicity of intraperitoneal administration of bleomycin were minimal. The technique of dialytic ultrafiltration is simple, safe and cost-effective and could be used as an adjuvant therapy for intraperitoneal chemotherapy.  相似文献   
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