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891.
Narrowband UV‐B is a safe and efficacious option for the treatment of adult psoriasis. However, the use of this therapy has been limited in children due to its long‐term carcinogenic potential. It has proven to be an adequate alternative in patients whose condition is refractory to topical treatment. Aims To evaluate the efficacy and short‐term safety of narrowband UV‐B in the treatment of paediatric psoriasis, and to compare our results with those obtained in other studies on paediatric psoriasis. Materials and methods Over a period of 2 years and 4 months, we administered narrowband UV‐B to 20 children diagnosed with psoriasis that was refractory to topical therapy. The therapeutic response was measured using the Psoriasis Area and Severity Index (PASI). Results Between August 2005 and December 2007, 20 children received narrowband UV‐B. Their median age was 13 years (range, 5–17 years), and the median initial PASI score was 8.25 (2.7–22.2). A median of 28 (10–59) sessions was required to achieve clearance, reaching almost complete or total remission (median final PASI) in all but two patients. Six patients required a new therapeutic course because of relapse, and the mean duration of remission was 8 months (4–18). No patients experienced severe adverse events during therapy, and only one discontinued treatment, for unrelated reasons. Discussion and conclusion Narrowband UV‐B for the treatment of paediatric psoriasis has received little attention in the literature. This treatment has been limited in children because of its potential long‐term carcinogenic effects, and most information has been extrapolated from adults. Nevertheless, narrowband UV‐B phototherapy is an effective and well‐tolerated therapeutic alternative in paediatric patients with severe psoriasis.  相似文献   
892.
Background During the past decades, there has been a substantial increase in the incidence of cutaneous malignant melanoma (CMM) among all Caucasian populations. Spain presents one of Europe’s lowest incidence and mortality rates. Objective The aim of this study was to analyse the recent trends of CMM incidence and mortality in a region with lower incidence as well as to project their future trends. Methods Cutaneous malignant melanoma incidence data were provided by the Tarragona and Girona population‐based cancer registries and mortality data were provided by the Mortality Registry of Catalonia. Time trends of incidence and mortality rates by CMM were assessed through the estimated annual percentages of change of the incidence and mortality age‐standardized rates to the World Standard Population. Projections were based on a Bayesian age–period–cohort model using second order autoregressive effects on age. Results During the last 20 years CMM incidence has increased substantially at a faster rate than any other neoplasms in Catalonia, particularly among women and this trend will probably continue for the next several years. Nevertheless, CMM mortality trends have been and probably will remain stable during this period. Conclusion Improvements in preventive activities should be implemented to decrease incidence and mortality from this cancer. Monitoring stage‐specific trends in CMM incidence can assess the impact of preventive strategies; for this reason more complete information on diagnostic features of CMM patients in the Spanish population‐based cancer registries are necessary.  相似文献   
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OBJECTIVES: The main aim of this study was to reach consensus between students, faculty and general practice teachers on the educational objectives and requirements of the clerkship in general practice. METHOD: The consensus procedure consisted of four steps and all active general practice teachers (n = 116) were asked to participate in the study. RESULTS: We identified 189 educational objectives: 127 complaints (problems, symptoms, syndromes), 29 clinical skills and 37 objectives concerning the theoretical dimensions of general practice. Educational requirements crystallized to 16 essential preconditions of a teaching practice and 35 didactic activities to be performed by the general practice teachers. CONCLUSIONS: These consensus results will be used to structure the medical curriculum and as guidelines for the educational process during the clerkship.   相似文献   
895.
Surh  YJ; Kim  SG; Park  KK; Sohn  Y; Lee  JM; Kim  ND; Miller  JA 《Carcinogenesis》1998,19(7):1263-1267
2-(Allylthio)pyrazine (2-AP), synthesized for its possible use as a hepatoprotective agent, has been found to selectively inhibit rat hepatic cytochrome P450 2E1 (Kim et al., Biochem. Pharmacol., 53, 261- 269, 1997), while it enhances the activities of phase II detoxification enzymes such as glutathione S-transferase and epoxide hydrolase. As part of a program in evaluating the chemopreventive potential of 2-AP, we have determined its effects on hepatotoxicity, mutagenicity and tumorigenicity of vinyl carbamate (VC), a prototypic hepatocarcinogen preferentially activated by P450 2E1 to the ultimate carcinogenic metabolite vinyl carbamate epoxide (VCO), which undergoes detoxification by glutathione conjugation and oxirane hydrolysis. Administration of 2-AP (100 mg/kg body wt) to male Sprague-Dawley rats by gavage, 2 days, 1 day and 4 h prior to VC or VCO, markedly ameliorated the hepatotoxicity of these compounds as determined by decreased serum aspartate aminotransferase and alanine aminotransferase activities. Furthermore, 2-AP pre-treatment significantly suppressed the VC-induced hepatocarcinogenesis in infant male B6C3F1 mice. In a separate experiment, the multiplicities of skin tumors formed in female ICR mice treated with 5.8 micromol of VC or VCO were inhibited 58 and 70%, respectively, by pre-treatment with 2-AP by oral administration. The mutational spectrum of ras-oncogene in papillomas was not altered by 2-AP pre-treatment. 2-AP also inhibited the mutagenicity of VC in the Salmonella-microsome assay. Taken together, these findings suggest that 2-AP is a potential chemopreventive agent.   相似文献   
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The posterior and anterior longitudinal ligaments of the lumbar spine appear on magnetic resonance (MR) images as thin lines of very low signal intensity in all spin-echo sequences. They cover the periphery of the outer fibers of the anulus fibrosus on sagittal images. The lumbar spine of 17 patients with 19 disk herniations was prospectively evaluated with MR imaging, and these findings were correlated with surgical findings. At surgery the posterior ligament was found to be disrupted in eight cases and intact in 11. Absence of a low-signal peripheral line around the herniated nucleus pulposus (HNP) was the most reliable sign of ligament rupture (no false-negative or false-positive findings). The peripheral line appeared to be interrupted in four cases, two of which were falsely positive. The two false-positive cases were related to a chemical shift artifact between epidural fat and the HNP. Presence of a normal and continuous peripheral line outlining the HNP excluded ligament disruption. The overall sensitivity for detecting disruption was 100%, and the specificity was 78%.  相似文献   
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900.
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