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Background:  Acitretin has been shown to be effective for psoriasis treatment. Its mechanism of action is not completely understood, and there are few studies focusing on histological and immunohistochemical differences before and after treatment of psoriasis with acitretin.
Methods:  This is a prospective study of 17 patients with plaque psoriasis treated with acitretin for 4 months with biopsies taken before and after therapy. Histological features and immunohistochemical reactions to cytokeratin (CK) 10, CK16, CK19, Ki67 and CD1a were evaluated and compared.
Results:  There were nine men and eight women with median age of 47 years. Epidermal thickness, CK16 positivity, Ki67 and CD1a-positive cell index reduced after treatment (p < 0.01). Suprapapillary plate thickness stayed the same (p > 0.05) although the epidermal/suprapapillary thickness ratio was significantly higher before treatment (p < 0.01). CK10 positivity was lower and a thicker basal cell layer was seen in the epidermis before treatment (p < 0.01). CK19 was negative in all cases.
Conclusions:  Acitretin therapy improved histological and immunohistochemical features typical of psoriasis. In psoriasis, suprapapillary plates are not thin, but the epidermal/suprapapillary thickness ratio is increased. Basal cell layer is expanded in psoriasis. Langerhans' cells were less frequent after treatment, and that finding has to be investigated further to determine its role in acitretin mechanism of action.  相似文献   
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Background:We report on the outcomes in aged patients with severe, treatment-resistant depression or psychosis who were given ongoing outpatient continuation-maintenance ECT of varying duration to prevent remission and relapse following a successful course of acute ECT.Methods:A retrospective chart review of 58 consecutive patients of three Australian aged psychiatry services comparing the number and length of psychiatric admissions before and after the start of continuation-maintenance ECT.Results:Four patients had only one treatment and two received over 50 (mean 14.7). Five were still enrolled in a maintenance program two years later. In the two years after continuation-maintenance ECT started, admissions fell by 53% in number and 79% in duration compared with the previous two years. Within the actual treatment period which varied from one patient to another, admissions fell by 90% in number and 97% in duration compared with the same period beforehand.Conclusion:A treatment effect cannot be proven but the severity and chronicity of patients' conditions make placebo effects and spontaneous remission unlikely. Randomised, controlled trials are almost impossible in this setting and so carefully conducted reviews and case–control studies are still of value. Our findings suggest that continuation-maintenance ECT is effective in carefully selected patients at high risk of relapse.  相似文献   
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Clinical trials are the gold standard for generating reliable medical evidence. The biggest bottleneck in clinical trials is recruitment. To facilitate recruitment, tools for patient search of relevant clinical trials have been developed, but users often suffer from information overload. With nearly 700 coronavirus disease 2019 (COVID-19) trials conducted in the United States as of August 2020, it is imperative to enable rapid recruitment to these studies. The COVID-19 Trial Finder was designed to facilitate patient-centered search of COVID-19 trials, first by location and radius distance from trial sites, and then by brief, dynamically generated medical questions to allow users to prescreen their eligibility for nearby COVID-19 trials with minimum human computer interaction. A simulation study using 20 publicly available patient case reports demonstrates its precision and effectiveness.  相似文献   
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We evaluate the prevalence of intestinal parasites in 504 people and the degree of association between environmental variables and parasites found in population, soil and water in a rural area of Argentina during 2002-2003. A structured survey was used to evaluate the environmental variables and fecal-human, soil and water samples were analyzed. The prevalence of parasites was 45.4%. Most prevalent protozoa were Blastocystis hominis (27.2%) and Giardia lamblia (6.9%), while the most prevalent helminth was Ascaris lumbricoides (3.8%). The analyzed environmental variables showing association (p < 0.05) with presence of parasites in population were: cardboard-tin or wooden house, dirt floor, home or communal water pump, faucet outside the house or public faucet and cesspool or latrine. Parasite forms were found in 82.3% of the soil samples and in 84.2% of the water samples. In both samples we found parasites that were also found in people. In this study we have found deficient sanitary conditions associated with presence of parasites in population and we have evidenced that contaminated soil and water were the source of these parasites.  相似文献   
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BACKGROUND: Although redefinition for acute myocardial infarction (AMI) has been proposed few years ago, to date it has not been universally adopted by many institutions. The purpose of this study is to evaluate the diagnostic, prognostic and economical impact of the new diagnostic criteria for AMI. METHODS: Patients consecutively admitted to the emergency department with suspected acute coronary syndromes were enrolled in this study. Troponin T (cTnT) was measured in samples collected for routine CK-MB analyses and results were not available to physicians. Patients without AMI by traditional criteria and cTnT > or = 0.035 ng/mL were coded as redefined AMI. Clinical outcomes were hospital death, major cardiac events and revascularization procedures. In-hospital management and reimbursement rates were also analyzed. RESULTS: Among 363 patients, 59 (16%) patients had AMI by conventional criteria, whereas additional 75 (21%) had redefined AMI, an increase of 127% in the incidence. Patients with redefined AMI were significantly older, more frequently male, with atypical chest pain and more risk factors. In multivariate analysis, redefined AMI was associated with 3.1 fold higher hospital death (95% CI: 0.6-14) and a 5.6 fold more cardiac events (95% CI: 2.1-15) compared to those without AMI. From hospital perspective, based on DRGs payment system, adoption of AMI redefinition would increase 12% the reimbursement rate [3552 Int dollars per 100 patients evaluated]. CONCLUSIONS: The redefined criteria result in a substantial increase in AMI cases, and allow identification of high-risk patients. Efforts should be made to reinforce the adoption of AMI redefinition, which may result in more qualified and efficient management of ACS.  相似文献   
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