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Summary In view of the variety of 3D representation techniques, a clinical study was carried out in order to evaluate their respective usefulness. It appears that a single technique cannot be claimed to be valid for all clinical situations and that a combination of representations brings more relevant information. Among the different techniques a clear delineation must be established between those which allow the accurate definition of landmarks (multiplanar reformation, surface representation), and those which do not (integral shading, reconstructed radiology). The main point is the possibility to recognize anatomical landmarks on these latter modes and to choose oblique cut planes in relation to them. Visualization quality is strongly dependent upon the acquisition protocol which must provide a spatial resolution as isotropic as possible.
Une revue de différents modes de visualisation en haute résolution d'un objet volumique avec des applications
Résumé Face à la variété des techniques de représentation 3D une étude clinique a été conduite pour évaluer leurs utilités respectives. Il apparait qu'une technique unique ne peut pas convenir à toutes les situations cliniques et qu'une combinaison de différents modes de présentation apporte une information plus pertinente. Parmi les différentes techniques une distinction claire doit être établie entre celles qui autorisent la prise de repères précis (reformatage multiplanaire, représentation de surface), et celles qui ne le permettent pas (ombrage intégral, radiologie reconstruite). Le point principal est la possibilité de reconnaître des repères anatomiques sur ces derniers modes et de choisir des plans de coupe en relation avec eux. La qualité de la visualisation dépend étroitement du protocole d'acquisition qui doit fournir une résolution aussi isotrope que possible.
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Twenty-six methicillin-resistantStaphylococcus aureus strains were genetically differentiated by interrepeat PCR and the results compared with those of ribotyping, pulsed-field gel electrophoresis (PFGE) and random amplified polymorphic DNA analysis obtained in a previous study for the same strains. The comparison showed that the PCR-mediated assays were as discriminatory as PFGE, whereas ribotyping was the least powerful genotyping method. Due to the ease of performance, PCR fingerprinting may become the method of choice for establishing clonal relationships amongStaphylococcus aureus isolates.  相似文献   
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Authors present specially adapted visual acuity charts for "low vision" patients. For them refraction must be surveyed as often as possible.  相似文献   
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Chronic alcohol consumption is known to result in tissue injury, particularly in the liver, and is considered a major risk factor for cancers of the upper respiratory tract. Here we assessed the oxidative effects of subchronic ethanol consumption on DNA and lipids by measuring biomarkers 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG) and malondialdehyde (MDA), respectively. Physiological responses of pigs (n = 4) administered ethanol in drinking water for 39 days were compared with those of water-fed pigs (n = 4). Alcoholisation resulted in serum ethanol concentration of 1.90 g L?1 and in a moderate but significant increase in alanine aminotransferase activity, an index of liver injury. However, between the alcoholised and control groups there were no significant differences in the levels of 8-oxodG (8-oxodG per 106 2′deoxyguanosine) from leucocytes (2.52 ± 0.42 Vs 2.39 ± 0.34) or from target organs, liver, cardia and oesophagus. Serum MDA levels were also similar in ethanol-fed pigs (0.33 ± 0.04 μM) and controls (0.28 ± 0.03 μM). Interestingly, levels of 8-oxodG in cardia were positively correlated with those in oesophagus (Spearman correlation coefficient R = 1, P < 0.0001). Our results suggest that alcohol consumption may not cause oxidative damage to DNA and lipids as measured by 8-oxodG and MDA, respectively. The duration of alcoholisation and the potential alcohol-induced nutritional deficiency may be critical determinants of ethanol toxicity. Relevant biomarkers, such as factors involved in sensitization to ethanol-induced oxidative stress are required to better elucidate the relationship between alcohol consumption, oxidative stress and carcinogenesis.  相似文献   
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Objectives. We examined the probability of an obese person attaining normal body weight.Methods. We drew a sample of individuals aged 20 years and older from the United Kingdom’s Clinical Practice Research Datalink from 2004 to 2014. We analyzed data for 76 704 obese men and 99 791 obese women. We excluded participants who received bariatric surgery. We estimated the probability of attaining normal weight or 5% reduction in body weight.Results. During a maximum of 9 years’ follow-up, 1283 men and 2245 women attained normal body weight. In simple obesity (body mass index = 30.0–34.9 kg/m2), the annual probability of attaining normal weight was 1 in 210 for men and 1 in 124 for women, increasing to 1 in 1290 for men and 1 in 677 for women with morbid obesity (body mass index = 40.0–44.9 kg/m2). The annual probability of achieving a 5% weight reduction was 1 in 8 for men and 1 in 7 for women with morbid obesity.Conclusions. The probability of attaining normal weight or maintaining weight loss is low. Obesity treatment frameworks grounded in community-based weight management programs may be ineffective.Overweight and obesity are growing global health concerns.1 Strategies to control obesity emphasize obesity management and weight reduction as well as obesity prevention. In the United Kingdom, a national strategy report recommends that the management of obesity be an integral part of clinical practice.2 This envisages that patients may transition from obesity to a more healthy body weight. A target of 5% body weight loss is often recommended for obese individuals who intend to lose weight.3 However, access to weight management interventions may be limited,4 and weight management interventions have only small and poorly maintained effects on body weight.5,6 To understand the frequency with which reductions in body mass index (BMI, defined as weight in kilograms divided by the square of height in meters) may occur in a large population, we estimated the probability of an obese individual attaining normal body weight or a reduction of 5% in body weight.  相似文献   
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AimsOral therapies, including hormone‐based or targeted therapies, have recently taken an increasing place in cancer treatment. In this context, a state of the art of the available studies dealing with the adherence of adult patients to oral anticancer treatment is warranted. The purpose of this review is to address (i) the association between assessment methods and measured adherence, (ii) the putative factors related to adherence and (iii) new ways of improving adherence to oral cancer therapies.MethodsWe conducted a literature‐based narrative review of studies obtained from Pubmed using medical subject heading terms and free‐text terms combining concepts related to oral anticancer medication and adherence.ResultsThe analysis is based on 48 studies published since 1990, mostly assessing hormone‐based therapy in breast cancer and targeted therapies in chronic myeloid leukaemia. Various methods of adherence were reported including self‐report, medication measurement or combinations of methods. Adherence rates were found to vary from 14% to 100%. Beside patient related‐factors, adherence rate discrepancies were found to be dependent on the method used. Furthermore, there was no consensual definition of adherence even regarding the same methods, some of them tolerating a period of interruption during the treatment period. Finally, several studies addressing persistence found a progressive decrease in adherence with time.ConclusionAdherence to novel oral therapies is a major issue and further research is warranted to standardize adherence assessment in clinical studies better and to define better the most appropriate approaches to improve long term adherence in oncology practice.  相似文献   
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