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51.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Schon in der frühen Phase der global sehr verschieden verlaufenden COVID-19-Pandemie zeigten sich Hinweise auf den Einfluss...  相似文献   
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Duchenne muscular dystrophy (DMD), a severe X-linked recessive disorder which results in progressive muscle degeneration, is due to a lack of dystrophin, a membrane cytoskeletal protein. An approach to treatment is to compensate for dystrophin loss with utrophin, another cytoskeletal protein with over 80% homology with dystrophin. Utrophin is expressed, at the neuromuscular junction, in normal and DMD muscles and there is evidence that it may perform the same cellular functions as dystrophin. So, the identification of molecules or drugs that could up-regulate utrophin is a very important goal for therapy. We show that in adult normal and mdx mice (an animal model of Duchenne myopathy) treated with -arginine, the substrate of nitric oxide synthase (NOS), a pool of utrophin localized at the membrane appeared and increased, respectively. In normal and mdx myotubes in culture, -arginine, nitric oxide (NO), or hydroxyurea increased utrophin levels and enhanced its membrane localization. This effect did not occur with -arginine, showing the involvement of NOS in this process. The NO-induced increase in utrophin was prevented by oxadiazolo-quinoxalin-1-one, an inhibitor of a soluble guanylate cyclase implicated in NO effects. These results open the way to a potential treatment for Duchenne and Becker dystrophies.  相似文献   
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PURPOSE: The rate of testicular cancer is increasing. Trauma severe enough to cause testicular atrophy is a putative risk factor for testicular cancer but the epidemiological evidence is not conclusive. A population based, multicenter case-control study was performed from 1995 to 1997 to investigate potential risk factors for gonadal and extragonadal germ cell cancer. MATERIALS AND METHODS: The study was done in 5 German regions. Interviews were performed with 269 eligible male patients with a histologically verified diagnosis and 797 controls. Detailed information on medical and family history was collected at personal interviews. RESULTS: We identified a significantly elevated risk for testicular cancer in relation to testis and/or groin trauma (odds ratio 2.5, 95% confidence interval [CI] 1.51 to 4.20). After introducing a lag time by excluding reports of trauma within the last 12 months before diagnosis or interview the corresponding odds ratio was 2.1 (95% CI 1.24 to 3.61). Analysis of the circumstances and the reported types of injury allowed us to restrict the study to testis trauma specifically, which had an odds ratio of 3.49 (95% CI 1.78 to 6.81). To account for a potential reporting bias analysis was restricted to traumatic episodes for which medical attention was sought. This restriction resulted in an odds ratio of 0.70 (95% CI 0.19 to 2.63) after excluding from study trauma reports within the last 12 months. CONCLUSIONS: The results of our study do not support the hypothesis that testicular trauma is an important risk factor for testicular cancer. The possibility of recall bias should be considered.  相似文献   
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Endoscopic screening (sigmoidoscopy, colonoscopy) with removal of precancerous lesions can prevent a large proportion of colorectal cancers (CRCs). However, there is lack of data regarding optimal age, time intervals and numbers of screening examinations. We developed and applied modified techniques of epidemiological analysis to evaluate the impact of various endoscopy-based screening strategies on prevention of clinically manifest CRCs between the ages of 50 and 79 in a population-based case-control study (294 cases, 254 controls) conducted in Saarland, Germany. We found a strong potential for reduction of CRC occurrence even with a single screening endoscopy. The optimal age for a single screening endoscopy appears to be around 55 (estimated potential for prevention of cases between the ages of 55 and 79 in case of 100% compliance: 77% (95% confidence interval (CI) 46-90%)). A single screening endoscopy at age 50 would have a lower impact due to failure to prevent CRC at higher ages. Similarly, screening at ages 60 or older would have a lower impact because it would fail to prevent CRC at lower ages. Repeated offers of screening examinations could provide substantial additional benefit with the levels of compliance to be expected in practice, but they would have to be weighed against the increased risks and costs.  相似文献   
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BackgroundThe question of how to deal with B3 lesions is of emerging interest.MethodsIn the breast diagnostics of 192 patients between 2009 and 2016, a minimally invasive biopsy revealed a B3 lesion with subsequent resection. This study investigates the malignancy rate of different B3 subgroups and the risk factors that play a role in obtaining a malignant finding.ResultsThe distribution of B3 lesions after minimally invasive biopsy was as follows: atypical ductal hyperplasia (ADH), 7.3%; flat epithelial atypia (FEA), 7.8%; lobular neoplasia (LN), 7.8%; papilloma (Pa), 49.5%; phylloidal tumour (PT), 8.9%; radial sclerosing scar (RS), 3.1%; mixed findings, 10.4%; and other B3 lesions, 5.2%. Most B3 lesions were detected by stereotactic vacuum-assisted biopsy (44.3%), 36.5% by ultrasound-assisted biopsy, and 19.3% by magnetic resonance imaging-assisted biopsy. Most B3 lesions (55.2%) were verified by surgical resection, whereas 30.7% were downgraded to a benign lesion. About 14.1% of the cases were upgraded to malignant lesions, 9.4% to ductal carcinoma in situ and 4.7% to invasive carcinoma. In relation to individual B3 lesions, the following malignancy rates were found: 28.6% (ADH), 13.3% (FEA), 33.3% (LN), 12.6% (Pa), 5.9% (PT), and 0% (RS). The most important risk factor was increasing age. Postmenopausal status was considered an increased risk for an upgrade (p = 0.015). A known malignancy in the ipsilateral breast was a significant risk factor for a malignant upgrade (p = 0.003).ConclusionIncreasing knowledge about B3 lesions allows us to develop a “lesion-specific” therapy approach in the heterogeneous group of B3 lesions, with follow-up imaging for some lesions with less malignant potential and concordance with imaging or further surgical resection in cases of disconcordance with imaging or higher malignant potential.  相似文献   
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BackgroundRisk-adjusted cancer screening and prevention is a promising and continuously emerging option for improving cancer prevention. It is driven by increasing knowledge of risk factors and the ability to determine them for individual risk prediction. However, there is a knowledge gap between evidence of increased risk and evidence of the effectiveness and efficiency of clinical preventive interventions based on increased risk. This gap is, in particular, aggravated by the extensive availability of genetic risk factor diagnostics, since the question of appropriate preventive measures immediately arises when an increased risk is identified. However, collecting proof of effective preventive measures, ideally by prospective randomized preventive studies, typically requires very long periods of time, while the knowledge about an increased risk immediately creates a high demand for action.SummaryTherefore, we propose a risk-adjusted prevention concept that is based on the best current evidence making needed and appropriate preventive measures available, and which is constantly evaluated through outcome evaluation, and continuously improved based on these results. We further discuss the structural and procedural requirements as well as legal and socioeconomical aspects relevant for the implementation of this concept.  相似文献   
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