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Background and objectives: The aim of this study is to show data regarding trends in the diagnosis of melanoma over the last ten years by looking at the University Clinic of Dermatology in Vienna as an example. Patients and methods: All excised melanocytic lesions from 1998 to 2008 were included. Results: The ratio of excisions of benign to malignant lesions fell from 7:1 (1998) to 4:1 (2008). The mean percentage of in situ melanomas was 39% in 1998 and did not change significantly over time and no change was seen in tumor thickness of invasive melanomas. The median invasion depth was 0.7 mm in 1998 and 0.65 mm in 2008. The absolute number of diagnosed melanomas did not change significantly over time. Conclusion: The proportion of in situ melanomas was consistently high. Tumor thickness stayed at a low level, whereas the number of excised benign melanocytic lesions decreased significantly.  相似文献   
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BackgroundIn patients with anterior knee pain and patellar instability, a specific training of the quadriceps muscle – especially the vastus medialis – is often recommended, although the practicability is discussed controversially and the proof of a measurable clinical effect is difficult. Therefore, this in vitro study investigates the influence of asymmetric muscle loading on the motion of the human patella.MethodsSeven human knee specimens were tested in a specially developed knee simulator. During simulated weight-bearing knee flexion, the kinematics of tibia, femur and patella were measured using an ultrasound motion capture system. The quadriceps forces were controlled to achieve a constant ankle force over the whole flexion range which is assumed to represent almost physiological loading. Three different force distributions of the quadriceps were tested — a central, equally distributed load as well as mainly lateral and medial loads.ResultsA significant influence of different quadriceps force distributions was found for patellar tilt around a proximodistal axis (up to 1.7°) and patellar rotation around an anteroposterior axis (up to 3.8°) with respect to the femur. Interestingly, the patellar mediolateral shift was influenced only marginally (< 1.5 mm).ConclusionsSpecific muscle training might help patients with patellofemoral pain and cartilage damage by a slight modification of the kinematics, but we could show that even highly asymmetric quadriceps loads only led to a small alteration of the mediolateral shift in case of a physiologic anatomy of the trochlear groove.  相似文献   
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Breast cancer is a systemic disease with a primarily local component. Besides surgical resection and irradiation of the locoregional tumor setting, central therapeutic aim is the elimination of disseminated micrometastatic tumor cells using cytostatic and/or hormonal treatment. Nevertheless, in the course of time a majority of patients suffer from systemic recurrence in the form of distant metastases. Intriguingly, in this connection, intratumoral cytotoxic T lymphocytes might serve as independent predictors of treatment efficacy and clinical outcome. Loss of immune balance (tumor dormancy) during intensive cross talk between T cells and tumor cells in the bone marrow microenvironment is suggested one reason for distant metastatic relapse. In this clinical context, further supportive therapies become increasingly attractive, taking immunological features of breast cancer cells into special account. The present review aims to dissect bone marrow-derived cellular antitumor immune responses and translational immunologic treatment options regarding their actual relevance to patients’ clinical benefit and their future directions in breast cancer management.  相似文献   
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The thymus plays distinct roles in the pathogenesis of the different Myasthenia gravis (MG) subtypes. Inflammatory, neoplastic and age-related alterations of the thymus are of pivotal relevance for the initiation of anti-acetylcholine receptor (AChR) autoimmunity in early onset MG, thymoma-associated MG and, likely, late onset MG, respectively. By contrast, the thymus is presumably not related to MG that is due to autoantibodies to the muscle specific kinase, MuSK. Finally, the role of the thymus is still obscure in MG defined by antibodies against the agrin receptor LRP4 and in MG without all of the above autoantibdies (triple sero-negative MG) since these MG subtypes have been described only recently and thymectomy has not been their standard treatment. This review aims to give an update on intrathymic mechanisms of tolerance breakdown in MG, including abnormal T cell selection and activation, the role of thymic myoid cells, the autoimmune regulator (AIRE) and regulatory T cells.  相似文献   
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