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Background
Physical activity has been associated with a decreased risk for breast cancer. The biological mechanismn(s) underlying the association between physical activity and breast cancer is not clear. Most prominent hypothesis is that physical activity may protect against breast cancer through reduced lifetime exposure to endogenous hormones either direct, or indirect by preventing overweight and abdominal adiposity. In order to get more insight in the causal pathway between physical activity and breast cancer risk, we designed the Sex Hormones and Physical Exercise (SHAPE) study. Purpose of SHAPE study is to examine the effects of a 1-year moderate-to-vigorous intensity exercise programme on endogenous hormone levels associated with breast cancer among sedentary postmenopausal women and whether the amount of total body fat or abdominal fat mediates the effects. 相似文献Background
This study aims to contribute to the knowledge of the influence of comorbidity in OA. The objectives of the study were (i) to describe the prevalence of comorbidity and (ii) to describe the relationship between comorbidity (morbidity count, severity and the presence of specific diseases) and limitations in activities and pain in elderly patients with knee or hip OA using a comprehensive inventory of comorbidity. 相似文献Background
Unprecedented declines in invasive breast cancer rates occurred in the United States between 2001 and 2004, particularly for estrogen receptor-positive tumors among non-Hispanic white women over 50 years. To understand the broader public health import of these reductions among previously unstudied populations, we utilized the largest available US cancer registry resource to describe age-adjusted invasive and in situ breast cancer incidence trends for non-Hispanic white women aged 50 to 74 years overall and by county-level rural/urban and poverty status. 相似文献Despite microvascular free tissue transfer being the mainstay of care in the reconstruction of larger maxillofacial defects, a significant number of patients experience postoperative complications due to impaired blood supply of the flap. In this context, the early influence of recipient bed perfusion remains unclear, but there is evidence that it is associated with free flap viability immediately after surgery.
MethodsWe analyzed flap and recipient bed perfusion within the first 2 weeks after surgery by using the oxygen-to-see device. One hundred ninety-one patients who underwent free flap surgery in our department were included.
ResultsFlow parameters were higher and postoperative complications were less frequent in radial forearm free flaps compared to any other type of flap. Flow parameters of the recipient bed were higher than transferred tissue at all times, implicating flap autonomization is not completed within 2 weeks. Previous radiotherapy significantly decreased flow parameters of the recipient bed but not of the flaps. Furthermore, irradiated patients with postoperative complications were found to have reduced flow parameters of their recipient bed compared to non-irradiated patients with postoperative complications.
ConclusionWe conclude that monitoring of recipient bed perfusion is useful for detecting flap compromise of irradiated patients in the early postoperative period.
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