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11.
Obesity and osteoporosis are two important body composition problems with increasing prevalences in aged populations. Traditionally, obesity has been regarded as being beneficial to bone health. However, the protective effect of obesity on osteoporosis has been questioned. In some recent studies, obesity, as defined by percentage body fat, was regarded as a risk factor for osteoporosis. The purpose of this study was to (1) evaluate the effect of waist circumference, a surrogate measure for abdominal obesity, on bone mineral content (BMC) and (2) examine whether the effect of waist circumference increases with advancing age. The study population is made up of women aged over 45 years who completed the body composition and bone mineral density examinations in the fifth Korea National Health and Nutrition Examination Survey in 2010. Subjects who take estrogen or are under medical treatment for osteoporosis were excluded. Stroke patients are also excluded. Femoral neck, total-hip, and whole-body BMC were measured by dual-energy X-ray absorptiometry. A total of 1,434 subjects were included in the analysis. Waist circumference was negatively associated with BMC in all tested regions after correction for weight, menopausal status, smoking, drinking, and exercise. In addition, the negative association between waist circumference and BMC in the femoral neck and total hip increases with age, after correction for confounding factors, showing an interaction effect between waist circumference and age on BMC. In conclusion, this study shows that the negative relationship between waist circumference and BMC in the femoral neck and total hip is greater for older women.  相似文献   
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Parasitology Research - Giardia duodenalis is an important zoonotic protozoan parasite that infects humans and other animals. This study was conducted to investigate the prevalence and molecular...  相似文献   
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OBJECTIVE:

Aspiration can cause a variety of pulmonary syndromes, some of which are not well recognized. The objective of this study was to assess the demographic, clinical, radiological, and histopathological correlates of diffuse aspiration bronchiolitis (DAB), a bronchiolocentric disorder caused by recurrent aspiration.

METHODS:

This was a retrospective study of 20 consecutive patients with DAB seen at the Mayo Clinic in Rochester, Minnesota, between January 1, 1998 and June 30, 2014.

RESULTS:

The median age of the patients was 56.5 years (range, 22-76 years), and the male/female ratio was 2.3:1.0. In 18 patients, the diagnosis of DAB was based on the results of a lung biopsy; in the 2 remaining patients, it was based on clinical and radiological features, together with documented aspiration observed in a videofluoroscopic swallow study. In 19 patients (95%), we identified predisposing factors for aspiration, including gastroesophageal reflux disease (GERD), drug abuse, and dysphagia. Common presenting features included cough, sputum production, dyspnea, and fever. Twelve patients (60%) had a history of recurrent pneumonia. In all of the patients, chest CT revealed bilateral pulmonary infiltrates consisting of micronodules and tree-in-bud opacities. In the majority of patients, interventions aimed at preventing recurrent aspiration (e.g., anti-GERD therapies) led to improvement in the symptoms of DAB.

CONCLUSIONS:

Young to middle-aged subjects with recognizable predisposing factors for aspiration and who report a history of recurrent pneumonia are at increased risk for DAB. Although DAB is not well recognized, certain chest CT features are characteristic of the disorder.  相似文献   
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