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排序方式: 共有457条查询结果,搜索用时 8 毫秒
91.
Demographic changes resulting in ageing of the world's population have major implications for health. As men grow older, circulating levels of the principal androgen or male sex hormone testosterone (T) decline, while the prevalence of ill-health increases. Observational studies in middle-aged and older men have shown associations between lower levels of T and poorer mental health in older men, including worse cognitive performance, dementia and presence of depressive symptoms. The role of T metabolites, the more potent androgen dihydrotestosterone (DHT) and the oestrogen receptor ligand estradiol (E2) in the pathophysiology of cognitive decline are unclear. Studies of men undergoing androgen deprivation therapy in the setting of prostate cancer have shown subtle detrimental effects of reduced T levels on cognitive performance. Randomised trials of T supplementation in older men have been limited in size and produced variable results, with some studies showing improvement in specific tests of cognitive function. Interventional data from trials of T therapy in men with dementia are limited. Lower levels of T have also been associated with depressive symptoms in older men. Some studies have reported an effect of T therapy to improve mood and depressive symptoms in men with low or low-normal T levels. T supplementation should be considered in men with a diagnosis of androgen deficiency. Beyond this clinical indication, further research is needed to establish the benefits of T supplementation in older men at risk of deteriorating cognition and mental health. 相似文献
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The relationship between bone mineral density and ultrasound in postmenopausal and osteoporotic women 总被引:3,自引:0,他引:3
The aim of this cross-sectional study was to use a novel method of data analysis to demonstrate that patients with osteoporosis
have significantly lower ultrasound results in the heel after correcting for the effect of bone mineral density (BMD) measured
in the spine or hip. Three groups of patients were studied: healthy early postmenopausal women, within 3 years of the menopause
(n=104, 50%), healthy late postmenopausal women, more than 10 years from the menopause (n=75, 36%), and a group of women with osteoporosis as defined by WHO criteria (n=30, 14%). Broadband ultrasound attenuation (BUA), speed of sound (SOS) and Stiffness were measured using a Lunar Achilles
heel machine, and BMD of the lumbar spine and left hip was measured using dual-energy X-ray absorptiometry (DXA). SOS, BUA
and Stiffness were regressed against lumbar spine BMD and femoral BMD for all three groups combined. The correlation coefficients
were in the range 0.52–0.58, in agreement with previously published work. Using a calculated ratio R, analysis of variance
demonstrated that the ratio was significantly higher in the osteoporotic group compared with the other two groups. This implied
that heel ultrasound values are proportionately lower in the osteoporotic group compared with the other two groups for an
equivalent value of lumbar spine and femoral neck BMD. We conclude that postmenopausal bone loss is not associated with different
ultasound values once lumbar spine or femoral neck BMD is taken into account. Ultrasound does not give additional information
about patterns of bone loss in postmenopausal patients but is important in those patients with osteoporosis and fractures. 相似文献
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Histamine releasing activity of chandonium iodide and d-tubocurarine was studied in guinea pig ileum (in vitro), guinea pig peritoneum (in vivo) and in human volunteers (in vivo) by intradermal testing at dilutions of 1:1,000 and 1:10,000 of the clinical dosage of drugs. d-tubocurarine revealed significant histamine releasing activity in in vivo animal experiments and high incidence of positive intradermal reaction, 53.5 per cent and 13.5 per cent, in human volunteers. Chandonium iodide neither showed histamine releasing activity in animals nor in man. In clinical terms, chandonium iodide appears to be a safe neuromuscular blocking agent.KEY WORDS: Neuromuscular blocking agent, Histamine releasing activity, Chandonium iodide 相似文献
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Criticism of medical professionals is on the rise. The perception of the medical profession and the media, which educates the clientele, is widely different. The likely causes for dissatisfaction of the clientele and some possible solutions are presented.KEY WORDS: Armed Forces Medical Services, Medical care, Cost effective 相似文献
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Nicole J. Look Hong Francis J. Hornicek David C. Harmon Edwin Choy Yen-Lin Chen Sam S. Yoon G. Petur Nielsen Jackie Szymonifka Beow Y. Yeap Thomas F. DeLaney John T. Mullen 《European journal of cancer (Oxford, England : 1990)》2013,49(4):875-883
BackgroundPatients with large, high-grade extremity and truncal soft tissue sarcomas (STS) are at considerable risk for recurrence. A regimen of pre-operative chemotherapy consisting of mesna, adriamycin, ifosfamide and dacarbazine (MAID), interdigitated with radiotherapy (RT), followed by resection and post-operative chemotherapy with or without RT, has demonstrated high rates of local and distant control. The goal of this study is to assess outcomes in a recent cohort of patients treated on this regimen.MethodsWe retrospectively reviewed records of 66 consecutive patients with STS of the extremity or trunk who were treated with the aforementioned regimen from May 2000 to April 2011. Clinicopathologic characteristics and patient outcomes were analysed.ResultsSixty-six patients were analysed and were equally divided between grade 2 and 3 tumours. Margins were negative in 57 (89%) patients and positive in seven (11%) patients. At a median follow-up of 46 months, there were six (9%) locoregional and 20 (30%) distant recurrences. The locoregional and distant 5-year recurrence-free survival (RFS) rates were 91% and 64%, respectively. The 5-year overall (OS) and disease-specific survival rates were 86% and 89%, respectively. There were no treatment-related deaths or secondary myelodysplasias. Thirty-four (52%) patients had grade 3 or 4 acute haematologic chemotherapy-related toxicity. There were no statistically significant predictors of OS or RFS.ConclusionsFor a contemporary cohort of patients with high-risk extremity and truncal STS, a regimen of neoadjuvant chemoradiotherapy and surgery continues to result in high rates of survival with tolerable short- and long-term toxicity. 相似文献