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The association of knee extensor muscle strength with bone mineral density (BMD) has been reported in cross-sectional epidemiological studies, but it remains unclear whether or not this is the case with longitudinal change. Thus, we investigated whether or not the knee extension strength can predict the incidence of osteopenia or osteoporosis after 6 years, then compared the difference between sexes. Subjects were 1255 community-dwelling Japanese men and menopaused women, aged 40–81 years. BMD of lumbar spine and femoral neck was assessed by dual-energy X-ray absorptiometry twice at 6-year intervals. Subjects were divided into three groups, normal, osteopenia, and osteoporosis, depending on their young adult mean BMD % value. In the cross-sectional analysis the correlations between the knee extension strength and BMD of the two regions were examined, using Pearson’s correlation coefficient. Longitudinal analyses were then conducted to determine the odds ratio, controlled for age and BMI, given that those who were normal in the initial stage developed osteopenia or osteoporosis after 6 years, for every 1 SD decrease in knee extension strength, as well as those who first had normal or osteopenia and then developed osteoporosis. Cross-sectional analysis showed a statistically significant relation between knee extensor muscle strength and BMD at both the lumbar spine (p = 0.02) and the femoral neck (p < 0.0001) only in men. The longitudinal analysis showed the significant effect of muscle strength on the loss of femoral neck BMD from normal to osteopenia or osteoporosis both in men (OR 1.84, 95 % CI 1.36–2.48, p < 0.0001) and in women (OR 1.29, 95 % CI 1.002–1.65, p < 0.05), as well as on the loss of spinal BMD from normal or osteopenia to osteoporosis only in men (OR 2.97, 95 % CI 1.07–8.23, p < 0.05). The results suggest the importance of knee extension strength to maintain the bone health of the proximal femur and spine in aging particularly in men.  相似文献   
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Dynamic motion of the pelvic floor muscles during voiding was analyzed using real‐time magnetic resonance imaging. To evaluate the contraction of the pelvic floor muscles, striated urethral sphincter distance, levator ani muscle thickness and anterior fibromuscular stroma distance were measured. The percent contraction of the striated urethral sphincter from before voiding to just before initiation of voiding was 14% in the normal group and 5% in the voiding dysfunction group. The percent contraction of the anterior fibromuscular stroma from before voiding to just before initiation of voiding was 11% in the normal group and 1% in the voiding dysfunction group; the percent contraction of the muscles was significantly greater in the normal group (P < 0.05). Striated urethral sphincter and anterior fibromuscular stroma contraction at initiation of voiding open the bladder neck and urethra. This plays an important role in the smooth initiation of voiding.  相似文献   
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Several studies have shown that fasting blood glucose rises about 1-2 mg/dl/decade and post-prandial glucose by about 15 mg/dl/decade, leading to mild glucose intolerance with insulin resistance associated with aging. There appears to be a distinct group of individuals on an accelerated trajectory to clinically impaired glucose intolerance or frank type 2 diabetes mellitus. There are several characteristics of elderly onset type 2 diabetes as describe below. The incidence and progression of retinopathy were suggested to be rare. Several studies of the association between body mass index and cardiovascular mortality suggested the increased mortality associated with weight loss and underweight. Hypoglycemia is an underappreciated and potentially fatal complication of insulin and sulfonylurea treatment.  相似文献   
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A cross-sectional study of Japanese female commercial sex workers (FCSWs) working in massage parlors with cell baths (MPCBs) was conducted between July 1999 and December 2001. The study subjects were 171 FCSWs aged from 19 to 36 years. A questionnaire included sexual characteristics in addition to working name and date of birth. We serologically or bacteriologically confirmed the prevalence of HIV-1, HIV-2, hepatitis B virus (HBV), hepatitis C virus (HCV), Chlamydia trachomatis, Neisseria gonorrhoeae, syphilis, and trichomoniasis. There were no differences in the clinical characteristics of FCSWs working in standard-class MPCBs (group A) and those working in expensive-class MPCBs (group B). With respect to sexual characteristics, HIV-1 and HIV-2 were not confirmed in any subjects, but N. gonorrhoeae was detected in 1.2%. Use of condoms was 98.4% in group A and 83.3% in group B (P < 0.01). No HIV infection and an extremely low prevalence of sexually transmitted diseases (STDs) were recognized in Japanese FCSWs working in standard- and expensive-class MPCBs.  相似文献   
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