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BACKGROUND: Decreased fitness of the lower extremities is a potentially modifiable fall risk factor. This study aimed to compare two exercise programs--square-stepping exercise (SSE), which is a low-cost indoor program, and walking--for improving the fitness of the lower extremities. METHODS: We randomly allocated 68 community-dwelling older adults (age 65-74 years) to either the SSE or walking group (W group). During the 12-week regimen, the SSE group participated in 70-minute exercise sessions conducted twice a week at a local health center, and the W group participated in outdoor supervised walking sessions conducted weekly. The W group was instructed to increase the number of daily steps. Prior to and after the program, we obtained information on 11 physical performance tests for known fall risk factors and 3 self-reported scales. The fall incidence was followed-up for 8 months. RESULTS: At 12 weeks postregimen, significant differences were observed between the two exercise groups with respect to leg power (1 item), balance (2 items), agility (2 items), reaction time (2 items), and a self-reported scale (1 item); the SSE group demonstrated a marked improvement in the above-mentioned items with Group x Time interactions. Significant time effects were observed in the tests involving chair stands, functional reach, and standing up from a lying-down position without Group x Time interactions. During the follow-up period, the fall rates per person-year in the SSE and W groups were 23.4% and 33.3%, respectively (p =.31). CONCLUSION: Although further studies are required, SSE is apparently more effective than walking in reducing fall risk factors, and it appears that it may be recommended as a health promotion exercise in older adults.  相似文献   
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Absent response of serum thyrotrophin (TSH) after stimulation with 200 micrograms synthetic thyrotrophin-releasing hormone (TRH) was used as a criterion of adequate suppression of TSH in the treatment of thyroid carcinoma patients with thyroxine. The mean causing total suppression of the response was 223 micrograms of thyroxine per day. At this dose level about 40% of the patients had serum thyroxine concentrations above the upper reference interval and only 10% had elevated triiodothyronine concentrations. In some patients the TSH response to TRH varied between absent and low normal when tested at long intervals. The ideal dose of thyroxine is obviously slightly higher than the smallest one causing total suppression of the TSH response to TRH, i.e. about 250 micrograms a day. The individual dose must be found using the TRH stimulation test because serum thyroid hormone levels cannot be used as a guideline for adequate dosage. In some patients the thyroid remnant of apparently normal thyroid tissue was not totally suppressed although the thyroxine dose was definitely above the level causing suppression of the response to TRH.  相似文献   
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Chitosan nanoparticles (NC) have excellent capacity for protein entrapment, favorable epithelial permeability, and are regarded as promising nanocarriers for oral protein delivery. Herein, we designed and evaluated a class of core shell corona nanolipoparticles (CSC) to further improve the absorption through enhanced intestinal mucus penetration. CSC contains chitosan nanoparticles as a core component and pluronic F127-lipid vesicles as a shell with hydrophilic chain and polyethylene oxide PEO as a corona. These particles were developed by hydration of a dry pluronic F127-lipid film with NC suspensions followed by extrusion. Insulin nested inside CSC was well protected from enzymatic degradation. Compared with NC, CSC exhibited significantly higher efficiency of mucosal penetration and, consequently, higher cellular internalization of insulin in mucus secreting E12 cells. The cellular level of insulin after CSC treatment was 36-fold higher compared to treatment with free insulin, and 10-fold higher compared to NC. CSC significantly facilitated the permeation of insulin across the ileum epithelia, as demonstrated in an ex vivo study and an in vivo absorption study. CSC pharmacological studies in diabetic rats showed that the hypoglycemic effects of orally administrated CSC were 2.5-fold higher compared to NC. In conclusion, CSC is a promising oral protein delivery system to enhance the stability, intestinal mucosal permeability, and oral absorption of insulin.  相似文献   
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ObjectiveTo investigate the effect of a lifestyle-related risk factor modification intervention on coronary artery disease (CAD) patients’ lifestyle changes.MethodA randomized controlled study was conducted in Nepal. A total of 224 CAD patients (112 in each study group) were included at baseline, and 196 patients (98 in each group) completed the one-month follow-up. Patients in the intervention group (IG) received nurse-led intervention in addition to the usual care. Face-to face and telephone interview was conducted using standard questionnaires to collect data on lifestyle-related risk factors; smoking, alcohol consumption, diet, body mass index, stress, adherence to medical therapy, and physical activity. General linear model repeated measure analysis was used to analyse the effects of the intervention.ResultsBased on self-reported data we found significant improvement in lifestyle-related risk factor habits in the IG compared with the usual care group with respect to diet (p < 0.001), physical activity (p < 0.001), medication adherence (p < 0.001) and stress (p < 0.001) at one-month follow-up.ConclusionLifestyle-related risk factor modification intervention can positively influence health risk habits, even when it is less intensive but supplemented with information leaflets.Practical implicationsNurse-led one-time intervention may successfully deliver counselling to improve healthy lifestyle among underserved CAD patients.  相似文献   
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OBJECTIVES: To study the association between different obesity indicators and walking limitation and to examine the role of C‐reactive protein (CRP) and handgrip strength in that association. DESIGN: A cross‐sectional, population‐based study. SETTING: The Health 2000 Survey with a representative sample of the Finnish population. PARTICIPANTS: Subjects aged 55 and older with complete data on body composition, CRP, handgrip strength, and walking limitation (N=2,208). MEASUREMENTS: Body composition, anthropometrics, CRP, medical conditions, handgrip strength, and maximal walking speed were measured in the health examination. Walking limitation was defined as maximal walking speed less than 1.2 m/s or difficulty walking half a kilometer. RESULTS: The two highest quartiles of body fat percentage and CRP and the two lowest quartiles of handgrip strength were all significantly associated with greater risk of walking limitation when chronic diseases and other covariates were taken into account. In addition, high CRP and low handgrip strength partially explained the association between high body fat percentage and walking limitation, but the risk of walking limitation remained significantly greater in persons in the two highest quartiles than in those in the lowest quartile of body fat percentage (odds ratio (OR)=1.75, 95% confidence interval (CI)=1.19–2.57 and OR=2.80, 95% CI 1.89–4.16). The prevalence of walking limitation was much higher in persons who simultaneously had high body fat percentage and low handgrip strength (61%) than in those with a combination of low body fat percentage and high handgrip strength (7%). Using body mass index and waist circumference as indicators of obesity yielded similar results as body fat percentage. CONCLUSION: Low‐grade inflammation and muscle strength may partially mediate the association between obesity and walking limitation. Longitudinal studies and intervention trials are needed to verify this pathway.  相似文献   
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Older adults who report environmental barriers in their neighborhood have a higher risk for walking difficulty. However, environmental facilitators that protect against walking difficulty are not well known. The objective of this study was to identify the effect of environmental facilitators for outdoor walking on development of walking difficulty in community-dwelling older people. This was a prospective study with a 3.5-year follow-up time on 261 community-dwelling people aged 75–81 years, who at baseline were able to walk 0.5 km without difficulty. Environmental facilitators for outdoor walking were self-reported with standardized questionnaires, including having features in one’s home which make it easy to access the outdoors, having a park or other green area within a walking distance from home, having outdoor recreational facilities within a walking distance from home, having features in the nearby environment, which are attractive for outdoor activities, and perceiving the surrounding environment or facilities nearby as motivating factors for physical activity. Self-reported difficulty in walking 0.5 km was assessed every 6 months. Of the participants, 46 % developed walking difficulty during the follow-up. Having a park or other green area within a walking distance from home was the most frequently reported facilitator. Environmental facilitators decreased the risk for development of walking difficulty, hazard ratio per item 0.86, (95 % confidence interval 0.73–1.02). The results indicate that the mobility of older community-dwelling people may be promoted with outdoor recreational facilities that are easy to access and located within a walking distance from home.  相似文献   
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