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991.
992.
Numerous whole-body vibration (WBV) devices of various forces are available on the market, although their influence on the musculoskeletal system is not yet understood. The effect of different WBVs on bone healing and muscle function was evaluated in rats ovariectomized at 3 months of age. 2 months after ovariectomy, bilateral metaphyseal tibia osteotomy and T-plate osteosynthesis were performed. Rats were divided into groups: intact, OVX, and OVX exposed to vertical WBVs of 35, 50, 70, or 90 Hz (experiment 1) or horizontal WBVs of 30, 50, 70, or 90 Hz (experiment 2) 5 days after osteotomy (0.5 mm, 15 min/day for 30 days). The tibia and gastrocnemius and soleus muscles were collected. Vertical vibrations (>35 Hz) improved cortical and callus densities, enlarged callus area and width, suppressed the tartrate-resistant acid phosphatase gene, enhanced citrate synthase activity, accelerated osteotomy bridging (35 and 50 Hz), upregulated the osteocalcin (Oc) gene (70 Hz), and increased relative muscle weight (50 Hz). Horizontal vibrations reduced cortical width (<90 Hz) and callus density (30 Hz), enhanced alkaline phosphatase (Alp) gene expression (50 Hz), decreased the size of oxidative fibers (35 and 70 Hz), and increased capillary density (70, 90 Hz). Biomechanical data; serum Oc, Alp, and creatine kinase activities; body weight; and food intake did not change after WBVs. Vertical WBVs of 35 and 50 Hz produced more favorable results than the higher frequencies. Horizontal WBV showed no positive or negative effects. Further studies are needed to elucidate the effects of WBV on different physiological systems, and precautions must be taken when implementing WBV in the treatment of patients.  相似文献   
993.
994.
BackgroundPeripheral arterial disease (PAD) is frequently underdiagnosed in the clinical practice, leading to a lack of opportunity to detect subjects at a high risk for cardiovascular (CV) death. The ankle-brachial pressure index (ABI) represents a noninvasive, objective tool to diagnose PAD and to predict adverse outcome.MethodsABI was determined by means of Doppler velocimetry, in 707 patients, aged 50 years or older, consecutively hospitalized in an internal medicine ward, who were followed-up for at least 12 months in order to assess all-cause and CV mortality.ResultsSymptomatic PAD affected 8% of the population while the prevalence of PAD, defined as ABI < 0.90, was 29%; high ABI (> 1.40) was found in 8% of the patients. After a mean follow-up period of 1.6 years, both low and high ABI were independently associated with CV mortality with a hazard ratio of 1.99 (p = 0.016) for low and 2.13 (p = 0.04) for high ABI, compared with normal ABI (0.90–1.40). High ABI also independently predicted all-cause mortality with a hazard ratio of 1.77 (p = 0.04).DiscussionABI measurement reveals a large number of individuals with asymptomatic PAD among those hospitalized in an internal medicine department. An increased mortality was observed in patients with both low and high ABI. Hospital admission for any reason may serve as an opportunity to detect PAD and start appropriate preventive actions.  相似文献   
995.
We wanted to evaluate the cutaneous synthesis of 25OHD and cholecalciferol after one whole-body exposure to ultraviolet radiation type B (UVB) in a randomized setup. Healthy volunteers were randomized to one whole-body exposure in a commercial tanning bed with UVB emission (UVB/UVA ratio 1.8-2.0%) or an identical placebo tanning bed without UVB. The output in the 280-320?nm range was 450?μW/cm(2). Blood samples were analyzed for 25OHD and cholecalciferol at baseline and during 7?days after treatment. We included 20 volunteers, 11 to UVB and 9 to placebo treatment. During the first 6?h, no significant differences in 25OHD between the groups were found. At the end of the study, we found a mean increase of 25OHD in the UVB group of 4.5?nmol/l (SD 7?nmol/l) compared to a decline of -1.2?nmol/l (SD 7?nmol/l) in the placebo group (p?=?0.1). A linear mixed model yielded an increase of 25OHD in the UVB group of 1.0?nmol/l per 24?h (p?相似文献   
996.
997.
Background: Adolescence is a critical developmental period when tobacco use is initiated and progression to regular smoking occurs. Another growing concern is the mounting evidence of ethnic/racial disparities in the smoking rates and adverse health consequences related to smoking. To reduce ethnic/racial disparities in smoking behaviors, understanding the protective influences against smoking behaviors among minority adolescents is important. Therefore, we examined the role of ethnic pride and parental disapproval of smoking on a wide range of smoking behaviors in ethnic/racial minority and White adolescents attending a suburban high school in Connecticut. Methods: A total of 870 adolescents (ethnic/racial minority: n= 202) completed questions on susceptibility to smoking, ever trying a cigarette, smoking at least one cigarette daily in the past 30 days, as well as parental disapproval of smoking and ethnic pride in a school-wide survey. Results: Logistic regression analyses indicated that perceived parental disapproval of adolescent smoking and ethnic pride were associated with susceptibility to smoking, ever trying a cigarette, and daily smoking differently for minority and White adolescents. For White youth, high parental disapproval of smoking was protective against all three smoking behaviors whereas ethnic pride was not. For minority youth, the combined protective effect of higher ethnic pride and higher parental disapproval of smoking was protective against all smoking behaviors. Conclusion: The protective role of parental disapproval of smoking and ethnic pride on smoking behaviors may inform culturally sensitive smoking interventions aimed at diverse, multi-ethnic youth, and future studies are needed to examine this. (Am J Addict 2012;21:424-434).  相似文献   
998.
We report on the first Neisseria gonorrhoeae isolate in the United States identified with high-level resistance to azithromycin. This report discusses the epidemiologic case investigation, the molecular studies of resistance-associated mutations and N. gonorrhoeae multiantigen sequence typing, and challenges posed by emerging gonococcal antimicrobial resistance.  相似文献   
999.
1000.
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