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61.
OBJECTIVES: This study sought to evaluate the associations between different measures of obesity and prevalent atherosclerosis in a large population-based cohort. BACKGROUND: Although obesity is associated with cardiovascular mortality, it is unclear whether this relationship is mediated by increased atherosclerotic burden. METHODS: Using data from the Dallas Heart Study, we assessed the association between gender-specific obesity measures (i.e., body mass index [BMI]; waist circumference [WC]; waist-to-hip ratio [WHR]) and prevalent atherosclerosis defined as coronary artery calcium (CAC) score >10 Agatston units measured by electron-beam computed tomography and detectable aortic plaque measured by magnetic resonance imaging. RESULTS: In univariable analyses (n = 2,744), CAC prevalence was significantly greater only in the fifth versus first quintile of BMI, whereas it increased stepwise across quintiles of WC and WHR (p trend <0.001 for each). After multivariable adjustment for standard risk factors, prevalent CAC was more frequent in the fifth versus first quintile of WHR (odds ratio 1.91, 95% confidence interval 1.30 to 2.80), whereas no independent positive association was observed for BMI or WC. Similar results were observed for aortic plaque in both univariable and multivariable-adjusted analyses. The c-statistic for discrimination of prevalent CAC was greater for WHR compared with BMI and WC in women and men (p < 0.001 vs. BMI; p < 0.01 vs. WC). CONCLUSIONS: We discovered that WHR was independently associated with prevalent atherosclerosis and provided better discrimination than either BMI or WC. The associations between obesity measurements and atherosclerosis mirror those observed between obesity and cardiovascular mortality, suggesting that obesity contributes to cardiovascular mortality via increased atherosclerotic burden.  相似文献   
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OBJECTIVE: To determine whether increasing advanced glycation end products (AGEs) in bovine articular cartilage to levels present in aged human cartilage modulates the tensile biomechanical properties of the tissue. METHODS: Adult bovine articular cartilage samples were incubated in a buffer solution with ribose to induce the formation of AGEs or in a control solution. Portions of cartilage samples were assayed for biochemical indices of AGEs and tested to assess their tensile biomechanical properties, including stiffness, strength, and elongation at failure. RESULTS: Ribose treatment of cartilage induced increases in tissue fluorescence, absorbance, and pentosidine content (P < 0.001 for each comparison) by amounts similar to those that occur during aging in humans. Ribose treatment of cartilage also induced an increase in dynamic modulus (60% increase) and strength (35% increase), and a decrease (25% decrease) in strain (P < 0.001 for each comparison). CONCLUSION: The concomitant increase in AGEs and alteration of tensile properties of cartilage after ribose treatment suggest that aging-associated changes in AGEs have functional consequences for this tissue. The AGE-associated increases in strength and stiffness of cartilage may be beneficial by counteracting the decreases in these properties that are associated with degeneration. Conversely, the AGE-associated decrease in failure length, or increase in brittleness, together with increased stiffness may predispose cartilage to increased stress concentration, fracture, and aging-associated biomechanical dysfunction.  相似文献   
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Performing diagnoses using virtual slides can take pathologists significantly longer than with glass slides, presenting a significant barrier to the use of virtual slides in routine practice. Given the benefits in pathology workflow efficiency and safety that virtual slides promise, it is important to understand reasons for this difference and identify opportunities for improvement. The effect of display resolution on time to diagnosis with virtual slides has not previously been explored. The aim of this study was to assess the effect of display resolution on time to diagnosis with virtual slides. Nine pathologists participated in a counterbalanced crossover study, viewing axillary lymph node slides on a microscope, a 23-in 2.3-megapixel single-screen display and a three-screen 11-megapixel display consisting of three 27-in displays. Time to diagnosis and time to first target were faster on the microscope than on the single and three-screen displays. There was no significant difference between the microscope and the three-screen display in time to first target, while the time taken on the single-screen display was significantly higher than that on the microscope. The results suggest that a digital pathology workstation with an increased number of pixels may make it easier to identify where cancer is located in the initial slide overview, enabling quick location of diagnostically relevant regions of interest. However, when a comprehensive, detailed search of a slide has to be made, increased resolution may not offer any additional benefit.  相似文献   
64.
Efficacy of a nicotine lozenge for smoking cessation   总被引:4,自引:0,他引:4  
BACKGROUND: Since nicotine gum was introduced in the 1980s, nicotine replacement therapy has become the most widely used pharmacological smoking cessation treatment. Some smokers prefer acute oral forms, but many smokers reject chewing gum. We tested the safety and efficacy of a new nicotine polacrilex lozenge for smoking cessation. METHODS: Double-blind, placebo-controlled, randomized clinical trial with parallel arms testing 2- and 4-mg nicotine lozenges. Smokers (n = 1818) were assigned to a lozenge dose on the basis of nicotine dependence, assessed by time to the first cigarette of the day. Low-dependence smokers were randomized to receive the 2-mg nicotine (n = 459) or placebo (n = 458) lozenge; high-dependence smokers, the 4-mg nicotine (n = 450) or placebo (n = 451) lozenge. We assessed abstinence at 6, 12, 24, and 52 weeks and analyzed craving and withdrawal symptoms. RESULTS: Treatment with the nicotine lozenge resulted in significantly greater 28-day abstinence at 6 weeks, for the 2-mg (46.0% vs. 29.7%; odds ratio [OR], 2.10; 95% confidence interval [CI], 1.59-2.79; P<.001) and the 4-mg (48.7% vs. 20.8%; OR, 3.69; 95% CI, 2.74-4.96; P<.001) lozenges, compared with placebo. Significant treatment effects were maintained for a full year. Smokers who used more lozenges achieved significantly better treatment effects. Use of the active lozenge also resulted in reduced craving and withdrawal. Most adverse events were moderate and resembled those seen with nicotine gum. CONCLUSION: The nicotine lozenge is a safe and effective new treatment for smoking cessation in low- and high-dependence smokers.  相似文献   
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Background

Neurodynamics is a clinical medium for testing the mechanical sensitivity of peripheral nerves which innervate the tissues of both the upper and lower limb. Currently, there is paucity in the literature of neurodynamic testing in osteopathic research, and where there is research, these are often methodologically flawed, without the appropriate comparators, blinding and reliability testing.

Aims

This study aimed to assess the physiological effects (measured through Range of Motion; ROM), of a commonly utilized cervical mobilization treatment during a neurodynamic test, with the appropriate methodology, i.e., compared against a control and sham. Specifically, this was to test whether cervical mobilization could reduce upper limb neural mechanical sensitivity.

Methodology

Thirty asymptomatic participants were assessed and randomly allocated to either a control, sham or mobilization group, where they were all given a neurodynamic test and ROM was assessed.

Results

The results showed that the mobilization group had the greatest and most significant increase in ROM with Change-Left p < 0.05 and Change-Right p < 0.05 compared against the control group, and Change-Left p < 0.01 and Change-Right p < 0.05 compared against the sham group.

Conclusions

This study has highlighted that, as expected, cervical mobilization has an effect at reducing upper limb neural mechanical sensitivity. However, there may be other factors interacting with neural mechanosensitivity outside of somatic influences such as psychological expectation bias. Further research could utilize the methodology employed here, but with other treatment areas to help develop neural tissue research. In addition to this, further exploration of psychological factors should be made such as utilizing complex top-down cognitive processing theories such as the neuromatrix or categorization theories to help further understand cognitive biases such as the placebo effect, which is commonly ignored in osteopathic research, as well as other areas of science, and which would further complete a holistic perspective.  相似文献   
69.
Introduction: Cardiac rehabilitation program is an evidence-based intervention and established model of exercise delivery following myocardial infarction and heart failure. Although it forms an important part of recovery and helps to prevent future events and complications, there has been little focus on its potential cognitive benefits.

Areas covered: Coronary artery disease and heart failure are common heart problems associated with significant morbidity and mortality, and cognitive decline is commonly seen in affected individuals. Cognitive impairment may influence patient self-management by reducing medication adherence, rendering patients unable to make lifestyle modifications and causing missed healthcare visits. Cognitive assessment in cardiac rehabilitation as an outcome measure has the potential to improve clinical, functional and behavioral domains as well as help to reduce gaps in the quality of care in these patients.

Expert commentary: Limited evidence at present has shown that cardiac rehabilitation and exercise has potential in preventing cognitive decline. Cardiac prehabilitation, a rehabilitation-like program delivered before cardiac surgery, may also play a role in preventing postoperative cognitive dysfunction, but needs future research studies to support it.  相似文献   

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