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101.
BackgroundKnee flexion strength may hold important clinical implications for the determination of injury risk and readiness to return to sport following injury and orthopedic surgery. A wide array of testing methodologies and positioning options are available that require validation prior to clinical integration. The purpose of this study was to 1) investigate the validity and test-retest reliability of isometric knee flexion strength measured by a fixed handheld dynamometer (HHD) apparatus compared to a Biodex Dynamometer (BD), 2) determine the impact of body position (seated versus supine) and foot position (plantar- vs dorsiflexed) on knee flexion peak torque and 3) establish the validity and test-retest reliability of the NordBord Hamstring Dynamometer.Study DesignValidity and reliability study, test-retest design.MethodsForty-four healthy participants (aged 27 ± 4.8 years) were assessed by two raters over two testing sessions separated by three to seven days. Maximal isometric knee flexion in the seated and supine position at 90o knee flexion was measured with both a BD and an externally fixed HHD with the foot held in maximal dorsiflexion or in plantar flexion. The validity and test-retest reliability of eccentric knee flexor strength on the NordBord hamstring dynamometer was assessed and compared with isometric strength on the BD.ResultsLevel of agreement between HHD and BD torque demonstrated low bias (bias -0.33 Nm, SD of bias 13.5 Nm; 95% LOA 26.13 Nm, -26.79 Nm). Interrater reliability of the HHD was high, varying slightly with body position (ICC range 0.9-0.97, n=44). Isometric knee flexion torque was higher in the seated versus supine position and with the foot dorsiflexed versus plantarflexed. Eccentric knee flexion torque had a high degree of correlation with isometric knee flexion torque as measured via the BD (r=0.61-0.86). The NordBord had high test-retest reliability (0.993 (95%CI 0.983-0.997, n=19) for eccentric knee flexor strength, with an MDC95 of 26.88 N and 28.76 N for the left and right limbs respectively.ConclusionCommon measures of maximal isometric knee flexion display high levels of correlation and test-retest reliability. However, values obtained by an externally fixed HHD are not interchangeable with values obtained via the BD. Foot and body position should be considered and controlled during testing.Level of Evidence2b  相似文献   
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BACKGROUND AND AIM: The aim of the study was to determine the effects on plasma cholesterol of replacing a plant sterol-enriched fat spread with carbohydrate-rich foods relative to a diet high in saturated fat. METHODS AND RESULTS: Twenty-nine men and women, from the general community, with mean age (SD) 48 (14)y, body mass index 29.0 (6.2)kg/m(2), and plasma total cholesterol concentration 6.48 (0.97)mmol/L completed the randomised, crossover dietary intervention. There were three diets: New Zealand diet (NZ diet) high in total (34%kJ) and saturated (15%kJ) fat, a cholesterol-lowering fibre-rich diet reduced in total (30%kJ) and saturated fat (8%kJ) but including a plant sterol spread (PS diet), and the same cholesterol-lowering diet with the plant sterol spread isocalorically replaced with carbohydrate (CHO diet); total fat, 26%kJ; saturated fat 7%kJ. All foods were provided and each diet was followed for four weeks. Mean (SD) plasma low-density lipoprotein cholesterol concentration declined from 4.68 (0.91)mmol/L on the high saturated fat diet to 4.12 (0.83)mmol/L (P<0.001) on the carbohydrate diet and 3.76 (0.84)mmol/L (P<0.001) on the plant sterol diet. The 20% decrease on the plant sterol diet was significantly greater (P<0.001) than the 12% decrease on the carbohydrate diet. Relative to the NZ diet, mean (95% CI) plasma high-density lipoprotein cholesterol concentration changed by -0.11 (-0.16, -0.06)mmol/L on the CHO diet but was not different at the end of the PS diet, -0.03 (-0.09, 0.02). CONCLUSION: Including a plant sterol-enriched fat spread in a cholesterol-lowering diet produces a more favourable plasma lipid profile than the same diet made lower in total and saturated fat by replacing the spread with carbohydrate-rich foods.  相似文献   
105.
The prevalence and characteristics of silent myocardial ischemia as detected by 24-hour ambulatory electrocardiography ST-segment depression were prospectively assessed in 94 patients examined early (1 to 3 months) and 184 patients examined late (12 months) after coronary artery bypass grafting (CABG), and followed for a mean of 48 +/- 11 (range 4 to 62) months. The relation of ambulatory electrocardiographic silent ischemia to evidence of completeness of revascularization as defined by cardiac angiography performed 1 and 12 months after CABG, and to prognosis by follow-up of adverse clinical events was analyzed. Silent ischemia was detected early in 20% (19 of 94) and late in 27% (50 of 184) of patients, and showed a mean frequency of episodes ranging from 6 to 10 episodes/24 hours with a mean duration ranging from 15 to 23 minutes. The circadian distribution of episodes disclosed a significant peak of ischemic activity during the period of 6 A.M. to noon and a secondary peak between 6 P.M. and midnight (p less than 0.01 and p less than 0.001, respectively). Silent ischemia was not found by univariate analysis to be associated with graft or anastomotic site occlusions, low graft flow rates, grafted arteries with significant distal residual stenoses or ungrafted stenotic native coronary arteries. Kaplan-Meier analysis of time to cardiac event showed that silent ischemia was not predictive of an adverse clinical event in the early years after CABG. Cox regression analysis of 30 covariates only disclosed age (relative risk 1.06 [95% confidence interval, 1.01 to 2.94]) as having an effect on time to adverse clinical event.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
106.
Background: Although patients with diabetes are frequently affected by periodontitis, only a few investigations have focused on gingivitis in this at‐risk population. This randomized placebo‐controlled clinical trial compared the response to a gingivitis treatment protocol that combined mechanical procedures and daily use of an essential oil (EO) mouthrinse between patients with and without diabetes. Methods: The whole‐mouth periodontal probing depth (PD), gingival index (GI), and plaque index (PI) were monitored in gingivitis cases among systemically healthy patients (n = 60) or those with diabetes (n = 60) at baseline and 3 months after treatment. Levels of Porphyromonas gingivalis, Tannerella forsythia, Aggregatibacter actinomycetemcomitans, and total bacterial load were determined by a real‐time polymerase chain reaction in intrasulci plaque samples. The volume of gingival crevicular fluid (GCF) was quantified, and interleukin‐1β (IL‐1β) levels were determined in GCF samples. After a full‐mouth ultrasonic debridement, patients were randomly assigned to an EO or a placebo rinse for 90 days (40 mL/day). The data were analyzed through repeated‐measures analysis of variance and multiple comparisons Tukey tests (P <0.05). Results: GI was more severe in the diabetes group. Diabetes impaired GI and reduced GCF volume. PD, bacterial levels, and IL‐1β improved similarly in both systemic conditions. The adjunctive use of EO provided greater reductions of PI, GI, total bacterial load, T. forsythia, A. actinomycetemcomitans, and GCF volume. Conclusions: Response to gingivitis treatment in patients with diabetes can slightly differ from that in patients without diabetes. Daily use of an EO mouthrinse after ultrasonic debridement benefited patients with and without diabetes.  相似文献   
107.
Background: There are few studies on periodontal status related to microbiologic and immunologic profiles among individuals not or occasionally using alcohol and those with alcohol dependence. The aim of this study is to determine the effect of alcohol consumption on the levels of subgingival periodontal pathogens and proinflammatory cytokines (interleukin [IL]‐1β and tumor necrosis factor [TNF]‐α) in the gingival fluid among individuals with and without periodontitis. Methods: This observational analytic study includes 88 volunteers allocated in four groups (n = 22): individuals with alcohol dependence and periodontitis (ADP), individuals with alcohol dependence and without periodontitis (ADNP), individuals not or occasionally using alcohol with periodontitis (NAP), and individuals not or occasionally using alcohol without periodontitis (NANP). Levels of Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Eikenella corrodens, and Fusobacterium nucleatum were determined by real‐time polymerase chain reaction on the basis of the subgingival biofilm, and IL‐1β and TNF‐α were quantified by enzyme‐linked immunosorbent assay in gingival fluid samples. Results: Individuals with alcohol dependence showed worse periodontal status and higher levels of P. intermedia, E. corrodens, F. nucleatum, and IL‐1β than non‐users. No significant correlations between TNF‐α and bacterial levels were observed. However, in the ADP group, higher levels of E. corrodens were correlated with higher levels of IL‐1β. Conclusion: A negative influence of alcohol consumption was observed on clinical and microbiologic periodontal parameters, as well as a slight influence on immunologic parameters, signaling the need for additional studies.  相似文献   
108.
Background : Nitrite is a biologic factor relevant to oral and systemic homeostasis. Through an oral bacteria reduction process, it was suggested that periodontal therapy and chlorhexidine (CHX) rinse could affect nitrite levels, leading to negative effects, such as an increase in blood pressure. This 6‐month randomized clinical trial evaluated the effects of periodontal therapeutic protocols on salivary nitrite and its relation to subgingival bacteria. Methods: One hundred patients with periodontitis were allocated randomly to debridement procedures in four weekly sections (quadrant scaling [QS]) or within 24 hours (full‐mouth scaling [FMS]) in conjunction with a 60‐day CHX (QS + CHX and FMS + CHX), placebo (QS + placebo and FMS + placebo), or no mouthrinse (QS + none and FMS + none) use. Real‐time polymerase chain reaction determined total bacterial, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Streptococcus oralis, and Actinomyces naeslundii levels. Salivary nitrite concentration was determined with Griess reagent. Data were analyzed statistically at baseline and 3 and 6 months by analysis of variance, Kruskal–Wallis, Mann–Whitney U, and Spearman correlation tests (P <0.05). Results: Nitrite concentrations did not tend to change over time. Regarding CHX use, there was a negative correlation between nitrite and total bacterial load at 6 months (FMS + CHX) and one positive correlation between P. gingivalis and nitrite at baseline (QS + CHX). Independently of rinse type, in the FMS group, nitrite correlated negatively with several microbial parameters and also with a higher percentage of deep periodontal pockets. Conclusions: The relationship between nitrite and bacterial levels appears weak. Short‐term scaling exhibited a greater influence on nitrite concentrations then long‐term CHX use.  相似文献   
109.
BACKGROUND & AIMS: "Academic detailing" is an effective strategy for promoting the use of screening sigmoidoscopy by primary care physicians. The primary objectives of this study were to determine whether the sustained presence of an "outside" university-based gastroenterologist performing on-site screening sigmoidoscopy promoted long-term utilization and whether the provision for on-site sigmoidoscopy was an effective venue for training primary care endoscopists. METHODS: Nine urban community health centers, including 4 intervention and 5 control sites, participated in a nonrandomized controlled trial conducted over 3 years. RESULTS: By the end of year 3, overall self-reported use of screening sigmoidoscopy increased by 61% for the intervention group vs. only 25% for the comparison group (P = 0.001). Ninety-seven percent of those reporting compliance referred 1 or more asymptomatic average-risk patients for screening examinations. Only 2 of 83 (2.4%) eligible providers completed on-site training and continued performing screening examinations independently. The major barriers to participation included lack of interest, lack of time to learn or perform sigmoidoscopy, concerns about technical competence, and lack of need because of on-site availability. CONCLUSIONS: Maintenance of on-site screening sigmoidoscopy services performed by an outside gastroenterologist promotes long-term utilization but fails as venue for training primary care endoscopists. Alternative strategies for expanding capacity are needed.  相似文献   
110.
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