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51.
This study investigated the association of blood pressure with blood oxidative stress-related parameters in normotensive and hypertensive subjects. A cross-sectional design was applied to 31 hypertensive patients and 35 healthy normotensive subjects. All subjects were men between the ages of 35 and 60 years. Exclusion criteria were obesity, dyslipidemia, diabetes mellitus, smoking and current use of any medication. All patients underwent 24-h ambulatory blood pressure monitoring and sampling of blood and urine. Antioxidant enzymes activity, reduced/oxidized glutathione ratio (GSH/GSSG), and lipid peroxidation (malondialdehyde) were determined in erythrocytes. Parameters measured in the plasma of test subjects were plasma antioxidant status, lipid peroxidation (8-isoprostane), plasma vitamin C and E, and the blood pressure modulators renin, aldosterone, endothelin-1 and homocysteine. Daytime systolic and diastolic blood pressures of hypertensives were negatively correlated with plasma antioxidant capacity (r=-0.46, p<0.009 and r=-0.48, p<0.007), plasma vitamin C levels (r=-0.53, p<0.003 and r=-0.44, p<0.02), erythrocyte activity of antioxidant enzymes, and erythrocyte GSH/GSSG ratio, with hypertensives showing higher levels of oxidative stress. Blood pressures showed a positive correlation with both plasma and urine 8-isoprostane. Neither plasma vitamin E nor the assessed blood pressure modulator levels showed significant differences between the groups or correlation with blood pressures. These findings demonstrate a strong association between blood pressure and some oxidative stress-related parameters and suggest a possible role of oxidative stress in the pathophysiology of essential hypertension.  相似文献   
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We sought whether microdamage could rise in postmenopausal osteoporotic women on long-term bisphosphonates, as suggested by recent animal studies. We found few microcracks in iliac bone biopsies, despite a marked reduction in bone turnover. INTRODUCTION: Animal studies suggest that bisphosphonates (BPs) could increase microdamage frequency in a dose-dependent manner, caused by excessively suppressed bone turnover. However, there is limited data in humans receiving BP therapeutic doses for >3 yr. MATERIALS AND METHODS: We measured microcrack frequency and histomorphometry parameters on transiliac bone biopsies in 50 postmenopausal osteoporotic women (mean age = 68 yr) who had received BP therapy (3 on intravenous pamidronate, 37 on oral alendronate, and 10 on oral risedronate) for at least 3 yr (mean treatment duration = 6.5 yr). We compared these results with transiliac bone biopsies obtained from 12 cadavers. We used bulk staining with green calcein as a fluorochrome. The microcracks were quantified in three 100-microm-thick sections using optic microscopy and were confirmed by laser confocal microscopy. Microcrack frequency (number of microcracks/mm2 of bone tissue) was compared between treated women and controls using nonparametric tests. We also explored predictors of microcrack frequency, including age, duration of BP therapy, and activation frequency. RESULTS: Among treated women, cancellous bone microcrack frequency was low (mean, 0.13 microcracks/mm2) and did not differ significantly from that observed in controls (0.05 microcracks/mm2; p = 0.59). Of note, 54% of the treated women and 58% of the controls had no observable microcracks. There was no association between microcrack frequency and the duration of BP therapy (for microcracks/mm2 and duration, Spearman r = 0.04, p = 0.80) and between patients' ages and the number of microcracks (Spearman r = -0.09, p = 0.61). Although bone remodeling parameters were suppressed in treated women, we found no relationship between microcrack density and activation frequency (Spearman r = -0.003, p = 0.99). Also, microcrack frequency was not increased in women with prevalent vertebral fracture compared with those without fractures. CONCLUSIONS: Among postmenopausal osteoporotic women on long-term BPs, microcrack frequency in the iliac bone is low, despite a marked reduction of bone turnover.  相似文献   
54.
The aim of this study was to evaluate the effectiveness of incremental and maximum bite advancement during treatment of Class II Division 1 malocclusion with the Twin-block appliance in the permanent dentition. It was performed at 3 district general hospitals in the United Kingdom with 4 operators. Two hundred three patients, 10-14 years old, were randomized. Control patients had the initial bite taken edge-to-edge for appliance construction with a standard Twin-block. Experimental patients had 2 mm initial bite advancement and subsequent 2 mm advancements at 6 weekly intervals with a Twin-block appliance incorporating advancement screws. Data were collected at the start and the finish of Twin-block treatment. The use of incremental advancement of the Twin-block did not confer any advantages in terms of process and outcome of the treatment. However, patient compliance was influenced by operator and patient age. The duration of treatment was influenced by operator and initial overjet. Incremental bite advancement produced no advantages over maximum advancement.  相似文献   
55.
OBJECTIVE: To assess the therapeutic effect of the extent of lymph node dissection performed in patients with a stage pI non-small-cell lung cancer (NSCLC). METHODS: We analysed data on 465 patients with stage I NSCLC who were treated with surgical resection and some form of lymph node sampling. The median number of lymph node sampled was 10 and the median number of ipsilateral mediastinal lymph node stations sampled was two. We chose to define a procedure that harvested 10 or more lymph nodes and sampled two or more ipsilateral mediastinal stations as a lymphadenectomy, by contrast with sampling when one or both criteria were not satisfied. The effect of the surgical techniques: lymph node sampling (LS; n=207) vs. lymphadenectomy (LA; n=258) on 30-day mortality and overall survival were investigated. RESULTS: A total of 6244 lymph nodes was examined, including 4306 mediastinal lymph nodes. The mean (+/-SD) numbers of removed lymph nodes were 7+/-6.1 per patient following LS vs.18.6+/-9.3 following LA (P=0.001). An average mean of 1+/-0.90 mediastinal lymph node station per patient was sampled following LS vs. 2.7+/-0.8 following LA (P<10(-6)). Overall 30-day mortality rates were 2.4 and 3.1%, respectively. LA was disclosed as a favourable prognosticator at multivariate analysis (Hazard Risk: 1.43; 95% Confidence Interval: 1.00-2.04; P=0.048), together with younger patient age, absence of blood vessels invasion, and smaller tumour size. CONCLUSIONS: Importance of lymph node dissection affects patients outcome, while it does not enhance the operative mortality. A minimum of 10 lymph nodes assessed, and two mediastinal stations sampled are suggested as possible pragmatic markers of the quality of lymphadenectomy.  相似文献   
56.
Aim: The purpose of this project was to operationalize and apply a previously identified set of performance measures designed to evaluate services for those experiencing a first episode of a schizophrenia spectrum disorder. Methods: Operational definitions were developed for previously identified measures through an iterative process of discussions between clinical experts and health‐care evaluators. Data were collected from existing sources including corporate databases, clinical databases and chart review. Results: Definitions were developed for 44 measures covering seven of eight domains recommended for service level evaluation by the Canadian Institute for Health Information domains. Forty measures could be calculated. Conclusions: The measures represent a comprehensive set of performance measures suitable for the evaluation of services for people with a first‐episode psychosis. The measures could be used by other services in order to establish standards and norms for routine clinical practice.  相似文献   
57.
OBJECTIVE: Dilation of aortic annulus, sinuses of Valsalva, and sinotubular junction (STJ) diameters are the characteristic lesions of aortic root aneurysm. The remodeling technique reduces STJ diameter and creates three neosinuses of Valsalva. Alternatively, the reimplantation technique reduces both annulus and STJ diameters to the detriment of aortic root dynamics. Although the remodeling technique is recognized as the most physiological valve-sparing procedure, aortic annulus dilation may jeopardize its results. A standardized approach that combines an external subvalvular aortic prosthetic ring annuloplasty with the remodeling technique is suggested. METHODS: Eighty-three patients underwent an elective aortic root remodeling procedure, either isolated (group 1, n=34) or combined with an external subvalvular aortic prosthetic ring annuloplasty (group 2, n=49). Preoperative aortic regurgitation was 1.59+/-1.1 (group 1) and 1.97+/-1.3 (group 2) (NS). The aortic annulus was more dilated in group 2 than in group 1 (27+/-2.77 mm vs 26.4+/-2.3 mm, p<0.01). Residual aortic regurgitation > or =grade II was the conversion criteria for aortic valve replacement. RESULTS: Operative mortality was 3.6% (n=3). Intraoperative conversion for valve replacement was 32.7% in group 1 (n=11) versus 4.2% in group 2 (n=2) (p<0.001). In group 1, preoperative annulus diameter was larger for converted than for valve-spared patients (27.6+/-1.7 mm vs 25.2+/-1.5 mm, p<0.02). In group 2, implanted aortic ring significantly reduced annulus diameter (20.6+/-1.8 mm) without significant aortic valve gradient (8.3+/-3 mmHg). Follow-up was 17.2+/-13.4 months (group 1) and 10.41+/-7.95 months (group 2). Reoperation for recurrent aortic regurgitation was 13% in group 1 (n=3) versus 4.2% in group 2 (n=2). Echocardiographic follow-up found residual aortic regurgitation < or =grade I in 17 patients in group 1 (90%) versus 43 patients in group 2 (95.5%) and of grade II in two patients in group 1 (10%) and two patients in group 2 (4.5%). CONCLUSION: The addition of external aortic prosthetic ring annuloplasty improves the remodeling technique's operative reproducibility and short-term results. Therefore, its use as a systematical adjunct to the remodeling procedure is suggested. However, further long-term evaluation comparing this valve-sparing procedure to composite graft replacement should define the best surgical strategy for aortic root aneurysm.  相似文献   
58.
OBJECTIVE: The purpose of this study was to investigate the effects of therapy balls as seating on in-seat behavior and legible word productivity of students with attention deficit hyperactivity disorder (ADHD). Additionally, social validity was assessed to evaluate teacher and student opinions regarding the intervention. METHOD: A single subject, A-B-A-B interrupted time series design was employed across 3 students (2 males, 1 female) with ADHD. The study was conducted in a 4th grade inclusive classroom during daily language arts. During phases 1 and 3, the 3 participants and all other class members sat on chairs (in-seat on chair); during phases 2 and 4, everyone sat on therapy balls (in-seat on ball). Dependent variables were in-seat behavior and legible word productivity. Data were graphed and visually analyzed for differences between phases. RESULTS: Results demonstrated increases in in-seat behavior and legible word productivity for the students with ADHD when seated on therapy balls. Social validity findings indicated that generally the teacher and students preferred therapy balls. CONCLUSION: This study provides evidence that use of therapy balls for students with ADHD may facilitate in-seat behavior and legible word productivity.  相似文献   
59.
A 68-year-old man developed right homonymous hemianopic paracentral scotomas from acute infarction of the left extrastriate area. He was studied over the ensuing 12 months with visual fields, conventional MRI, functional MRI (fMRI), and diffusion tensor imaging (DTI). As the visual field defect became smaller, fMRI demonstrated progressively larger areas of cortical activation. DTI initially showed that the lesioned posterior optic radiations were completely interrupted. This interruption lessened in time and had disappeared by one year after onset. fMRI and DTI are innovative measures to follow functional and structural recovery in the central nervous system. This is the first reported application of these imaging techniques to acute cerebral visual field disorders.  相似文献   
60.
This study evaluated the effectiveness of early orthodontic treatment with the Twin-block appliance for the developing Class II Division 1 malocclusion. This multicenter trial was carried out in the United Kingdom. A total of 174 children, aged 8 to 10 years old, with Class II Division 1 malocclusion were randomly allocated to receive treatment with a Twin-block appliance or to an untreated, control group. Data were collected at the start of the study and 15 months later. Results showed that early treatment with Twin-block appliances resulted in reduction of overjet, correction of molar relationships, and reduction in severity of malocclusion. Most of this correction was due to dentoalveolar change, but some was due to favorable skeletal change. Early treatment with the Twin-block appliance is effective in reducing overjet and severity of malocclusion. The small change in the skeletal relationship might not be considered clinically significant.  相似文献   
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