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1.
Objective: To examine (i) the associations between physical activity dimensions, cardiorespiratory fitness and body composition and, (ii) the associations between physical activity dimensions, cardiorespiratory fitness, body composition and biomarkers of cardiometabolic health in persons with spinal cord injury (SCI).

Methods: A cross-sectional prospective cohort study with 7-day follow-up was conducted. Body composition, cardiorespiratory fitness and biomarkers of cardiometabolic health were measured in thirty-three participants with SCI (> 1 year post injury). Physical activity dimensions were objectively assessed over 7-days.

Results: Activity energy expenditure (r =.43), physical activity level (r =.39), and moderate-to-vigorous physical activity (MVPA) (r =.48) were significantly (P < 0.001) associated with absolute (L/min) peak oxygen uptake (?O2 peak). ?O2 peak was significantly higher in persons performing ≥150 MVPA minutes/week compared to <40 minutes/week (P?=?0.003). Individual physical activity dimensions were not significantly associated with biomarkers of cardiometabolic health. However, body composition characteristics (BMI, waist and hip circumference) showed significant (P < 0.04), moderate (r >.30) associations with parameters of metabolic regulation, lipid profiles and inflammatory biomarkers. Relative ?O2 peak (ml/kg/min) was moderately associated with only insulin sensitivity (r?=?0.37, P?=?0.03).

Conclusions: Physical activity dimensions are associated with cardiorespiratory fitness; however, stronger and more consistent associations suggest that poor cardiometabolic health is associated with higher body fat content. Given these findings, the regulation of energy balance should be an important consideration for researchers and clinicians looking to improve cardiometabolic health in persons with SCI.  相似文献   

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The sodium, potassium and creatinine contents of three non-consecutive 24-h urine samples collected by 34 selected adult individuals (10 m; 24 f) living in Cork City were determined. The pooled mean 24-h excretion of sodium and potassium in collections adjudged to be complete were 152 mmol and 78 mmol, respectively. There was no significant difference between group average weekday and weekend-day excretion of Na or K, for either males or females. This suggests that weekend 24-h urinary collections, which most subjects find more convenient, are suitable for studies of sodium and potassium intakes of groups. The ratios of intra- to inter-individual variation for 24-h urinary sodium were 1.4 and 2.1 for males and females, respectively. The corresponding ratios for 24-h urinary potassium were 6.6 for males and 4.9 for females. These ratios indicated that there were large individual day-to-day variations in urinary sodium and potassium excretion in this group. It was estimated that a sample size of 35-60 individuals would be required to estimate group mean sodium and potassium intakes by means of single 24-h urine collections.  相似文献   
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OBJECTIVE: To identify the possible contribution of electromyogram (EMG) to scalp electroencephalogram (EEG) rhythms at rest and induced or evoked by cognitive tasks. METHODS: Scalp EEG recordings were made on two subjects in presence and absence of complete neuromuscular blockade, sparing the dominant arm. The subjects undertook cognitive tasks in both states to allow direct comparison of electrical recordings. RESULTS: EEG rhythms in the paralysed state differed significantly compared with the unparalysed state, with 10- to 200-fold differences in the power of frequencies above 20 Hz during paralysis. CONCLUSIONS: Most of the scalp EEG recording above 20 Hz is of EMG origin. Previous studies measuring gamma EEG need to be re-evaluated. SIGNIFICANCE: This has a significant impact on measurements of gamma rhythms from the scalp EEG in unparalysed humans. It is to be hoped that signal separation methods will be able to rectify this situation.  相似文献   
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Knee anterior cruciate ligament reconstructive surgery has significantly evolved and now includes the option of using an allograft. This has resulted in numerous studies evaluating the advantages and disadvantages of allografts. The purpose of this literature review is to evaluate this research and present important findings to allow the selection of the most appropriate graft source when considering allograft versus autograft reconstruction.  相似文献   
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To ascertain the potential role of reactive oxygen metabolites in the pathophysiology of obstructive uropathy, we examined the effect of probucol, an antioxidant agent, on renal function in normal rats and rats with unilateral release of bilateral ureteral obstruction (BUO) of 24 hours duration. Rats were fed either a standard diet or a standard diet containing one percent probucol for two weeks prior to study. Probucol lowered serum cholesterol in both normal and BUO rats. Probucol did not significantly affect renal function in normal rats. BUO rats given probucol had greater inulin and PAH clearances at three to five hours and three days following release of BUO than rats with BUO not given probucol. Kidneys from obstructed rats had higher levels of malondialdehyde, an index of lipid peroxidation, a greater number of leukocytes in the cortex, decreased levels of reduced glutathione and increased levels of oxidized glutathione. Renal cortex from obstructed rats treated with probucol had significantly higher levels of reduced glutathione than kidneys of obstructed rats not given probucol. A decrease in cholesterol, using another lipid-lowering agent, lovastatin, did not modify renal function in rats with BUO. The data can be interpreted to indicate a role for reactive oxygen species in the pathophysiology of obstructive nephropathy. The improved renal function seen in probucol-treated rats with BUO may be due to an effect of this agent in affecting accumulation of reactive oxygen metabolites and/or decreasing the number of leukocytes infiltrating the renal cortex.  相似文献   
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The purpose of this study was to examine individuals 5 years after ACL reconstruction and analyze changes involving strength, stability, function, and sports activities. Nineteen males and six females, mean age = 31.4 +/- 7.31 years, participated in this study. Fifteen subjects had received extraarticular and ten subjects had received intraarticular ACL reconstructions. Subjects completed a 100 point subjective functional activity questionnaire and a sports participation survey. Knee ligament stability was assessed during an objective knee examination. Isokinetic quadriceps and hamstring muscle strength were tested at 240 and 120 deg/sec using the Cybex II dynamometer. Anterolateral rotatory instability and positive Lachman were elicited on the operated leg for 80% of the subjects. No significant relationship was found between objective instability and the functional activity score. For the intraarticular group, a significant correlation (P less than 0.05) was found between increased quadriceps and hamstring strength on the operated leg and return to functional activities. Subjects' functional activity score was positively correlated (P less than 0.001) with their ability to participate in sports. Subjects participating in sports involving cutting and twisting motions were less successful in returning to their preinjury participation levels and reported more subjective complaints of pain, swelling, and/or instability. These results indicate that long-term progressive rehabilitation emphasizing increased quadriceps and hamstring strength to approximate the nonoperated leg may enhance successful return to functional and sports activities after ACL reconstruction.  相似文献   
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Cell mediated immunity (CMI) was assessed by the ImmuKnow assay in 12 patients after kidney transplantation, who presented with viral infection. Treatment included lowering of immunosuppression in all cases and antiviral treatment if indicated. The assay was repeated during the follow up. The ImmuKnow assay at time of presentation of viral infections was 56.8 ± 58.2 (range 3–178; median 22) ATP ng/ml. With the clearance of viral infection and lowering of immunosuppression, the assay showed an increase in the level of CMI at 194.5 ± 118.9 (range 53–409; median 150) ATP ng/ml. There was viral clearance or stabilization in all cases and there was no incidence of allograft rejection. The ImmuKnow assay of CMI can be used to titrate initial immunosuppression reduction and its subsequent increase, in patients with viral infection after transplantation.  相似文献   
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Mean time parameters provide a new approach to plasma pharmacokinetics of radiolabeled Mabs that may show important patient differences affecting diagnosis or treatment. We determined mean time pharmacokinetic parameters for 11 patients entered in a Phase I/II clinical trial for detection of colorectal cancer. Patients were administered 0.5-2 mg of B72.3 anti-TAG-72 radiolabeled with 3.5-5 mCi of 111In, plasma activity was measured over time. Mean time pharmacokinetic parameters were (mean +/- s.e.m.): mean residence time; body (MRTB) 88.9 +/- 7.2 hr, central (MRTC) 73.8 +/- 6.0 hr; mean transit time, central (MTTC) 41.1 +/- 9.0 hr; mean residence time, periphery (MRTP) 15.1 +/- 3.4 hr; intrinsic mean residence time, periphery (IMPTP) 39.0 +/- 7.6 hr; mean transit time, periphery (MTTP) 24.0 +/- 6.7 hr; probability of distribution (PRD) 50% +/- 10%; and n compartmental cycles of 4.54 +/- 2.3 times. In patients with increased circulating specific TAG-72 antigen, MRTC greater than MTTC and n much greater than 1. In patients without specific antigen, MRTC approximately equal to MTTC and n much less than 1. Pharmacokinetic studies may identify patients who do not have the tumor produced target antigen for the specific Mab and may provide an opportunity to select another specific Mab with an increased chance for successful diagnosis or treatment.  相似文献   
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