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BACKGROUND: Strain rate (SR) imaging (SRI) is a tissue Doppler-based method of regional myocardial deformation imaging. The aim of this study was to see whether SRI could quantify changes in myocardial mechanical function after an acute myocardial infarction, and to follow the time course of these changes. METHODS: In all, 26 consecutive patients with first-time acute myocardial infarctions were examined on days 1, 7, and 90. Segments were analyzed with SRI and wall-motion score. RESULTS: Peak systolic SR in infarcted segments increased significantly in magnitude from day 1 to 7 (-0.45 to -0.68 s -1 , P < .001), but not after day 7. The deformation rate in border zone segments also increased significantly from day 1 to 7 (-0.8 to -0.95 s -1 , P < .05), with no further significant changes at 3 months. In normal segments, peak systolic SR decreased in magnitude during the first week. Systolic strain showed similar results as peak systolic SR. CONCLUSION: SRI can demonstrate small changes in deformation rate from midinfarct through the infarct and border zone to normal myocardium. It can also show changes over time, probably as a result of recovery of stunned myocardium.  相似文献   
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Thylakoids are membranes isolated from plant chloroplasts which have previously been shown to inhibit pancreatic lipase/colipase catalysed hydrolysis of fat in vitro and induce short‐term satiety in vivo. The purpose of the present study was to examine if dietary supplementation of thylakoids could affect food intake and body weight during long‐term feeding in mice. Female apolipoprotein E‐deficient mice were fed a high‐fat diet containing 41% of fat by energy with and without thylakoids for 100 days. Mice fed the thylakoid‐enriched diet had suppressed food intake, body weight gain and body fat compared with the high‐fat fed control mice. Reduced serum glucose, serum triglyceride and serum free fatty acid levels were found in the thylakoid‐treated animals. The satiety hormone cholecystokinin was elevated, suggesting this hormone mediates satiety. Leptin levels were reduced, reflecting a decreased fat mass. There was no sign of desensitization in the animals treated with thylakoids. The results suggest that thylakoids are useful to suppress appetite and body weight gain when supplemented to a high‐fat food during long‐term feeding. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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This cross-sectional analysis evaluated the effect of age and body mass index (BMI) on Three-Factor Eating Questionnaire scores in males. Subjects (n = 60) were recruited according to BMI status. Each completed the 51-item Three-Factor Eating Questionnaire. The group was split at the median age to produce a “younger” and “older” group for statistical analysis. A 2-way between-groups analysis of variance revealed a significant main effect of BMI on disinhibition (P = .003) and hunger (P = .041) with higher levels found in overweight males compared to healthy-weight counterparts. A significant main effect of age on hunger (P = .046) demonstrated older males were less susceptible to hunger than younger males. These insights provide a better understanding of eating behavior across the male life cycle and may assist health professionals to better guide men in weight management in the light of rising overweight/obesity.  相似文献   
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We report our experience with elastic stable intramedullary titanium nailing (ESIN) of femoral shaft fractures in children. From 1998 to 2001, we treated 31 children (20 boys), median age 6 (4-11) years, with ESIN for 29 closed and 2 grade I open femoral shaft fractures. We reviewed 30 children clinically after median 1.5 (1-3) years. Their median hospital stay was 6 (2-20) days. All fractures were radiographically united at a median of 7 (5-9) weeks. The nails were removed in 29 children after a median of 22 (6-38) weeks postoperatively. At follow-up, we found a leg-length discrepancy up to 1 cm in 6 children and 10 degrees of internal rotational deformity in 1 child. No angular deformity had occurred. Elastic stable intramedullary nailing seems to be a safe method for the treatment of femoral shaft fractures in children between 4 and 11 years of age.  相似文献   
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OBJECTIVE: The purpose of this study was to examine the effect of optimal seated positioning in individually fitted furniture versus suboptimal seated positioning in standard classroom furniture on typical 6- and 7-year-old children's object manipulation skills as measured by the In-hand Manipulation Test (IMT). METHOD: An experimental research design was used to compare IMT performance of two groups of 20 children. One group was positioned in standard, too-large classroom furniture that did not support an optimal seated position, and one group was positioned optimally in furniture fitted to each child for tabletop activities, which allowed for hip flexion to 90 degrees, and foot placement on the floor, and the table to be at flexed elbow height. RESULTS: Independent groups' t tests indicated that children who were optimally positioned performed significantly better (t = -2.77, df = 38, p < .01) than children who were tested in the too-large standard classroom furniture. The difference between groups was greater on the more difficult object manipulation items (t = -3.29, df = 38, p = .001) than on the easier items (t = -1.38, df = 38, p = .08). Age and gender may have differentially affected the results. CONCLUSION: The study's results suggest that the fit of furniture relative to the child's size may have a significant impact on a young, typical child's object manipulation skills. Complex hand skills, such as those involving in-hand manipulation with stabilization, appear to be more affected by the quality of the child's seated position than are simpler, more well-established skills. Findings suggest that test administrators should strive to test young children in the most optimal seated position possible, particularly when the test involves complex hand skills. Further study is needed to assess the impact of the fit of furniture on hand skills in children with disabilities and on children's performance of other tasks.  相似文献   
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A new computer-based collision technique for direct measurement of the human motor nerve conduction velocity distribution is described. In contrast to previous collision techniques, the test muscle response is progressively cancelled to a null using an arrangement of proximal and distal stimuli which eliminates distortion of the test response caused by transient changes in nerve and muscle fibre conduction. The increased sensitivity of this new technique permits accurate measurement of the slowest 1% of alpha motor nerve fibres. We have used our modified collision technique to determine motor nerve conduction velocity distributions for the median nerve in 20 normal subjects aged between 19 and 59 (mean 35) years. 150% maximal stimulus intensities were used, with a controlled limb temperature of 35 degrees C. Group mean velocities (+/- S.D.) for the fastest (95%), mean (50%) and slowest (5% and 1%) motor fibres were 59.1 +/- 3.0, 56.9 +/- 2.9, 52.7 +/- 3.1 and 51.2 +/- 3.7 m/sec respectively. Data are also presented for the ulnar and peroneal nerves.  相似文献   
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