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[Purpose] This study investigated the intra-rater, inter-rater and test-retest reliability of the sideways step test (SST), its correlation with other indicators of stroke-specific impairment, and the cut-off count best discriminating subjects with stroke from their healthy counterparts. [Subjects and Methods] Forty-three subjects with chronic stroke and 41 healthy subjects older than 50 years participated in this study. The SST was administered along with the Fugl-Meyer motor assessment for the lower extremities (FMA-LE), the five-times sit to stand (5TSTS) test, the Berg Balance Scale (BBS), the movement velocity (MVL) by the limits of stability (LOS) test, the ten-metre walk (10mW) test, the timed “Up and Go” (TUG) test and the Activities-specific Balance Confidence (ABC) scale. [Results] The SST showed good to excellent intra-rater, inter-rater and test-retest reliability. The SST counts correlated with 5TSTS times, 10mW times, TUG times, and the FMA-LE and BBS scores. SST counts of 11 for the paretic leg and 14 for the non-paretic leg were found to distinguish the healthy adults from subjects with stroke. [Conclusion] The sideways step test is a reliable clinical test, which correlates with the functional strength, gait speed, and functional balance of people with chronic stroke.Key words: Balance, Stroke, Rehabilitation  相似文献   
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Background

Competitive sports training causes structural and conductive system changes manifesting by various electrocardiographic alterations. We undertook this study to assess the prevalence of abnormal ECG in trained Indian athletes and correlate it with the nature of sports training, that is endurance or strength training.

Methods

We evaluated a standard resting, lying 12 lead Electrocardiogram (ECG) in 66 actively training Indian athletes. Standard diagnostic criteria were used to define various morphological ECG abnormalities.

Results

33/66 (50%) of the athletes were undertaking endurance training while the other 33 (50%) were involved in a strength-training regimen. Overall 54/66 (81%) sportsmen had significant ECG changes. 68% of these changes were considered as normal training related features, while the remaining 32% were considered abnormal. There were seven common training related ECG changes–Sinus Bradycardia (21%), Sinus Arrhythmia (16%), 1st degree Atrioventricular Heart Block (6%), Type 1 2nd-degree Atrioventicular Heart Block (3%), Incomplete Right bundle branch block (RBBB) (24%), Early Repolarization (42%), Left Ventricular Hypertrophy (LVH) (14%); while three abnormal ECG changes--T-wave inversion (13%), RBBB(4%), Right ventricular hypertrophy (RVH) with strain (29%) were noted. Early repolarization (commonest change), sinus bradycardia, and incomplete RBBB were the commoner features noticed, with a significantly higher presence in the endurance trained athletes.

Conclusion

A high proportion of athletes undergoing competitive level sports training are likely to have abnormal ECG recordings. Majority of these are benign, and related to the physiological adaptation to the extreme levels of exertion. These changes are commoner during endurance training (running) than strength training (weightlifting).  相似文献   
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Background

Myocardial relaxation is impaired in almost all cases with left ventricular diastolic dysfunction (LVDD) and is a strong predictor of cardiovascular and all-cause mortality.

Objectives

This study investigated the feasibility of signal-processed surface electrocardiography (spECG) as a diagnostic tool for predicting the presence of abnormal cardiac muscle relaxation.

Methods

A total of 188 outpatients referred for coronary computed tomography (CT) angiography underwent an echocardiogram for assessment of LVDD. The use of 12-lead spECG for predicting myocardial relaxation abnormalities as identified using tissue Doppler echocardiography was validated with machine-learning approaches.

Results

A total of 188 subjects underwent diagnostic testing, with 133 (70%) showing abnormal myocardial relaxation on tissue Doppler imaging. A 12-lead spECG showed an area under the curve of 91% (95% confidence interval: 86% to 95%) for prediction of abnormal myocardial mechanical relaxation with a sensitivity and specificity of 80% and 84%, respectively. The spECG demonstrated more accurate diagnostic performance in individuals age ≥60 years as well as those with obesity or hypertension, compared with their respective counterparts. Prediction of low early diastolic relaxation velocity (e′) also correctly identified concomitant significant underlying coronary artery disease in 23 of 28 cases (82%). Furthermore, a superior integrated discrimination and net reclassification improvement was observed for spECG over clinical features and traditional ECG.

Conclusions

The spECG provides a robust prediction of abnormal myocardial relaxation. These data suggest a potential role for spECG as a novel screening strategy for identifying patients at risk for LVDD who would benefit undergoing echocardiographic evaluations.  相似文献   
95.
Assessment of aldehyde dehydrogenase in viable cells   总被引:3,自引:4,他引:3  
Cytosolic aldehyde dehydrogenase (ALDH), an enzyme responsible for oxidizing intracellular aldehydes, has an important role in ethanol, vitamin A, and cyclophosphamide metabolism. High expression of this enzyme in primitive stem cells from multiple tissues, including bone marrow and intestine, appears to be an important mechanism by which these cells are resistant to cyclophosphamide. However, although hematopoietic stem cells (HSC) express high levels of cytosolic ALDH, isolating viable HSC by their ALDH expression has not been possible because ALDH is an intracellular protein. We found that a fluorescent aldehyde, dansyl aminoacetaldehyde (DAAA), could be used in flow cytometry experiments to isolate viable mouse and human cells based on their ALDH content. The level of dansyl fluorescence exhibited by cells after incubation with DAAA paralleled cytosolic ALDH levels determined by Western blotting and the sensitivity of the cells to cyclophosphamide. Moreover, DAAA appeared to be a more sensitive means of assessing cytosolic ALDH levels than Western blotting. Bone marrow progenitors treated with DAAA proliferated normally. Furthermore, marrow cells expressing high levels of dansyl fluorescence after incubation with DAAA were enriched for hematopoietic progenitors. The ability to isolate viable cells that express high levels of cytosolic ALDH could be an important component of methodology for identifying and purifying HSC and for studying cyclophosphamide-resistant tumor cell populations.  相似文献   
96.
Kriegler  AB; Bernardo  D; Verschoor  SM 《Blood》1994,83(1):65-71
Corticosteroids have the ability to suppress the production of growth factors and cytokines and are thus implicated in the negative regulation of hematopoiesis. We have shown that the corticosteroids, prednisolone and dexamethasone, were able to effectively protect progenitor cells in four strains of mice against cell-cycle-specific antimetabolic chemotherapy agents. The highest levels of protection against 5-fluorouracil (FU; 200 mg/kg) were achieved when two or three intraperitoneal injections of dexamethasone were administered between - 7 and +3 hours at a dose of 7.5 mg/kg/injection (optimal dose) or by continuous infusion between -4 and +20 hours. This protective effect is manifested as an increase in the number of high proliferative potential colony-forming cells that survive in the bone marrow 3 days after treatment with FU from between 0.5% and 11% to between 10% and 34% of normal. The bone marrow progenitors and blood cell numbers return to normal from 3 to 5 days and 1 to 2 days earlier, respectively. Less dexamethasone than prednisolone is required to give an equivalent protective effect, which is consistent with their anti-inflammatory potency. These findings are further evidence of the negative regulatory role played by corticosteroids, and indicate that the treatment schedules of corticosteroids during cancer therapy need to be reexamined to obtain the maximum benefit from their use.  相似文献   
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