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41.
The concentration of glycine (Gly) was measured in gray matter (GM) and white matter (WM) in the human brain using single‐voxel localized 1H MRS at 7 T. A point‐resolved spectroscopy sequence with echo time = 150 ms was used for measuring Gly levels in various regions of the frontal and occipital lobes in 11 healthy volunteers and one subject with a glioblastoma. The point‐resolved spectroscopy spectra were analyzed with LCModel using basis functions generated from density matrix simulations that included the effects of volume localized radio‐frequency and gradient pulses. The fraction of GM and white matter within the voxels was obtained from T1‐weighted image segmentation. The metabolite concentrations within the voxels, estimated with respect to the GM + WM water concentrations, were fitted to a linear function of fractional GM content. The Gly concentrations in pure GM and white matter were estimated to be 1.1 and 0.1 mM, with 95% confidence intervals 1.0–1.2 and 0.0–0.2, respectively. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
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Computed tomography angiography (CTA) of the heart is a rapidly evolving application for comprehensive assessment of coronary arterial anatomy, myocardial function, perfusion, and myocardial viability. Thus, cardiac CTA is capable of retrieving the most critical information for guiding the management of patients with suspected coronary heart disease (CHD). Ongoing technologic advancements have allowed acquiring such information within minutes, at radiation doses that are lower than those from conventional computed tomography imaging or common nuclear imaging techniques. Cardiac CTA has positioned itself as an imaging modality that may be well suited to fulfill central needs of cardiovascular medicine. This article reviews the evidence for the clinical utility of cardiac CTA in patients with suspected CHD.  相似文献   
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Background:

Mortality due to pneumonia in children is more than any other illness. Limited data is available to predict mortality in children with pneumonia from central India.

Aim:

To study predictors of mortality in children aged 1-59 months hospitalised with severe and very severe pneumonia.

Materials and Methods:

Present study was observational longitudinal study that was done in a tertiary care hospital of central India. Two hundred and ninety children, aged 1-59 months, presented with severe and very severe pneumonia were enrolled in this study. Outcome and predictors of mortality were studied. Data was analysed with Chi-square test, univariate and multivariate regression analysis.

Results:

Out of 270 enrolled study subjects, maximum (108, 37.24%) were belonged to 1-6-months age group. Proportion of mortality was maximum (16, 64.00%) in that age group. Overall case fatality rate was 8.62%. Among significant variables, delayed hospital referral [adjusted odds ratio (OR)-52.09, 95% confidence interval (CI)- 6.74-402.39], incomplete immunisation (OR-12.28, 95% CI-2.15-69.93), severe malnutrition (Z score < −3) (OR-15.51, 95% CI- 2.04-117.83), refusal to feed (OR- 30.57, 95% CI- 2.47-378.26), and hypoglycaemia (OR- 6.98, 95% CI- 1.05-46.30) were found significant independently on multivariate regression analysis. Conclusion: Delayed hospital referral, incomplete immunisation, severe malnutrition, refusal to feed, and hypoglycaemia were independent predictors of mortality in children with severe and very severe pneumonia.  相似文献   
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Introduction

Pin site infection is the commonest complication of Ilizarov external fixation. The aim of the study was to examine if use of antiseptics was superior over control and further if daily dressing was superior to weekly dressing in regular pin site care in reducing the burden of pin site infection in Ilizarov fixators.

Patients and methods

A total of 114 patients (2363 pin sites) were randomised to receive regular pin site care alone (30 patients, 638 pin sites) or with additional application of povidone iodine (27 patients, 561 pin sites), silver sulfadiazine (27 patients, 570 pin sites) and chlorhexidine (30 patients, 594 pin sites). The pin tracts were sub-randomised to receive daily (1212 pin sites) or weekly (1151 pin sites) dressings. The primary outcome was pin site infection days rate across all four groups. The secondary outcomes were - mean duration to first episode of infection, differences between daily and weekly dressing groups, mean duration of antibiotic therapy and incidence of re-interventions and sequelae. We also recorded frequency of bacterial pathogens in all microbiological samples submitted. Block randomization using computer-generated random numbers was used. The assessor of outcome was blinded.

Results

All patients completed the study. Pin site infection rate days per 1000 pin site days observed was marginally less in chlorhexidine group, but was not statistically significant compared to other antiseptics and control group (Absolute value in control, povidone iodine, silver sulphadiazine and chlorhexidine groups were respectively 2.04?±?4.27, 2.04?±?3.65, 1.85?±?3.37, 1.37?±?2.35, p value 0.92). Daily dressing category showed slightly less pin site infection days rate within each group and overall, but this was also not statistically significant (1.56?±?3.99 versus 2.10?±?5.1, p value 0.35). There was no statistically significant difference among the groups with regard to other secondary outcomes. Methicillin Sensitive Staphylococcus aureus was the most common bacterial pathogen isolated.

Conclusion

Use of antiseptics does not offer any advantage in regular pin site care in Ilizarov external fixation and daily pin site care is not superior to weekly pin site care. Empirical therapy in early and low grade pin site infections must be targeted against Staphylococcus.  相似文献   
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