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31.
Kyle A Kemp Nancy Chan Brandi McCormack Kathleen Douglas-England 《Health services research》2015,50(4):982-997
ObjectiveTo identify factors associated with patients’ overall rating of inpatient hospital care.ConclusionsOur results are novel in the Canadian population. Several questions for future research have been generated, in addition to opportunities for quality improvement within our own organization. 相似文献
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Q. van Houtum D. Welting W.J.M. Gosselink D.W.J. Klomp C.S. Arteaga de Castro W.J.M. van der Kemp 《NMR in biomedicine》2019,32(12)
Phosphorus (31P) MRSI provides opportunities to monitor potential biomarkers. However, current applications of 31P MRS are generally restricted to relatively small volumes as small coils are used. Conventional surface coils require high energy adiabatic RF pulses to achieve flip angle homogeneity, leading to high specific absorption rates (SARs), and occupy space within the MRI bore. A birdcage coil behind the bore cover can potentially reduce the SAR constraints massively by use of conventional amplitude modulated pulses without sacrificing patient space. Here, we demonstrate that the integrated 31P birdcage coil setup with a high power RF amplifier at 7 T allows for low flip angle excitations with short repetition time (TR) for fast 3D chemical shift imaging (CSI) and 3D T1‐weighted CSI as well as high flip angle multi‐refocusing pulses, enabling multi‐echo CSI that can measure metabolite T2, over a large field of view in the body. B1+ calibration showed a variation of only 30% in maximum B1 in four volunteers. High signal‐to‐noise ratio (SNR) MRSI was obtained in the gluteal muscle using two fast in vivo 3D spectroscopic imaging protocols, with low and high flip angles, and with multi‐echo MRSI without exceeding SAR levels. In addition, full liver MRSI was achieved within SAR constraints. The integrated 31P body coil allowed for fast spectroscopic imaging and successful implementation of the multi‐echo method in the body at 7 T. Moreover, no additional enclosing hardware was needed for 31P excitation, paving the way to include larger subjects and more space for receiver arrays. The increase in possible number of RF excitations per scan time, due to the improved B1+ homogeneity and low SAR, allows SNR to be exchanged for spatial resolution in CSI and/or T1 weighting by simply manipulating TR and/or flip angle to detect and quantify ratios from different molecular species. 相似文献
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J. Löring W. J. M. van der Kemp S. Almujayyaz J. W. M. van Oorschot P. R. Luijten D. W. J. Klomp 《NMR in biomedicine》2016,29(6):709-720
Widespread use of ultrahigh‐field 31P MRSI in clinical studies is hindered by the limited field of view and non‐uniform radiofrequency (RF) field obtained from surface transceivers. The non‐uniform RF field necessitates the use of high specific absorption rate (SAR)‐demanding adiabatic RF pulses, limiting the signal‐to‐noise ratio (SNR) per unit of time. Here, we demonstrate the feasibility of using a body‐sized volume RF coil at 7 T, which enables uniform excitation and ultrafast power calibration by pick‐up probes. The performance of the body coil is examined by bench tests, and phantom and in vivo measurements in a 7‐T MRI scanner. The accuracy of power calibration with pick‐up probes is analyzed at a clinical 3‐T MR system with a close to identical 1H body coil integrated at the MR system. Finally, we demonstrate high‐quality three‐dimensional 31P MRSI of the human body at 7 T within 5 min of data acquisition that includes RF power calibration. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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We describe a case of an intelligent, artistic 50-year-old woman with schizoaffective disorder with a long history of delusional preoccupation with laterality and episodes of reported shifts in handedness. Investigations including dichotic listening and lateralised visual imagery tasks indicated unusual patterns of asymmetry. Executive functions were found to be intact, and EEG and CT scan were normal. Interview schedules revealed high scores for schizotypy, and no evidence of a dissociative disorder, whereas psychotic symptoms with mood lability were evident on mental status examination. The subject's preoccupations are illustrated with a selection of her artistic productions. The case is discussed in the context of reports of a relationship between schizophrenia and ambiguous handedness. A cognitive neuropsychiatric formulation briefly explores the possibility of alternative cerebral hemispheres affecting cognitive-perceptual operations. 相似文献
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J R Saltzman J A Kemp B B Golner M C Pedrosa G E Dallal R M Russell 《Journal of the American College of Nutrition》2013,32(6):584-591
To investigate the effects of hypochlorhydria and acidic drink ingestion on protein-bound vitamin B12 absorption in elderly subjects.Absorption of protein-bound vitamin B12 was examined in elderly normal subjects (n = 8), and in hypochlorhydric subjects due to omeprazole treatment (n = 8) or with atrophic gastritis (n = 3). Subjects underwent absorption tests of protein-bound vitamin B12 ingested with water, cranberry juice and 0.1 N hydrochloric acid.Protein-bound vitamin B12 absorption was lower in the omeprazole-treated group (0.50%) compared to the normal group (1.21%; p < 0.001). With cranberry juice ingestion, the omeprazole-treated group showed an increase in absorbed protein-bound vitamin B12 (p = 0.025). With dilute hydrochloric acid ingestion, there was a further increase in vitamin B12 absorption (p < 0.001).Omeprazole causes protein-bound vitamin B12 malabsorption, and ingestion of an acidic drink improves protein-bound vitamin B12 absorption. 相似文献
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