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41.
Over the last 30 years the Advanced Trauma Life Support (ATLS) course has become the most successful training program in the world for the early care of severely injured patients. It has shaped trauma care systems in many countries and is now on the verge of being introduced into Germany by the German Society of Trauma Surgery (DGU). However, after publication of the latest edition in 2004 there are rising concerns regarding the lack of multi-disciplinarity, out-dated contents and lack of adaptability to regional needs. This article questions the beneficial effect of ATLS on the advanced German trauma care system and concludes that ATLS is not likely to improve trauma care in Germany. 相似文献
42.
RoBbach M Jochimsen TH Herrmann KH Ros C Güllmar D Reichenbach JR 《Zeitschrift für medizinische Physik》2011,21(1):33-41
Echo planar imaging (EPI) in combination with PROPELLER allows high-resolution diffusion-weighted imaging. In this study, the image quality of short-axis and long-axis PROPELLER was compared and optimized using phantom and in vivo data. Furthermore, diffusion-weighted measurements using both sequences were compared with those of a reference sequence. It was found that the long-axis sequence provided better image quality, whereas the results of the diffusion weighted measurements were more accurate with the short-axis variant. and that the results of the diffusion weighted measurements of both sequences agreed well with those of the reference sequence. 相似文献
43.
The ability to noninvasively assess physiological changes in solid tumors is desired for its diagnostic and therapeutic potential. In this issue of JCI, Matsumoto and colleagues reveal their development and use of a novel imaging approach, combining pulsed electron paramagnetic resonance imaging (EPRI) with conventional MRI to image squamous cell carcinoma tumor-bearing mice (See the related article beginning on page 1965). This method provides coregistered images of oxygenation and blood volume/flow with the underlying anatomy and concentrations of metabolites such as lactate and choline. This technique, combining functional and anatomic imaging, shows immediate preclinical applicability in monitoring factors that control tumor hypoxia and metabolism and may have future clinical potential for monitoring tumor response to treatment. 相似文献
44.
The present paper describes the development of a model linking the optical density of a radiographic film to the applied dose. This model takes into account the kind of bremsstrahlung used in radiotherapy, and uses fewer parameters compared with the models developed so far. The measurements showed an influence of the field size on the model parameters. Monte Carlo simulations showed that different field sizes and depths in solid water can change the spectral distributions. The spectrum hardens with decreasing field size and increasing depth in phantom material. This has an influence on the model parameters. Nevertheless, the model can still be used to describe the relation between optical density and applied dose for films that are irradiated with fields of different size. A dose-rate dependence was not observed. The size and form of the fields used in calibration and application can therefore cause a systematic error in verification with film. 相似文献
45.
Graf J Mühlhoff C Doig GS Reinartz S Bode K Dujardin R Koch KC Roeb E Janssens U 《Critical care (London, England)》2008,12(4):R92
Introduction
The purpose of this study was to investigate the costs and health status outcomes of intensive care unit (ICU) admission in patients who present after sudden cardiac arrest with in-hospital or out-of-hospital cardiopulmonary resuscitation. 相似文献46.
Wolfgang M Schaefer Claudia S A Lipke Dirk Standke Harald P Kühl Bernd Nowak Hans-Juergen Kaiser Karl-Christian Koch Udalrich Buell 《Journal of nuclear medicine》2005,46(8):1256-1263
The goal of this study was to validate the accuracy of the Emory Cardiac Tool Box (ECTB) in assessing left ventricular end-diastolic or end-systolic volume (EDV, ESV) and ejection fraction (LVEF) from gated (99m)Tc-methoxyisobutylisonitrile ((99m)Tc-MIBI) SPECT using cardiac MRI (cMRI) as a reference. Furthermore, software-specific characteristics of ECTB were analyzed in comparison with 4D-MSPECT and Quantitative Gated SPECT (QGS) results (all relative to cMRI). METHODS: Seventy patients with suspected or known coronary artery disease were examined using gated (99m)Tc-MIBI SPECT (8 gates/cardiac cycle) 60 min after tracer injection at rest. EDV, ESV, and LVEF were calculated from gated (99m)Tc-MIBI SPECT using ECTB, 4D-MSPECT, and QGS. Directly before or after gated SPECT, cMRI (20 gates/cardiac cycle) was performed as a reference. EDV, ESV, and LVEF were calculated using Simpson's rule. RESULTS: Correlation between results of gated (99m)Tc-MIBI SPECT and cMRI was high for EDV (R = 0.90 [ECTB], R = 0.88 [4D-MSPECT], R = 0.92 [QGS]), ESV (R = 0.94 [ECTB], R = 0.96 [4D-MSPECT], R = 0.96 [QGS]), and LVEF (R = 0.85 [ECTB], R = 0.87 [4D-MSPECT], R = 0.89 [QGS]). EDV (ECTB) did not differ significantly from cMRI, whereas 4D-MSPECT and QGS underestimated EDV significantly compared with cMRI (mean +/- SD: 131 +/- 43 mL [ECTB], 127 +/- 42 mL [4D-MSPECT], 120 +/- 38 mL [QGS], 137 +/- 36 mL [cMRI]). For ESV, only ECTB yielded values that were significantly lower than cMRI. For LVEF, ECTB and 4D-MSPECT values did not differ significantly from cMRI, whereas QGS values were significantly lower than cMRI (mean +/- SD: 62.7% +/- 13.7% [ECTB], 59.0% +/- 12.7% [4DM-SPECT], 53.2% +/- 11.5% [QGS], 60.6% +/- 13.9% [cMRI]). CONCLUSION: EDV, ESV, and LVEF as determined by ECTB, 4D-MSPECT, and QGS from gated (99m)Tc-MIBI SPECT agree over a wide range of clinically relevant values with cMRI. Nevertheless, any algorithm-inherent over- or underestimation of volumes and LVEF should be accounted for and an interchangeable use of different software packages should be avoided. 相似文献
47.
Deficiency of an enzyme of tyrosine metabolism underlies altered gene expression in newborn liver of lethal albino mice. 总被引:12,自引:0,他引:12
Mice homozygous for albino deletions encompassing the locus alf/hsdr-1 die shortly after birth. Lethality is thought to be the consequence of hypoglycemia, which results from the failure to activate hormone-dependent genes in liver and kidney encoding enzymes important for gluconeogenesis. Within the region in which alf/hsdr-1 has been defined by physical mapping, we identified the gene encoding fumarylacetoacetate hydrolase (FAH), an enzyme of tyrosine metabolism. Lack of FAH activity should lead to accumulation of toxic tyrosine metabolites. In man, genetically determined FAH deficiency is the primary defect in tyrosinemia type I, a fatal liver disease of infants. Northern blot and in situ hybridization analysis of mouse tissues showed that the cell types that normally express FAH correspond to those that exhibit a phenotype in alf/hsdr-1 deletion mice. Moreover, we could mimic aspects of the alf/hsdr-1 deletion phenotype in vitro by treating primary hepatocyte cultures with an intermediate of tyrosine metabolism. These findings strongly suggest that alf/hsdr-1 encodes FAH and that absence of FAH is responsible for neonatal lethality in albino deletion mice. Mechanisms by which this metabolic defect might bring about alterations in gene expression characteristic of the alf/hsdr-1 deletion phenotype are discussed. 相似文献
48.
49.
50.
Thies H. Jochimsen 《Magnetic resonance in medicine》2005,53(4):991-991
The original article to which this Erratum refers was published in Magnetic Resonance in Medicine (2004) 52(4) 724–732. 相似文献