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Intertechnique agreement and interstudy reproducibility of strain and diastolic strain rate at 1.5 and 3 tesla: A comparison of feature‐tracking and tagging in patients with aortic stenosis 下载免费PDF全文
Anvesha Singh MBChB Christopher D. Steadman MBChB MD Jamal N. Khan MBChB BMedSci Mark A. Horsfield PhD Soliana Bekele BSc Sheraz A. Nazir MBChB Prathap Kanagala MBChB Nicholas G.D. Masca MSc Patrick Clarysse PhD Gerry P. McCann MBChB MD 《Journal of magnetic resonance imaging : JMRI》2015,41(4):1129-1137
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Intracellular calcium regulates basolateral potassium channels in a chloride-secreting epithelium. 总被引:5,自引:0,他引:5 下载免费PDF全文
M J Welsh J D McCann 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(24):8823-8826
The two individual cell membranes of epithelia are functionally coupled, so that changes in apical membrane conductance are paralleled by changes in basolateral K+ conductance. However, the signal that regulates basolateral K+ conductance, thereby coupling the two membranes, is unknown. We tested the hypothesis that the cellular calcium concentration, [Ca2+]c, may regulate basolateral K+ conductance in canine tracheal epithelium, a Cl- -secreting epithelium that shows marked membrane coupling. Three findings support the hypothesis. First, the intracellular Ca2+ antagonist 8-(diethylamino)octyl 3,4,5-trimethoxybenzoate hydrochloride (TMB-8) attenuated the secretory response. Second, the secretagogue epinephrine increased [Ca2+]c, as measured with quin-2. Third, we found a K+ channel that was activated by Ca2+ on the cytosolic side of the membrane. Thus, cytosolic Ca2+ regulates the basolateral K+ conductance and may be the signal responsible for functional coupling of the two cell membranes. 相似文献
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Giuseppina Emma Puglisi Anna Warzybok Sabine Hochmuth Chiara Visentin Arianna Astolfi Nicola Prodi 《International journal of audiology》2015,54(4):44-50
Objective: Development of an Italian matrix sentence test for the assessment of speech intelligibility in noise. Design: The development of the test included the selection, recording, optimization with level adjustment, and evaluation of speech material. The training effect was assessed adaptively during the evaluation measurements with six lists of 20 sentences, using open- and closed-set response formats. Reference data were established for normal-hearing listeners with adaptive measurements. Equivalence of the test lists was investigated using the open-set response format at three signal-to-noise ratios (SNRs). Study sample: A total of 55 normal-hearing Italian mother-tongue listeners. Results: The evaluation measurements at fixed SNRs resulted in a mean speech reception threshold (SRT) of ? 7.3 ± 0.2 dB SNR and slope of 13.3 ± 1.2 %/dB. The major training effect of 1.5 dB was observed for the first two consecutive measurements. Mean SRTs of ? 6.7 ± 0.7 dB SNR and ? 7.4 ± 0.7 dB SNR were found from the third to the sixth adaptive measurement for open- and closed-set test response formats, respectively. Conclusions: A good agreement has been found between the SRTs and slope and those of other matrix tests. Since sentences are difficult to memorize, the Italian matrix test is suitable for repeated measurements. 相似文献
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Andrew J. Davidson Karin Becke Jurgen de Graaff Gaia Giribaldi Walid Habre Tom Hansen Rodney W. Hunt Caleb Ing Andreas Loepke Mary Ellen McCann Gillian D. Ormond Alessio Pini Prato Ida Salvo Lena Sun Laszlo Vutskits Suellen Walker Nicola Disma 《Paediatric anaesthesia》2015,25(5):447-452
It is now well established that many general anesthetics have a variety of effects on the developing brain in animal models. In contrast, human cohort studies show mixed evidence for any association between neurobehavioural outcome and anesthesia exposure in early childhood. In spite of large volumes of research, it remains very unclear if the animal studies have any clinical relevance; or indeed how, or if, clinical practice needs to be altered. Answering these questions is of great importance given the huge numbers of young children exposed to general anesthetics. A recent meeting in Genoa brought together researchers and clinicians to map a path forward for future clinical studies. This paper describes these discussions and conclusions. It was agreed that there is a need for large, detailed, prospective, observational studies, and for carefully designed trials. It may be impossible to design or conduct a single study to completely exclude the possibility that anesthetics can, under certain circumstances, produce long‐term neurobehavioural changes in humans; however , observational studies will improve our understanding of which children are at greatest risk, and may also suggest potential underlying etiologies, and clinical trials will provide the strongest evidence to test the effectiveness of different strategies or anesthetic regimens with respect to better neurobehavioral outcome. 相似文献