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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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Numeric (Nv) and volume (Vv) densities, as well as the average size (skeleton: Sk) of synaptic mitochondria from adult, normally fed and adult, vitamin E deficient animals (11 months of age) were semiautomatically measured by computer-assisted morphometry in the cerebellar granular layer. Nv, Vv and the average mitochondrial volume (V) were measured on perikaryal Purkinje cell organelles preferentially stained for succinic dehydrogenase (SDH) activity. Adult vitamin E deficient animals showed a significant decrease of Nv, a significant increase of Sk and an unchanged value of Vv. While in adult normally fed animals the mitochondria of increased size (Sk>5 microm) were 5.3%, in the adult vitamin E deficient rats this fraction accounted for 25.5%. In Purkinje cell perikarya, vitamin E deficiency resulted in a significant decrease of Vv, Nv and V, as well as a steeper reduction of the percentage of SDH-positive mitochondria of larger size. Taken together, these findings document that vitamin E deficiency is responsible of mitochondrial morphometric alterations in adult rats. Structurally deteriorated mitochondria are reported to play a role in producing increased amounts of free radicals, which can facilitate the accumulation of ceroid pigment.  相似文献   
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We assessed whether macrophage colony-stimulating factor (M-CSF) levels are associated with left ventricular systolic dysfunction (LVSD) in patients with acute myocardial infarction (AMI). We studied 56 patients with AMI (mean age: 67 ± 12 years) and identified those with clinical (Killip class >II) or echocardiographic signs (ejection fraction ≤45%) of LVSD. We evaluated the established cardiovascular risk factors and measured several cardiovascular biomarkers, including M-CSF. Serum M-CSF concentrations (pg/mL) were significantly increased in patients with both clinical and echocardiographic signs of LVSD (460 ± 265 vs 290 ± 210, P = .0103 and 493 ± 299 vs 287 ± 174, P = .0028, respectively). We found a significant inverse association between M-CSF and ejection fraction (r = -.351, P = .0079). Logistic regression analysis revealed that, among all evaluated clinical and biochemical parameters, the stronger predictor of LVSD was M-CSF (odds ratios 2.1, 95% confidence interval 1.1-2.9, P = .0168). This is the first study reporting plasma M-CSF levels as independent determinants of low LV ejection fraction and clinical LV dysfunction in patients with AMI.  相似文献   
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A multicenter randomized open-label long-term sequential deferiprone–deferoxamine (DFP-DFO) versus DFP alone trial (sequential DFP-DFO) performed in patients with thalassemia major (TM) was retrospectively reanalyzed to assess the variation in the left ventricular ejection fraction (LVEF) [1].  相似文献   
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Most of the commonly used antidepressants block monoamine reuptake transporters to enhance serotonergic or noradrenergic neurotransmission. Effects besides or downstream of monoamine reuptake inhibition are poorly understood and yet presumably important for the drugs' mode of action. In the present study we aimed at identifying hippocampal cellular pathway alterations in DBA/2 mice using paroxetine as a representative Selective Serotonin Reuptake Inhibitor (SSRI). Furthermore we identified biomarker candidates for the assessment of antidepressant treatment effects in plasma. Hippocampal protein levels were compared between chronic paroxetine- and vehicle-treated animals using in vivo15N metabolic labeling combined with mass spectrometry. We also studied the time course of metabolite level changes in hippocampus and plasma using a targeted polar metabolomics profiling platform. In silico pathway analyses revealed profound alterations related to hippocampal energy metabolism. Glycolytic metabolite levels acutely increased while Krebs cycle metabolite levels decreased upon chronic treatment. Changes in energy metabolism were influenced by altered glycogen metabolism rather than by altered glycolytic or Krebs cycle enzyme levels. Increased energy levels were reflected by an increased ATP/ADP ratio and by increased ratios of high-to-low energy purines and pyrimidines. In the course of our analyses we also identified myo-inositol as a biomarker candidate for the assessment of antidepressant treatment effects in the periphery. This study defines the cellular response to paroxetine treatment at the proteome and metabolome levels in the hippocampus of DBA/2 mice and suggests novel SSRI modes of action that warrant consideration in antidepressant development efforts.  相似文献   
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