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OBJECTIVES: To predict bimodal benefit before cochlear implantation, we compared the performances of participants with bimodal fitting and with a cochlear implant alone on speech perception tests. METHODS: Twenty-two children with a cochlear implant in one ear and a hearing aid in the other (bimodal fitting) were included. Several aided and unaided average hearing thresholds and the aided word recognition score of the hearing aid ear were related to the bimodal benefit on a phoneme recognition test in quiet and in noise. Results with bimodal fitting were compared to results with the cochlear implant alone on a phoneme recognition test in quiet and in noise. RESULTS: No relationship was found between any of the hearing thresholds or the aided phoneme recognition score of the hearing aid ear and the bimodal benefit on the phoneme recognition tests. At the group level, the bimodal scores on the phoneme recognition tests in quiet and in noise were significantly better than the scores with the cochlear implant alone. CONCLUSIONS: Preoperatively available audiometric parameters are not reliable predictors of bimodal benefit in candidates for cochlear implantation. Children with unilateral implants benefit from bimodal fitting on speech tests. This improvement in performance warrants the recommendation of bimodal fitting even when bimodal benefit cannot be predicted.  相似文献   
43.
Gentamicin-PMMA beads. Pharmacokinetic and nephrotoxicological study   总被引:2,自引:0,他引:2  
Five patients treated with gentamicin-polymethylmethacrylate (PMMA) beads were monitored during the treatment of nine to 14 days. Kinetic data of the gentamicin delivery were gathered constantly by multiple samples of blood and urine. The treatment with 48-360 beads caused a gentamicin serum concentration of 0.03-0.4 micrograms/ml and a renal excretion rate of 3-40 micrograms/min. The total amount of gentamicin excreted after the whole treatment was 20%-70%, with an in vivo half-life of 5.7-10 days. The gentamicin appeared to be released constantly during the entire treatment (nine to 14 days); the beads are kinetically slow release carriers. Despite precise measurement of tubular and glomerular renal function, no nephrotoxicity could be demonstrated. This local antibiotic gentamicin therapy may use the blood bone barrier effectively as a protection of the body against a very high local gentamicin concentration.  相似文献   
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Background  

Being unable to read is a major problem for visually impaired patients. Since distance visual acuity (VA) does not adequately reflect reading ability, it is important to also evaluate near VA. The Radner Reading Charts (RRCs) are available to measure patients’ reading performance. The present study tested the inter-chart and test-retest reliability of the RRCs in Dutch low-vision patients (i.e., visual acuity ≥0.3 logMAR) with various eye disorders.  相似文献   
45.
Temporal bones of 2 patients with Usher syndrome type I were examined using light microscopy. In both patients, findings from histopathologic examination of the cochlea were characterized by degeneration of the organ of Corti, which was most marked in the basal turn, atrophy of the stria vascularis, and a decrease in the number of spiral ganglion cells. The cochlear nerve appeared to be diminished. The sensory epithelium of the saccular and utricular maculae of patient 1 was normal for age. The left temporal bone of patient 2, classified as Usher syndrome genetic subtype USH1D or USH1F, demonstrated the typical signs of severe cochleosaccular degeneration. Present cases and cases from the literature were reviewed in search of an explanation for the above-described differences in histologic findings.  相似文献   
46.
Although deficiency of complex I of the mitochondrial respiratory chain is a frequent cause of encephalopathy in children, only a few mutations have been reported in each of its subunits. In the absence of families large enough for conclusive segregation analysis and of robust functional testing, it is difficult to unequivocally show the causality of the observed mutations and to delineate genotype-phenotype correlations, making additional observations necessary. We observed two consanguineous siblings with an early-onset encephalopathy, medulla, brainstem and mesencephalon lesions on brain magnetic resonance imaging and death before 8 months of age, caused by a complex I deficiency. We used a homozygosity mapping approach and identified a missense mutation in the NDUFV1 gene. The mutation, p.Arg386His, affects a highly conserved residue, contiguous to a cysteine residue known to coordinate an Fe ion. This observation adds to our understanding of complex I deficiency disease. It validates the important role of Arg386 and therefore supports the current molecular model of iron-sulfur clusters in NDUFV1.  相似文献   
47.

Background

Posttraumatic stress disorder (PTSD) develops in 10-20% of injury patients. We developed a novel, self-guided Internet-based intervention (called Trauma TIPS) based on techniques from cognitive behavioral therapy (CBT) to prevent the onset of PTSD symptoms.

Objective

To determine whether Trauma TIPS is effective in preventing the onset of PTSD symptoms in injury patients.

Methods

Adult, level 1 trauma center patients were randomly assigned to receive the fully automated Trauma TIPS Internet intervention (n=151) or to receive no early intervention (n=149). Trauma TIPS consisted of psychoeducation, in vivo exposure, and stress management techniques. Both groups were free to use care as usual (nonprotocolized talks with hospital staff). PTSD symptom severity was assessed at 1, 3, 6, and 12 months post injury with a clinical interview (Clinician-Administered PTSD Scale) by blinded trained interviewers and self-report instrument (Impact of Event Scale—Revised). Secondary outcomes were acute anxiety and arousal (assessed online), self-reported depressive and anxiety symptoms (Hospital Anxiety and Depression Scale), and mental health care utilization. Intervention usage was documented.

Results

The mean number of intervention logins was 1.7, SD 2.5, median 1, interquartile range (IQR) 1-2. Thirty-four patients in the intervention group did not log in (22.5%), 63 (41.7%) logged in once, and 54 (35.8%) logged in multiple times (mean 3.6, SD 3.5, median 3, IQR 2-4). On clinician-assessed and self-reported PTSD symptoms, both the intervention and control group showed a significant decrease over time (P<.001) without significant differences in trend. PTSD at 12 months was diagnosed in 4.7% of controls and 4.4% of intervention group patients. There were no group differences on anxiety or depressive symptoms over time. Post hoc analyses using latent growth mixture modeling showed a significant decrease in PTSD symptoms in a subgroup of patients with severe initial symptoms (n=20) (P<.001).

Conclusions

Our results do not support the efficacy of the Trauma TIPS Internet-based early intervention in the prevention of PTSD symptoms for an unselected population of injury patients. Moreover, uptake was relatively low since one-fifth of individuals did not log in to the intervention. Future research should therefore focus on innovative strategies to increase intervention usage, for example, adding gameplay, embedding it in a blended care context, and targeting high-risk individuals who are more likely to benefit from the intervention.

Trial Registration

International Standard Randomized Controlled Trial Number (ISRCTN): 57754429; http://www.controlled-trials.com/ISRCTN57754429 (Archived by WebCite at http://webcitation.org/6FeJtJJyD).  相似文献   
48.
The Neotropical Phyllostomidae family is the third largest in the order Chiroptera, with 56 genera and 140 species. Most researchers accept this family as monophyletic but its species are anatomically diverse and complex, leading to disagreement on its systematics and evolutionary relationships. Most of the genera of Phyllostomidae have highly conserved karyotypes but with intense intergeneric variability, which makes any comparative analysis using classical banding difficult. The use of chromosome painting is a modern way of genomic comparison on the cytological level, and will clarify the intense intergenus chromosomal variability in Phyllostomidae. Whole chromosome probes of species were produced as a tool for evolutionary studies in this family from two species from different subfamilies, Phyllostomus hastatus and Carollia brevicauda, which have large morphological and chromosomal differences, and these probes were used in reciprocal chromosome painting. The hybridization of the Phyllostomus probes on the Carollia genome revealed 24 conserved segments, while the Carollia probes on the Phyllostomus genome detected 26 segments. Many chromosome rearrangements have occurred during the divergence of these two genera. The sequence of events suggested a large number of rearrangements during the differentiation of the genera followed by high chromosomal stability within each genus.  相似文献   
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