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Auditory responses to speech sounds that are self-initiated are suppressed compared to responses to the same speech sounds during passive listening. This phenomenon is referred to as speech-induced suppression, a potentially important feedback-mediated speech-motor control process. In an earlier study, we found that both adults who do and do not stutter demonstrated a reduced amplitude of the auditory M50 and M100 responses to speech during active production relative to passive listening. It is unknown if auditory responses to self-initiated speech-motor acts are suppressed in children or if the phenomenon differs between children who do and do not stutter. As stuttering is a developmental speech disorder, examining speech-induced suppression in children may identify possible neural differences underlying stuttering close to its time of onset. We used magnetoencephalography to determine the presence of speech-induced suppression in children and to characterize the properties of speech-induced suppression in children who stutter. We examined the auditory M50 as this was the earliest robust response reproducible across our child participants and the most likely to reflect a motor-to-auditory relation. Both children who do and do not stutter demonstrated speech-induced suppression of the auditory M50. However, children who stutter had a delayed auditory M50 peak latency to vowel sounds compared to children who do not stutter indicating a possible deficiency in their ability to efficiently integrate auditory speech information for the purpose of establishing neural representations of speech sounds.  相似文献   
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Middle-latency somatosensory evoked potentials (SEPs) of particularly large amplitude (giant) have been reported in subjects with benign childhood epilepsy with centrotemporal spikes (BECT) and in normal children, which usually show significant age-related changes. However, the mechanisms by which age modifies the appearance of centrotemporal spikes and giant SEPs in these children, are not known. The characteristics of SEPs were studied in a group of 18 subjects (10 males and 8 females, aged 7.1-17.2 years) with sleep-enhanced centrotemporal spikes, with or without BECT and the results were compared with those obtained from a group of age-matched normal controls. Giant SEPs were recorded in 6 subjects and, in 3 of these, EEG spikes evoked by hand tapping were obtained also. No subjects with giant SEPs were found in subjects older than 12 years, and an age-related decrease in amplitude of giant SEPs as this age approached was observed. Moreover, at repeated SEP recordings, a clear trend towards a more important reduction in amplitude of giant SEPs over the temporal and parietal than over the central regions was evident. The study of EEG spikes evoked by hand tapping showed a striking similarity between the averaged evoked spikes and the main negative component of giant SEPs. It was also possible to observe that the spike negative peak recorded over the central areas always preceded the same component recorded over the parietal and temporal areas by 5-15 ms. Our study seems to support the idea that giant SEPs in subjects with centrotemporal spikes are generated by a complex mechanism different from that at the basis of the normal N60 component of SEPs; they also show peculiar age-related modifications which can be interpreted in terms of maturational changes of brain excitability/inhibition and probably constitute a tool for monitoring the clinical course of BECT, when present.  相似文献   
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Background: Esophageal cancer is among the most deadly cancers worldwide, and esophagectomy remains the standard of care in trying to cure this. Efforts to decrease the incidence of complications in esophagectomy without compromising the efficacy of the procedure have stimulated interest in minimally invasive esophagectomy (MIE), and a wide variety of MIE techniques have been refined by surgeons at specialized centers worldwide. Data sources: Systematic PubMed searches identified articles related to MIE technique, complications, and outcomes. Conclusions: Several techniques have been developed for MIE, none of which has been deemed superior, but as a whole, they represent a safe alternative to open surgery. Available results from case series and comparative studies suggest trends towards improved short‐term outcomes with equivalent efficacy but without definitive advantages.  相似文献   
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BACKGROUND: No extensive studies are available in the literature on the eventual skin pathology induced by neurologic or systemic diseases in elderly individuals. Other factors, such as health and hygiene, socioeconomic status, and climate can also play an important role. METHODS: Fifteen-hundred subjects (886 women and 614 men; mean age, 67.8 years; range, 39-90 years) were admitted to the Department of Geriatrics at the Oasi Institute between 1992 and 1997; all these subjects were carefully evaluated from a dermatologic point of view. Each subject underwent specialist examinations, routine blood analyses, thoracic X-rays, cerebral computerized tomography (CT) scan, and magnetic resonance imaging (MRI) when appropriate. A group of subjects without significant neurologic or systemic disease, comprising 116 women and 60 men (mean age, 64.5 years; range, range, 40-90 years), was selected and used as a normal control group. Subsequently, our attention was focused on the eventual presence of the following neurologic diseases: Alzheimer-type dementia, vascular dementia, mixed-type dementia, subcortical dementia, Parkinson's disease, vascular brain disease, hemiplegia, etc. Thus, different subgroups were formed on the basis of such diagnostic categories and the frequency of skin pathology in each subgroup was evaluated. RESULTS: Of the 1500 subjects, 1439 stated that they had never been affected by dermatologic disease. No statistically significant difference in frequency of skin pathology was found between normal controls and the different patient subgroups. Unsuspected and singular dermatoses were found, however, such as paraneoplastic syndromes, idiopathic tripe palms, white fibrous papulosis of the neck as an expression of photoaging, conditions induced by former popular traditions of Sicilian culture (anetoderma secondary to the application of Hirudo medicinalis and erythema ab igne), pigmented dermatoses never described before in Italy (prurigo pigmentosa and friction amyloidosis), and nail abnormalities (atypical half-and-half nail, and dyschromic nail changes in multiple system atrophy and in hemiplegia). CONCLUSIONS: The dermatologic screening performed in 1500 patients revealed several unexpected diagnoses and some original observations. Some rare dermatoses were described and certain hypotheses were suggested to explain the peculiar dyschromic changes of the fingernails in multiple system atrophy, the atypical cases of half-and-half nail, and the so-called idiopathic tripe palms associated with psoriasis.  相似文献   
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Purpose:Cancer stem cells (CSCs) reported in various tumors play a crucial role in tumorigenesis and metastasis of retinoblastoma (Rb). Following the efforts to reduce, replace, and refine the use of mammalian models, we aimed to establish a short-term xenograft for Rb to evaluate the CSC properties of CD133- Rb Y79 cells, using the well-established chick embryo chorioallantoic membrane (CE-CAM) assay.Methods:Y79 cells were cultured, labeled with two different dyes (CM-Dil Y79 and enhanced green fluorescent protein (eGFP)) and sorted for CD133- and CD133 + subsets. Two million cells from each of the labeled groups were transplanted onto the abraded CAM on embryonic day 7 (E7). On E14, the tumor nodule formation on CAM and spontaneous metastasis to the embryos were evaluated by confocal microscopy, in vivo imaging, and histology.Results:Y79 cells formed pink–white raised perivascular nodules with feeder vessels on the CAM with both the types of labeled CD133- cells. CD133- cells, when compared to CD133 + cells, demonstrated significantly larger tumor volume (40.45 ± 7.744 mm3 vs 3.478 ± 0.69 mm3, P = 0.0014) and higher fluorescence intensity (CM-Dil: AUF = 6.37 × 107 ± 7.7 × 106 vs 1.08 × 107 ± 1.6 × 106; P < 0.0001; eGFP: AUF = 13.94 × 104 ± 2.54 × 104 vs AUF = 1.39 × 104 ± 0.4 × 104; P = 0.0003). The metastatic potential of CD133- cells was also observed to be higher as noted by in vivo imaging and histopathology.Conclusion:This study highlights that CE-CAM is a feasible alternative nonmammalian model for evaluating tumorigenicity and metastatic potential of Y79 CSCs. Increased tumorigenicity and metastatic potential of CD133- subset of tumor cells substantiate their CSC properties.  相似文献   
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