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The present study addressed auditory processing in 8-11-year-old children with developmental dyslexia by means of event-related brain potentials (ERP). Cortical sound reception was evaluated by recording N250 responses to syllables and tones and cortical sound discrimination by analyzing the mismatch negativity (MMN) to syllable and tone changes. We found that both cortical sound reception and sound discrimination were impaired in dyslexic children. The analysis of the data obtained from two dyslexic subgroups, Dyslexics-1 being impaired in non-word reading (or both non-word and frequent word reading) and Dyslexics-2 in frequent word reading but not in non-word reading, revealed that the MMN was specifically diminished in the latter group whereas it was normal-like in Dyslexics-1. However, no differences were found between these subgroups in sound reception as indicated by the responses elicited by the standard stimuli. These results show that different diagnostic subgroups of dyslexics have different patterns of auditory processing deficits as suggested by similarly impaired sound reception in both dyslexic groups and the sound-discrimination impairment specific to one of the groups.  相似文献   
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Word-specific cortical activity as revealed by the mismatch negativity   总被引:3,自引:0,他引:3  
Neurophysiological brain activity evoked by individual spoken words and pseudowords was recorded and the mismatch negativity (MMN), an automatic index of experience-dependent auditory memory traces, was calculated. Consistent with earlier reported results, the MMN response to word-final syllables was enhanced compared with that elicited by the same syllables placed in a pseudoword context. Here we now demonstrate that the enhancement of the MMN elicited by two individual words showed different scalp topographies. The early word-specific brain activity is consistent with the assumption that the memory traces activated by individual words are carried by large neuronal ensembles that differ in their distributions over the cortex. Current source estimates localized the between-word differences in the right hemisphere and in parieto-occipital left-hemispheric areas. The differential brain responses to individual words appeared as early as ∼100 ms after the recognition points of the words, suggesting that their specific memory traces become active almost immediately after the information in the acoustic input is sufficient for word identification.  相似文献   
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BACKGROUND: Depression and burnout are common health problems in working populations today. They appear to be interrelated, and the need for their differential diagnosis has been highlighted in many reviews. We analysed the overlap of job-related burnout and depressive disorders, i.e., major depressive disorder, dysthymia, and minor depressive disorder. METHODS: We used the population-based 'Health 2000 Study' in Finland. Our nationally representative sample comprised 3276 employees aged 30-64 years. Burnout was assessed with the Maslach Burnout Inventory-General Survey. Diagnoses of depressive disorders were based on the Composite International Diagnostic Interview. RESULTS: Burnout and depressive disorders were clearly related. The risk of depressive disorders, especially major depressive disorder (12-month prevalence), was greater when burnout was severe. Half of the participants with severe burnout had some depressive disorder. Those with a current major depressive episode suffered from serious burnout more often than those who had suffered a major depressive episode earlier. LIMITATIONS: This study was cross-sectional. CONCLUSIONS: The concepts of burnout and depression complement each other and cover partly overlapping phenomena. Depressive disorders are related to job-related burnout, particularly when it is severe. A current major depressive episode is likely to be associated with the experience of burnout. When encountering working patients, it is recommended to assess both the occurrence of burnout and of depressive disorders.  相似文献   
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Cytokines are the most important inducers of T helper (Th) cell differentiation. Interleukin-12 (IL-12) and interferon-alpha (IFN-alpha) are responsible for human Th1-cell differentiation, while IL-4 is the critical cytokine promoting Th2-cell development. These two subsets of cells co-ordinate immunological responses to pathogens as well as autoimmune or allergic reactions. The pim family of proto-oncogenes encodes serine/threonine-specific kinases involved in cytokine-mediated signalling pathways in haematopoietic cells. Here we demonstrate that expression of pim-1 and pim-2 mRNAs is selectively up- or down-regulated in human cord-blood-derived CD4+ cells freshly induced to polarize towards Th1 or Th2 cells, respectively, whereas their expression is inhibited in both cell types by the immunosuppressive transforming growth factor beta (TGF-beta). Moreover, the Th1-specific cytokines IL-12 and IFN-alpha, but not the Th2-specific cytokine IL-4, transiently up-regulate pim-1 and pim-2 mRNA expression in human peripheral blood T cells and natural killer cells. In addition, the Pim-1 protein levels are strongly up-regulated by Th1-specific cytokines in all of these cell types. Taken together, our results suggest that pim genes and their protein products are involved in the early differentiation process of T helper cells.  相似文献   
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We investigated neural distinctions between inflectional and derivational morphology and their interaction with lexical frequency using the mismatch negativity (MMN), an established neurophysiological index of experience-dependent linguistic memory traces and automatic syntactic processing. We presented our electroencephalography (EEG) study participants with derived and inflected words of variable lexical frequencies against their monomorphemic base forms in a passive oddball paradigm, along with acoustically matched pseudowords. Sensor space and distributed source modelling results showed that at 100–150 msec after the suffix onset, derived words elicited larger responses than inflected words. Furthermore, real derived words showed advantage over pseudo-derivations and frequent derivations elicited larger activation than less frequent ones. This pattern of results is fully in line with previous research that explained lexical MMN enhancement by an activation of strongly connected word-specific long-term memory circuits, and thus suggests stronger lexicalisation for frequently used complex words. At the same time, a strikingly different pattern was found for inflectional forms: higher response amplitude for pseudo-inflections than for real inflected words, with no clear frequency effects. This is fully in line with previous MMN results on combinatorial processing of (morpho)syntactic stimuli: higher response to ungrammatical morpheme strings than grammatical ones, which does not depend on the string's surface frequency. This pattern suggests that, for inflectional forms, combinatorial processing route dominates over whole-form storage and access. In sum, our results suggest that derivations are more likely to form unitary representations than inflections which are likely to be processed combinatorially, and imply at least partially distinct brain mechanisms for the processing and representation of these two types of morphology. These dynamic mechanisms, underpinned by perisylvian networks, are activated rapidly, at 100–150 msec after the information arrives at the input, and in a largely automatic fashion, possibly providing neural basis for the first-pass morphological processing of spoken words.  相似文献   
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Scand J Caring Sci; 2010; 24; 65–74
Are the children of the clients' visible or invisible for nurses in adult psychiatry? – a questionnaire survey Children in families affected by mental illness are at an increased risk for developing psychopathology, emotional and behavioural problems. Nurses have direct and frequent contact with patients and their families, and are in a unique position to evaluate the situation of these children before problems arise. The aim of this study is to describe the interaction that practical mental health nurses (MHNs) and registered mental health currently have with children of their clients and predictors of this interaction when a parent is receiving psychiatric care. This is a cross‐sectional study. In 2005, questionnaires were sent to all registered (n = 373) and practical MHNs (n = 235) working in 45 adult psychiatric inpatient and outpatient units in five Finnish university hospitals. The total response rate was 51%, while 60% (n = 222) of registered MHNs and 36% (n = 88) of practical MHNs responded. Most of the nurses did not meet children of their clients regularly, although they reported that information about children of the clients were gathered regularly at the units, and discussed clients′ children with them. The personal characteristics of nurses, such as gender, age, marital status and being a parent, were significantly related to the nurse’s propensity to pay attention to the children of their clients in adult psychiatry. Nurses’ professional experience, further family education and use of family‐centred care at the unit increased their interaction with the children of their patients. These results indicate that clients’ children are not entirely invisible for most of the nurses in adult psychiatry. Knowledge of the risks faced by these children and implementation of the preventive approach should be included in the basic education of nurses.  相似文献   
10.
Macrophage-inhibitory cytokine-1 (MIC-1) is a divergent member of the transforming growth factor beta superfamily. It is up-regulated by nonsteroidal anti-inflammatory drugs and is highly expressed in human prostate cancer leading to high serum MIC-1 concentrations with advanced disease. A role for MIC-1 has been implicated in the process of early bone formation, suggesting that it may also mediate sclerosis at the site of prostate cancer bone metastases. Consequently, the aim of this study was to retrospectively determine the relationship of serum MIC-1 concentration and other markers related to current and future prostate cancer bone metastasis in a cohort of 159 patients with prostate cancer. Serum markers included cross-linked carboxy-terminal telopeptide of type I collagen, prostate-specific antigen, and amino-terminal propeptide of type I procollagen (PINP). The mean values of all the biomarkers studied were significantly higher in patients with baseline bone metastases (BM+, n = 35), when compared with those without bone metastases (BM-, n = 124). In a multivariate logistic model, both MIC-1 and PINP independently predicted the presence of baseline bone metastasis. Based on receiver operator curve analysis, the best predictor for the presence of baseline bone metastasis was MIC-1, which was significantly better than carboxy-terminal telopeptide of type I collagen, prostate-specific antigen, and PINP. Patients who experienced bone relapse had significantly higher levels of baseline MIC-1 compared with patients who did not (1476.7 versus 988.4; P = 0.03). Current use of acetylsalicylic acid did not influence serum MIC-1 levels in this cohort. Although requiring validation prospectively, these results suggest that serum MIC-1 determination may be a valuable tool for the diagnosis of current and future bone metastases in patients with prostate cancer.  相似文献   
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