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It is claimed that neurofeedback (NF) is an effective treatment for a variety of psychiatric disorders. NF, within an operant conditioning framework, helps individuals to regulate cortical electroencephalographic (EEG) activity while receiving feedback from a visual or acoustic signal. For example, changing asymmetry between left and right frontal brain alpha activity by NF, is claimed to be an efficacious treatment for major depressive disorder. However, the specificity of this intervention in occasioning electrophysiological changes at target locations and target wave-frequencies, and its relation to changes in mood, has not been established. During a single session of NF, it was tested if the balance between left and right frontal alpha-activity could be changed, regardless of direction, in 40 healthy females. Furthermore, we investigated whether this intervention was electrophysiologically specific and if it was associated with changes in mood. Participants were able to decrease or increase frontal alpha-asymmetry during the intervention. However, no changes in mood were observed. Changes in EEG activity were specific in terms of location and wave-frequency.  相似文献   
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BackgroundPeriodontal disease is a major cause of tooth loss. Few studies have evaluated the residual area of the periodontal ligament in extracted teeth and, to the best of our knowledge, none from Latin America have done so regarding indications for extraction. The aim of this study was to evaluate the residual periodontal ligament (RPL) with respect to indication for extraction in a sample of teeth from a Brazilian Public Health Service district.Materials and methodsAll teeth extracted within the Public Health Service district of Santa Maria, Brazil, over a 5-month period were requested for analysis. A total of 414 teeth eligible for measurement were stained and evaluated for RPL using a stereo microscope. Participating Public Health Service dentists completed a questionnaire detailing demographic variables and indication for each extracted tooth. The percentage of RPL was determined for each tooth. Comparisons of RPL between teeth extracted on periodontal versus other indications were made using the Mann-Whitney test.ResultsRPL averaged 34.8% for teeth extracted on periodontal indications versus 79.5% for other teeth (P ≤ 0.001). When considering teeth with an RPL ≥ 30% as possible to maintain, 189 (76%) of the teeth extracted on periodontal indications could have been maintained. When RPL cut-off limits of ≥ 40% or ≥ 50% are applied, 93 (37%) and 43 (17%) teeth, respectively, could have been maintained.ConclusionThis study suggests that strictly based on RPL, a large number of teeth extracted on periodontal indications conceivably could be maintained.Key words: Cross-sectional studies, Prognosis, Tooth extraction, Tooth loss  相似文献   
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ObjectiveThis study assessed levels of anxiety, depression, and stress among family caregivers of children and adolescents with mental disorders in Ghana and the implication on medication adherence.DesignA cross-sectional study.SettingThe study was conducted at the outpatient departments of the three main public psychiatric hospitals in Ghana.ParticipantsTwo hundred and ten non-paid family caregivers of children and adolescents with mental disorders were recruited for this study.Main Outcome MeasureThe study assessed symptoms of anxiety, depression and stress among the caregivers and estimated caregiver-reported medication adherence.ResultsAbout 56.2%, 66.2% and 78% of the caregivers experienced severe anxiety, severe depression and moderate to severe stress symptoms respectively. From the multiple logistic regression model, while anxiety was significantly affected by religion and education, depression was influenced by sex, age, marital status, proximity to facility, and employment status. Female caregivers had about four times higher odds of being depressed compared to male caregivers (aOR: 3.81, 95% CI: 1.66 – 8.75). The caregiver-reported medication adherence was 11.9%. Anxiety was significantly predictive of medication adherence.ConclusionMost family caregivers of children and adolescents with mental disorders experienced symptoms of anxiety, depression and stress with anxiety having implications for medication adherence. The study findings underscore the need to consider psychological characteristics of caregivers and the provision of mental health support for them, as part of the routine health care for children and adolescents with mental disorders.FundingNone indicated  相似文献   
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PURPOSE: Sonographic calculation of thyroid volume is used in the diagnosis and follow-up of thyroid diseases. Since the calculated volume of thyroid lobes is highly influenced by the longest (ie, craniocaudal) diameter, we examined whether using a curved-array transducer as opposed to a linear-array transducer to measure the craniocaudal diameter would reduce interobserver variation. METHODS: Three sonographers with different levels of expertise each used a 5-12-MHz linear-array transducer and a 2-5-MHz curved-array transducer to measure the craniocaudal diameter of both thyroid lobes of 25 healthy volunteers. On the basis of these measurements, thyroid lobe volumes were calculated. Single-factor analysis of variance was used to evaluate the interobserver variations between the measurements made by all 3 observers as well as between measurements taken by pairs of observers. A p value of less than 0.05 was considered significant. RESULTS: Using the linear-array transducer to measure the craniocaudal diameter resulted in significant interobserver variation in thyroid volume calculation (p = 0.02), whereas using the convex-array transducer did not. Using either transducer resulted in a highly significant interobserver variation in measurements of the craniocaudal diameter, although the variation was far more pronounced for measurements made with the linear-array transducer (p = 0.0005) than for those made with the curved-array transducer (p = 0.04). For both transducers, the interobserver variations were most pronounced between the most and the least experienced sonographers. CONCLUSIONS: To avoid significant interobserver variation in calculating thyroid lobe volume, we recommend using a curved-array transducer to measure the craniocaudal diameter of the thyroid lobes.  相似文献   
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The ecology of ebolaviruses is still poorly understood and the role of bats in outbreaks needs to be further clarified. Straw-colored fruit bats (Eidolon helvum) are the most common fruit bats in Africa and antibodies to ebolaviruses have been documented in this species. Between December 2018 and November 2019, samples were collected at approximately monthly intervals in roosting and feeding sites from 820 bats from an Eidolon helvum colony. Dried blood spots (DBS) were tested for antibodies to Zaire, Sudan, and Bundibugyo ebolaviruses. The proportion of samples reactive with GP antigens increased significantly with age from 0–9/220 (0–4.1%) in juveniles to 26–158/225 (11.6–70.2%) in immature adults and 10–225/372 (2.7–60.5%) in adult bats. Antibody responses were lower in lactating females. Viral RNA was not detected in 456 swab samples collected from 152 juvenile and 214 immature adult bats. Overall, our study shows that antibody levels increase in young bats suggesting that seroconversion to Ebola or related viruses occurs in older juvenile and immature adult bats. Multiple year monitoring would be needed to confirm this trend. Knowledge of the periods of the year with the highest risk of Ebolavirus circulation can guide the implementation of strategies to mitigate spill-over events.  相似文献   
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