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OBJECTIVE: This study aimed to describe the use of the P300 event-related potential as a control signal in a brain computer interface (BCI) for healthy and paralysed participants. METHODS: The experimental device used the P300 wave to control the movement of an object on a graphical interface. Visual stimuli, consisting of four arrows (up, right, down, left) were randomly presented in peripheral positions on the screen. Participants were instructed to recognize only the arrow indicating a specific direction for an object to move. P300 epochs, synchronized with the stimulus, were analyzed on-line via Independent Component Analysis (ICA) with subsequent feature extraction and classification by using a neural network. RESULTS: We tested the reliability and the performance of the system in real-time. The system needed a short training period to allow task completion and reached good performance. Nonetheless, severely impaired patients had lower performance than healthy participants. CONCLUSIONS: The proposed system is effective for use with healthy participants, whereas further research is needed before it can be used with locked-in syndrome patients. SIGNIFICANCE: The P300-based BCI described can reliably control, in 'real time', the motion of a cursor on a graphical interface, and no time-consuming training is needed in order to test possible applications for motor-impaired patients.  相似文献   
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Paediatric dacryocystorhinostomy   总被引:1,自引:0,他引:1  
Of 258 cases of dacryocystorhinostomy performed on children in the period September 1981 to September 1991, 130 were for simple, unresolved congenital nasolacrimal duct obstruction. Other indications for surgery included punctal agenesis, lacrimal fistula, post-traumatic and post-inflammatory canalicular obstruction. Of 177 children without canalicular pathology, 171 (96%) were relieved of symptoms with one operation, without canalicular intubation. Of 81 cases with canalicular disease, 55 of 70 (79%) who underwent DCR plus canalicular intubation, and 10 of 11 who underwent DCR plus Lester-Jones tube, were substantially improved with one operation. No child required peroperative or postoperative blood transfusion. Dacryocystorhinostomy in childhood, in experienced surgical hands, is a safe procedure, achieving relief of symptoms in most cases, particularly in the absence of canalicular disease.  相似文献   
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In a population-based longitudinal cohort study, we tested the hypothesis that children growing up in a high-traffic polluted urban area (UA) in the Athens' basin have higher prevalence of allergies and sensitization when compared with those growing up in a Greek provincial rural area (RA). We recruited 478 and 342 children aged 8-10 living in the UA and the RA, respectively. Respiratory health was assessed by a parent-completed questionnaire in three phases: 1995-96 (phase 1), 1999-2000 (phase 2), 2003-04 (phase 3) and skin-prick testing to common indoor and outdoor aeroallergens was performed at phases 1 and 2. Reported asthma and eczema did not differ between the two areas, whereas reported hay fever was persistently more prevalent in the UA than in the RA (16.5%, 17.0%, 18.2% vs. 7.0%, 8.3%, 9.6%, respectively). Sensitization was more prevalent in the UA at both phases (19.0% vs. 12.1% in phase 1, 20.0% vs. 14.1% in phase 2). Residential area contributed independently to sensitization to >or=1 aeroallergens (OR: 0.29; 95% CI: 0.13-0.66; p = 0.003) and to polysensitization (OR: 0.28; 95% CI: 0.10-0.82; p = 0.020) in phase 1. These associations were independent of farming practices. No significant contributions were found in phase 2. Our results suggest that long-term exposure to urban environment is associated with a higher prevalence of hay fever but not of asthma or eczema. The negative association between rural living and the risk of atopy during childhood, which is independent of farming practices, implies that it is mainly driven by an urban living effect.  相似文献   
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The present authors evaluated adrenal reserve in asthmatic children on long-term inhaled corticosteroids and whether possible adrenal suppression could be predicted by growth retardation. Low-dose synacthen test (0.5 microg x 1.73 m(-2)) was performed in 72 asthmatic children with a median age of 9.4 (range 4.2-15.7) yrs on long-term treatment (median 18 (range 6-84) months) with low-to-moderate doses (median 363 (range 127-1012) microg x m(-2)) of inhaled budesonide, as well as in 30 controls. Adrenal suppression was considered as a peak serum cortisol <495 nmol x L(-1). The current authors calculated height standard deviation score (HSDS) at the time of testing and height velocity SDS (HVSDS) in the preceding year. Mean HSDS was 0.06+/-1.3 and HVSDS was -0.9+/-2.3. Adrenal suppression was disclosed in 15 asthmatic children (20.8%). There were no differences in HSDS and HVSDS between children with and without adrenal suppression. There was no correlation between peak cortisol response and dose or duration of treatment. However, a positive relationship between HVSDS and duration of treatment was noted. These data suggest that long-term treatment of asthmatic children with low and moderate doses of inhaled budesonide may result in mild adrenal suppression that cannot be predicted by growth deceleration. The negative influence of inhaled corticosteroids on growth becomes less the longer the duration of treatment.  相似文献   
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恶性肿瘤患者血清与尿液中一氧化氮含量测定   总被引:1,自引:1,他引:0  
0 引言一氧化氮(Nitric oxide,NO)是一种具有活跃生物化学性质的无机小分子. NO对许多肿瘤细胞和微生物有细胞毒性[1],为探讨NO与肿瘤的关系,我们检测了119例恶性肿瘤患者血清及尿液中的NO.  相似文献   
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Background and aimEating behaviours and obesity status among children have already been evaluated in several studies, with conflicting results. The aim of this study is to assess the correlation of breakfast cereal with childhood obesity.Methods and resultsA representative sample of 700 children (323 male) selected from 18 schools located in Athens greater area were enrolled. Children and their parents completed questionnaires that evaluated dietary habits and physical activity. We also retrieved information about the type of breakfast most frequently consumed. Height and weight of the children was measured and body mass index (BMI) was calculated. Simple and multiple logistic regression methods were used in order to determine the relationship between cereal intake for breakfast and obesity.Some boys (8.6%) and girls (9.0%) were obese, whereas 33.9% of boys and 22.1% of girls were overweight. For boys, the adjusted odds ratio for breakfast cereal intake for being overweight or obese was 0.54 (95% confidence interval (CI): 0.45–1.29), while for girls it was 0.41 (95% CI: 0.21–0.79). Moreover, the odds ratio of overweight/obesity for boys who ate daily breakfast was 0.51 (95% CI: 0.25–1.05), and for girls was 0.27 (95% CI: 0.12–0.64), adjusted for physical activity and other potential confounders.ConclusionThese data provide evidence that breakfast cereal as a most frequent choice, and daily consumption of breakfast, are inversely associated with the prevalence of overweight or obesity in 10–12-year-old children.  相似文献   
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Dommisch  H.  Stolte  KN.  Jager  J.  Vogel  K.  Müller  R.  Hedtrich  S.  Unbehauen  M.  Haag  R.  Danker  K. 《Clinical oral investigations》2021,25(10):5795-5805
Objectives

Topical drug administration is commonly applied to control oral inflammation. However, it requires sufficient drug adherence and a high degree of bioavailability. Here, we tested the hypothesis whether an ester-based core-multishell (CMS) nanocarrier is a suitable nontoxic drug-delivery system that penetrates efficiently to oral mucosal tissues, and thereby, increase the bioavailability of topically applied drugs.

Material and methods

To evaluate adhesion and penetration, the fluorescence-labeled CMS 10-E-15-350 nanocarrier was applied to ex vivo porcine masticatory and lining mucosa in a Franz cell diffusion assay and to an in vitro 3D model. In gingival epithelial cells, potential cytotoxicity and proliferative effects of the nanocarrier were determined by MTT and sulphorhodamine B assays, respectively. Transepithelial electrical resistance (TEER) was measured in presence and absence of CMS 10-E-15-350 using an Endohm-12 chamber and a volt-ohm-meter. Cellular nanocarrier uptake was analyzed by laser scanning microscopy. Inflammatory responses were determined by monitoring pro-inflammatory cytokines using real-time PCR and ELISA.

Results

CMS nanocarrier adhered to mucosal tissues within 5 min in an in vitro model and in ex vivo porcine tissues. The CMS nanocarrier exhibited no cytotoxic effects and induced no inflammatory responses. Furthermore, the physical barrier expressed by the TEER remained unaffected by the nanocarrier.

Conclusions

CMS 10-E-15-350 adhered to the oral mucosa and adhesion increased over time which is a prerequisite for an efficient drug release. Since TEER is unaffected, CMS nanocarrier may enter the oral mucosa transcellularly.

Clinical relevance

Nanocarrier technology is a novel and innovative approach for efficient topical drug delivery at the oral mucosa.

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