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31.
Tsiaras V Simos PG Rezaie R Sheth BR Garyfallidis E Castillo EM Papanicolaou AC 《Computers in biology and medicine》2011,(12):1166-1177
The present study is a preliminary attempt to use graph theory for deriving distinct features of resting-state functional networks in young adults with autism spectrum disorder (ASD). Networks modeled neuromagnetic signal interactions between sensors using three alternative interdependence measures: (a) a non-linear measure of generalized synchronization (robust interdependence measure [RIM]), (b) mutual information (MI), and (c) partial directed coherence (PDC). To summarize the information contained in each network model we employed well-established global graph measures (average strength, assortativity, clustering, and efficiency) as well as graph measures (average strength of edges) tailored to specific hypotheses concerning the spatial distribution of abnormalities in connectivity among individuals with ASD. Graph measures then served as features in leave-one-out classification analyses contrasting control and ASD participants. We found that combinations of regionally constrained graph measures, derived from RIM, performed best, discriminating between the two groups with 93.75% accuracy. Network visualization revealed that ASD participants displayed significantly reduced interdependence strength, both within bilateral frontal and temporal sensors, as well as between temporal sensors and the remaining recording sites, in agreement with previous studies of functional connectivity in this disorder. 相似文献
32.
33.
Konstantinos IOANNIDIS Ilias MISTAKIDIS Panagiotis BELTES Vassilis KARAGIANNIS 《Journal of applied oral science : revista FOB》2013,21(2):138-144
Crown discoloration can be induced by root canal sealer remnants following root canal
treatment.
Objective:
The aim of this study was to evaluate chromatic alterations in human tooth crowns induced by a Mineral Trioxide Aggregate-based sealer (MTA Fillapex® and a commonly used ZnOE-based sealer (Roth-811). The tested null hypothesis was that the application of the materials did not induce clinically perceptible crown discoloration (Ho: CIE color difference ΔE<3.7).Material and Methods:
Forty five fully developed, intact, mandibular third molars were sectioned 1 mm below the cemento-enamel junction. The pulp chambers were chemomechanically debrided via the cervical access. The specimens were randomly assigned into three groups Group 1: MTA Fillapex, Group 2: Roth 811, Group 3: Negative control (unfilled) and immersed in individually marked vials containing distilled water up to the cervix (37±1º C). The spectral reflectance lines were recorded by utilizing a UV-VIS spectrophotometer equipped with integration sphere in the visual spectrum at baseline, 1 week, 1 and 3 months after material placement. Data were transformed into values of the CIE L*a*b* color system and the corresponding ΔE values were calculated. Statistical analysis was performed using two-way mixed ANOVA models, at p=0.05 level of significance.Results:
A statistically significant increase in a* and b* chromatic parameters of the MTA Fillapex Group was measured. However, ΔE values did not exceed the human eye perceptibility threshold (set at ΔE<3.7) during the experimental period (ΔEt3=2.88). In Roth-811 Group, a statistically significant decrease in L* and a statistically significant increase in a* and b* chromatic parameters was measured, during all observation periods. Resultant ΔE values exceeded the human eye perceptibility threshold after 1 week (ΔEt1=5.65).Conclusions:
Application of MTA Fillapex in tooth crowns resulted in minimal color alterations, while Roth 811 induced severe discoloration, in vitro. It could be suggested that, in terms of aesthetics, the use of MTA Fillapex appears to be favorable. 相似文献34.
Werend Boesmans Marlene M. Hao Candice Fung Zhiling Li Chris Van den Haute Jan Tack Vassilis Pachnis Pieter Vanden Berghe 《Glia》2019,67(6):1167-1178
Coordination of gastrointestinal function relies on joint efforts of enteric neurons and glia, whose crosstalk is vital for the integration of their activity. To investigate the signaling mechanisms and to delineate the spatial aspects of enteric neuron-to-glia communication within enteric ganglia we developed a method to stimulate single enteric neurons while monitoring the activity of neighboring enteric glial cells. We combined cytosolic calcium uncaging of individual enteric neurons with calcium imaging of enteric glial cells expressing a genetically encoded calcium indicator and demonstrate that enteric neurons signal to enteric glial cells through pannexins using paracrine purinergic pathways. Sparse labeling of enteric neurons and high-resolution analysis of the structural relation between neuronal cell bodies, varicose release sites and enteric glia uncovered that this form of neuron-to-glia communication is contained between the cell body of an enteric neuron and its surrounding enteric glial cells. Our results reveal the spatial and functional foundation of neuro-glia units as an operational cellular assembly in the enteric nervous system. 相似文献
35.
Nikolaos Papadogeorgakis Vassilis Petsinis Efstathios Eleftheriades Stefanos Dimtsas Dimitra Protopappa Constantinos Alexandridis 《Oral and maxillofacial surgery》2009,13(3):171-175
Introduction
Olfactory neuroblastomas are rare malignant tumors that usually occur in the upper nasal cavity. The purpose of this paper is to present a case of a large olfactory neuroblastoma filling the entire nasal cavity, treated with an Altemir technique modification.Methods
A 39-year-old woman presented with a large tumor of the nasal cavity. After the laboratory examinations, the tumor was classified as a Kadish stage A olfactory neuroblastoma. The selected treatment was the surgical excision after an Altemir technique modification combined with midfacial degloving and additional radiotherapy.Results
Histopathology revealed a Hyams grade III olfactory neuroblastoma completely removed. Although the patient refused the additional radiotherapy, 18 months postoperatively, there were no signs of recurrence, and the patient shows big improvement on her sense of smell.Conclusions
Large olfactory neuroblastomas filling the entire nasal cavity extending back to the postnasal space can be completely removed using a transfacial approach as the Altemir technique modification is. 相似文献36.
37.
Poulakis V Skriapas K de Vries R Dillenburg W Ferakis N Witzsch U Melekos M Becht E 《Asian journal of andrology》2006,8(3):361-366
Aim: To determine retrospectively the safety and efficacy of extracorporeal shock wave therapy (ESWT) in patients with Peyronie's disease. Methods: Fifty-three patients with stable Peyronie's disease underwent ESWT (group 1). Fifteen patients matched with the baseline characteristic of the patients in group 1, who received no treatment, were used as the control (group 2). The patients' erectile function (International Index of Erectile Function [IIEF-5] score), pain severity (visual analog scale), plaque size and degree of penile angulation were assessed before and after the treatment in group 1 and during the follow-up in group 2. Results: The mean follow-up time was 32 months (range: 6-64 months) in group 1 and 35 months (range: 9-48 months) in group 2. All the patients were available for the follow-up. Considering erectile function and plaque size, no significant changes (P 〉 0.05) were observed in group 1 before or after the ESWT. A total of 39 patients (74%) reported a significant effect in pain relief in group 1 after ESWT. However, regarding improvement in pain, IIEF-5 score and plaque size, no significant differences were observed between the two groups. In 21 patients (40%) of group 1, the deviation angle was decreased more than 10° with a mean reduction in all patients of 11° (range: 6-20°). No serious complications were noted considering ESWT procedure. Conclusion: ESWT is a minimally invasive and safe alternative procedure for the treatment of Peyronie's disease. However, the effect of ESWT on penile pain, sexual function and plaque size remains questionable. 相似文献
38.
Georgia Koukiou Vassilis Anastassopoulos 《The Australian journal of forensic sciences》2016,48(3):326-338
In this work, facial thermal infrared images are employed for intoxicated person discrimination. The activity of the facial blood vessels of sober and intoxicated people comes into sight when nonlinear anisotropic diffusion and top-hat transformation are applied to enhance and isolate the vessels from the rest of the information on the face. For an intoxicated person, vessels around the nose and eyes as well as on the forehead become more active, whereas for a person who is sober the vessels’ activity is smoother all over the face’s thermal image. Accordingly, drunkenness can be ascertained by only using the thermal infrared image of the intoxicated person. The proposed method can be incorporated into a non-invasive inspection system used by the police as a first step for intoxicated person detection. The Student’s t-test is employed to assess the degree of confidence in separating the thermal images corresponding to sober and intoxicated people. The 40 participants in the experiment have contributed to the creation of the unique sober–drunk database available on the web. 相似文献
39.
40.
Parkinson's disease (PD) is caused by dopamine (DA) depletion consequent to cell degeneration in the substantia nigra pars compacta (SNc) and the ventral tegmental area (VTA). Although computational analyses of PD have focused on DA depletion in DA-recipient parts of the basal ganglia, there is also extensive DAergic innervation of the frontal and parietal cortex as well as the spinal cord. To understand PD bradykinesia, a comprehensive network model is needed to study how patterns of DA depletion at key cellular sites in the basal ganglia, cortex and spinal cord contribute to disordered neuronal and spinal cord activity and other PD symptoms. We extend a basal ganglia-cortico-spinal circuit for control of voluntary arm movements by incorporating DAergic innervation of cells in the cortical and spinal components of the circuit. The resultant model simulates successfully several of the main reported effects of DA depletion on neuronal, electromyographic (EMG), and movement parameters of PD bradykinesia. 相似文献