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1.
The functional organization of the sensory cortex is constructed to process sensory information based on experience and learning. Importantly, it is plastic so that it can quickly adapt to environmental changes. Because the thalamus gates all ascending information, it is critical to understand how the thalamocortical system contributes to the plasticity of the sensory cortex. We show here that the neuronal receptive field (RF) in the auditory cortex faithfully tends toward the RF of the electrically stimulated auditory thalamic neurons. We characterized the RF of auditory neurons by measuring the best frequency, minimum threshold, bandwidth, RF area, and averaged response magnitude. All these parameters of the cortical RF showed robust changes toward the values of the parameters of the stimulated thalamic neuron following focal thalamic stimulation. Our data suggest that the thalamocortical system possesses intrinsic mechanisms that underlie the input specificity of learning-induced or experience-dependent cortical plasticity.  相似文献   
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AIM: The postoperative pancreatitis was a classical complication in the historical series of primary hyperparathyroidism (HPT), but the causal association was never demonstrated and even recent studies denied it. The aim of this study was to determine the augmentation of postoperative amylasemia, and its possible clinical traduction in patients operated for primary HPT. MATERIAL AND METHODS: Fifty consecutive patients operated for cure of a primary HPT were included in this study. Total amylase, as well as isoenzyme fractions P (pancreatic) and S (salivary), calcium, phosphorus and intact PTH serum concentrations were determined on the days prior and after parathyroidectomy. Fifteen normocalcemic patients operated for secondary HPT constituted the control group. RESULTS: The study deals with 42 female and eight male patients, their mean age was 58.5 years (range 19-89 years). All patients underwent parathyroidectomy for adenoma or hyperplasia. No patient had pancreatitis before parathyroidectomy. Postoperative amylasemia developed in four patients (8%), one with increased total amylase and P fraction, one with only increased total amylase, and two with increased total amylase and S fraction. No patients exhibited abdominal symptoms suggesting acute pancreatitis in the postoperative period. There was no correlation between pre- and post-operative calcium serum levels and pre- and post-operative amylasemia. In the secondary HPT group no significant diminution of the total amylasemia or of P and S fractions were observed. CONCLUSIONS: These results indicate that acute pancreatitis is an exceptional postoperative complication of primary HPT nowadays. The 8% incidence reported in the present study matches the incidence of hyperamylasemia reported postoperatively in non-abdominal or non-parathyroid surgery.  相似文献   
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Objective: To determine if the non-motor sections of the Movement Disorder Society's (MDS) version of the Unified Parkinson's Disease Rating Scale (UPDRS) could supplement the original UPDRS as a patient completed assessment of changes in non-motor symptoms in Parkinson's disease (PD) patients after bilateral subthalamic nucleus (STN) deep brain stimulation (DBS). Methods: Thirty PD patients who underwent bilateral STN DBS were assessed using the total UPDRS and the non-motor sections of the MDS-UPDRS prior to surgery and one year following surgery. This study focuses on non-motor symptoms as assessed by Part I of the UPDRS and Part 1A and 1B of the MDS-UPDRS. Results: One year following surgery, no individual non-motor symptoms or the total mentation score of the UPDRS were significantly changed. In comparison, the MDS-UPDRS showed significant improvements in sleep and urinary problems and a trend towards improvement in anxiety, constipation, daytime sleepiness, fatigue and pain. Conclusions: This study provides evidence that the MDS-UPDRS non-motor sections, when completed by the patients, can supplement the original version of the UPDRS as an effective method of measuring changes in non-motor symptoms after DBS. It also reinforces the benefits of bilateral STN DBS on non-motor symptoms of PD.  相似文献   
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Success in sandwich technique procedures can be achieved through an acceptable bond between the materials. The aim of this study was to compare the effect of 35% phosphoric acid and Er,Cr:YSGG laser on shear bond strength of conventional glass-ionomer cement (GIC) and resin-modified glass-ionomer cement (RMGIC) to composite resin in sandwich technique. Sixty-six specimens were prepared from each type of glass-ionomer cements and divided into three treatment groups as follows: without pretreatment, acid etching by 35% phosphoric acid for 15 s, and 1-W Er,Cr:YSGG laser treatment for 15 s with a 600-μm-diameter tip aligned perpendicular to the target area at a distance of 1 mm from the surface. Energy density of laser irradiation was 17.7 J/cm2. Two specimens in each group were prepared for evaluation under a scanning electron microscope (SEM) after surface treatment and the remainder underwent bonding procedure with a bonding agent and composite resin. Then the shear bond strength was measured at a crosshead speed of 0.5 mm/min. Two-factor analysis of variance and post-hoc Tukey test showed that the cement type, surface treatment method, and the interaction of these two factors significantly affect the shear bond strength between glass-ionomer cements and composite resin (p < 0.05). Surface treatment with phosphoric acid or Er,Cr:YSGG laser increased the shear bond strength of GIC to composite resin; however, in RMGIC only laser etching resulted in significantly higher bond strength. These findings were supported by SEM results. The fracture mode was evaluated under a stereomicroscope at ×20.  相似文献   
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Objectives/BackgroundMedical therapy is the first line of treatment for intracranial atherosclerotic disease (ICAD). Percutaneous transluminal angioplasty and stenting (PTAS) are mainly considered for those patients with severe stenosis and recurrent events despite aggressive medical therapy. In this review, we discuss the application of PTAS as a treatment option for ICAD and its future prospect.Materials and MethodsWe did the literature review of the key articles and guidelines to elaborate on the role of PTAS in the management of ICAD based on the current data and expert opinion. We searched PubMed, Google Scholar, and Scopus up to August 2020, and included articles published only in the English language.ResultsSince the publication of the results from SAMMPRIS and VISSIT trials, stenting is no longer recommended for secondary stroke prevention in patients with symptomatic ICAD. However, recent clinical studies on intracranial stenting for a subgroup of ICAD patients have shown promising results, likely due to better patient selection and continued advancement of endovascular techniques.ConclusionThere exists a lack of consensus regarding the best endovascular treatment approach (e.g., angioplasty alone or balloon mounted stent vs. self-expanding stent with or without prior angioplasty) or management of in-stent restenosis. Another area of clinical controversy relates to the ideal use and duration of antiplatelet therapy.  相似文献   
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Sport Sciences for Health - The widespread prevalence and mortality of coronavirus diseases-2019 (COVID-19) lead many researchers to study the SARS-CoV-s2 infection to find a treatment for this...  相似文献   
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Journal of NeuroVirology - The novel coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has instigated a global pandemic as a formidable...  相似文献   
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Objective:

To investigate the feasibility of using glass beads as novel thermoluminescent dosemeters (TLDs) for radiotherapy treatment plan verification.

Methods:

Commercially available glass beads with a size of 1-mm thickness and 2-mm diameter were characterized as TLDs. Five clinical treatment plans including a conventional larynx, a conformal prostate, an intensity-modulated radiotherapy (IMRT) prostate and two stereotactic body radiation therapy (SBRT) lung plans were transferred onto a CT scan of a water-equivalent phantom (Solid Water®, Gammex, Middleton, WI) and the dose distribution recalculated. The number of monitor units was maintained from the clinical plan and delivered accordingly. The doses determined by the glass beads were compared with those measured by a graphite-walled ionization chamber, and the respective expected doses were determined by the treatment-planning system (TPS) calculation.

Results:

The mean percentage difference between measured dose with the glass beads and TPS was found to be 0.3%, −0.1%, 0.4%, 1.8% and 1.7% for the conventional larynx, conformal prostate, IMRT prostate and each of the SBRT delivery techniques, respectively. The percentage difference between measured dose with the ionization chamber and glass bead was found to be −1.2%, −1.4%, −0.1%, −0.9% and 2.4% for the above-mentioned plans, respectively. The results of measured doses with the glass beads and ionization chamber in comparison with expected doses from the TPS were analysed using a two-sided paired t-test, and there was no significant difference at p < 0.05.

Conclusion:

It is feasible to use glass-bead TLDs as dosemeters in a range of clinical plan verifications.

Advances in knowledge:

Commercial glass beads are utilized as low-cost novel TLDs for treatment-plan verification.  相似文献   
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