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People differ in their ability to perform novel perceptual tasks, both during initial exposure and in the rate of improvement with practice. It is also known that regions of the brain recruited by particular tasks change their activity during learning. Here we investigate neural signals predictive of individual variability in performance. We used resting-state functional MRI to assess functional connectivity before training on a novel visual discrimination task. Subsequent task performance was related to functional connectivity measures within portions of visual cortex and between visual cortex and prefrontal association areas. Our results indicate that individual differences in performing novel perceptual tasks can be related to individual differences in spontaneous cortical activity.  相似文献   
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The aim of this study was to assess exercise test results and efficacy of therapy with a β blocker (acebutolol) in ryanodine receptor type 2 (RyR2) mutation carriers with documented ventricular arrhythmias (VAs) and long-term follow-up. Twenty RyR2 mutation carriers belonging to 8 families and regularly followed at our center were analyzed using a study protocol involving electrocardiography, exercise tests off and on β-blocker therapy, 2-dimensional echocardiography, and signal-averaged electrocardiography. Off-therapy exercise testing triggered the onset of VAs at different heart rates (mean 132 ± 13 beats/min) with various patterns that worsened while exercising and disappeared immediately after stopping. The most severe VAs detected were nonsustained ventricular tachycardia in 35% and ventricular couplets in 35%. In the remaining subjects single ventricular premature beats were recorded. In 15% of patients single monomorphic ventricular premature beats were detected and identified to be linked to RyR2 mutations owing to the presence of sudden deaths of their family members and subsequent family screening. Acebutolol made the VAs disappear completely in 20% of subjects and decreased their complexity in 50%, whereas it did not change VAs appreciably in 30% of patients with less complex VAs. After 11 ± 8 years of follow-up 2 patients developed syncope. In conclusion, exercise testing was a fundamental tool for assessing the clinical phenotype and efficacy of therapy in RyR2 mutation carriers and therapy with acebutolol led in most subjects to a decreased complexity of the arrhythmic pattern or to complete suppression.  相似文献   
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The aim of this review is to evaluate the use of chemotherapy (CT) in the treatment of squamous vulvar cancer. Since the 90s there was a continuous evolution in the therapeutic approach to this tumour. Although primary surgery is now considered the most effective approach, there are advanced diseases in which surgery may compromise anatomical structures causing severe mutilation. These are the reasons why CHT, with or without concomitant radiotherapy RT, started to be strongly recommended as neoadjuvant strategy. Chemotherapeutic agents have also been used alone as adjuvant treatment or in association with RT, by exploiting the radiosensitizing effect of these drugs. There are few data about the use of CHT as palliative treatment but recent studies point to the use of target therapy. In conclusion, clinical data and the evidence of chemo-sensitivity in vulvar squamous cell carcinoma open new possibilities to future research in this field.  相似文献   
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Individuals with schizophrenia experience problems in the perception of emotion throughout the course of the disorder. Few studies have addressed the progression of the deficit over time. The present investigation explores face emotion recognition (FER) performance throughout the course of schizophrenia. The aim of the study was to test the hypotheses that: 1) FER impairment was present in ultra high-risk (putatively prodromal) individuals, and that 2) impairment was stable across the course of the illness. Forty-three individuals with a putative prodromal syndrome, 50 patients with first episode of schizophrenia, 44 patients with multi-episode schizophrenia and 86 unaffected healthy control subjects were assessed to examine emotion recognition ability. ANCOVA analysis adjusted for possible confounder factors and subsequent planned contrasts with healthy controls was undertaken. The results revealed deficits in recognition of sadness and disgust in prodromal individuals, and of all negative emotions in both first-episode and multi-episode patients. Furthermore, there were no significant differences between clinical groups. Within the framework of the neurodevelopmental model of schizophrenia, our results suggest the presence of emotional recognition impairment before the onset of full-blown psychosis. Moreover, the deficit remains stable over the course of illness, fitting the pattern of a vulnerability indicator in contrast to an indicator of chronicity or severity.  相似文献   
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Introduction: Colloidal drug delivery systems (CDDSs) are innovative carriers that have been studied in pharmaceutical field from many years to overcome unfavorable physical and chemical features of synthetic drugs. Recently the use of CDDS as carriers for phytochemicals has seen an exponential increase which, in some cases, has led to the rediscovery of ancient and forgotten natural molecules.

Area covered: This article focuses on the main features of CDDS, particularly micro- and nanoemulsions, vesicular carriers and micro- and nanoparticles, loaded with natural active compounds. A detailed review of the literature is presented, introducing the importance of these systems in terms of their capability to optimize the stability of phytochemicals, their absorption through biological membranes and their bioavailability.

Expert opinion: The delivery of phytochemicals is problematic due to poor solubility, poor permeability, low bioavailability, instability in biological milieu and extensive first-pass metabolism. Global research efforts investigating nanotechnology have attempted to overcome these limitations rediscovering and, in some cases, ‘discovering ex novo’ unexpected virtues and benefits associated to these compounds. The ‘nanotechnological approach’ can definitely enhance the pharmacokinetics and therapeutic index of natural active compounds and improve their performance in therapy.  相似文献   

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Journal of Neurology - Compression of the median nerve at the carpal tunnel can give demyelinating features and result in distal motor latency (DML) prolongation fulfilling the EFNS/PNS...  相似文献   
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