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981.
Background
High frequency transcranial random noise stimulation (hf-tRNS) facilitates performance in several perceptual and cognitive tasks, however, little is known about the underlying modulatory mechanisms.Objective
In this study we compared the effects of hf-tRNS to those of anodal and cathodal tDCS in a global motion direction discrimination task. An equivalent noise (EN) paradigm was used to assess how hf-tRNS modulates the mechanisms underlying local and global motion processing.Method
Motion coherence threshold and slope of the psychometric function were estimated using an 8AFC task in which observers had to discriminate the motion direction of a random dot kinematogram presented either in the left or right visual hemi-field. During the task hf-tRNS, anodal and cathodal tDCS were delivered over the left hMT+. In a subsequent experiment we implemented an EN paradigm in order to investigate the effects of hf-tRNS on the mechanisms involved in visual motion integration (i.e., internal noise and sampling).Results
hf-tRNS reduced the motion coherence threshold but did not affect the slope of the psychometric function, suggesting no modulation of stimulus discriminability. Anodal and cathodal tDCS did not produce any modulatory effects. EN analysis in the last experiment found that hf-tRNS modulates sampling but not internal noise, suggesting that hf-tRNS modulates the integration of local motion cues.Conclusion
hf-tRNS interacts with the output neurons tuned to directions near to the directional signal, incrementing the signal-to-noise ratio and the pooling of local motion cues and thus increasing the sensitivity for global moving stimuli. 相似文献982.
983.
Ylenia Duca Aldo E. Calogero Rossella Cannarella Filippo Giacone Laura M. Mongioi Rosita A. Condorelli Sandro La Vignera 《Andrologia》2019,51(5)
Erectile dysfunction could be an early sign of endothelial dysfunction and, therefore, of cardiovascular disease, with which it shares many risk factors. Among reversible risk factors, physical inactivity is one of the most important. Regular physical exercise has been shown to improve erectile function through different mechanisms involving glucose and lipid metabolism, regulation of arterial pressure, production of nitric oxide and hormonal modulation. Furthermore, exercise shows a synergistic effect with the drugs commonly used in the treatment of impotence. Since many patients with erectile dysfunction may have underlying cardiovascular disease, the evaluation of individual cardiovascular risk is mandatory before prescribing physical exercise. When exercise is not contraindicated, the most appropriate protocol must be chosen, considering the individual characteristics of the patient. Both aerobic and anaerobic/resistance protocols have proven effective. However, meta‐analytic studies show that aerobic exercise with moderate‐to‐vigorous intensity is the most effective in improving erection. Testosterone is an important modulator of physical performance, and its blood levels must always be evaluated in patients with erectile dysfunction. 相似文献
984.
Lorenzo Nicolè MD Filippo Cappello MS Rocco Cappellesso MD PhD Christopher J. VandenBussche MD PhD Ambrogio Fassina MD 《Cancer cytopathology》2019,127(8):493-500
The cytomorphologic evaluation of serous cavity specimens can quickly determine the cause of an effusion as well as the presence or absence of a neoplastic process. Ancillary tests such as immunohistochemistry and fluorescence in situ hybridization are frequently used to help to definitively identify malignant cells, determine a site of origin, and distinguish between malignant and reactive mesothelial proliferations. In recent years, microRNAs (miRNAs) have been increasingly evaluated in cytologic specimens, including those from serous cavities. The examination of miRNA is attractive because of the stability of miRNA in such specimens and data suggesting that miRNA can provide prognostic and therapeutic information in addition to its role in diagnosis. Furthermore, miRNAs exist within extracellular exosomes, and this allows for their analysis in specimens that contain only rare malignant cells, degenerated cells, or obscuring components. This review discusses the technical aspects of specimen processing for miRNA analysis, recent studies of miRNA expression in malignant serous cavity specimens, and the potential importance of miRNA expression analysis for serous cavity specimens in the near future. 相似文献
985.
986.
987.
Andrea Vergallo Cecilia Carlesi Cristina Pagni Filippo Sean Giorgi Filippo Baldacci Lucia Petrozzi Roberto Ceravolo Gloria Tognoni Gabriele Siciliano Ubaldo Bonuccelli 《Neurological sciences》2017,38(10):1791-1797
Abnormal levels of beta amyloid (Aβ42) and tau protein concentrations in the cerebral spinal fluid (CSF) have been largely described in Alzheimer’s disease (AD). Thus, CSF analysis of these biomarkers has been incorporated in recent AD diagnostic criteria, and it is increasingly performed for neurodegenerative dementia diagnostic workout in clinical setting. Nevertheless, the precise biomarkers CSF features in neurodegenerative dementia, either AD or Frontotemporal dementia (FTD), are still not fully clear today. This is mainly due to lack of CSF clear cutoff values due to a well-known intersite (but even intrasite) variability of CSF procedures, ranging from collection to analysis. Applying CSF biomarker ratios, rather than their single values could represent a useful tool, especially for the differential diagnosis of different forms of dementia. We explored clinical values of six CSF ratios (by combining Aβ42 and tau) in order to better discriminate between AD and FTD; we identified Aβ42/p-Tau181 ratio as a potential good candidate for helping differentiating AD from FTD in the clinical practice. 相似文献
988.
Rosario Mazzola Pierpaolo Alongi Francesco Ricchetti Alba Fiorentino Sergio Fersino Niccolò Giaj-Levra Matteo Salgarello Filippo Alongi 《La Radiologia medica》2017,122(12):952-959
Aim
To analyze the impact of 18F-fluorodeoxyglucose-PET/CT (PET/CT) in the radiotherapy (RT) planning strategy in HNC, correlating CT-scan and PET/CT performances.Materials and methods
Inclusion criteria were: age >18 years old, histologically proven head and neck cancer (HNC), patients candidate to definitive RT ± chemotherapy, stage of disease by means of PET/TC and CT-scan performed at our Cancer Care Center.Results
Sixty patients were analyzed. The following primary tumor sites were investigated: nasopharynx (13%), oropharynx (42%), oral cavity (32%) and larynx non-glottic (13%). Globally, PET/CT findings caused changes on nodal radiation treatment volumes in 10% of all the population of study. Specifically, in 5 cases out of 19 oral cavity tumors (26%), PET/CT detected neck-nodes positive (not detected at CT-scan). These findings have allowed to change the patients management, including PET/CT neck-nodes positive in the high-risk RT volumes.Conclusion
In the RT planning strategy, the present findings support the use of PET/CT to improve upfront regional staging of HNC disease, particularly for oral cavity tumors. Further investigations are advocated to evaluate if this strategy could impact on long-term outcomes in terms of local control and overall survival.989.
Anna Maria Ierardi Francesca Giorlando Filippo Piacentino Federico Fontana Raffaele Novario Salvatore Alessio Angileri Ejona Duka Gianpaolo Carrafiello 《La Radiologia medica》2017,122(2):81-87
Purpose
The aim of our study was to evaluate factors influencing effectiveness of percutaneous microwave ablation (MWA) in patients with small hepatocellular carcinoma (HCC) (<3 cm).Materials and methods
Between December 2007 and August 2015, 49 patients with 65 previously histological typed HCC were treated in a total of 61 sessions. Tumours were subdivided into central (>3 cm from the capsule) (n = 22) and peripheral (<3 cm from the capsule) (n = 43). Imaging follow-up was performed at 1, 3, 6, and 12 months after treatment, then annually. Mean follow-up period was 18 months (range 1–55). Location of the lesion, age, sex, and underlying disease of the patients was analyzed and related with efficacy.Results
Technical success was obtained in all cases. Residual disease was registered in 21 lesions (32.3 %): 13 were peripheral and 8 were central. Twelve of them were retreated with percutaneous MWA. Local recurrence was recorded in 8 lesions (12.3 %): 5 were retreated with MWA. No significant difference in terms of effectiveness was observed in lesions located in a central position and those situated in the peripheral position. Age, sex, and underlying disease not influenced results. Only one major complication was observed. The rate of minor complications was 24.5 %. Mortality at 30 days was 0 %.Conclusions
Our results encourage the role of MWA in the treatment of small HCC. More numerous series and randomized studies are necessary to state the role of MWA and to select cases in which MWA may be more effective and safer than RFA.990.
Rosa Capozzo Celeste Sassi Monia B. Hammer Simona Arcuti Chiara Zecca Maria R. Barulli Rosanna Tortelli J. Raphael Gibbs Cynthia Crews Davide Seripa Francesco Carnicella Claudia DellAquila Marco Rossi Filippo Tamma Francesco Valluzzi Bruno Brancasi Francesco Panza Andrew B. Singleton Giancarlo Logroscino 《Alzheimer's & dementia》2017,13(8):858-869