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排序方式: 共有4470条查询结果,搜索用时 31 毫秒
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Caterina Montani Carola Canella Adam J. Schwarz Jennifer Li Gary Gilmour Alberto Galbusera Keith Wafford Daniel Gutierrez-Barragan Andrew McCarthy David Shaw Karen Knitowski David McKinzie Alessandro Gozzi Christian Felder 《Neuropsychopharmacology》2021,46(6):1194
Cholinergic drugs acting at M1/M4 muscarinic receptors hold promise for the treatment of symptoms associated with brain disorders characterized by cognitive impairment, mood disturbances, or psychosis, such as Alzheimer’s disease or schizophrenia. However, the brain-wide functional substrates engaged by muscarinic agonists remain poorly understood. Here we used a combination of pharmacological fMRI (phMRI), resting-state fMRI (rsfMRI), and resting-state quantitative EEG (qEEG) to investigate the effects of a behaviorally active dose of the M1/M4-preferring muscarinic agonist xanomeline on brain functional activity in the rodent brain. We investigated both the effects of xanomeline per se and its modulatory effects on signals elicited by the NMDA-receptor antagonists phencyclidine (PCP) and ketamine. We found that xanomeline induces robust and widespread BOLD signal phMRI amplitude increases and decreased high-frequency qEEG spectral activity. rsfMRI mapping in the mouse revealed that xanomeline robustly decreased neocortical and striatal connectivity but induces focal increases in functional connectivity within the nucleus accumbens and basal forebrain. Notably, xanomeline pre-administration robustly attenuated both the cortico-limbic phMRI response and the fronto-hippocampal hyper-connectivity induced by PCP, enhanced PCP-modulated functional connectivity locally within the nucleus accumbens and basal forebrain, and reversed the gamma and high-frequency qEEG power increases induced by ketamine. Collectively, these results show that xanomeline robustly induces both cholinergic-like neocortical activation and desynchronization of functional networks in the mammalian brain. These effects could serve as a translatable biomarker for future clinical investigations of muscarinic agents, and bear mechanistic relevance for the putative therapeutic effect of these class of compounds in brain disorders.Subject terms: Schizophrenia, Translational research, Preclinical research 相似文献
33.
Recurrent NAB2–STAT6 gene fusions and oestrogen receptor‐α expression in pulmonary adenofibromas
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![点击此处可从《Histopathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Nicola Fusco Elena Guerini‐Rocco Claudia Augello Andrea Terrasi Giulia Ercoli Caterina Fumagalli Davide Vacirca Paola Braidotti Antonina Parafioriti Marta Jaconi Letterio Runza Vijayalakshmi Ananthanarayanan Fabio Pagni Silvano Bosari Massimo Barberis Stefano Ferrero 《Histopathology》2017,70(6):906-917
34.
Sabina Luisa Campanelli Giuseppe Casalino Caterina Casavola Vincenzo Moramarco 《Materials》2013,6(12):5923-5941
Friction Stir Welding (FSW) is a solid-state joining process; i.e., no melting occurs. The welding process is promoted by the rotation and translation of an axis-symmetric non-consumable tool along the weld centerline. Thus, the FSW process is performed at much lower temperatures than conventional fusion welding, nevertheless it has some disadvantages. Laser Assisted Friction Stir Welding (LAFSW) is a combination in which the FSW is the dominant welding process and the laser pre-heats the weld. In this work FSW and LAFSW tests were conducted on 6 mm thick 5754H111 aluminum alloy plates in butt joint configuration. LAFSW is studied firstly to demonstrate the weldability of aluminum alloy using that technique. Secondly, process parameters, such as laser power and temperature gradient are investigated in order to evaluate changes in microstructure, micro-hardness, residual stress, and tensile properties. Once the possibility to achieve sound weld using LAFSW is demonstrated, it will be possible to explore the benefits for tool wear, higher welding speeds, and lower clamping force. 相似文献
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Folliculotropism in pigmented facial macules: Differential diagnosis with reflectance confocal microscopy
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![点击此处可从《Experimental dermatology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Flavia Persechino Nathalie De Carvalho Silvana Ciardo Barbara De Pace Alice Casari Johanna Chester Shaniko Kaleci Ignazio Stanganelli Caterina Longo Francesca Farnetani Giovanni Pellacani 《Experimental dermatology》2018,27(3):227-232
Pigmented facial macules are common on sun damage skin. The diagnosis of early stage lentigo maligna (LM) and lentigo maligna melanoma (LMM) is challenging. Reflectance confocal microscopy (RCM) has been proven to increase diagnostic accuracy of facial lesions. A total of 154 pigmented facial macules, retrospectively collected, were evaluated for the presence of already‐described RCM features and new parameters depicting aspects of the follicle. Melanocytic nests, roundish pagetoid cells, follicular infiltration, bulgings from the follicles and many bright dendrites and infiltration of the hair follicle (ie, folliculotropism) were found to be indicative of LM/LMM compared to non‐melanocytic skin neoplasms (NMSNs), with an overall sensitivity of 96% and specificity of 83%. Concerning NMSNs, solar lentigo and lichen planus‐like keratosis resulted better distinguishable from LM/LMM because usually lacking malignant features and presenting characteristic diagnostic parameters, such as epidermal cobblestone pattern and polycyclic papillary contours. On the other hand, distinction of pigmented actinic keratosis (PAK) resulted more difficult, and needing evaluation of hair follicle infiltration and bulging structures, due to the frequent observation of few bright dendrites in the epidermis, but predominantly not infiltrating the hair follicle (estimated specificity for PAK 53%). A detailed evaluation of the components of the folliculotropism may help to improve the diagnostic accuracy. The classification of the type, distribution and amount of cells, and the presence of bulging around the follicles seem to represent important tools for the differentiation between PAK and LM/LMM at RCM analysis. 相似文献
38.
Neurological symptoms in essential thrombocythemia: impact of JAK2V617F mutation and response to therapy
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![点击此处可从《European journal of haematology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Andrea Aroldi Caterina Cecchetti Arianna Colombo Leonardo Cattaneo Pietro Enrico Pioltelli Enrico Maria Pogliani Elena Maria Elli 《European journal of haematology》2016,96(6):593-601
Patients with essential thrombocythemia (ET) often suffer from neurological symptoms (NS) not ever resulting from previous thrombotic cerebral events (TCE). We reported NS occurred in 282 patients, in order to identify the factors influencing ET‐related NS in the absence of TCE, and the response to therapy. Overall, 116 of 282 patients (41%) presented NS; 101 of them (87%) reported subjective transient and fluctuating NS, without concurrent TCE, which we defined as ET‐related NS, by frequency: cephalalgia, chronic paresthesias, dizziness or hypotension, visual disturbances, and tinnitus. In univariate analysis, ET‐related NS resulted more frequently in young people (P = 0.017) and in females (P = 0.025). We found a higher prevalence of JAK2V617F mutation in ET‐related NS patients (P = 0.021). In multivariate analysis, gender (P = 0.024) and JAK2V617F mutation (P = 0.041) remained significantly associated with the development of ET‐related NS, with a risk of about four times higher for JAK2V617F‐mutated patients (OR = 3.75). Ninety‐seven of 101 patients with ET‐related NS received an antiplatelet (AP) agent at the time of NS, whereas only selected high‐risk ET‐related NS patients were treated with a cytoreductive drug, according to the published guidelines and similarly to patients without NS. We observed that only 32 of 97 (33%) patients with ET‐related NS achieved a complete response after AP treatment. Among the 65 non‐responder patients, 36 (55.4%) improved NS after the introduction of cytoreductive therapy; therefore, the addition of cytoreductive treatment should be considered in this setting. 相似文献
39.
Maria Pia Villa Alessandra Rizzoli Silvia Miano Caterina Malagola 《Sleep & breathing》2011,15(2):179-184
Purpose
In view of the positive outcome of orthodontic treatment using rapid maxillary expansion (RME) on sleep-disordered breathing, we generated data on RME in children with obstructive sleep apnea (OSA) by evaluating objective and subjective data over a 36-month follow-up period, to determine whether RME is effective in the long-term treatment of OSA. We selected all patients with dental malocclusions and OSA syndrome (OSAS) confirmed by polysomnography. 相似文献40.
Inflammatory bowel disease in chronic granulomatous disease: An emerging problem over a twenty years' experience
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![点击此处可从《Pediatric allergy and immunology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Giulia Angelino Paola De Angelis Simona Faraci Francesca Rea Erminia Francesca Romeo Filippo Torroni Renato Tambucci Alessia Claps Paola Francalanci Maria Chiriaco Gigliola Di Matteo Caterina Cancrini Paolo Palma Patrizia D'Argenio Luigi Dall'Oglio Paolo Rossi Andrea Finocchi 《Pediatric allergy and immunology》2017,28(8):801-809