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71.
The implicit and explicit processing of pairs of line drawings segregated from a ground by low luminance contrast or by high isoluminant colour contrast was assessed in a group of 13 consecutive patients with left unilateral neglect. Left-side differences between the two figures were recognised far less frequently than were right-side differences. Low luminance contrast worsened the explicit recognition of left-side differences. However, when left-side differences were not explicitly recognised, statistically significant implicit processing was found for high colour contrast trials both in the group of patients and in four individual cases. With low luminance contrast trials, implicit processing was found in only one individual case and was not found in the group of patients. A control experiment showed that normal subjects can discriminate the left or the right side of low luminance contrast stimuli with 90 accuracy, while fixating the opposite extremity of stimuli. The results of the present study show that, in patients with left unilateral neglect, implicit processing can be compromised by difficult preattentive discriminability of stimuli and are in keeping with: 1 Farah's 1994a proposal that visual awareness may be related to the quality of visual inputrepresentation in the brain; 2 Spinelli and co-workers' Spinelli, Angelelli, De Luca, & Burr, 1996; Spinelli, Burr, & Morrone, 1994 proposal that patients with left unilateral neglect may suffer from unilateral impaired functioning of the magnocellular pathway, which has high sensitivity to low luminance contrast. 相似文献
72.
Annals of Surgical Oncology - 相似文献
73.
74.
Alessandro Alabastri Salvatore Tuccio Andrea Giugni Andrea Toma Carlo Liberale Gobind Das Francesco De Angelis Enzo Di Fabrizio Remo Proietti Zaccaria 《Materials》2013,6(11):4879-4910
In this paper, we review the principal theoretical models through which the dielectric function of metals can be described. Starting from the Drude assumptions for intraband transitions, we show how this model can be improved by including interband absorption and temperature effect in the damping coefficients. Electronic scattering processes are described and included in the dielectric function, showing their role in determining plasmon lifetime at resonance. Relationships among permittivity, electric conductivity and refractive index are examined. Finally, a temperature dependent permittivity model is presented and is employed to predict temperature and non-linear field intensity dependence on commonly used plasmonic geometries, such as nanospheres. 相似文献
75.
Luca Borrelli Alessandro Fioretti Tamara Pasqualina Russo Lisa Barco Pasquale Raia Luigi Maria De Luca Bossa 《Avian pathology》2013,42(4):323-326
Forty common swifts (Apus apus), synanthropic birds living in an urban environment closely with humans and other animals, were hospitalized in the public veterinary hospital of the Regional Reference Center of Urban Veterinary Hygiene located in Naples, Campania Region, Italy. Each bird was sampled for bacteriological analyses. Out of 40 common swifts examined, eight were found positive for Salmonella enterica serovar Infantis although no sign of salmonellosis (e.g. diarrhoea) was shown. This is believed to be the first report of Salmonella spp. infection in common swifts. Our results suggest this avian species as a novel potential reservoir for one of most important Salmonella serovars. 相似文献
76.
Abigail B. Diack Diane Ritchie Matthew Bishop Victoria Pinion Jean-Philippe Brandel Stephane Haik Fabrizio Tagliavini Cornelia Van Duijn Ermias D. Belay Pierluigi Gambetti Lawrence B. Schonberger Pedro Piccardo Robert G. Will Jean C. Manson 《Emerging infectious diseases》2012,18(10):1574-1579
Variant Creutzfeldt-Jakob disease (vCJD) has been reported in 12 countries. We hypothesized that a common strain of agent is responsible for all vCJD cases, regardless of geographic origin. To test this hypothesis, we inoculated strain-typing panels of wild-type mice with brain material from human vCJD case-patients from France, the Netherlands, Italy, and the United States. Mice were assessed for clinical disease, neuropathologic changes, and glycoform profile; results were compared with those for 2 reference vCJD cases from the United Kingdom. Transmission to mice occurred from each sample tested, and data were similar between non-UK and UK cases, with the exception of the ranking of mean clinical incubation times of mouse lines. These findings support the hypothesis that a single strain of infectious agent is responsible for all vCJD infections. However, differences in incubation times require further subpassage in mice to establish any true differences in strain properties between cases. 相似文献
77.
Manuele Casale Emanuela Vesperini Massimiliano Potena Marco Pappacena Federica Bressi Peter Jarden Baptista Fabrizio Salvinelli 《Sleep & breathing》2012,16(2):413-417
Purpose
The transduction mechanism of the inner ear and the transmission of nerve impulses along the auditory way are highly dependent upon the cochlear oxygen supply. Several studies have considered the possibility that obstructive sleep apnea–hypopneas during sleep can interfere with these processes, and the results are not uniform. The aim of the study is to evaluate the auditory function in adult patients affected by severe obstructive sleep apnea syndrome (OSAS). 相似文献78.
Sara Proietti Alessandra Cucina Gabriella Dobrowolny Fabrizio D'Anselmi Simona Dinicola Maria Grazia Masiello Alessia Pasqualato Alessandro Palombo Veronica Morini Russel J. Reiter Mariano Bizzarri 《Journal of pineal research》2014,57(1):120-129
Compelling evidence demonstrated that melatonin increases p53 activity in cancer cells. p53 undergoes acetylation to be stabilized and activated for driving cells destined for apoptosis/growth inhibition. Over‐expression of p300 induces p53 acetylation, leading to cell growth arrest by increasing p21 expression. In turn, p53 activation is mainly regulated in the nucleus by MDM2. MDM2 also acts as E3 ubiquitin ligase, promoting the proteasome‐dependent p53 degradation. MDM2 entry into the nucleus is finely tuned by two different modulations: the ribosomal protein L11, acts by sequestering MDM2 in the cytosol, whereas the PI3K‐AkT‐dependent MDM2 phosphorylation is mandatory for MDM2 translocation across the nuclear membrane. In addition, MDM2‐dependent targeting of p53 is regulated in a nonlinear fashion by MDM2/MDMX interplay. Melatonin induces both cell growth inhibition and apoptosis in MCF7 breast cancer cells. We previously reported that this effect is associated with reduced MDM2 levels and increased p53 activity. Herein, we demonstrated that melatonin drastically down‐regulates MDM2 gene expression and inhibits MDM2 shuttling into the nucleus, given that melatonin increases L11 and inhibits Akt‐PI3K‐dependent MDM2 phosphorylation. Melatonin induces a 3‐fold increase in both MDMX and p300 levels, decreasing simultaneously Sirt1, a specific inhibitor of p300 activity. Consequently, melatonin‐treated cells display significantly higher values of both p53 and acetylated p53. Thus, a 15‐fold increase in p21 levels was observed in melatonin‐treated cancer cells. Our results provide evidence that melatonin enhances p53 acetylation by modulating the MDM2/MDMX/p300 pathway, disclosing new insights for understanding its anticancer effect. 相似文献
79.
Mariangela Lopopolo Giannapia Affaitati Alessandra Fabrizio Francesca Massimini Domenico Lapenna Maria Adele Giamberardino Raffaele Costantini 《Fundamental & clinical pharmacology》2014,28(3):331-341
The effects of tramadol versus placebo administration on behavioral indicators of ureteral pain, pelvic pain and referred lumbar muscle hyperalgesia were investigated in a rat model of viscero‐visceral hyperalgesia from endometriosis plus ureteral calculosis (endo + stone). Fifty female Sprague‐Dawley rats underwent surgical induction of endometriosis and, 2 weeks later, were randomly assigned to five groups (10 each), to be treated i.p., twice a day, with tramadol (0.625, 1.25, 2.5, or 5 mg/kg) or saline for 5 days (14–18th day postendometriosis; prestone treatment). On the 21st day, they underwent laparotomy for stone formation in the upper left ureter (dental cement injection). All were video‐taped 24 h nonstop for 7 days before and 4 days after stone formation (14–25th day postendometriosis) to record ureteral and pelvic pain behaviors. Lumbar sensitivity (L1) was tested bilaterally, daily over the same period, by verifying presence/absence of vocalization upon muscle pinching at a predefined pressure (calibrated forceps). Additional fifty endo + stone rats underwent the same protocol, except that treatment was performed on 21st–25th day (poststone treatment). Tramadol vs. saline significantly reduced number and duration of ureteral crises, duration of pelvic behavior, and incidence of muscle hyperalgesia (P < 0.0001), with a dose‐dependent effect. Prestone treatment was significantly more effective than poststone treatment for the 1.25 dose for all parameters and 2.5 dose for pelvic and muscle parameters (0.003 > P < 0.02). Tramadol, even at low doses, is thus highly protective against pain from ‘viscero‐visceral hyperalgesia’ in endometriosis plus ureteral calculosis; it can represent a valid therapeutic approach in women with these comorbidities. 相似文献
80.