Search results for "vision."
showing 10 items of 4900 documents
Focal nodular hyperplasia: typical and atypical MRI findings with emphasis on the use of contrast media
2007
Focal nodular hyperplasia is a benign hypervascular hepatic tumour, frequently detected in asymptomatic patients undergoing imaging studies for unrelated reasons. Magnetic resonance imaging (MRI) generally allows a confident differential diagnosis with other hypervascular liver lesions, either benign or malignant. In addition, due to the recent development of hepatospecific MRI contrast agents, MRI concomitantly enables functional and morphological information to be obtained, thus providing important clues for the detection and characterization of focal nodular hyperplasia lesions.
Influence of the luminance level on visual performance with a disposable soft cosmetic tinted contact lens.
2001
The purpose of the present work was to study the effect on visual performance of wearing disposable soft tinted contact lenses for cosmetic purposes. Parameters such as contrast sensitivity (Vistech 6000), colour vision (Farnsworth-Munsell 100-Hue colour test), visual fields (static Goldmann perimetry) and subjective vision (what the wearer feels while wearing the lenses) were studied under different illumination levels in order to check for possible vision losses while wearing these contact lenses at low illumination levels. Sixteen emmetropic subjects were fitted consecutively with seven pairs of different colour lenses (Optima Colors lenses by BauschLomb), and the experimental parameters…
Effect of cordycepin on interleukin-10 production of human peripheral blood mononuclear cells
2002
Therapeutic options for controlling autoimmune diseases are still very limited. Interleukin-10 has been reported to be a promising approach to therapeutic intervention. In the search for a drug which results in the selective upregulation of interleukin-10, we investigated the immunoregulative effects of cordycepin. We have measured interleukin-10 and interleukin-2 secretion of human peripheral blood mononuclear cells that were incubated with cordycepin and assessed the influence of cordycepin on the expression of interleukin-10 mRNA, the proliferative response and the expression of surface markers on T lymphocytes. In addition, the subsets of interleukin-10-secreting cells, the influence of…
The influence of scene and object orientation on the scene consistency effect
2019
Abstract Contextual regularities help us make sense of our visual environment. In scenes, semantically consistent objects are typically better recognized than inconsistent ones (e.g., a toaster vs. printer in a kitchen). What is the role of object and scene orientation in this so-called scene consistency effect? We presented consistent and inconsistent objects either upright (Experiment 1) or inverted (rotated 180°; Experiment 2) on upright, inverted, and scrambled background scenes. In Experiment 1, on upright scenes, consistent objects were recognized with higher accuracy than inconsistent ones, and we observed N300/N400 event-related potentials (ERPs) reflecting object-scene semantic pro…
Dynamic accommodation without feedback does not respond to isolated blur cues
2016
Highlights • A new methodology is used to study a potential cue for dynamic accommodation. • We show that human accommodation is not driven correctly by defocus alone. • Accommodation is most efficient using changes in stimulus vergence with feedback.
Accommodative Functions with Multifocal Contact Lenses: A Pilot Study
2011
PURPOSE: To evaluate accommodative response and facility in presbyopic patients fitted with several types of simultaneous-image multifocal contact lenses (CLs). METHODS: Six presbyopic patients, unadapted wearers of simultaneous-image bifocals, were fitted with the Focus Progressives and the low- and high-addition Pure Vision simultaneous vision multifocal CLs. Each individual wore each of the three types of lenses in successive random order. Accommodative response, accommodative facility, visual acuity, and contrast sensitivity at distance and near were evaluated in all cases. A control group of eight non-presbyopic patients was also studied. RESULTS: The mean age was 28.6 +/- 2.72 and 51.…
Influence of contrast polarity on the accommodative response☆
2018
espanolObjetivo Evaluar los cambios de la respuesta acomodativa del ojo al leer un texto en diferentes condiciones de polaridad de contraste: letras negras sobre fondo blanco (condicion BoW) y letras blancas sobre fondo negro (condicion WoB). Metodos En este estudio experimental participaron dieciocho sujetos de edades comprendidas entre 21 y 41 anos. Se obtuvo objetivamente la respuesta acomodativa (AR) del ojo al leer un texto con polaridad de contraste BoW o WoB con un sistema de optica adaptativa que corregia todas las aberraciones salvo las propias del sujeto. Se estudiaron dos tamanos de letra diferentes (condiciones de agudeza visual), mostrados en una micropantalla. Se midio la AR d…
Mutation spectrum and clinical investigation of achromatopsia patients with mutations in the GNAT2 gene
2019
Achromatopsia (ACHM) is a hereditary cone photoreceptor disorder characterized by the inability to discriminate colors, nystagmus, photophobia, and low-visual acuity. Six genes have been associated with this rare autosomal recessively inherited disease, including the GNAT2 gene encoding the catalytic α-subunit of the G-protein transducin which is expressed in the cone photoreceptor outer segment. Out of a cohort of 1,116 independent families diagnosed with a primary clinical diagnosis of ACHM, we identified 23 patients with ACHM from 19 independent families with likely causative mutations in GNAT2, representing 1.7% of our large ACHM cohort. In total 22 different potentially disease-causing…
A method of measuring the apical base
1996
SUMMARY The maxillary and mandibular apical base areas were measured, using a gnathograph, on the study casts of 156 adults and children representing Class II division 1, Class II division 2 and Class III malocclusions. There were significant differences between the groups at each age. The maxillary apical base areas tended to be smaller for the adults than for the children in all three occlusal classes. By contrast, the mandibular apical base areas tended to be larger for the adults than for the children, except in Class II division 1 malocclusion. Following a logarithmic transformation to stabilize the variance, regression lines were fitted to relate the size of the maxillary and mandibul…
Prismatic lenses shift time perception
2009
Previous studies have demonstrated the involvement of spatial codes in the representation of time and numbers. We took advantage of a well-known spatial modulation (prismatic adaptation) to test the hypothesis that the representation of time is spatially oriented from left to right, with smaller time intervals being represented to the left of larger time intervals. Healthy subjects performed a time-reproduction task and a time-bisection task, before and after leftward and rightward prismatic adaptation. Results showed that prismatic adaptation inducing a rightward orientation of spatial attention produced an overestimation of time intervals, whereas prismatic adaptation inducing a leftward…