Search results for "Sensor"
showing 10 items of 4594 documents
Effects of contralateral white noise stimulation on transitory evoked otoacoustic emissions in patients with acoustic neuroma.
1995
Abstract Transitory evoked otoacoustic emissions are normal phenomena observed in most persons with hearing levels greater than 35 dB. Further, masking of the contralateral ear produces amplitude reductions in the transitory evoked otoacoustic emissions. We have undertaken a study of transitory evoked otoacoustic emissions in 20 patients with acoustic neuroma. All patients were assessed for transitory evoked otoacoustic emissions bilaterally, with and without contralateral masking with white band noise at 40, 50, and 60 dB. We found that transitory evoked otoacoustic emissions were present in 30% of ears with tumor and that the presence of transitory evoked otoacoustic emissions is associat…
Collagen copolymer posterior chamber phakic intraocular lens for hyperopia correction: three-year follow-up.
2013
Purpose To assess the efficacy, predictability, safety, and stability of the Visian V3 Implantable Collamer Lens posterior chamber phakic intraocular lens (PC pIOL) for moderate to high hyperopia. Setting Private clinic, Oviedo, Spain. Design Prospective nonrandomized clinical study. Methods The uncorrected (UDVA) and corrected (CDVA) distance visual acuities, manifest refraction, endothelial cell density, intraocular pressure (IOP), central vault, and adverse events were evaluated for 3 years postoperatively. Results The study comprised 73 eyes of 44 patients. The mean spherical equivalent decreased from +4.84 diopters (D) ± 1.6 (SD) (range +1.00 to +7.75 D) preoperatively to −0.13 ± 0.39 …
Attention to pain is processed at multiple cortical sites in man.
2004
Painful cutaneous laser stimuli evoked potentials (LEPs) were recorded over the primary somatosensory (SI), parasylvian, and medial frontal (MF) cortex areas in a patient with subdural electrode grids located over these areas for surgical treatment of epilepsy. The amplitudes of the negative (N2*) and positive (P2**) LEP peaks over SI, parasylvian, and MF cortex were enhanced by attention to (counting stimuli), in comparison with distraction from the stimulus (reading for comprehension). Late positive deflections following the P2** peak (late potential—LP) were recorded over MF and from the lateral premotor regions during attention but not during distraction. These findings suggest that att…
Vascular modifications within a choroidal osteoma
1993
We report a case of choroidal osteoma followed-up for 7 years. During this lapse of time the choroidal osteoma showed slight enlargement, development of subretinal hemorrhage and modifications of intratumoral vascularization. Some large intratumoral vessels visible at first examination disappeared at follow-up, while other vessels not observed before developed. The changes in the vascularization of the choroidal osteoma denote profound dynamics in the processes of osseous rearrangement of the tumor.
Impaired refractory periods of peripheral sensory nerves in multiple sclerosis.
1978
Maximum conduction velocity and relative refractory period (RRP) of median nerve sensory fibers were studied in 36 patients diagnosed as having multiple sclerosis (MS) and in 31 controls. Maximum conduction velocity did not differ in the two groups, but the RRP was significantly prolonged in MS patients. Increased RRP is observed mainly when peripheral nerve myelin is abnormal or damaged. Our findings support the assumption that peripheral nerve myelinated fibers are usually involved in MS.
Capsular bag shrinkage after implantation of a capsular bending or capsular tension ring.
2005
To evaluate the influence of a capsular bending ring (CBR) or tension ring (CTR) on capsular bag shrinkage.Department of Ophthalmology, Johannes Gutenberg-University, and Department of Medical Biometry, Epidemiology and Informatics, University of Mainz, Mainz, Germany.In 92 eyes of 92 patients, a capsular measuring ring (CMR) was implanted after phacoemulsification to measure capsular bag size in vivo. Patients were randomized into 3 groups: The first received a CMR and CBR, the second received a CMR and CTR, and the third received a CMR alone. Measurements were performed preoperatively, intraoperatively, during the first 3 postoperative days, and after 1 and 3 months. Preoperative biometri…
Physical Activity, Incidence, and Progression of Age-Related Macular Degeneration: A Multicohort Study.
2022
Contains fulltext : 249581.pdf (Publisher’s version ) (Closed access) PURPOSE: To investigate the impact of physical activity (PA) on the incidence or progression of age-related macular degeneration (AMD) in the general population. DESIGN: Meta-analysis of longitudinal cohort studies. METHODS: We included 14,630 adults with no or early AMD at baseline from 7 population-based studies and examined associations of PA with AMD incidence and progression using multistate models (MSM) per study and subsequent random effects meta-analysis. Age effects were assessed using meta-regression. The main outcome measure was the hazard ratio (HR) for incident early or progression to late AMD. RESULTS: At ba…
Contrast sensitivity after implantation of toric iris-claw lenses in phakic eyes.
2004
Abstract Purpose: To evaluate the change in contrast sensitivity after implantation of the Verisyse toric phakic intraocular lens (IOL) (AMO) for the correction of myopia with astigmatism. Setting: Department of Ophthalmology, Johannes Gutenberg-University, Mainz, Germany. Methods: Eighteen eyes had implantation of an iris-supported toric phakic IOL to correct myopia with astigmatism. The mean preoperative spherical equivalent was −12.65 diopters ± 3.6 (SD). The contrast sensitivity with best spectacle correction was determined before surgery and 3 months after surgery using the CSV-1000 HGT instrument (Vector Vision Inc.). Results: Three months after IOL implantation, the mean contrast sen…
Perceptual and response bias in visuospatial neglect due to frontal and parietal repetitive transcranial magnetic stimulation in normal subjects.
2002
Recently some authors have challenged the conventional association of directional motor neglect with damage of frontal structures, showing that pure sensory perceptual neglect (classically associated with parietal lesion) can follow damage of right frontal cortex. The aim of the present study was to assess the type of defect in visuo-spatial attention consequent upon a virtual frontal or parietal lesion induced by transcranial magnetic stimulation in normal subjects. To this purpose eleven subjects performed a visuo-spatial task requiring judgement about the length of the two segments of asymmetrically bisected horizontal lines, presented for 50 ms on a computer monitor. After each visual s…
C4-dicarboxylate carriers and sensors in bacteria
2002
AbstractBacteria contain secondary carriers for the uptake, exchange or efflux of C4-dicarboxylates. In aerobic bacteria, dicarboxylate transport (Dct)A carriers catalyze uptake of C4-dicarboxylates in a H+- or Na+-C4-dicarboxylate symport. Carriers of the dicarboxylate uptake (Dcu)AB family are used for electroneutral fumarate:succinate antiport which is required in anaerobic fumarate respiration. The DcuC carriers apparently function in succinate efflux during fermentation. The tripartite ATP-independent periplasmic (TRAP) transporter carriers are secondary uptake carriers requiring a periplasmic solute binding protein. For heterologous exchange of C4-dicarboxylates with other carboxylic …