Sökning: "contrast sensitivity"

Visar resultat 6 - 10 av 354 avhandlingar innehållade orden contrast sensitivity.

  1. 6. On contrast-enhanced magnetic resonance angiography of the aortoiliac arteries

    Författare :Johan Wikström; Uppsala universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Oncology; Magnetic resonance imaging; Magnetic resonance angiography; Contrast media; Arteriosclerosis; Iliac artery; Blood pressures; Onkologi; Oncology; Onkologi; radiologi; Radiology;

    Sammanfattning : In contrast-enhanced magnetic resonance angiography (CE-MRA),vascular signal is produced by the acquisition of a T1-weighted magnetic resonance imaging scan while the presence of a contrast agent induces a low T1 in blood. In this thesis,CE-MRA of the aortoiliac arteries was evaluated. LÄS MER

  3. 7. A Study of Some Temporal Properties of the Human Visual Evoked Potential, and Their Relation to Binocular Function

    Författare :Björn Johansson; Peter Jakobsson; Anders Sjöström; Linköpings universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; VEP Visual Evoked Potential ; contrast sensitivity; binocularity; latency; Fourier analysis; strabismus; amblyopia; Ophtalmology; Oftalmologi;

    Sammanfattning : As disturbed binocular functions in small children may lead to severe amblyopia it is of interest to detect it as early as possible. Most tests for binocular functions, however, demand active cooperation and may be unreliable in children up to 4-5 years of age. LÄS MER

  4. 8. The growth hormone receptor and growth hormone sensitivity in man

    Författare :Ruth Wickelgren; Göteborgs universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; GH sensitivity; GH receptor; quantitative RT-PCR; IGF-I; skeletal muscle; adipose tissue; tissue-specific; promoter; 5´-untranslated region; psoriasis; epidermis;

    Sammanfattning : It is well established that the response to endogenous and exogenous growth hormone (GH) varies between individuals. For example, conditions with increased catabolic rate, such as trauma, sepsis and surgery, are believed to be associated with acquired GH insensitivity. LÄS MER

  5. 9. Intraocular light scattering and glare testing

    Författare :Jörgen Thaung; Göteborgs universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; light scattering; light scattering factor; glare; veling luminance; contrast sensitivity; adaptation; psychophysics; light transmission; integrating sphere; human lens; cataract; aging.;

    Sammanfattning : Aims: To analyze the parameters that are used in psychophysical glare testing and the validity of the light scattering factor (LSF). The purpose is also to investigate the light scattering properties in excised eye lenses, and to compare these properties with light transmission for different wavelengths in aging and cataractous lenses. LÄS MER

  7. 10. Vision Beyond the Fovea: Evaluation and Stimuli Properties

    Författare :Abinaya Priya Venkataraman; Linda Lundström; Hema Radhakrishnan; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Peripheral vision; Visual optics; Optical correction; Orientation; Stimulus extent; Moving stimulus; Contrast sensitivity; Visual acuity; Central vision loss; Myopia; Biological Physics; Biologisk fysik;

    Sammanfattning : This research is about evaluating vision in the periphery. Peripheral vision is of fundamental importance in the performance of our everyday activities. The aim of this thesis is to develop methods suitable for the evaluation of peripheral vision and to assess how different visual functions vary across the visual field. LÄS MER