Sökning: "contrast sensitivity"
Visar resultat 21 - 25 av 354 avhandlingar innehållade orden contrast sensitivity.
21. Accuracy and reproducibility in phase contrast magnetic resonance imaging
Sammanfattning : Magnetic resonance imaging (MRI) is an imaging modality which provides good conditions for studies of flow and motion in the cardiovascular system. When using the phase contrast imaging technique, it is possible to perform velocity measurements in moving tissues and in blood. LÄS MER
22. Mitochondrial function in human skeletal muscle: with special reference to exercise and training
Sammanfattning : The overall objective of this thesis was to study the adaptation of oxidative function in human skeletal muscle to acute exercise of different modes, intensities and durations, and to endurance training. The effects of endurance training on mitochondrial function were evaluated in cross-sectional and longitudinal studies by measurements of mitochondrial oxygen consumption in isolated mitochondria and permeabilised muscle fibres and measurements of mitochondrial ATP production rate in isolated mitochondria. LÄS MER
23. Genetic factors in primary hypertension- with emphasis on renal sodium reabsorption
Sammanfattning : Genetic factors are of importance for the development of primary hypertension (HT). Intrauterine growth retardation, salt sensitivity and insulin resistance are all characteristic features of individuals prone to develop HT. LÄS MER
24. Non-invasive diagnostic methods of intracranial arteries
Sammanfattning : Aims of this thesis were to compare the agreement of different magnetic resonance angiography(MRA) techniques and digital subtraction angiography (DSA) in follow-up of intracranial aneurysms treated with coils in order to select the best MRA method, to evaluate the impact of increased iodine concentration in contrast medium and decreased tube voltage on arterial attenuation and image quality in computed tomography angiography (CTA) of intracranial arteries, and finally to evaluate the diagnostic accuracy of CTA in non-traumatic subarachnoid haemorrhage (SAH) compared to DSA and to assess the arterial attenuation (HU) as an image quality factor in this aspect. Follow-up DSA and time-of-flight (TOF) MRA at 1. LÄS MER
25. Mangafodipir trisodium (MnDPDP)-enhanced magnetic resonance imaging of the liver and pancreas
Sammanfattning : Contrast-enhanced magnetic resonance imaging (MRI) of the liver and pancreas is frequently performed to improve the sensitivity and specificity of lesion detection in these organs. The concept of using tissue-specific contrast media is to selectively enhance the normal parenchyma, but not lesions, so that the contrast between tumorous and normal tissue is increased, and lesion detectability improved. LÄS MER