Search for dissertations about: "outer hair cells"

Showing result 1 - 5 of 20 swedish dissertations containing the words outer hair cells.

2. 1. Hair cell and organ of corti responses to normal and intense acoustic stimulation

   Author : Anders Fridberger; Karolinska Institutet; Karolinska Institutet; []
   Keywords : Cochlea; outer hair cells; calcium; pressure changes; micromechanics; noise-induced hearing loss; fluorescent indicators; laser interferometry; temporal bone preparation; guinea pig;

   Abstract : The principal aims of the studies described in this thesis were to develop an in vitro model for studying acoustic overstimulation at the cellular level, to define the electrical and mechanical response characteristics of the perfused temporal bone preparation, and to investigate the effects of intense sound stimulation on the calcium levels of the hair cells in the intact hearing organ. In the in vitro model for acoustic overstimulation, isolated cochlear outer hair cells were subjected to a pressure jet emanating from a glass micropipette aimed at the cell body. READ MORE

4. 2. The role of Lhx2 in hair follicle morphogenesis and regeneration

   Author : Gunilla Törnqvist; Leif Carlsson; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Cell and molecular biology; Cell- och molekylärbiologi; molecular cell biology; molekylär cellbiologi;

   Abstract : Hair is important for thermoregulation, physical protection, sensory activity, seasonal camouflage and social interactions. Hair is produced in hair follicles (HFs), complex mini-organs in the skin devoted to this task. READ MORE

5. 3. Dynamics of Photoinduced Processes in Dye-Sensitized Nanocrystalline Semiconductor Films--Reactions in the Photoactive Part of the Grätzel Solar Cell

   Author : Gabor Benko; Kemisk fysik; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; supraledare; magnetisk resonans; spektroskopi; magnetiska och optiska ; egenskaper elektriska; Kondenserade materiens egenskaper:elektronstruktur; spectroscopy; relaxation; magnetic resonance; supraconductors; Kemi; Condensed matter:electronic structure; electrical; femtosecond spectroscopy; solar cells; Chemistry; excited states; photoinduced electron transfer; transition metal complexes; nanocrystalline titanium dioxide; dye sensitization; porous semiconductor film; magnetic and optical properties;

   Abstract : The key materials used to convert solar energy into electricity in the Grätzel-type solar cells are dye molecules and titanium dioxide particles attached to each other. The former are similar to those in common products like purple pigments in blueberry juice, while the latter are like sunscreen, white paint, or toothpaste. READ MORE

6. 4. Atomic force microscopic studies of inner ear structure and mechanics

   Author : Alexandra Zelenskaya; Karolinska Institutet; Karolinska Institutet; []
   Keywords : Atomic force microscopy; indentation curves; mechanical properties; outer hair cells; shell-core model; electromotility; prestin; otoconia; tympanic membrane.;

   Abstract : The transduction processes occurring in the inner ear, from sound induced vibration or head movements to nerve impulses sent to the brain, are to a large part dependent on the mechanical properties of the different components of this organ, especially the sensory hair cells. The function of the hearing organ is for example dependent on the unique mechanoelectric transduction properties of the cochlear outer hair cells (OHCs), which are able to respond to electrophysiological and mechanical stimulations by changing their shape and their mechanical properties. READ MORE

7. 5. The diagnosis and protection of the auditory peripheral system

   Author : Mao Li Duan; Karolinska Institutet; Karolinska Institutet; []
   Keywords : Cochlea; inner hair cell; outer hair cell; glutamate; post-synaptic receptor; auditory brainstem response; forward masking; noise trauma; hearing loss;

   Abstract : The main focus of this thesis is on the diagnosis and prevention of peripheral hearing loss. An auditory evoked response measure (forward masking) was developed that specifically tests the function of the inner hair cells, independently of the outer hair cells. READ MORE