Search for dissertations about: "protective effect"

Showing result 1 - 5 of 656 swedish dissertations containing the words protective effect.

2. 1. Gastrointestinal mucosal protective mechanisms : Mudolatory effects of Heliobacter pyroli on the gastric mucus gel barrier and mucosal blood flow in vivo

   Author : Christer Atuma; Uppsala universitet; []
   Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Physiology and anatomy; mucus gel layer; mucosal blood flow; mucus thickness; chronic infection; rat; platelet activating factor; mast cell; nitric oxide; nitric oxide synthase; ketotifen; intra-vital microscopy; microelectrode; laser-Doppler flowmetry; L-NNA; Fysiologi och anatomi; Physiology and pharmacology; Fysiologi och farmakologi; Physiology; fysiologi;

   Abstract : The gastrointestinal mucus gel layer and blood flow are two important mechanisms for protection at the pre-epithelial and sub-epithelial levels, respectively. Helicobacter pylori might circumvent these mechanisms and elicit a chronic inflammatory response with consequent ulcers in the stomach and duodenum. READ MORE

4. 2. Power Quality Disturbances and Protective Relays

   Author : Fan Wang; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; overcurrent relays; component switching; frequency deviation; power system disturbance; protection algorithms; power quality; digital protective relays; impedance relays;

   Abstract : This thesis combines knowledge from two areas: power quality and power system protection. Power quality concerns the effect of voltage disturbances on end-user equipment and of current disturbances on network components. Power system protection concerns the detection of faults in the system from measured voltages and currents. READ MORE

5. 3. Parameters affecting the functionality of additives in lubricated contacts : effect of base oil polarity

   Author : Aldara Naveira Suarez; Luleå tekniska universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Maskinelement; Machine Elements;

   Abstract : Traditionally rolling contact fatigue observed in bearing field applications was subsurface initiated. However, despite the improvement of steel properties, some factors such as downsizing in bearing design, extreme loading of the bearings as well as demanding application conditions (start up-stop cycles) have led to an increase on the cases of surface damage related to surface initiated fatigue, that comes basically from surface distress. READ MORE

6. 4. Apoptosis in the myelodysplastic syndromes : protective effect of G-CSF

   Author : Jan Schmidt-Mende; Karolinska Institutet; Karolinska Institutet; []
   Keywords : ;

   Abstract : Increased apoptosis of hematopoietic progenitor cells is a hallmark for the myelodysplastic syndromes (MDS), and one of the main reasons for the ineffective hematopoiesis and subsequent cytopenia characteristic for the disease. In particular in low risk MDS, such as refractory anemia (RA) and refractory anemia with ringed sideroblasts (RARS), severe transfusion-dependent anemia leading to constant fatigue and weakness and therefore reduced quality of life often constitutes the main clinical problem. READ MORE

7. 5. Protective Tribofilms on Combustion Engine Valves

   Author : Robin Elo; Staffan Jacobson; Mikael Åstrand; Uppsala universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Internal combustion engine; valve; sealing surface; tribofilm; oil residue; test rig; Teknisk fysik med inriktning mot tribomaterial; Engineering Science with specialization in Tribo Materials;

   Abstract : Inside the complex machinery of modern heavy-duty engines, the sealing surfaces of the valve and valve seat insert have to endure. Right next to the combustion, temperatures are high and high pressure deforms the components, causing a small relative motion in the interface. READ MORE