Sökning: "radical oxygen species"

Visar resultat 21 - 25 av 70 avhandlingar innehållade orden radical oxygen species.

1. 21. Challenges in Enzyme Catalysis - Photosystem II and Orotidine Decarboxylase : A Density Functional Theory Treatment

   Författare :Marcus Lundberg; Margareta Blomberg; Per Siegbahn; Jeremy Harvey; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; photosystem II; oxyl radical; manganese systems; orotidine decarboxylase; reaction mechanism; density functional theory; Quantum chemistry; Kvantkemi;

   Sammanfattning : Possibly the most fascinating biochemical mechanism remaining to be solved is the formation of oxygen from water in photosystem II. This is a critical part of the photosynthetic reaction that makes solar energy accessible to living organisms. LÄS MER

3. 22. Alpha-1-microglobulin: Innate defence against pathological oxidation

   Författare :Magnus Gram; Infektionsmedicin; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; alpha-1-microglobulin; pathological oxidation; hemoglobin; heme; radiation; oxidation; ROS; hemoglobin and heme antagonist; radical scavenger;

   Sammanfattning : Oxidative stress has been implicated as an important factor in the progression of many diseases. An imbalance in the redox-system may cause oxidation of cells and molecules, which might subsequently lead to tissue damage. LÄS MER

4. 23. Activation and inhibition of diiron and iron-manganese ribonucleotide reductases

   Författare :Ana Popović-Bijelić; Astrid Gräslund; Anders Hofer; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; class Ic; C. trachomatis; cytotoxicity; KP772; lanthanum; manganese–iron cofactor; metal complex; oligopeptide inhibitor; ribonucleotide reductase; Triapine; tyrosyl radical; Biophysics; biofysik;

   Sammanfattning : Ribonucleotide reductase (RNR) catalyses the reduction of ribonucleotides to deoxyribonucleotides. In conventional class I RNRs the active site is located in the R1 subunit, and the R2 subunit contains a diiron cofactor and a stable tyrosyl radical essential for activity. LÄS MER

5. 24. Mesoporous transition metal oxides for oxygen electrocatalysis in energy conversion technologies

   Författare :Zhixing Wu; Emma Björk; Magnus Odén; Mikhail Vagin; Freddy Kleitz; Linköpings universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : Electrocatalysis, the foundation of electrical to chemical energy transformation, enables the mitigation of the electrical energy losses during reactions and the control of selectivity of the process to certain chemical products. The slow rate and the multi-step complexity of oxygen-associated reactions, namely oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), motivate the use of platinum group metals (PGM) catalysts, which significantly increase the price of the technologies due to the cost and scarcity of PGM-based materials. LÄS MER

7. 25. Oxidative stress, antioxidative defence and outcome of gestation in experimental diabetic pregnancy

   Författare :Jonas Cederberg; Uppsala universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Cell biology; Diabetes; pregnancy; rat; ROS; free oxygen radicals; TBARS; isoprostanes; protein carbonyls; embryo; vitamin C; vitamin E; Cellbiologi; Cell biology; Cellbiologi; medicinsk cellbiologi; Medical Cell Biology;

   Sammanfattning : Maternal type 1 diabetes is associated with an increased risk for foetal malformations. The mechanism by which diabetes is teratogenic is not fully known. Previous studies have demonstrated that radical oxygen species can contribute to the teratogenicity of glucose and diabetes. LÄS MER