Sökning: "bioavailability"

Visar resultat 16 - 20 av 239 avhandlingar innehållade ordet bioavailability.

1. 16. In Vitro Availability of Iron in High-Tannin Sorghum. Effect of Enzymatic Oxidation of Phenolic Compounds

   Författare :Erika Matuschek; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; bioavailability; catechol groups; polyphenols; polyphenol oxidase; iron; in vitro availability; tyrosinase; fruit extracts; sorghum; oxidation; tannins; galloyl groups;

   Sammanfattning : Iron deficiency anemia is the most common nutritional disorder in the world. In low income countries, it is to a large extent caused by low bioavailability of iron in the vegetable diet. Vegetable diets contain large amounts of compounds that inhibit iron absorption, e.g. LÄS MER

3. 17. Intestinal barriers to oral drug absorption: Cytochrome P450 3A and ABC-transport proteins

   Författare :Helena Engman; Per Artursson; Hans Lenernäs; Heyo K Kroemer; Uppsala universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Pharmaceutics; oral drug delivery; bioavailability; human jejunum; Caco-2; ABC-transporter; P-glycoprotein; CYP3A; Galenisk farmaci; Pharmaceutics; Galenisk farmaci;

   Sammanfattning : The subject of this thesis was to study two intestinal barriers to oral drug bioavailability, drug efflux proteins of the ABC-transporter family, and in particular ABCB1/P-glycoprotein (Pgp), and the drug metabolizing enzyme cytochrome P450 (CYP) 3A4. At the onset of this thesis, similarities between CYP3A4 and Pgp in terms of their tissue distribution and gene regulation, along with overlapping substrate specificities, had generated the hypothesis that CYP3A4 and Pgp may have a complementary function and thus form a coordinated intestinal barrier to drug absorption and gut wall metabolism. LÄS MER

4. 18. Studies on a Novel Powder Formulation for Nasal Drug Delivery

   Författare :Nelly Fransén; Erik Björk; Katarina Edsman; Lars Hovgaard; Uppsala universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; nasal drug delivery; nasal powder spray; interactive mixture; mucoadhesion; sodium starch glycolate; superdisintegrant; bioavailability; clinical trial; Pharmaceutics; Galenisk farmaci;

   Sammanfattning : Nasal administration has potential for the treatment of indications requiring a fast onset of effect or for drugs with low oral bioavailability. Liquid nasal sprays are relatively common, but can be associated with suboptimal absorption from the nasal cavity; this thesis shows that nasal absorption can be significantly enhanced with a dry powder formulation. LÄS MER

5. 19. Effects of solar radiation on the abiotic and bacterially mediated carbon flux in aquatic ecosystems

   Författare :Alexandre Magno Anesio; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; bacteria; dissolved inorganic carbon DIC ; bioavailability; aquatic macrophytes; photooxidation; detritus decomposition; Ultraviolet radiation; dissolved organic carbon DOC ; fungi; Hydrobiology; marine biology; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi;

   Sammanfattning : In this Thesis, I studied some of the current aspects of organic matter photochemistry. I analyzed abiotic phototransformations of several types of dissolved (DOM) and particulate organic matter (POM). I also evaluated the effects of phototransformation of several types of DOM on bacteria. LÄS MER

7. 20. The accessibility and chemical activity of polycyclic aromatic hydrocarbons in soil

   Författare :Fredrik Reichenberg; Centrum för analys och syntes; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Analytisk kemi; Analytical chemistry; Remediation; Bioavailability; Soil and sediment pollution; Environmental chemistry; Miljökemi;

   Sammanfattning : This thesis proposes the use of two concepts: accessibility and chemical activity. Accessibility describes the mass quantity of PAHs that is or can become available within a given time span and under given conditions. LÄS MER