Sökning: "Gel"

Visar resultat 1 - 5 av 737 avhandlingar innehållade ordet Gel.

1. 1. Polymer Gels as Pharmaceutical Dosage Forms : Rheological Performance and Physicochemical Interactions at the Gel-Mucus Interface for Formulations Intended for Mucosal Drug Delivery

   Författare :Helene Hägerström; Katarina Edsman; Arne Brodin; Uppsala universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Pharmaceutics; gel; rheology; mucoadhesion; mucosal drug delivery; in situ gel; gellan gum; Carbopol; tensile strength; nasal mucosa; intranasal administration; dielectric spectroscopy; Galenisk farmaci; Pharmaceutics; Galenisk farmaci;

   Sammanfattning : Drug delivery to the nasal and ocular mucosa faces several obstacles. One of these is from the effective clearance mechanisms present in the nose and eye. Polymer gels with suitable rheological properties can facilitate the absorption of poorly absorbed drugs by increasing the contact time of the drug with the mucosa. LÄS MER

3. 2. Characterization and Clinical Application of Normoxic Polymer Gel in Radiation Therapy Dosimetry

   Författare :Anna Karlsson; Malmö Medicinsk strålningsfysik; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; 3D dose verification; uncertainties; low-density gel; fractionation dependence; characterization; normoxic gel; polymer gel dosimetry; MRI; Physics; Fysik;

   Sammanfattning : Cancer is one of the main causes of death in the world, particularly in developing countries and is considered as a major public health problem. Radiation therapy has been an important modality for treatment of cancer for many decades. LÄS MER

4. 3. Radiotherapy Gel Dosimetry: Development and Application of Normoxic Polymer Gels

   Författare :Helen Gustafsson; Malmö Medicinsk strålningsfysik; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Clinical physics; radiology; tomography; medical instrumentation; Klinisk fysiologi; tomografi; medicinsk instrumentering; Radiofarmaceutisk teknik; Radiopharmaceutical technology; proton; LET; FT Raman spectroscopy; MRI; normoxic gel; IMRT; 3D verification; polymer gel dosimetry; radiologi;

   Sammanfattning : In many radiotherapy applications, true three-dimensional dosimetry with good spatial resolution that can be achieved in a single measurement would be of great value. Polymer gel dosimetry fulfils many of the demands on such a system. In this study, methods to facilitate the implementation of gel dosimetry have been investigated. LÄS MER

5. 4. Generic Properties of Polymer Solutions

   Författare :Takashi Uematsu; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; photon correlation spectroscopy; collective diffusion; atomic force microscopy; relaxation; agarose gel electrophoresis; DNA; Zimm dynamics; pulsed-field gradient NMR; superdiffusion; polymer solution; blob model; gel;

   Sammanfattning : Polymer solutions are abundantly present in our daily life, for example in paints, jellies, contact lenses and even in the living cells. Despite their ubiquity, we still have a poor understanding of the physical properties of solutions due to the extremely large number of internal degrees of freedom. LÄS MER

7. 5. On the Structure and Dynamics of Polyelectrolyte Gel Systems and Gel-surfactant Complexes

   Författare :Per Johan Råsmark; Christer Elvingson; Johan Bergenholtz; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physical chemistry; polyelectrolyte gel; microgel; dynamic light scattering; Raman spectroscopy; periodic boundary conditions; percolation; hypersphere; Monte Carlo; Brownian dynamics; Fysikalisk kemi; Physical chemistry; Fysikalisk kemi;

   Sammanfattning : This thesis describes the results of experimental work on polyelectrolyte gels and their interaction with oppositely charged surfactants, and presents two new algorithms applicable to the simulation of colloid and polymer systems.The model systems investigated were crosslinked poly(acrylate) (PA) and poly(styrene sulphonate) (PSS), and the surfactant was dodecyl trimethylammonium bromide (DoTAB). LÄS MER