Search for dissertations about: "oscillations"

Showing result 11 - 15 of 470 swedish dissertations containing the word oscillations.

  2. 11. Studies of individual pancreatic -cells : Electrophysiological analysis of rhythmic behaviour and development of new techniques

    Author : Staffan Dryselius; Uppsala universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Cell biology; Diabetes; pancreatic beta-cells; insulin release; signal transduction; cytoplasmic calcium; oscillations; patch clamp; ATP-regulated potassium channels; voltage-dependent calcium channels; metabolism; calcium ion; strontium ion; manganese ion; wavelets; de-noising; pattern recognition; superfusion; solution changes; microscopic labelling; Cellbiologi; Cell biology; Cellbiologi; medicinsk cellbiologi; Medical Cell Biology;

    Abstract : The insulin concentration in blood varies periodically, which is believed to prevent down-regulation of the hormone receptors. Loss of the regular insulin oscillations is considered to be an early sign of developing diabetes. READ MORE

  4. 12. The interplay of ions in the stimulation of the pancreatic -cell

    Author : Michael Eberhardson; Uppsala universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Cell biology; diabetes; pancreatic β-cells; cytoplasmic calcium; oscillations; glucose; tetrodotoxin; tolbutamide; veratridine; tetraethylammonium; quinine; cesium; H2DIDS; furosemide; transients; microfluorometry; fura-2; MQAE; calcium channels; potassium channels; sodium channels; chloride channels; Cellbiologi; Cell biology; Cellbiologi; medicinsk cellbiologi; Medical Cell Biology;

    Abstract : Glucose stimulation of insulin release is mediated by depolarisation of the pancreatic β-cells with accompanying entry of Ca2+ through voltage-dependent channels. An important feature of the glucose-induced depolarisation is its rhythmicity causing oscillations of the cytoplasmic Ca2+ concentration ([Ca2+]i), which trigger pulsatile release of insulin. READ MORE

  5. 13. Pulsatile insulin release from single islets of Langerhans

    Author : Johanna Westerlund; Uppsala universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Cell biology; islets of Langerhans; insulin; ELISA; cytoplasmic calcium; oscillations; type 2 diabetes; glucose; diazoxide; potassium; tolbutamide; DNP; antimycin A; iodoacetamide; microfluorometry; fura-2; KATP channels; Cellbiologi; Cell biology; Cellbiologi; medicinsk cellbiologi; Medical Cell Biology;

    Abstract : Insulin release from single islets of Langerhans is pulsatile. The secretory activities of the islets in the pancreas are coordinated resulting in plasma insulin oscillations. Nutrients amplitude-regulate the insulin pulses without influencing their frequency. READ MORE

  6. 14. On the Frequency Domain Analysis of Nonlinear Systems

    Author : Karin Ståhl; Linköpings universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Frequency domain; Nonlinear systems; Oscillations; Volterra series;

    Abstract : In this report we study how the Volterra series description of nonlinear systems can be applied to some different problems.We study oscillations in nonlinear systems. READ MORE

  7. 15. α-Cell signalling in glucose-regulated glucagon secretion

    Author : Qian Yu; Anders Tengholm; Erik Gylfe; Sebastian Barg; David W Piston; Uppsala universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Islets; glucagon; insulin; somatostatin; ATP; cAMP; Ca2 ; GHB; oscillations; α-cell; β-cell; δ-cell; Medical Cell Biology; Medicinsk cellbiologi;

    Abstract : Glucagon is a blood glucose-elevating hormone released from α-cells in the islets of Langerhans during hypoglycaemia. Glucagon is critical for glucose homeostasis and inappropriate regulation of its secretion underlies both impaired counter-regulation of hypoglycaemia and chronic hyperglycaemia in diabetes patients. READ MORE