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Din sökning på "swedish" gav 92232 sökträffar

Microvascular inflammatory response in the skin

This thesis examines the microvascular inflammatory response in the skin. The microvascular response includes vasodilatation and plasma exudation. In the first three studies, the combined response was measured in guinea pig skin with a technique based on detection of radiolabelled protein. Transferrin was labelled in vivo by injection of 113mIn and the conversion electrons detected over the skin u

Vascular receptor changes in ischemic stroke

The present thesis aimed to examine how ischemic stroke affects the vascular endothelin and angiotensin systems in cerebral arteries. To study vascular receptor changes in ischemic stroke transient focal ischemia was induced in rats. In addition, rat cerebral arteries and arterial smooth muscle cells were cultured for further analysis of cerebrovascular receptor regulation. For functional studies

The role of young-of-the-year fish in lake ecosystems

Food chain theory is based on consumption; that is, presupposing that the only important interaction between organisms is that they actually meet in an unstructured environment and that one of them is consumed. Recently, studies, including biomanipulation projects, have indicated that trophic interactions are more complex than predicted by food chain theory. In this thesis I examine the role of yo

Integrated Chromatographic Systems for On-Line Bioprocess Monitoring Based on Microdialysis or Tangential Flow Filtration

Systems for on-line monitoring of bioprocesses were developed, consisting of a membrane-based sampling unit, a liquid chromatographic (LC) separation step, and a detector. Two sampling units, a tangential flow filtration (TFF) module and a microdialysis probe, were characterised and evaluated for use in different types of bioprocesses. When using the TFF module, an additional sample clean-up step

Histamine receptors and neuropeptides in the cranial circulation

The sensory neuropeptides substance P (SP) and calcitonin gene-related peptide (CGRP) are present in human cerebral, meningeal and temporal arteries, as are peptides associated with the sympathetic (neuropeptide Y, NPY) and parasympathetic (vasoactive intestinal peptide, VIP) nervous system. NPY is a vasoconstrictor in cerebral and meningeal arteries and potentiates noradrenaline (NA) as a vasocon

Laminins and Fibulins in Bone Marrow

Development of hematopoietic cells in bone marrow takes place in association with the hematopoietic microenvironment. Extracellular matrix (ECM) molecules and stromal cells in bone marrow provide a structural environment for hematopoietic cells, but they also directly influence proliferation, differentiation and migration of cells by signal transduction mediated by ligand binding to cell surface a

Receiver Front-Ends in CMOS with Ultra-Low Power Consumption

Historically, research on radio communication has focused on improving range and data rate. In the last decade, however, there has been an increasing demand for low power and low cost radios that can provide connectivity with small devices around us. They should be able to offer basic connectivity with a power consumption low enough to function extended periods of time on a single battery charge,

Retroviral gene transfer to repopulating hematopoietic cells

Hematopoietic stem cells (HSCs) have the capacity to maintain hematopoiesis throughout life. HSCs are ideal targets for permanent gene transfer, as the transgene will be expressed in all the progeny of the gene-modified stem cells. The aim of this thesis was to optimize conditions for retroviral gene transfer to human candidate HSCs and to study mechanisms interfering with efficient gene transfer.

Endothelium-derived Vasoactive Factors and Leukocyte-derived Inflammatory Mediators. Studies in subjects with or at risk for vascular disease

This study was undertaken to evaluate relationships between endothelial function (assessed as mediators of endothelium-derived vasoactive factors such as nitric oxide [NO], prostacyclin [PGI2] and endothelin [ET-1] ), and risk factors for atherosclerosis, as well as to study possible relationships between endothelial function and leukocyte activation (indicated by measurements of leukocyte-derived

The ubiquity and type diversity of papillomaviruses in normal skin

Papillomaviruses are a diverse, epitheliotropic group of viruses. Some genotypes are the main cause of anogenital cancer in humans; others can induce skin lesions. In order to investigate the occurrence of subclinical skin infections with human papillomavirus (HPV), a pair of degenerate primers (FAP59/64) was designed. Moist cotton-tipped swabs were used as a gentle method of sample collection. Di

Psychoacoustics and hallucinating schizophrenics. A psychobiological approach to schizophrenia

Psychoacoustic experiments have been conducted for schizophrenic patients with auditory hallucinations in their case history and for reference subjects. The aim of the thesis has been to assess differences between the two groups of subjects. The experiments consisted of tests on perceptual grouping mechanisms measuring how sound with high and low pitches is separated into perceptual streams (Study

Neuroprotective and regenerative actions of GDNF and neurturin on nigral dopamine neurons in rat models of Parkinson’s disease – Prospects for clinical use of neurotrophic factors in neurodegenerative disorders

Parkinson’s disease is characterized by progressive degeneration of the nigrostriatal dopamine system, which results in tremor, rigidity, akinesia and postural abnormalities. New therapeutic strategies are aimed at halting the neurodegenerative process or restoring the system by transplantation of fetal dopamine neurons. We have investigated the potential of the neurotrophic factors glial cell lin

Aspects of beta cell and thyroid autoimmunity in children

The two most common autoimmune endocrine diseases in children are autoimmune thyroiditis (AIT) and Type 1 (insulin-dependent) diabetes mellitus (IDDM). Autoantibodies (ab) can be found several years before clinical diagnosis in both diseases. The aims of this study were to investigate the prevalence of thyroid ab in children with IDDM and in children with allergic diseases; to study islet ab and t

Barley- and Legume Products Beneficially Affect Metabolic Responses and Appetite Regulation

The role of dietary fibre (DF) in disease prevention has been extensively investigated and prospective studies observed that increased DF intake decreased the risk of cardiovascular disease (CVD), reduced the risk of weight gain as well as the risk of type 2 diabetes (T2D). Also a diet characterized by low glycaemic index (GI) has been shown to reduce the risk of T2D and CVD. More recently, eviden

Musculoskeletal pain rehabilitation A one-year follow-up of occupational performance, psychosocial functioning and disability

Multidisciplinary pain rehabilitation programmes are found decreasing pain and improve back-to-work rates. There is, however, a lack of knowledge in several respects. The overall aim of this thesis was to study outcomes in terms of occupational performance, satisfaction with performance, psychosocial functioning, disability, and coping profiles at a one-year follow-up after a musculoskeletal pain

Hematopoiesis: Functional Insights by Cell Fate Conversion

Blood cell formation, or hematopoiesis, is maintained by rare hematopoietic stem cells (HSCs) residing in the bone marrow (BM). HSCs may self-renew (the process whereby HSCs replicate to produce new HSCs) to preserve their own numbers, as well as initiate a highly coordinated hierarchical differentiation process that results in the production of mature effector blood cells. Aging is characterized

Midkine - a host defence protein

Every day we encounter many potentially harmful microbes in our environment. The epithelial linings constitute an anatomical barrier protecting us and they also produce antimicrobial polypeptides (AMPs) that act as a chemical barrier. These AMPs are small and positively charged, killing a broad range of microbes rapidly. They can either be constitutively produced or rapidly induced when epithelial

Ecosystems in the Anthropocene: the role of cropland management for carbon and nitrogen cycle processes

Through deforestation and conversion of natural ecosystems to croplands and pastures, have humans released vast amounts of carbon (C) dioxide (CO2) into the atmosphere. Roughly one third of the cumulative anthropogenic emissions until today stem from these practices, the remainder being mostly due to fossil fuel combustion. The extra CO2 has caused an increase in global air temperature, and both t

On the Fundamentals of the Engineering Design Process

In an industrial context when the product development cycles are shortened and constraints on technical innovations are high, it is very important to provide a very efficient and effective engineering design activity. In the current engineering design literature, most methodologies are by and large based on the so-called systematic engineering design approach. This approach is characterized by an