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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Utvärdering av bildkvalitet i digitala panoramaröntgenbilder, med och utan bildbehandling

Gross, Heidi January 2013 (has links)
Studien utvärderade bildkvaliteten hos digitala panoramaröntgenbilder och korrelerade denna med synbarhet av normalanatomiska strukturer i bilderna. Studien undersökte även påverkan av subjektiv bildbehandling med avsikt att förbättra synbarheten av strukturerna.500 panoramaröntgenbilder (DICOM-format) framtagna med ett digitalt bildplattesystem utvärderades kvalitativt. Bildkvaliteten och synbarheten av utvalda normalanatomiska strukturer utvärderades i samtliga bilder. Bristande bildkvalitet medförde en subjektiv bildbehandling varefter en ny utvärdering gjordes.Enbart 10% av samtliga bilder var optimala. Felen bland de resterande bilderna dominerades av att patienten inte höll tungan mot gommen och positioneringsfel. Att patienterna ej höll tungan mot gommen påverkade i hög grad synbarheten av strukturer i maxilla. 80.5% (70 bilder) av alla bilder med horisontella positioneringsfel var till vänster, varav 8.6% (6 bilder) resulterade i en icke avbildad vänster käkled. Den mest effektiva kombinationen vid bildbehandling i studien visade sig vara en ökad kontrast och en minskad ljusstyrka vilket förbättrade bilder tagna utan tungan i gommen. Bilder med positioneringsfel var dock opåverkade av bildbehandling.
12

Approaches to Pharmacological Treatment and Gene Therapy of Cystic Fibrosis

Dragomir, Anca January 2004 (has links)
<p>Cystic fibrosis (CF) is the most common lethal genetic disease in the white population. It is due to mutations in the gene coding for the cystic fibrosis transmembrane conductance regulator (CFTR), a protein that functions mainly as a cAMP-activated chloride channel. The disease impairs ion and water transport in epithelia-lined organs such as airways, digestive tract, reproductive epithelium and sweat glands. At present the only therapy is symptomatic and development of curative treatment depends on uncovering the links between the defective CFTR and the disease, as well as on improving end-point measurements. </p><p>A method has been established for studying ion transport in an easily accessible cell type (nasal epithelial cells) from normal and cystic fibrosis patients by X-ray microanalysis. This method represents a rather simple and direct way of measuring simultaneously several chemical elements of biological interest.</p><p>Studies of chloride transport by means of a fluorescent indicator (MQAE) in nasal epithelial cells from CF patients showed that the phenotype cannot exclusively be explained by the CFTR activity in patients with severe genotype. </p><p>A common Portuguese CFTR mutation (A561E) causes protein mislocalization in the endoplasmic reticulum similar to the most common CF mutation (ΔF508) and thus it should be possible to treat it with the same pharmacological strategies.</p><p>Chronic treatment of CF airway epithelial cells with nanomolar concentrations of colchicine increased the chloride efflux via chloride channels other than CFTR, strengthening the notion that colchicine could be beneficial to CF patients.</p><p>Successful <i>in vitro </i>transfection of CF airway epithelial cells with cationic vectors was possible with short incubation times. Heparin added at the end of the transfection incubation time could help to maintain the viability of the cells, without interfering with the transfection efficiency. It seems possible that heparin could be an adjuvant for non-viral mediated gene therapy.</p>
13

Approaches to Pharmacological Treatment and Gene Therapy of Cystic Fibrosis

Dragomir, Anca January 2004 (has links)
Cystic fibrosis (CF) is the most common lethal genetic disease in the white population. It is due to mutations in the gene coding for the cystic fibrosis transmembrane conductance regulator (CFTR), a protein that functions mainly as a cAMP-activated chloride channel. The disease impairs ion and water transport in epithelia-lined organs such as airways, digestive tract, reproductive epithelium and sweat glands. At present the only therapy is symptomatic and development of curative treatment depends on uncovering the links between the defective CFTR and the disease, as well as on improving end-point measurements. A method has been established for studying ion transport in an easily accessible cell type (nasal epithelial cells) from normal and cystic fibrosis patients by X-ray microanalysis. This method represents a rather simple and direct way of measuring simultaneously several chemical elements of biological interest. Studies of chloride transport by means of a fluorescent indicator (MQAE) in nasal epithelial cells from CF patients showed that the phenotype cannot exclusively be explained by the CFTR activity in patients with severe genotype. A common Portuguese CFTR mutation (A561E) causes protein mislocalization in the endoplasmic reticulum similar to the most common CF mutation (ΔF508) and thus it should be possible to treat it with the same pharmacological strategies. Chronic treatment of CF airway epithelial cells with nanomolar concentrations of colchicine increased the chloride efflux via chloride channels other than CFTR, strengthening the notion that colchicine could be beneficial to CF patients. Successful in vitro transfection of CF airway epithelial cells with cationic vectors was possible with short incubation times. Heparin added at the end of the transfection incubation time could help to maintain the viability of the cells, without interfering with the transfection efficiency. It seems possible that heparin could be an adjuvant for non-viral mediated gene therapy.
14

Träningstights- funktion, material och aktuella trender

BÖRJESSON, JOHANNA, TANEMAR, OLIVIA, AL BERAKDAR, LOUISE January 2013 (has links)
Vad kunden har för önskemål kring utformandet på ett par damträningstights med hänsyn taget till funktion, material och aktuella trender, är en frågeställning som tillämpats och undersökts i aktuell studie. Detta har vidare format den centrala forskningsfrågan samt en underfråga som är ”mäter sig marknadens utbud av damträningstights med vad kunden efterfrågar?” Syftet med denna studie är att ta fram alternativ på visuella modeller och en kravspecifikation av damträningstights. Den metod som tillgår studiens undersökning är kvalitativa intervjuer och kvantitativa intervjuer i form av en enkätundersökning. Informationsinsamlingen från respondenterna i enkätundersökningen och från en av intervjuerna med tre kvinnor som är vana träningsutövare på gym, ligger sedan till grund för kravspecifikationen som är en del av studiens syfte. Relevanta fakta om kroppens funktion vid träning, vanligt förekommande material i träningstights samt hur en designprocess går till, ingår i den teoretiska referensramen. Det är den kunskapsbas som krävs för att fullt ut förstå processen av att produktutveckla ett par träningstights. Av studiens samtliga resultat framgår bland annat ett tydligt omdöme från respondenterna i att funktion är den parametern som är viktigast på ett par damträningstights. Förklaringar om varför och i en visuellt framställd bild på hur, är vad som bland annat presenteras i resultatet. / Program: Textil produktutveckling och entreprenörskap
15

Mag-tarmkanalens anatomi och fysiologi / Anatomy and physiology of the gastrointestinal canal

Gullberg, Petra January 1999 (has links)
<p>Detta examensarbete handlar om mag-tarmkanalen och är uppdelat i två avsnitt. Den första delen handlar om mag-tarmkanalens uppbyggnad, rent anatomiskt men också hur den ser ut histologiskt. Histologin är bara ytligt behandlad då den endast är med som förklaring till vissa händelser inom fysiologin. Den andra delen, fysiologidelen handlar om de olika delarna i mag-tarmkanalen, deras funktioner och vad som reglerar dessa. I fysiologiavsnittet behandlas också nedbrytning och absorption av de olika näringsämnena.</p>
16

Hur påverkas muskelaktiviteten vid styrketräning med en tjock stång i jämförelse med en standardolympisk stång? : En EMG- studie

Sällström, Benjamin, Kareliussén, Tobias January 2010 (has links)
<p>Many everyday tasks and also many sports require good grip and forearm strength. Everything from carrying boxes and lifting a child to grab the arms and legs in various martial arts, or holding a tennis racket involving the hand and forearm muscles in various ways. It is therefore important to train these muscles to prevent injuries and congestion and to perform well in sport. A well known way to train functional strength in the hand and forearm muscles is weight training with thick handles. The purpose of this study was to investigate the differences in muscle activity in the upper arm and forearm muscles as well as the deltoids between two bars of different diameter (28mm and 57mm) in two different weight training exercises using electromyography (EMG). The weight training exercises consisted of a pulling exercise in the form of a bench row and a pressing exercise in the form of close-grip bench press. The study also examines whether there is a connection between hand strength and muscle activity, and if there is any connection between hand size and muscle activity. Results show that muscle activity between the thick bars remained unchanged in the close-grip bench press. In the bench row exercise, however, significant increases were seen in the forearm flexors and m. biceps brachii while lifting the thicker bar. The forearm extensors showed an indication of muscle activity increases while lifting the thicker bar. However, there was no connection between hand strength and muscle activity and no correlation between hand size and muscle activity. The conclusion is that the pulling exercise with the thicker bar results in higher muscle activity in comparison to a standard Olympic bar in several muscles involved, not just those directly affected by the thicker bar.</p>
17

Studies of the Elemental Composition of Airway Surface Liquid with Relevance to Cystic Fibrosis

Vanthanouvong, Viengphet January 2006 (has links)
Cystic fibrosis (CF) is an inherited disease with symptoms mainly in the respiratory tract. The airway epithelium is covered with a thin layer of fluid, the airway surface liquid (ASL). The volume and composition of ASL are important in the pathogenesis of cystic fibrosis. The composition of ASL was determined. Firstly, pig airways were analyzed by X-ray microanalysis in the frozen-hydrated state. Secondly, small Sephadex beads were left to absorb the ASL in situ and were analyzed by X-ray microanalysis. The Na and Cl concentrations in the ASL of the pig were close to those of these ions in serum. Rat tracheal ASL was hypotonic. However, rat nasal fluid was hypertonic with an extremely high concentration of K. The composition of the ASL could be influenced by pharmacological stimulation. The development of transgenic mouse models for CF may help to develop therapies for the disease. The composition of mouse ASL was investigated using different collection techniques. (1) beads mounted on filter paper, (2) beads randomly spread over the airway epithelium, and (3) beads spread over the epithelium with a syringe. No significant difference could be detected between these techniques, and mouse ASL was hypotonic. Calibration curves had to be made for each element of interest. Nasal fluid from healthy human volunteers was collected with: (1) a pipette, (2) filter paper, (3) cotton wool, or (4) Sephadex beads. Collection on filter paper and equilibration with Sephadex beads gave reliable results. The Na and Cl concentrations in nasal fluid of control subjects were about the same as in serum, but the K concentration was higher. Rhinitis or primary ciliary dyskinesia patients and CF heterozygotes had abnormally high concentrations of Na and Cl in their nasal fluid (probably due to inflammation of the nasal epithelium), and CF homozygotes had even higher concentrations of Na and Cl.
18

Innervation patterns and locally produced signal substances in the human patellar tendon : of importance when understanding the processes of tendinosis

Danielson, Patrik January 2007 (has links)
Tendinosis is a condition of chronic pain that afflicts several human tendons, not least the patellar tendon, in which case it is often clinically referred to as ‘jumper’s knee’. The exact mechanisms behind tendinosis are yet not fully understood. One draw-back in the case of patellar tendinosis has been the lack of knowledge of the innervation patterns of the human patellar tendon. It cannot be excluded that the processes of tendinosis are influenced by nerve mediators, released from nerve endings or from stimulated cells inside the tendon. Thus, the studies of the present thesis aimed to 1) map the general, sensory, cholinergic and sympathetic innervation patterns of the human patellar tendon, in both the tendon tissue proper and the loose paratendinous connective tissue surrounding the tendon, and 2) investigate the possible existence of a production of signal substances, traditionally associated with neurons, in non-neuronal tendon cells, and to see if there are signs of local cholinergic and catecholaminergic signaling pathways. Biopsies of both normal pain-free patellar tendons and patellar tendons from patients with chronic painful tendinosis were collected and investigated. The main method utilized was immunohistochemistry, using antibodies directed against synthesizing enzymes for acetylcholine and catecholamines, against muscarinic and adrenergic receptors, and against markers of general and sensory innervation. In situ hybridization (ISH) to detect mRNA for the cholinergic/catecholaminergic synthesizing enzymes was also used. It was found that the loose paratendinous connective tissue of the patellar tendon was rather richly innervated by nerve structures. These consisted of large nerve fascicles, as well as perivascular innervation in the walls of some of the larger arteries and smaller blood vessels. It was found that part of the nerve structures corresponded to sensory afferents, and that some conformed to cholinergic and, especially, sympathetic nerve fibers. The tendon tissue proper was strikingly less innervated than the paratendinous tissue. The sparse innervation that was found in the tendon tissue proper was seen in narrow zones of loose connective tissue and blood vessels, interspersed between the collagen bundles. The overall impression was that the patterns of distribution of the general, sensory, and autonomic innervations of tendinosis tendon tissue were similar to those of normal tendon tissue proper. The most pioneering findings were the immunohistochemical observations of an expression of enzymes related to production of both acetylcholine and catecholamines within the tendon cells (tenocytes) themselves, as well as of a presence of the receptors for these substances on the same cells; features that were predominantly seen in tendinosis tendons. The observations of the synthesizing enzymes for acetylcholine and catecholamines in tenocytes were confirmed by ISH findings of mRNA for these enzymes in the tenocytes. Immunoreactions for muscarinic and adrenergic receptors were also found in blood vessel walls and in some of the nerve fascicles. In summary, this thesis presents novel information on the innervation patterns of the human patellar tendon, in healthy individuals with pain-free tendons as well as in patients with chronic painful tendinosis. Furthermore, it gives the first evidence of the presence of a local, non-neuronal production in the tendon tissue of signal substances normally seen in neurons, and a basis for these substances to affect the tenocytes as these cells also display muscarinic and adrenergic receptors. Thus, the results indicate an existence of autocrine and/or paracrine cholinergic/catecholaminergic systems in the tendon tissue; systems that seem to be up-regulated in tendinosis. This is of great interest as it is known that stimulation of receptors for both catecholamines and acetylcholine can lead to cell proliferation, interfere with pain sensation, influence collagen production, and take part in vasoregulation, as well as, in the case of adrenergic receptors, promote cell degeneration and apotosis. All these processes represent biological functions/events that are reported to be affected in tendinosis. In conclusion, despite the fact that there is very limited innervation within the patellar tendon tissue proper, it is here shown that effects of signal substances traditionally associated with neurons seem to occur in the tissue, via a local production of these substances in tenocytes.
19

The neuronal and non-neuronal substance P, VIP and cholinergic systems in the colon in ulcerative colitis

Jönsson, Maria January 2009 (has links)
Ulcerative colitis (UC) is a chronic relapsing inflammatory bowel disease. Neuropeptides, especially vasoactive intestinal peptide (VIP) and substance P (SP), have long been considered to play key roles in UC. Among other effects, these neuropeptides have trophic and growth-modulating as well as wound-healing effects. Furthermore, whilst VIP has anti-inflammatory properties, SP has pro-inflammatory effects. It is generally assumed that the main source of SP and VIP in the intestine is the tissue innervation. It is not known whether or not they are produced in the epithelial layer. The details concerning the expressions of their receptors in UC are also, to a great extent, unclear. Apart from the occurrence of peptidergic systems in the intestine, there are also neuronal as well as non-neuronal cholinergic systems. The pattern concerning the latter is unknown with respect to UC. The studies in this thesis aimed to investigate the expression of SP and VIP and their major receptors (NK-1R and VPAC1) in UC colon, compared to non-UC colon. The main emphasis was devoted to the epithelium. A second aim was to examine for levels of these neuropeptides in blood plasma in UC. Another aim was to examine for the non-neuronal cholinergic system in UC, thus, to investigate whether there is acetylcholine production outside nerves in the UC colon. Methods used in the thesis were immunohistochemistry, in situ hybridization, enzyme immunosorbent assay, and in vitro receptor autoradiography. For the first time, mRNA for VIP and SP has here been found in the colonic epithelium. That was especially noted in UC mucosa showing a rather normal morphology, and in non-UC mucosa. Marked derangement of the mucosa was found to lead to a distinct decrease in VIP binding, and also a decrease in the expression level of VIP receptor VPAC1 in the epithelium. In general, there was an upregulation of the SP receptor NK-1R in the epithelium when the mucosa was deranged. The plasma levels of SP and VIP were higher for UC patients compared to healthy controls. There were marked correlations between the levels of the peptides in plasma, their levels in the mucosa and the degree of mucosal derangement/inflammation. A pronounced nonneuronal cholinergic system was found in both UC and non-UC colon. Certain changes occurred in this system in response to inflammation/derangement in UC. The present study shows unexpectedly that expressions for VIP and SP are not only related to the nerve structures and the inflammatory cells. The downregulation of VPAC1 expression, and the tendencies of upregulation of NK-1R expression levels when there is marked tissue derangement, may be a drawback for the intestinal function. The study also shows that there is a marked release of neuropeptides to the bloodstream in parallel with a marked derangement of the mucosa in UC. The cholinergic effects in the UC colon appear not only to be associated with nerverelated effects, but also effects of acetylcholine produced in local non-neuronal cells. The thesis shows that local productions for not only acetylcholine, but also SP and VIP, occur to a larger extent than previously considered.
20

Influences of paratendinous innervation and non-neuronal substance P in tendinopathy : studies on human tendon tissue and an experimental model of Achilles tendinopathy

Andersson, Gustav January 2010 (has links)
Pain of the musculoskeletal system is one of the most common reasons for people seeking medical attention, and is also one of the major factors that prevent patients from working. Chronic tendon pain, tendinopathy, affects millions of workers world-wide, and the Achilles tendon is an important structure often afflicted by this condition. The pathogenesis of tendinopathy is poorly understood, but it is thought to be of multifactoral aetiology. It is known that tendon pain is often accompanied not only by impaired function but also by structural tissue changes, like vascular proliferation, irregular collagen organisation, and hypercellularity, whereby the condition is called tendinosis. In light of the poor knowledge of tendinosis pathophysiology and recent findings of a non-neuronal signalling system in tendon tissue, the contributory role of neuropeptides such as substance P (SP) has gained increased interest. SP, known for afferent pain signalling in the nervous system, also has multiple efferent functions and has been described to be expressed by non-neuronal cells. As pain is the most prominent symptom of tendinopathy, the focus of the studies in this thesis was the innervation patterns of the tissue ventral to the Achilles tendon (i.e. the tissue targeted in many contemporary treatment methods) as well as the distribution of SP and its preferred receptor, the neurokinin-1 receptor (NK-1R), in the tendon tissue itself. It was hereby hypothesised that the source of SP affecting the Achilles tendon might be the main cells of the tendon tissue (the tenocytes) as well as paratendinous nerves, and that SP might be involved in tendinosis- development. The studies were conducted, via morphological staining methods including immunohistochemistry and in situ hybridisation, on tendon biopsies from patients suffering from Achilles tendinosis and on those from healthy volunteers. The hypothesis of the thesis was furthermore tested using an experimental animal model (rabbit) of Achilles tendinopathy, which was first validated. The model was based on a previously established overuse protocol of repetitive exercise. In the human biopsies of the tissue ventral to the Achilles tendon, there was a marked occurrence of sympathetic innervation, but also sensory, SP-containing, nerve fibres. NK-1R was expressed on blood vessels and nerve fascicles of the paratendinous tissue, but also on the tenocytes of the tendon tissue proper itself, and notably more so in patients suffering from tendinosis. Furthermore, the human tenocytes displayed not only NK-1R mRNA but also mRNA for SP. The animal model was shown to produce objectively verified tendinosis-like changes, such as hypercellularity and increased vascularity, in the rabbit Achilles tendons, after a minimum of three weeks of the exercise protocol. The contralateral leg of the animals in the model was found to be an unreliable control, as bilateral changes occured. The model furthermore demonstrated that exogenously administered SP triggers an inflammatory response in the paratendinous tissue and accelerates the intratendinous tendinosis-like changes such that they now occur after only one week of the protocol. Injections of saline as a control showed similar results as SP concerning hypercellularity, but did not lead to vascular changes or pronounced paratendinous inflammation. In summary, this thesis concludes that interactions between the peripheral sympathetic and sensory nervous systems may occur in Achilles tendinosis at the level of the ventral paratendinous tissue, a region thought to be of great importance in chronic tendon pain since many successful treatments are directed toward it. Furthermore, the distribution of NK-1R:s in the Achilles tendon described in these studies gives a basis for SP, whether produced by nerves mainly outside the tendon or by tenocytes within the tendon, to affect blood vessels, nerve structures, and/or tendon cells, especially in tendinosis patients. In light of this and of previously known SP-effects, such as stimulation of angiogenesis, pain signalling, and cell proliferation, the proposed involvement of SP in tendinosis development seems likely. Indeed, the animal model of Achilles tendon overuse confirms that SP does induce vascular proliferation and hypercellularity in tendon tissue, thus strengthening theories of SP playing a role in tendinosis pathology.

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