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Hur upplever du din stress och hälsa? : Husdjurets och partnerns positiva inverkanKarlsson, Malin January 2008 (has links)
<p>I tidigare forskning finns ett samband mellan socialt stöd och reducerad stress. Även husdjur påverkar stressnivån. Denna enkätstudie tittade på om husdjur och civilstånd påverkar hälsa och stressnivå. Av de studenter som deltog i studien hade 35% husdjur. Resultatet visade inte på någon effekt på stress av att ha husdjur. Personer med partner upplevde inte mindre stress än singlar. Huruvida deltagarna bodde med sin partner eller ej spelade ingen roll för stressnivån. Husdjursantalet påverkade inte stressupplevelsen. En interaktionseffekt påvisades: Yngre singlar och äldre personer med partner upplevde mer stress än vad yngre personer med partner och äldre singlar gjorde. Studiens resultat skiljer sig från vad tidigare forskning då inga huvudeffekter av husdjur och partner kunde påvisas.</p>
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Utveckling av modulbaserad 11C-processutrustning inom PET : Presentation av idéer och koncept / Development of module-based 11C process equipment within PET : Presentation of ideas and conceptsFredén, Emil, Johansson, Sebastian January 2010 (has links)
<p>This report describes the planning and the accomplishment of the final diploma workat the study program Mechanical Engineering, Department of Engineering Sciences, Uppsala University. Two students carried out the diploma work at GE HealthcareHusbyborg in Uppsala.</p><p>The aim of the diploma work was to develop and improve existing processequipment for 11C-radiochemistry in PET. The process equipment was to be dividedinto smaller independent modules to make it more flexible. Part of the existingprocess equipment is an oven that is supposed to perform a specific chemicalreaction. One of the main goals was to study and improve this oven.</p><p>The work could be divided into three main phases: 1.Present concepts for one module, and interface between different modules. 2. Analyze and choose components for the module mentioned above. 3. Present concepts for the oven, which is placed in the module mentioned above.</p><p>At the beginning, user requirements were listed in cooperation with the mentor. Later, components available on the market and the existing process equipment wereanalyzed. A product function analysis of the oven was made to show its function and design.</p><p>The concept phase was mainly about brainstorming to generate ideas. Later, hybridization was used as a method to combine different ideas. Then two prototypeswere built and tested. The test results showed which idea seemed to be the best.Different concepts were assessed and put into a concept selection matrix, after which the best was chosen and developed further.</p>
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Blood Flow Modeling of H<sub>2</sub><sup>15</sup>O PET Studies in Liver MetastasesJonasson, My January 2010 (has links)
<p>Positron Emission Tomography, PET, is a noninvasive medical imaging technique to get functional information of the kinetics of radioactive compound injected in the body. The data used in this thesis comes from a total of five H<sub>2</sub><sup>15</sup>O PET studies of one patient. This was done in order to study the blood flow in liver metastasis of the patient, before and after treatment.</p><p>A one compartment model was used to do the ROI based analyses. With a least square method in Matlab the unknown parameters in the model, such as the kinetic rate constants, the dispersion and the fraction of blood in the tissue, was extracted. Also a brief analysis of different parts of the metastases, edge and center, was done to see the variations within the metastases. The results show some increase of the blood flow after the treatment, and two of the three studied metastases showed a distinct difference of the activity in the center versus the edge. Given in the thesis are also some basic PET and compartmental modeling theory.</p> / <p>Positronemissionstomografi, PET, är en icke-invasiv medicinsk bildteknik för att få funktionell information om kinetiken av radioaktiva föreningar injicerade i kroppen. Det data som används i denna kandidatuppsats kommer från totalt fem H<sub>2</sub><sup>15</sup>O PET-studier av en patient. Detta gjordes för att studera blodflödet i levermetastaser hos patienten före och efter behandling.</p><p>En 1-kompartmentmodell användes för att göra ROI-baserade analyser. Med en minsta kvadrat-metod i Matlab kunde de okända parametrarna i modellen, såsom den kinetiska hastighetskonstanten, spridningen och andelen blod i vävnaden, fås ut. En kort analys gjordes också av olika delar av metastaserna, kanten och mitten, för att se variationerna inuti metastaserna. Resultaten visar en viss ökning av blodflödet efter behandlingen, och två av de tre studerade metastaser visade en tydlig skillnad av aktiviteten i mitten jämfört med kanten. I rapporten ges också grundläggande teori om bland annat PET och kompartmentmodellering.</p>
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The use of PET/CT scans in the assessment of resectability of colorectal liver metastasesPatel, Seema 06 1900 (has links)
Background: Surgical treatment of colorectal liver metastases (CLRM) depends on resectability that is currently based on the CT scan. With the PET/CT scan, a more accurate pre-operative assessment of resectability may be possible.
Methods: A Cochrane-based diagnostic test systematic review and a systematic review of cost-effectiveness studies on PET scans were conducted. Lastly, a diagnostic decision analysis model was created to assess the cost-effectiveness of the technology.
Results: PET/CT scans was equally sensitive for hepatic metastases and more sensitive for extra-hepatic metastases compared to CT scans. A cost-savings of PET scans for CRLM is identified; with decision modelling demonstrating a cost-savings with the addition of PET/CT scans to the current clinical algorithm.
Conclusion: There is cautious support for the addition of PET/CT scans to the pre-operative assessment in CRLM. Unnecessary surgery may be prevented, thus decreasing wait times. Future endeavours include finding, evaluating and validating methodology for appropriate effectiveness measures. / Health Technology Assessement
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Blood Flow Modeling of H215O PET Studies in Liver MetastasesJonasson, My January 2010 (has links)
Positron Emission Tomography, PET, is a noninvasive medical imaging technique to get functional information of the kinetics of radioactive compound injected in the body. The data used in this thesis comes from a total of five H215O PET studies of one patient. This was done in order to study the blood flow in liver metastasis of the patient, before and after treatment. A one compartment model was used to do the ROI based analyses. With a least square method in Matlab the unknown parameters in the model, such as the kinetic rate constants, the dispersion and the fraction of blood in the tissue, was extracted. Also a brief analysis of different parts of the metastases, edge and center, was done to see the variations within the metastases. The results show some increase of the blood flow after the treatment, and two of the three studied metastases showed a distinct difference of the activity in the center versus the edge. Given in the thesis are also some basic PET and compartmental modeling theory. / Positronemissionstomografi, PET, är en icke-invasiv medicinsk bildteknik för att få funktionell information om kinetiken av radioaktiva föreningar injicerade i kroppen. Det data som används i denna kandidatuppsats kommer från totalt fem H215O PET-studier av en patient. Detta gjordes för att studera blodflödet i levermetastaser hos patienten före och efter behandling. En 1-kompartmentmodell användes för att göra ROI-baserade analyser. Med en minsta kvadrat-metod i Matlab kunde de okända parametrarna i modellen, såsom den kinetiska hastighetskonstanten, spridningen och andelen blod i vävnaden, fås ut. En kort analys gjordes också av olika delar av metastaserna, kanten och mitten, för att se variationerna inuti metastaserna. Resultaten visar en viss ökning av blodflödet efter behandlingen, och två av de tre studerade metastaser visade en tydlig skillnad av aktiviteten i mitten jämfört med kanten. I rapporten ges också grundläggande teori om bland annat PET och kompartmentmodellering.
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Hur upplever du din stress och hälsa? : Husdjurets och partnerns positiva inverkanKarlsson, Malin January 2008 (has links)
I tidigare forskning finns ett samband mellan socialt stöd och reducerad stress. Även husdjur påverkar stressnivån. Denna enkätstudie tittade på om husdjur och civilstånd påverkar hälsa och stressnivå. Av de studenter som deltog i studien hade 35% husdjur. Resultatet visade inte på någon effekt på stress av att ha husdjur. Personer med partner upplevde inte mindre stress än singlar. Huruvida deltagarna bodde med sin partner eller ej spelade ingen roll för stressnivån. Husdjursantalet påverkade inte stressupplevelsen. En interaktionseffekt påvisades: Yngre singlar och äldre personer med partner upplevde mer stress än vad yngre personer med partner och äldre singlar gjorde. Studiens resultat skiljer sig från vad tidigare forskning då inga huvudeffekter av husdjur och partner kunde påvisas.
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TOF-PET Imaging within the Framework of Sparse ReconstructionLao, Dapeng 2012 May 1900 (has links)
Recently, the limited-angle TOF-PET system has become an active topic mainly due to the considerable reduction of hardware cost and potential applicability for performing needle biopsy on patients while in the scanner. However, this kind of measurement configurations oftentimes suffers from the deteriorated reconstructed images, because insufficient data are observed. The established theory of Compressed Sensing (CS) provides a potential framework for attacking this problem. CS claims that the imaged object can be faithfully recovered from highly underdetermined observations, provided that it can be sparse in some transformed domain.
In here a first attempt was made in applying the CS framework to TOF-PET imaging for two undersampling configurations. First, to deal with undersampling TOF-PET imaging, an efficient sparsity-promoted algorithm was developed for combined regularizations of p-TV and l1-norm, where it was found that (a) it is capable of providing better reconstruction than the traditional EM algorithm, and (b) the 0.5-TV regularization was significantly superior to the regularizations of 0-TV and 1-TV, which are widely investigated in the open literature. Second, a general framework was proposed for sparsity-promoted ART, where accelerated techniques of multi-step and order-set were simultaneously used. From the results, it was observed that the accelerated sparsity-promoted ART method was capable of providing better reconstruction than traditional ART. Finally, a relationship was established between the number of detectors (or the range of angle) and TOF time resolution, which provided an empirical guidance for designing novel low-cost TOF-PET systems while ensuring good reconstruction quality.
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Sällskapsdjurens betydelse i omvårdnaden av den äldre människan : En litteraturstudie / The meaning of pets in the caring of the elderly people : A literature reviewLarsson, Ann-Charlotte, Gratgård, Marie January 2008 (has links)
Bakgrund: Genom tusentals år har människor och sällskapsdjur levt sida vid sida. Tidigare studier har fokuserat på de fysiska, psykiska och sociala effekterna djur har på människor. Syfte: Syftet med denna litteratur studie är att undersöka vilken betydelse sällskapsdjur har i omvårdnaden av den äldre människan. Metod: Till denna litteraturstudie samlades data in från databaserna Cinahl och Swemed. I studien användes metodprocessens åtta steg enligt Polit och Beck (2004). Tre kategorier framkom ur analysen. Dessa tre kategorier var: sällskapsdjurs betydelse för den äldre människan, sällskapsdjur som terapi och problem som kan uppstå för den äldre människan som vill umgås med djur. Resultat: Resultaten visar att sällskapsdjur har en viktig roll för många äldre människor. För äldre människor kan djur vara den viktigaste relationen och ibland den enda nära relationen de har. Djurterapi visar sig vara ett gott komplement till andra behandlingsmetoder för den äldre människan. Konklusion: Äldre människor mår bra när de umgås med djur. Djur ger en trevlig atmosfär i sin omgivning. / Background: Through thousands of year people and domestic animal have been living side by side. Earlier studies have focused on the physiological, psychological and sociological effects pets have on humans. Aim: The aim of this literature review was to examine which meaning pets have in the caring of the elderly people. Method: For this literature review, data was collected from the databases Cinahl and Swemed. In the studie a method processing in eight steps according to Polit and Beck (2004) was used. During analyse three main categories appeared. These three categories were, pets meaning of the elderly people, pets as therapy and problems which can appear when elderly people want to socialize with pets. Result: The result showed that pets have an important role in the daily life of many elderly people. For the elderly people, pets can be the most important relation and sometimes the only close relation they have. Pet therapy indicates that it is a good complement to other treatment therapies for the elderly people. Conclusion: Elderly people feel good when they socialize with pets. Pets bring a nice atmosphere in their environment.
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Partial Volume Correction in PET/CTÅkesson, Lars January 2008 (has links)
In this thesis, a two-dimensional pixel-wise deconvolution method for partial volume correction (PVC) for combined Positron Emission Tomography and Computer Tomography (PET/CT) imaging has been developed. The method is based on Van Cittert's deconvolution algorithm and includes a noise reduction method based on adaptive smoothing and median filters. Furthermore, a technique to take into account the position dependent PET point spread function (PSF) and to reduce ringing artifacts is also described. The quantitative and qualitative performance of the proposed PVC algorithm was evaluated using phantom experiments with varying object size, background and noise level. PVC results in an increased activity recovery as well as image contrast enhancement. However, the quantitative performance of the algorithm is impaired by the presence of background activity and image noise. When applying the correction on clinical PET images, the result was an increase in standardized uptake values, up to 98% for small tumors in the lung. These results suggest that the PVC described in this work significantly improves activity recovery without producing excessive amount of ringing artifacts and noise amplification. The main limitations of the algorithm are the restriction to two dimensions and the lack of regularization constraints based on anatomical information from the co-registered CT images.
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Pre-Clinical Evaluation of Biopolymer Delivered Circulating Angiogenic Cells in Hibernating MyocardiumGiordano, Céline 20 January 2012 (has links)
Vasculogenic cell-based therapy combined with tissue engineering is a promising revascularization strategy for patients with hibernating myocardium, a common clinical condition. We used a clinically relevant swine model of hibernating myocardium to examine the benefits of biopolymer-supported delivery of circulating angiogenic cells (CACs) in this context.
Twenty-five swine underwent placement of an ameroid constrictor on the left circumflex artery (LCx). After 2 weeks, positron emission tomography measures of myocardial blood flow (MBF) and myocardial flow reserve (MFR) were reduced in the affected region (both p<0.001). Hibernation (mismatch) was specific to the LCx territory. Swine were randomized to receive intramyocardial injections of PBS control (n=10), CACs (n=8), or CACs + a collagen-based matrix (n=7). At follow-up, stress MBF and MFR were increased only in the cells+matrix group (p<0.01), and mismatch was lower in the cells+matrix treated animals (p=0.02) compared to controls. Similar results were found using microsphere-measured MBF. Wall motion abnormalities and ejection fraction improved only in the cells+matrix group.
This preclinical swine model demonstrated ischemia and hibernation, which was improved by the combined delivery of CACs and a collagen-based matrix. To our knowledge, this is the first demonstration of the mechanisms and effects of combining progenitor cells and biopolymers in the setting of myocardial hibernation, a common clinical condition in patients with advanced coronary artery disease.
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