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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.
71

The subthalamic nucleus in health and disease

Zhang, Yu January 2020 (has links)
Parkinson’s disease (PD) is the second most common neurodegenerative disorder in the world. PD is caused by degeneration of the dopaminergic neurons in the substantia nigra pars compacta (SNc). Deep brain stimulation (DBS) is a surgical therapy used in PD to alleviate motor dysfunction by application of high-frequency stimulation through implanted electrodes. STN is an important target of DBS electrodes in PD treatment. However, a series of side effects have been reported upon STN-DBS treatment, and the reliability of the method could be clinically improved. To achieve this, anatomical and functional studies in mice can contribute important knowledge. There are different models to explain the internal STN organization, each of which has experimental evidence. Previous work has shown that the Vesicular glutamate transporter 2 (Vglut2) and Paired-box homeodomain transcription factor 2 (Pitx2) genes are needed for normal development and function of the STN in mice. These genes are expressed throughout the STN and their use as markers for STN neurons has enabled functional studies. To progress, more knowledge of the internal organization of the STN would be useful. Here, three antibodies representing three potential STN markers were tested using immunohistochemistry. PCR analysis was used to genotype Pitx2-Cre transgenic mice that are currently used for functional and behavioral STN studies.
72

Optimizing methods for analyzing the skin microbiota

Riskumäki, Matilda January 2019 (has links)
No description available.
73

Automated Permeability Assays for Caco-2 and MDCK Cells

Zitto, Hany January 2021 (has links)
No description available.
74

FOOD PREFERENCES ASSOCIATED WITH AGE, SEX ANDWEIGHT CATEGORY.

Örman, Ola January 2021 (has links)
A large proportion of the population is over 65 years of age and this will continue to rise inthe years to come. According to the World health organization and the US National instituteof aging, as a person ages an increasing loss of appetite leads to problems of getting thenecessary nutrition. To be able to maintain health with age, we need an improvedunderstanding of how food preferences are affected by age. The hypothesis for this project isthat food preferences are influenced by age and reflected by weight. Thus, the aim of thestudy was to map food preferences and quality of diet for people with a Swedish diet betweenthe ages of 18-65. The participants completed an electronic questionnaire with a hedonic scalefor 87 different foods and activities. The results indicate that in Sweden, age had a positiveeffect on taste preferences, towards healthier food within the age range studied. It also showedthat participants with a higher body mass index (BMI) generally had a greater preference forproducts high in sugar and fat than those with a lower BMI. This study fills an importantknowledge gap and provides insight into how the quality of individuals' diet changes withage.
75

Kan kombinationsterapi CTLA-4 hämmare ipilimumab och PD-1 hämmare nivolumab eller pembrolizumab ge en bättre behandlingseffekt mot malignt melanom?

Andersson, Elena January 2020 (has links)
Malignt melanom är den tredje vanligaste cancersjukdomen i Sverige och drabbar både kvinnor och män. Det kännetecknas av en växande mörk fläck större än 5 mm som oftast uppstår i befintliga nevi, dock kan det även börja som ny förändring i huden. Malignt melanom bör misstänkas om gamla nevi ändrar storlek, form, växer snabbt, kliar och blöder. Den vanligaste formen är ytligt spridande malignt melanom som botas med kirurgi. Om tumören inte opereras bort, kan den med tiden sträcka sig ner i huden och ge metastaser. Behandlingen av melanom som spridit sig beror på i vilket stadie (I-IV) tumören befinner sig, där stadie IV är det allvarligaste. Prognosen vid malignt melanom har länge varit dålig men nu finns det immunterapi som ger bättre totalöverlevnad (OS) och en längre progressionsfri överlevnad (PFS). CTLA-4-hämmare, ipilimumab och PD-1-hämmare, nivolumab alternativt pembrolizumab är T-cellsaktivernade antikroppar som används vid melanombehandling. Syftet med detta arbete var att undersöka vilken behandling som ger bättre klinisk nytta med avseende på bättre OS och längre PFS hos patienter med malignt melanom, om behandling med ipilimumab som monoterapi eller i kombination med nivolumab eller pembrolizumab är att föredra? Detta är en litteraturstudie där fem artiklar om effekten av ipilimumab som monoterapi samt i kombination med nivolumab eller pembrolizumab ensamt analyseras. Alla fem studier hämtades från Pubmed. Patienter som fick kombinationsbehandlig av ipilimumab + novilimumab fick en bättre OS och en längre PFS jämfört med patienter som fick ipilimumab som monoterapi. Efter en medianuppföljningstid på 3 år var median PFS 2,9 månader (95% konfidensintervall (CI), 2,8 – 3,2) för ipilimumabgruppen jämfört med 11,5 månader (95% CI, 8,7 – 19,3, p <0,001) i ipilimumab+nivolumabgruppen. Det var 34% patienter som överlevde efter tre år med ipilimumab ensamt jämfört med 58% med kombinationsbehandling. Kombinationsbehandling gav bättre effekt på OS och PFS men på bekostnad av flera toxiska, behandlingsrelaterade biverkningar. Det behövs mer forskning kring dessa läkemedel för att hitta biomarkörer och för att minska biverkningarna.
76

Förebygga okontrollerade skogsbränder genom ett skogsbruk med fokus på boreal skogsekologi

Ahl, Johanna January 2020 (has links)
No description available.
77

Understanding the Northern pike (Esox lucius) through accelerometer, is it possible?

Andersson, Oskar January 2020 (has links)
Accelerometer biologgers är ett verktyg för att identifiera beteenden hos djur. För att kunna använda accelerometern effektivt är det viktigt att träna en maskin–inlärning algoritm för att kunna identifiera olika beteenden utifrån accelerations data. Denna studie testar om accelerometer går att effektivt använda på gäddan (Esox lucious) för att kunna identifiera de olika beteendena för att senare kunna användas på en stor skalig studie. Fem gäddor användes i studien och varje gädda hade en accelerometer i sin kroppshålighet. Gäddorna var filmade i en pool och data användes för att träna en maskin-inlärnings algoritm för att identifiera åtta beteenden, simmar, simmar tillsammans med andra gäddor, hantering av byte, inaktivitet, skrämd/flyr, lyckad attack, misslyckad attack och attack mot en annan gädda. Studien visar att det går att se skillnad mellan beteendena till en viss gräns. Inaktivitet, simmar och de olika attackerna kunde skiljas åt. Det gick inte att se skillnad mellan simmar och simmar tillsammans samt se skillnad mellan de olika attackerna. Flykt kan blandas ihop med simmar och attackerna. För att se skillnad mellan lyckad och misslyckad attack kan hantering av byte användas för att identifiera lyckad attack, dock funkar bara då bytet inte sväljs helt. Programmet behöver mer träning för att inte missta flykt och de olika attackerna med hantering av byte. Studien visar att accelerometer kan användas på en större skala, huvudsakligen för att se skillnad mellan inaktivitet, attacker och simmar. / Acceleration biologgers are tools to measure activity in animals and to identify behavioural modes. To use this technology efficiently it is important to train a machine learning algorithm to identify behavioural modes from acceleration data. This study test this technology on the Northern pike (Esox luscious) to determine if it is possible to measure pike behaviour in larger field’s studies. To do this five Northern pike was caught and implanted with accelerometers. The pikes were filmed in a pool with the accelerometer in their body cavity and the data was used to train a machine learning algorithm to identify eight behaviours, swimming, swimming together with other pikes, attacking other pikes, fleeing/scared, successful attack, unsuccessful attack, prey handling and inactivity (sleeping, waiting etc.). Inactive, swimming and the three attacks can be differentiated. Swimming and swimming together could not as well for the three different attacks. To differentiate successful attack and unsuccessful attack prey handling can help to identify successful attack. This only works if the prey was not swallowed directly. The results are promising as it indicates that with practice the program can be used at a larger scale field study to identify inactivity, swimming and attacks.
78

To identify novel oncogenes for the design of novel tools for diagnosis and treatment of cancer

Mandiramoorthy, Selva Kumar January 2018 (has links)
Cancer is a disease caused by an uncontrolled cell growth that destroys the healthy tissue of the body. It is one of the deadliest diseases in the world that alters many cellular mechanisms and features. In this report, a list of 22 upregulated oncogenes is studied to identify the novel oncogene. The need to determine the novel oncogene is to develop the anti-cancer agent. To determine the novel oncogene, gene enrichment analysis (GEA) was performed. It is a method to identify classes of genes that are over-represented in the large set of genes to determine the phenotypes of the organisms. DAVID and PANTHER are the methods used to carry on this study as it has Gene Ontology (GO) embedded in it. The GEA uses fishers exact test to determine the enriched gene by the standard p-value of 0.05. To further study the oncogene Network Enrichment Analysis was performed with EVINET. We found that microtubule was significantly enriched in NEA. The genes significantly enriched for GO microtubule were studied. The significantly enriched microtubule in NEA might then be used as a target for anti-cancer agent and used to develop the drug in the future.
79

Real-time measurement of locus coeruleus (LC) activity during eating and mild stress with fiber photometry

Asker, Mohammed January 2019 (has links)
Stress has been always associated with a deviating than normal feeding behavior. Both over-eating and under-eating accompanied by altered food choice towards palatable food have been reported in response to stress. The neuronal pathways that link stress with eating are still unclear. Locus Coeruleus (LC) is the main endogenous norepinephrine (NE) secreting nucleus. It lies in the center of the stress response mediating arousal state. LC-NE nucleus with its widespread innervations throughout the brain can modulate brain mechanisms linked with motivation towards food. In this study, the aim was to study the activity of NE neurons in the LC in relation to stress and food intake. The hypothesis was that NE neurons are activated by mild stressors and that this activity drives food intake. Because the association between LC activity and food intake is observational by nature, it is not expected to demonstrate a causal link but to show findings consistent with this hypothesis. Another aim was to standardize the photometry measurements and an analysis paradigm. In response to a stressor, animals showed freezing behavior, with photometry recordings displaying a significant reduction in Ca+2 signals right after the distressing stimulus. When a stressor preceded food intake, LC-NE activity significantly decreased right after the first meal the effect that did not last to the second meal with no difference between chow and palatable food. These results highlight the involvement of LC-NE in modulating feeding behavior by integrating environmental cues and internal needs. Future investigations of distinct, projection-defined, LC-NE sub-populations may reveal more specific food and stress interactions.
80

How low levels of glucose and tryptophan may signal changes in development and symbiotic potential of ectomycorrhizal fungus Laccaria bicolor

Goetsch, Alexandra January 2020 (has links)
Symbiosis between tree species and ectomycorrhizal fungi is a fundamental relationship that promotes the overall health of boreal and temperate forests. Nutrient exchange between the two organisms is mutualistic in nature however establishment of this relationship is still not fully understood. Many molecules including phytohormones, sugars, and amino acids have been shown to be involved in this symbiotic process from establishment to prolonged interactions. Fungal auxin is known to be a key phytohormone in this interaction and it has been proposed that its production in ectomycorrhizal fungi is to aid in the fungi’s ability to establish symbiosis. Other molecules, however, have been proposed to work in conjunction with auxin to initiate these organismal interactions, questioning the role of fungal auxin as a master regulator. In this study, the effect of sugar and tryptophan feeding on growth and ectomycorrhiza formation was assessed. Free-living cultures of model ectomycorrhizal fungus Laccaria bicolor and lines altered (either overexpressing or RNAi-silenced) for expression of the auxin biosynthesis enzymes Aldehyde Dehydrogenase, Ald1 and Ald2 were utilized. A selection of these lines were grown in contact with common symbiotic tree species partner Populus. Fungal biomass, expression of auxin biosynthesis and transport-related genes, auxin production and the presence of ectomycorrhiza under different sugar and tryptophan concentrations was assessed. Eight out of 21 tested genetically modified L. bicolor lines secreted significantly different levels of indole-3-acetic acid as compared to the wild type when grown in standard glucose conditions and supplemented with tryptophan. Biomass production of wild type L. bicolor and transgenic lines was positively correlated to sugar concentrations in the medium, regardless of supplementation with tryptophan or genotype. Expression analysis for four of five auxin-related genes showed reduced expression for auxin-biosynthesis genes Ald1, Ald2 , and Ald3 and the putative auxin transport gene, ABCB5, in a selected line that was RNAi-silenced for Ald2. In addition, expression of Ald1, 2, 3 and ABCB5 in the WT fungus appeared to be up-regulated in low-sugar conditions as compared to standard sugar conditions supplemented with tryptophan. Bringing together these results allows for proposition of a first model to conclude how low glucose and tryptophan work together as signals to impact auxin pathways in the ectomycorrhizal fungus Laccaria bicolor to modulate fungal growth and affect its symbiotic potential.

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