• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 369
  • 168
  • Tagged with
  • 537
  • 535
  • 535
  • 520
  • 518
  • 516
  • 516
  • 43
  • 27
  • 26
  • 26
  • 24
  • 17
  • 17
  • 17
  • 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.
131

Automated Artificial Intelligence programme for quantification of proliferation marker Ki-67 on neuroendocrine tumors: A comparative study

De Silva, Melisa January 2024 (has links)
No description available.
132

Absolute quantification applications in myelodysplastic syndrome (MDS) : Metrics for an optimized ddPCR setup for testing assays of measurable residual disease mutations

Chihai, Luminita January 2024 (has links)
Cancer relapse in myelodysplastic syndrome (MDS) patients receiving bone marrow transplantation can be predicted with measurable residual disease (MRD), by droplet digital polymerase chain reaction (ddPCR). ddPCR quantifies genomic DNA molecules in an absolute manner using end-point amplification. This work aims to demonstrate that ddPCR assay evaluation can be conducted with fewer healthy donor controls compared to methods for relative quantification. The hypothesis is further studied by applying the total error computed in the ddPCR system as a threshold for background noise in personalized assays. Ten assays for detecting MRD markers were evaluated in an optimized PCR-plate setup for accuracy and reproducibility of background in negative controls. Additionally, data analysis of negative controls collected from patient tests complied to the empirical limit of blank based on false - positive counts, in each assay. The findings indicate that the optimized setup accurately determines background noise, and empirical cutoffs for individualized assays are reliable for performance evaluations. This study supports ddPCR integration into clinical settings for personalized mutation analyses in MDS, providing an optimized setup and alternative metrics of evaluating assay performance in respect to the absolute quantification methodology.
133

Neurofeedback training for children with ADHD : Evaluating the effect of personalized and standardized neurofeedback protocols on theta rhythms, beta rhythms and the iAPF

Strothmann, Senta January 2024 (has links)
Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder in children, characterized by symptoms such as hyperactivity, inattention and impulsivity, which often impairs the quality of life and successful performance. The disorder is associated with neurological, genetic and environmental factors affecting brain structure and cognitive function. Treatments include first-line pharmacological treatment, psychological therapy and neurofeedback training. Neurofeedback training with electroencephalography aims to regulate brain activity by targeting the dysregulated theta and beta rhythms, and the theta/beta ratio through personalized or standardized neurofeedback protocols to reduce ADHD symptoms and to improve cognitive function. This study aims to compare differences in the change of theta, beta and the individual alpha peak frequency (iAPF) based on personalized and standardized neurofeedback protocols targeting theta, beta and the theta/beta ratio. Nine children (age 7 to 13) were randomly assigned 16 sessions of personalized or standardized neurofeedback training over a span of two weeks; the neurofeedback protocol was personalized with the help of the iAPF. The theta and beta rhythms and the iAPF were measured by a quantitative electroencephalography and compared before and after the intervention by non-parametric Mann-Whitney-U, Wilcoxon Signed-Rank and Kruskal Wallis tests. These tests showed no significant difference between theta, beta and iAPF before and after the neurofeedback training within and across the personalized and standardized test groups. Previous studies showed an improvement of brain activity and cognitive function through neurofeedback training, but the small sample size and participant artifacts limited this study; concluding that valuable insights into neurofeedback training were gained.
134

Polycystic ovary syndrome : A PCOS model on Drosophila melanogaster induced by Dihydrotestosterone (DHT)

Fallberg, Lilian January 2024 (has links)
Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders affecting women of reproductive age. The major features of PCOS include polycystic cysts, excess androgens, and polycystic ovaries. Dihydrotestosterone (DHT) is an androgen, and when in excess causes associated with PCOS used to induce PCOS in animal models. In excess, DHT is associated with PCOS features. This study aimed to induce PCOS-like symptoms in Drosophila Melanogaster by supplementing DHT in the diet. The reproductive and metabolic features of PCOS were investigated. Fecundity rates, triglyceride levels, and gene expression levels of Toll and Med genes were assessed. The mean levels of triglycerides (P=0.023) had significantly increased in the high-dose DHT group (F2 generation). The mean expression levels (P=0.02) of the Toll gene were significantly increased in the low-dose DHT group. The treatment of DHT, however, did not affect the fecundity rates of the Drosophila. These findings suggest that DHT induces PCOS-associated metabolic features of lipid alterations and chronic low-grade inflammation. Assessment of the impact on fertility did not give conclusive results thus additional methodologies could be considered in studying the reproductive function. In conclusion, the results obtained in this study highlight the potential of using Drosophila as a model in PCOS research. / <p>Det finns övrigt digitalt material (t.ex. film-, bild- eller ljudfiler) eller modeller/artefakter tillhörande examensarbetet som ska skickas till arkivet.</p><p>There are other digital material (eg film, image or audio files) or models/artifacts that belongs to the thesis and need to be archived.</p>
135

Polycystic ovarian syndrome : Developing a testosterone-induced PCOS model in Drosophila melanogaster

Kandavalli, Shama January 2024 (has links)
Polycystic ovary syndrome is a common endocrine disorder that hinders women’s metabolism and reproductive health characterized by elevated androgen levels, polycystic ovaries, infertility, hirsutism, inflammation, obesity and insulin resistance. Research suggests mitochondrial dysfunction as an underlying cause of PCOS. This study aimed to develop a PCOS model of Drosophila melanogaster by induction of androgens (testosterone). The eggs of the wild-type stock flies were exposed to ethanol (control) and varying doses of testosterone (1-10mg/kg) and examined throughout development. Androgen and ethanol exposure caused alterations in the external morphology and ovarian appearance suggesting a link to PCOS-related symptoms. Fertility measured by fecundity rates decreased by 32.6% in androgen treated flies, though statistical tests revealed no significant differences between groups. Androgen exposure altered the mitochondrial gene expression but with no statistical difference between conditions in all genes (p values: MTCO1 = 0.368; SOD1 = 0.276; ATPsynthase = 0.102). MTCO1 showed approximately a 99% difference in low and high testosterone groups from control. SOD1 increased by 7645.72% and 98.8%, and ATPsynthase by 319.9% and 703.4%in low and high testosterone conditions, respectively. Triglyceride levels were elevated in androgen groups across F1 and F2 generations, indicating potential metabolic disruptions. Significant differences revealed between control and high testosterone (F1, p = 0.04; F2, p = 0.006) but not in low testosterone (F1, p = 0.402; F2, p = 0.328). Lack of significant findings renders the results unreliable. Future research with broader gene panels and improved methologies are required to validate the model's applicability for PCOS research. / <p>Det finns övrigt digitalt material (t.ex. film-, bild- eller ljudfiler) eller modeller/artefakter tillhörande examensarbetet som ska skickas till arkivet.</p><p>There are other digital material (eg film, image or audio files) or models/artifacts that belongs to the thesis and need to be archived.</p>
136

Optimization of PCR diagnostics for equine coronavirus

Isaksson, Kamilla January 2024 (has links)
Equine Coronavirus (ECoV) is a virus that affects horses. Symptoms of ECoV are often gastrointestinal, including fever, lethargy, anorexia, and changes in fecal consistency. While the disease is usually mild, it can lead to more severe symptoms where death has occurred. Diagnosis of ECoV is typically confirmed through Polymerase Chain Reaction (PCR) testing of fecal samples. Initial studies have shown that fecal samples from horses can inhibit PCR analysis for ECoV, other PCR systems and buffers may have a better effect on inhibition in fecal samples then the current method used at Swedish Veterinary Agency (SVA) today, leading to false negative results. To avoid false negative results due to inhibition, the option of using an internal control exists. If the internal control yields a negative result, it suggests that the PCR reaction did not function as intended and a negative result for ECoV would therefore not be reliable. The purpose of this study was to gather more information about the current method's performance and possibly optimize its sensitivity. Seven different buffers were tested to see which works best for horse feces and the current method was compared with other PCR methods in order to choose the method with the highest sensitivity. The results indicated a statistically significant difference between PB and PVP buffers. Additionally the comparison between the PCR systems in the study showed a significant difference, indicating that the new system for ECoV detection has the potential to improve upon the current routine method.
137

Jämförelse av avstånd mellan bildskärm och patient genom analys av latens vid Visual Evoked Potentials

Nordin, Henni January 2021 (has links)
No description available.
138

Sepsis diagnosis and miRNA as a potential biomakers

Waheed, Atif January 2024 (has links)
Sepsis, a life-threatening condition triggered by infection, has a long history evolving from ancient references to modern understanding. Despite advancements, its symptoms often resemble those of other illnesses until late stages, delaying recognition. The blood culture method, currently used for diagnosing sepsis, is not entirely reliable and often time-consuming, posing challenges for timely intervention in many cases. Recently, miRNAs have emerged as promising biomarkers for a variety of infectious diseases, prompting the suggestion of a new multi-marker panel for sepsis diagnosis. However, the lack of optimized methods for miRNA extraction and quantification necessitates investigation before constructing such a panel. This project aimed to examine and compare manual and robotic methods to determine which yielded superior quality, quantity, time management, and results when employing two-tailed RT-qPCR. Following experimentation, it was observed that both methods provided satisfactory purity and concentration, yet the processing time was notably shorter with the robotic method. The twotailed RT-qPCR method successfully detected DNA with copy numbers as low as 10^5 when spiked-in, although the candidate miRSeps-6 was not detectable in healthy donor plasma. Despite the unsuccessful detection of the candidate miRNA, positive controls demonstrated that processes such as manual and robotic extractions, along with two-tailed RT-qPCR, could be applied to other candidates to identify suitable matches for the kit.
139

A PCOS-like Drosophila melanogaster model

Khani, Negin January 2024 (has links)
Polycystic ovary syndrome (PCOS) stands out as one of the most widespread endocrine disorders affecting women, often presenting as the primary reason for infertility due to anovulation. Individuals with PCOS typically exhibit clinical and biochemical markers aligning with ultrasound findings, predisposing them to challenges such as hyperandrogenism, impaired fertility, obesity, irregular periods, excess body hair, insulin resistance, and recurrent miscarriages. The diagnosis relies on the 2003/2004 Rotterdam criteria, which identify polycystic ovary syndrome (PCOS) through the presence of two out of three key features: anovulation, clinical or biochemical signs of hyperandrogenism, and polycystic ovarian morphology. The potential underlying causes of PCOS may include genetic factors, environmental influences, or maternal imprinting. The study investigated the effect of different concentrations of dihydrotestosterone (DHT) on the oogenesis of Drosophila melanogaster. Drosophila melanogaster, widely utilized in disease research, offers valuable insights into this syndrome. With a life cycle spanning approximately 12 days, these flies undergo metamorphosis and produce the steroid hormone ecdysone, which is analogous to human testosterone. The main aim of the study is to develop a model for studying polycystic ovarian syndrome (PCOS) through the Drosophila melanogaster as an animal model. The data was collected by measuring the fecundity, Triglyceride concentration, and RT-qPCR. The results revealed no significant difference between the different concentrations of DHT and the control group. The results from fecundity, triglyceride assay, and RT-qPCR were notable but not significantly different. These findings suggest that additional experiments are necessary to confirm Drosophila melanogaster as a good model for PCOS. / <p>Det finns övrigt digitalt material (t.ex. film-, bild- eller ljudfiler) eller modeller/artefakter tillhörande examensarbetet som ska skickas till arkivet.</p><p>There are other digital material (eg film, image or audio files) or models/artifacts that belongs to the thesis and need to be archived.</p>
140

Method Verification of Capillary Hemoglobin A1c on Cobas Pro

Näslund, Mikaela January 2024 (has links)
Diabetes, a prevalent global group of metabolic diseases, is characterized by hyperglycemia, which can lead to potential complications with prolonged exposure. Treatment goals involve lowering blood sugar levels and preventing future complications, with glycated hemoglobin, HbA1c serving as a marker for treatment control. HbA1c, forms when glucose binds to hemoglobin, aids in treatment monitoring. This study aimed to validate capillary HbA1c analysis on the Cobas Pro analyzer to comply with new in vitro diagnostic (IVD) regulations and streamline processes. Unlike the high-performance liquid chromatography method, (HPLC) to be replaced, all reagents used in the Cobas Pro are IVD-marked. Transitioning to capillary HbA1c analysis involves a change in measurement principle. The current method utilizes ion exchange chromatography with photometric detection, while the Cobas Pro employs turbidimetric inhibition immunoassay. The correlation coefficient for 31 capillary blood samples between the methods was 0.97, with most data points falling within the confidence interval. Despite obtaining a statistically significant difference from the paired ttest, the difference between the measurement values did not exceed 3 mmol/mol, which is the proposed clinical threshold. Comparison of capillary and venous blood analyzed with Cobas Pro yielded a linear correlation of 0.99, with no significant difference found by the paired ttest. A coefficient of variation (CV) under 4% was achieved for controls on the Cobas Pro. The primary advantage of transitioning the method was that it complied with IVDR regulations and enhances patient safety. Based on these results, the method is deemed safe for implementation.

Page generated in 0.0763 seconds