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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.
31

Detekce a variabilita patogenu račího moru ve vybraných populacích raků / Detection and variation of the crayfish plague pathogen in selected crayfish populations

Mojžišová, Michaela January 2019 (has links)
Crayfish plague is an emerging disease caused by the oomycete Aphanomyces astaci, a pathogen listed among the 100 World's Worst Invasive Alien Species. It was introduced into Europe in the second half of 19th century from North America and caused collapses of European native crayfish populations. Nowadays, A. astaci is widespread in Europe and has spread also to other parts of the world, threatening all susceptible crayfish of non-North American origin. The aims of this MSc thesis were 1) to provide information about crayfish plague outbreaks from recent years, and by using microsatellite and mtDNA markers reveal A. astaci genotypes involved; 2) to test healthy-looking indigenous crayfish for potential occurrence of chronic infections by A. astaci in Czechia. Six new crayfish plague outbreaks were confirmed from 2016 to 2018, involving at least five distinct pathogen strains. My results provide first evidence of the A. astaci genotype group D causing Astacus astacus and Austropotamobius torrentium mass mortalities in Czechia. MtDNA sequencing revealed two haplotypes of the D haplogroup, indicating two independent sources of infection presumably either from ornamental crayfish or spreading from neighbouring countries. The genotype group A was recorded in two A. astacus mortalities and genotype group...
32

Molekulare Evolution der metabolisch relevanten Gene MTNR1B (Melatoninrezeptor 1B) und FTO (Fat Mass and Obesity Associated)

Dietrich, Kerstin 07 February 2013 (has links) (PDF)
Die hier vorliegende Arbeit zeigt die molekulare Evolution des Melatoninrezeptor 1 B-Gens (MTNR1B) und des Fat Mass and Obesity Associated-Gens (FTO). Für beide Gene wurden in genomweiten Assoziationsstudien (GWAS) Varianten entdeckt, welche zu der Entwicklung einer Adipositas bzw. deren Folgeerkrankungen beitragen können. So wurde für Einzelbasenaustausche (SNPs) im MTNR1B (rs10830963, rs4753426) eine Verschlechterung der Nüchternglukose sowie der Insulinausschüttung gezeigt. Zudem wurde für die Allelfrequenz des rs4753426 C-Allels ein Zusammenhang mit der täglichen Sonnenscheindauer beschrieben. Im FTO wurde eine (tagging) Variante im ersten Intron identifiziert (rs9939609), welche einen erhöhten Körpermasseindex (BMI) zu vermitteln scheint und robust repliziert werden konnte. Zusätzlich konnte in den Sorben, einer in der Lausitz ansässigen Volksgruppe, eine Variante im dritten Intron (rs17818902) beschrieben werden, die ein zusätzliches, stärkeres Assoziationssignal mit einem erhöhten BMI zeigte. Dies führte zu der Fragestellung, ob MTNR1B und FTO einer Konservierung unterlegen sind. Zudem interessierten populationsspezifische Unterschiede, um die Untersuchungen in den Kontext der Hypothese des sparsamen Genotyps stellen zu können. Demnach haben Individuen mit einer genetischen Veranlagung, die ihnen eine effizientere Energiespeicherung ermöglicht, zu Zeiten von Nahrungsmangel einen Fitness-Vorteil gegenüber Nicht-Trägern. Die Konservierung zwischen den Spezies wurde mit Phylogenetic Analysis by Maximum Likelihood (PAML) betrachtet, eine Analyse die auf dem Verhältnis von nichtsynonymen zu synonymen Basenaustauschen innerhalb einer kodierenden Sequenz beruht. Die Selektion innerhalb bzw. zwischen menschlichen Populationen wurde anhand verschiedener populationsgenetischer Variablen näher beleuchtet. Sowohl für MTNR1B als auch für FTO konnte gezeigt werden, dass sie über die betrachteten Spezies im Durchschnitt stark oder sehr stark konserviert sind, was die physiologische Relevanz dieser Gene untermauert. Für MTNR1B zeigte sich zudem, dass es auf dem Ast zum Menschen nicht konserviert, sondern positiv selektioniert ist. Dies kann als Anzeichen für durch die Umwelt bedingte Einflüsse gedeutet werden. Essentielle Residuen des Rezeptors sind jedoch auch hier hochgradig konserviert. Die populationsgenetischen Variablen implizieren bei beiden Genen eine nicht-neutrale Selektion. Während sich beim MTNR1B insbesondere populationsspezifische Unterschiede anhand des Fixierungsindex Fst zeigten, konnten für FTO marginal signifikante Korrelationen zwischen der Konservierung der Haplotypen und der Stärke der Assoziation mit BMI in den Sorben gezeigt werden. Für beide Gene kann die Hypothese des sparsamen Genotyps nicht prinzipiell ausgeschlossen werden, allerdings sind weitere Untersuchungen diesbezüglich von Nöten.
33

Mutation Pattern of Lamivudine Resistance in Relation to Hepatitis B Genotypes

Damerow, Hans 25 September 2012 (has links) (PDF)
Es gibt wenige Erkenntnisse über den Zusammenhang zwischen Lamivudin induzierten Resistenzmutationen und Hepatitis B Genotypen. Die vorliegende Studie untersucht das Verhältnis zwischen diesen Mutationen und den Hepatitis B Genotypen A-D. Die Datenbank der US-amerikanischen Kongressbibliothek (Pubmed) wurde nach den Begriffen „HBV OR hepatitis B”, „YMDD”, „genotype”, und „lamivudine” durchsucht. Alle in dieser Suche gefundenen Arbeiten, die bis Juni 2009 veröffentlicht worden waren, wurden in die Studie eingeschlossen. Die Ergebnisse der Literaturanalyse wurden mit den Hepatitis B-Genomdaten zweier Referenzlabore in Tübingen und Melbourne verglichen. Insgesamt konnten 29 Arbeiten aus der Datenbankrecherche in die Literaturanalyse eingeschlossen werden. Diese Studien enthielten Daten zu insgesamt 827 Patienten, deren Hepatitis B Genotyp bekannt war und die eine Lamivudinresistenzmutation aufwiesen. In statistischen Untersuchungen konnte nachgewiesen werden, dass die rtM204V-Mutation die dominierende Mutation bei Infektionen mit Genotyp A ist. Dieses Ergebnis konnte durch die Analyse der Genomdaten der Referenzlabore bestätigt werden. Ferner konnte gezeigt werden, dass bei den Genotypen A, B, und D die rtL180M-Mutation hochsignifikant mit der rtM204V-Mutation verknüpft ist. Die Dissertationsschrift enthält neben dem Artikel „Mutation pattern of lamivudine resistance in relation to hepatitis B genotypes: hepatitis B genotypes differ in their lamivudine resistance associated mutation pattern“ (Damerow, H, Yuen L et al.; J Med Virol. 2010 Nov; 82(11):1850-8) eine Einführung in die Rationale der Studie, eine Zusammenfassung der Ergebnisse sowie ein Fazit.
34

Germplasm diversity and genetics of quality and agronomic traits in Ethiopian mustard (Brassica carinata A. Braun) /

Nigussie Alemayehu Asfaw, January 2001 (has links)
Thesis (doctoral)--Georg-August University of Göttingen, 2001. / Includes bibliographical references (p. 106-116).
35

Analýza vybraných kandidátních lokusů ovlivňujících užitkové vlastnosti a zdraví zvířat / The analysis of chosen candidate loci influencing commercial properties and animal health

ČUNÁTOVÁ, Štěpánka January 2015 (has links)
The aim of this thesis was to analyze the polymorphism in position -371bp (related to ATG start codone) of MSTN gene, SNP in position 1984bp of MYF5 gene and influence of these polymorphisms on tenderness, water holding capacity, pH and color of meat. Samples (241) of bull meat of Czech pied cattle were used for analysis. PCR-RFLP method was applied to genotype MSTN and MYF5 genes. For polymorphisms detection was used restriction endonucleases DraI (for MSTN gene) and TaqI (for MYF5 gene). From established genotypes were computed their frequencies and alleles frequencies. The frequencies of genotypes in MSTN gene were AA=0,729, AB=0,258, BB=0,013 and alleles frequencies were A=0,858, B=0,142. The frequencies of genotypes in MYF5 gene were AA=0,181, AB=0,542, BB=0,278 and alleles frequencies were A=0,452 a B=0,548. Using statistical analysis, the influence of genotypes of MYF5 gene on the water holding capacity, pH and the color of meat was determined.
36

Vliv genotypu na produkci konzumních vajec ve vybraném chovu

STRAKOVÁ, Karolína January 2017 (has links)
The aim of this thesis was to compare the indicators of egg production of hens which are bred for production of consumable eggs i.e. Hy-Line Brown and Hy-Line White in selected farms. Selected parameters of egg production were evaluated during 12-months-laying cycle. In the selected farm during the monitored period was achieved the intensity of laying 86,8 %, laying at the initial state 26.5 eggs, number of eggs included in first quality class 96.4%, mortality of egg layer 1.06%, consumption of compound feed per 1 egg 130.0 g and consumption of compound feed per 1 feeding day 110.8 g. Hy-Line Brown showed higher intensity of laying (88,0 %, respectively 85,2 %), laying at the initial state 26.7 eggs, respectively 26.1 eggs, lower consumption of compound feed 128.7 g, respectively 133.2 g. Hy-Line White showed a statistically significant higher proportion of eggs included in the first quality (97.3%, respectively 85.4%), statistically significant lower mortality (0.49% and 1.51%) and statistically significantly lower consumption mixtures per 1 egg (100.7, respectively 114.9 g).
37

Tvorba výnosu ozimé pšenice v podmínkách ekologického zemědělství / Yield formation of winter wheat in ecological agriculture

ŠEBESTOVÁ, Martina January 2008 (has links)
The diploma thesis "Yield formation of winter wheat in ecological agriculture " is focused on classification of genotypes of bread wheat on the basis of the morphological characters and yield output of bread wheat in ecological farming system. The field trials were set up by using the method of random blocks in the years 2005 and 2006 on the experimental area of the Faculty of Agriculture, University of South Bohemia in České Budějovice. 10 Austrian genotypes of bread wheat were tested: Capo, Ludwig, Clever, Eurofit, Element, Eriwan, SE 408/04, SE 320/05, SE 304/05 a SE 322/04. The results are focused on the postharvest analysis the main yield components {--} number of spike per square meter, number of grains per spike, thousand grain weight (TGW). The yield and theoretical yield is presented there too. The number of grains per spike, the level of yield and TGW were relatively high. On the other hand the number of spikes per square meter doesn´t reach to expected value in ecological farming. The results were analysed by ANOVA of main effects in programme Statistica. The tested Austrian genotypes showed the possibility of using them in the conditions of ecological farming in the Czech Republic.
38

Comparing performance of modern genotype imputation methods in different ethnicities

Roshyara, Nab Raj, Horn, Katrin, Kirsten, Holger, Ahnert, Peter, Scholz, Markus January 2016 (has links)
A variety of modern software packages are available for genotype imputation relying on advanced concepts such as pre-phasing of the target dataset or utilization of admixed reference panels. In this study, we performed a comprehensive evaluation of the accuracy of modern imputation methods on the basis of the publicly available POPRES samples. Good quality genotypes were masked and re-imputed by different imputation frameworks: namely MaCH, IMPUTE2, MaCH-Minimac, SHAPEIT-IMPUTE2 and MaCH-Admix. Results were compared to evaluate the relative merit of pre-phasing and the usage of admixed references. We showed that the pre-phasing framework SHAPEIT-IMPUTE2 can overestimate the certainty of genotype distributions resulting in the lowest percentage of correctly imputed genotypes in our case. MaCH-Minimac performed better than SHAPEIT-IMPUTE2. Pre-phasing always reduced imputation accuracy. IMPUTE2 and MaCH-Admix, both relying on admixed-reference panels, showed comparable results. MaCH showed superior results if well-matched references were available (Nei’s GST ≤ 0.010). For small to medium datasets, frameworks using genetically closest reference panel are recommended if the genetic distance between target and reference data set is small. Our results are valid for small to medium data sets. As shown on a larger data set of population based German samples, the disadvantage of pre-phasing decreases for larger sample sizes.
39

Genotypová analýza lidského cytomegaloviru u pacientů po allogenní transplantaci kmenových buněk krvetvorby. / Genotypic analysis of human cytomegalovirus in the patients after allogeneic haematopoietic stem cell transplatation.

Javornická, Tereza January 2014 (has links)
In patients after allogeneic haematopoietic stem cell transplantation (HSCT) is a human cytomegalovirus (CMV) one of the most important viral pathogens. Its detailed characteristic could provide information about the impact of each CMV genotype on overall survival of the patient, and some serious complications, such as graft versus host disease (GvHD). This thesis deals with retrospective genetic analysis of samples from 1877 patients transplanted at the Clinic of Pediatric Hematology and Oncology, University Hospital Motol and the Institute of Hematology and Blood Transfusion since 2002. DNA from biological samples (especially whole blood) was isolated kit Qiagen DNA Blood Mini or Qiagen DNA Mini and samples were prospectively detected presence of CMV DNA. Samples were subsequently stored at -20 řC. Genotyping was performed using real-time PCR technologies to the genes of 2 structural proteins glycoprotein B, glycoprotein H and using sequence specific primers and probes. In 1343 samples (71.6%) from 390 patients there was only one strain of CMV; in 256 (13.6%) samples from 113 patients have detected mixed infection caused by two or more strains of CMV. The most common genotype demonstrated in "single" infection was in pediatric and adult patients gB1/gH2 detected in 118 (28.4%) patients. Most...
40

Studium výskytu genotypů lidského parvoviru B19 u pacientů FN Motol / Human parvovirus B19 genotype study among the patients of Motol Univeristy Hospital

Dubišová, Mária January 2018 (has links)
Parvovirus B19 is a common human pathogen that typically infects erythroid progenitors and causes hematological problems such as anemia and aplastic crises. The clinical presentation depends mainly on the immunological status of the patient. PVB19 can cause serious clinical disorders in immunocompromised patients after transplantation. More than 1500 samples from 90 patients who passed the HSCT in 2015 were tested for the presence of PVB19 in this work. This work describes the incidence of the virus and two typical periods of onset of infection in patients after the transplantation. Although several sources report the negative effect of PVB19 infection on the survival of allogeneic graft patients, this work did not confirm this assertion. Also, the results of this work suggest that allogenic grafts are not the main source for transmission, but that it is likely to be reactivated after long-term persistent or latent PVB19 infections. PVB19 is divided into 3 genotypes. Genotype 1 is the most widespread, genotype 2 is very rare in Europe for the last 10 years, and genotype 3 occurs mainly in tropical localities. This work as the first describes the distribution of genotypes in the Czech Republic. More than 130 samples from 125 PVB19 positive patients, stored in the Motol University Hospital from 2004...

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