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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

Detekce apikulátních a ušlechtilých kvasinek v kvasícím moštu pomocí PCR

Kosek, Filip January 2016 (has links)
In this diploma thesis we investigate how wine characteristics is influenced by the apiculate wine yeast Metschnikowia pulcherrima. For this purpose, two wines of a grape variety Welschriesling were manufactured using an identical technological approach with the only distinction: two separated musts were supplied with broth containing different yeasts. The literary part of the thesis discusses yeasts used in winery in general. We describe both apiculate yeasts and Saccharomyces. In this part, we also further discuss the polymer chain reaction and similar methods. The experimental part deals with possibilities of Metschnikowia pulcherrima DNA isolation from fermenting must and the subsequent quantification of yeasts with help of the real-time PCR method. After evaluation and comparison of the wines, where both general and expert public participated, it was concluded that the yeasts substantially influence the wine cha-racteristics.
12

Emprego da reação em cadeia pela polimerase em tempo real para o controle de eficiência de bacterinas anti-leptospirose / Employment of real time polymerase chain reaction to control the efficiency of leptospirosis bacterins

Dib, Cristina Corsi 31 August 2011 (has links)
A estirpe Fromm de Leptospira interrogans sorovar Kennewicki foi utilizada para produção de uma bacterina experimental anti-leptospirose. A extração do RNA total utilizado para transcrição reversa e quantificação dos antígenos LigA e LipL32 por PCR em Tempo Real, foi efetuada a partir de alíquotas colhidas das diluições da bacterina antes da sua inativação, as quais foram armazenadas à temperatura de -80ºC. O volume restante da bacterina foi inativado em banho-maria à 56ºC e mantido à temperatura de -20ºC para avaliação da sua potência em hamsters bem como da detecção e quantificação dos antígenos LigA e LipL32 em ensaios de ELISA Indireto e ELISA Sanduíche Indireto. Os resultados do ensaio de potência em hamsters demonstraram que a bacterina foi aprovada de acordo com as exigências dos padrões internacionais de qualidade até a diluição 1/6400, protegendo os hamters contra a infecção letal frente ao desafio com a diluição 10-6 (100 doses infectantes 50%/ 0,2mL). Os resultados das reações de Real Time PCR detectaram 3,2 x 103 e 2,3 x 101 cópias do mRNA que codifica a proteína LigA, na bacterina pura e diluída a 1:200, respectivamente. Apenas oito cópias do mRNA que codifica a proteína LipL32 foram detectadas na amostra de bacterina pura. Os ensaios com ELISA Indireto não detectaram a proteína LigA na amostra de bacterina inativada, mas demonstraram a detecção da proteína LipL32 até a diluição 1/1600 da bacterina. Os ensaios de ELISA Sanduíche Indireto apresentaram reações cruzadas nas placas controle, e, portanto seus resultados não puderam ser considerados nas análises. Os resultados da real time PCR não puderam ser correlacionados com o teste de potência em hamsters, mas os ensaios de ELISA Indireto para a proteína LipL32 demonstraram resultados condizentes com os apresentados pelo teste de potência em hamsters oferecendo uma possível alternativa in vitro para avaliação de potência de bacterinas anti-leptospirose. / Leptospira interrogans serovar Kennewicki strain Fromm was used for the production of a experimental leptospirosis bacterin. The extraction of total RNA used for reverse transcription and quantification of the antigens LigA and LipL32 for Real Time PCR was performed from the aliquots harvested of bacterin dilutions before inactivation that were separated and maintained at -80ºC. The remaining volume of bacterin was inativated at 56ºC and maintained at -20ºC for the evaluation bacterin potency in hamsters and detection and quantification of LigA and LipL32 antigens by Indirect ELISA assay and Indirect Sandwich ELISA. The results of potency assay in hamsters demonstrated that the bacterin was approved by the international patterns of quality until dilution 1/6400, protecting the hamters against lethal infection challenge by the dilution 10-6 (100 infectious doses 50%/0,2 mL). The results of Real Time PCR detected 3,2 x 103 e 2,3 x 101 copies of mRNA that encodes the LigA protein, in samples of pure bacterin and diluted 1:200, respectively. Few eight copies of mRNA that encodes LipL32 protein were detected in pure bacterin samples. Indirect ELISA assays not detected LigA protein in inactivated bacterin samples, but demonstrated LipL32 protein detection until dilution 1:1600 of bacterin. Indirect Sandwich ELISA presented cross-reaction in control plates, so the results cannot be considerated in the analysis. The results of real time PCR cannot be correlated with the potency assay in hamsters but Indirect ELISA assay for protein LipL32 demonstrated that the results were suitable with the results presented by the potency assay in hamsters offering a possible in vitro alternative for the evaluation of leptospirosis bacterins potency.
13

Emprego da reação em cadeia pela polimerase em tempo real para o controle de eficiência de bacterinas anti-leptospirose / Employment of real time polymerase chain reaction to control the efficiency of leptospirosis bacterins

Cristina Corsi Dib 31 August 2011 (has links)
A estirpe Fromm de Leptospira interrogans sorovar Kennewicki foi utilizada para produção de uma bacterina experimental anti-leptospirose. A extração do RNA total utilizado para transcrição reversa e quantificação dos antígenos LigA e LipL32 por PCR em Tempo Real, foi efetuada a partir de alíquotas colhidas das diluições da bacterina antes da sua inativação, as quais foram armazenadas à temperatura de -80ºC. O volume restante da bacterina foi inativado em banho-maria à 56ºC e mantido à temperatura de -20ºC para avaliação da sua potência em hamsters bem como da detecção e quantificação dos antígenos LigA e LipL32 em ensaios de ELISA Indireto e ELISA Sanduíche Indireto. Os resultados do ensaio de potência em hamsters demonstraram que a bacterina foi aprovada de acordo com as exigências dos padrões internacionais de qualidade até a diluição 1/6400, protegendo os hamters contra a infecção letal frente ao desafio com a diluição 10-6 (100 doses infectantes 50%/ 0,2mL). Os resultados das reações de Real Time PCR detectaram 3,2 x 103 e 2,3 x 101 cópias do mRNA que codifica a proteína LigA, na bacterina pura e diluída a 1:200, respectivamente. Apenas oito cópias do mRNA que codifica a proteína LipL32 foram detectadas na amostra de bacterina pura. Os ensaios com ELISA Indireto não detectaram a proteína LigA na amostra de bacterina inativada, mas demonstraram a detecção da proteína LipL32 até a diluição 1/1600 da bacterina. Os ensaios de ELISA Sanduíche Indireto apresentaram reações cruzadas nas placas controle, e, portanto seus resultados não puderam ser considerados nas análises. Os resultados da real time PCR não puderam ser correlacionados com o teste de potência em hamsters, mas os ensaios de ELISA Indireto para a proteína LipL32 demonstraram resultados condizentes com os apresentados pelo teste de potência em hamsters oferecendo uma possível alternativa in vitro para avaliação de potência de bacterinas anti-leptospirose. / Leptospira interrogans serovar Kennewicki strain Fromm was used for the production of a experimental leptospirosis bacterin. The extraction of total RNA used for reverse transcription and quantification of the antigens LigA and LipL32 for Real Time PCR was performed from the aliquots harvested of bacterin dilutions before inactivation that were separated and maintained at -80ºC. The remaining volume of bacterin was inativated at 56ºC and maintained at -20ºC for the evaluation bacterin potency in hamsters and detection and quantification of LigA and LipL32 antigens by Indirect ELISA assay and Indirect Sandwich ELISA. The results of potency assay in hamsters demonstrated that the bacterin was approved by the international patterns of quality until dilution 1/6400, protecting the hamters against lethal infection challenge by the dilution 10-6 (100 infectious doses 50%/0,2 mL). The results of Real Time PCR detected 3,2 x 103 e 2,3 x 101 copies of mRNA that encodes the LigA protein, in samples of pure bacterin and diluted 1:200, respectively. Few eight copies of mRNA that encodes LipL32 protein were detected in pure bacterin samples. Indirect ELISA assays not detected LigA protein in inactivated bacterin samples, but demonstrated LipL32 protein detection until dilution 1:1600 of bacterin. Indirect Sandwich ELISA presented cross-reaction in control plates, so the results cannot be considerated in the analysis. The results of real time PCR cannot be correlated with the potency assay in hamsters but Indirect ELISA assay for protein LipL32 demonstrated that the results were suitable with the results presented by the potency assay in hamsters offering a possible in vitro alternative for the evaluation of leptospirosis bacterins potency.
14

Diagnosis and vaccination for Bovine Genital Campylobacteriosis in beef heifers

2015 October 1900 (has links)
Bovine Genital Campylobacteriosis is characterized by early pregnancy loss and temporary infertility in cattle. The purpose of this project was to compare diagnostic approaches to detect Campylobacter fetus subsp. venerealis and evaluate the efficacy of vaccination for Bovine Genital Campylobacteriosis. This thesis describes the results of two studies that compared different sample preparation methods for bovine vaginal mucus for real-time PCR and assessed a commercial vaccine in preventing infection and reproductive loss. The first study compared real-time PCR utilizing different bovine vaginal mucus sample preparation techniques to direct culture. The magnetic bead based protocol demonstrated higher sensitivity (48.4%, P=0.02) and lower specificity (78.9%, P=0.01) than the heat lysis protocol which involved an additional dilution step (Sens=29.4%, Spec=88.2%), but did not differ from the heat lysis protocol without sample dilution (Sens=35.0%, P=0.16; Spec=81.1%, P=0.62). The sample preparation method, designed for bovine preputial samples (Chaban et al. 2012. Can J of Vet Res; 76: 166), did not work well for vaginal mucus. All modifications of that method and magnetic bead based extraction technique had low sensitivity compared to culture probably due to the biophysical properties of vaginal mucus, which could cause loss of targeted DNA during processing, or repeated sample freezing and thawing. Release of DNA directly from vaginal mucus by a modified heat lysis protocol with consequent real-time PCR could be a promising rapid screening approach after validating on fresh samples. The second study compared the risk of infection and reproductive failure in heifers, vaccinated with a commercial multivalent vaccine containing C. fetus antigen, to heifers vaccinated with a comparable product without C. fetus, that were exposed to infected bulls. There was no significant difference between groups either in risk of Campylobacter fetus subsp. venerealis isolation (P>0.17) or in the proportion of heifers that cultured positive at least once (P=0.42), as well as in the median number times of cultured positive samples (P=0.24) and the time to first cultured positive (P=0.67). There was no difference by treatment in the weekly proportions of heifers diagnosed pregnant by either ultrasound (P>0.31) or serum concentration of pragnancy specific protein B (P>0.31) during the study, as well as in the time to first pregnancy for heifers ever diagnosed as pregnant (P=0.30) and those that remained pregnant at the end of the study (P=0.70). Similarly, the difference was not detected by treatment in the proportion of animals, ever detected pregnant during the study (P=0.57) and in pregnancy loss rates (P=0.28). However, heifers that aborted were 4 times more likely to be cultured positive than those that did not abort (P=0.01). Heifers that were not pregnant at the end of the study cultured positive 1.5 times more often than pregnant animals in treatment group (P=0.04), while in control group such difference was 4 times (P=0.01). Heifers that were not pregnant at the end of the study did not differ by treatment in the number of times cultured positive (P=0.14). In this study, the mean concentrations of ELISA antibodies to C. fetus after vaccination were more than 2 times higher in treatment group than in control group (P<0.02), but vaccination did not significantly reduce infection or improve pregnancy in heifers when exposed to Cfv-infected bulls. Sample preparation technique is important for successful real-time PCR; release of DNA directly from a CVM sample by a modified heat lysis protocol was easy to perform and could be promising as a rapid screening approach for Bovine Genital Campylobacteriosis after validating on fresh samples. Vaccinating of heifers with a polyvalent commercial vaccine, containing Campylobacter fetus antigen, according to the label, did not significantly reduce infection rate or improve reproductive performance when they were naturally challenged.
15

Identification de gènes impliqués à la fois dans le dépôt de gras dorsal et le contrôle de certains caractères de reproduction chez le porc

Lord, Étienne January 2005 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.
16

Effects of nicotine on GABAA subunit expression in the rat brain

Bergenheim, Veronica January 2007 (has links)
<p>Smoking is a worldwide problem and it is the second major cause of death. People often try to quit, but few succeed mainly because of withdrawal symptoms such as irritability, anxiety, increased appetite, hyperventilation and difficulty concentrating.</p><p>The overall aim of this project was to study neurochemical changes in the brain following sensitization to nicotine which could give more information about what causes an individual to go from using drugs to abusing the drugs. Therefore, we investigated messenger ribonucleic acid (mRNA) expression of several genes known to be involved in the mesolimbic dopamine pathway in the nucleus accumbens, caudate putamen, prefrontal cortex and medial prefrontal cortex using real-time polymerase chain reaction (real-time PCR).</p><p>The results showed that in the nucleus accumbens, mRNA expression of gamma-aminobutyric acid (GABA) Aα1 subunit receptor and GABA transporter 3 (GAT-3) were significantly increased following nicotine administration, while in the caudate putamen no difference in expression was observed. In prefrontal cortex, the expression of adrenergic subunit receptor α2A was significantly increased following hexamethonium administration. In medial prefrontal cortex a significant decrease of expression of GAT-1 was shown following nicotine and hexamethonium administration, while a decrease of CART expression only was shown following nicotine administration.</p><p>Overall, these changes in the GABA system may help to explain the mechanism of nicotine sensitization.</p>
17

Establishment, identification, quantification of methanogenic archaea in chicken ceca and methanogenesis inhibition in in vitro chicken ceca by using nitrocompounds

Saengkerdsub, Suwat 16 August 2006 (has links)
In the first phase of this study, the diversity of methanogenic bacteria in avian ceca was found to be minimal. Based on 16S rDNA clone libraries, a common phylotype, designated CH101, ranged between 92.86 to 100 % of the total clones whereas less than 1% of the other phylotypes were found. On the basis of the sequence identity, all of the sequences, except sequence CH1270, are related from 98.97 to 99.45% to 16S rDNA Methanobrevibacter woesei GS. Sequence CH1270 is 97.62% homologous to the sequence identified to uncultured archaeon clone ConP1-11F. Clearly, the predominant methanogen found to reside in the chicken ceca was M. woesei. By using a MPN enumeration method, methanogen counts were found to be in the range of 6.38 to 8.23 log10 organisms per gram wet weight. The 16S rDNA copy number per gram wet weight in the samples was between log10 5.50 and 7.19. The second phase of the study was conducted to observe the effects of selected nitrocompounds and two different feedstuffs on in vitro methane production in chicken cecal contents and rumen fluid. Initially, one of the three nitrocompounds was added to incubations containing cecal contents from laying hens supplemented with either alfalfa or layer feed. Both feed materials influenced volatile fatty acids (VFA) production and also fostered methane production in the incubations although methane was lower (P < 0.05) in incubations with added nitrocompound, particularly nitroethane. Secondly, nitroethane was examined in incubations of bovine or ovine rumen fluid or cecal contents containing either alfalfa or layer feed. Unlike cecal contents, layer feed significantly (P < 0.05) supported in vitro methane production in incubations of both rumen fluids. The results show that nitroethane impedes methane production, especially in incubations of chicken cecal contents. The final phase of this study was carried out to determine the methanogenic establishment in the chicken ceca by the cultural method with the quantitative PCR. The results suggested that methanogens colonized in chicken ceca at a few days after birth. Litter and house flies could be potential sources for methanogenic colonization in broiler chicks.
18

Optimization and validation of the method lactose intolerance genotyping with real-time PCR

Stenberg, Jenny January 2011 (has links)
Abstract Primary lactose intolerance has been associated with a single nucleotide polymorphism located upstream of the lactase gene. The most common diagnostic tests for lactose intolerance are time-consuming and the patient is not allowed to eat and drink for 12 hours before the test is carried out. A method that can establish the genotype would be an easier way of diagnosing lactose intolerance compared to fenotypic lactose intolerance tests. Optimization and validation of a previously published method was performed with real-time polymerase chain reaction. We used whole blood from de-identified blood donors. During the optimization and validation we used a positive control, genotype C/T from Laboratoriemedicin Västernorrland, Sundsvall. The whole-blood was extracted using the MagNa Pure LC instrument. The reagent used was KAPA PROBE FAST qPCR Master Mix. The optimized program for real-time PCR was established to be 95°C 3min [95°C x 3sec, 55°C x 20sec, detection, 72°C x 15sec] x 50 cycles. Optimal probe concentration was found to be 0.2µM and primer concentration will be 0.5µM. This genotyping method is a good first-stage screening test for lactoseintolerance. Before it can be used as a routine method further validation will be necessary in order to ensure that the evaluation of the results can be done in an easy and secure way.
19

Microbial bioremediation and monitoring of a TCE-contaminated site

Li, Kuan-hsun 11 July 2011 (has links)
The goal of this study was to use molecular biology techniques to access and monitor the efficacy of bioremediation on a trichloroethene (TCE) polluted site. We added emulsified hydrogen releasing materials to stimulate onsite microbial growth and the biodegradation of TCE. This process was known as enhanced bioremediation. In this study, there were two bioremediation sites had been treated anaerobically. Groundwater samples were taken periodically for microbial analysis. Denaturing gradient gel electrophoresis (DGGE) was used to evaluate the variations in microbial community structures during the in situ groundwater remediation. The DGGE DNA bandings were sequenced to determine the 16S rRNA gene sequences and identify the dominate bacterial species. In addition, we used Dehalococcoides spp. 16S rRNA genes as the targets to do real-time PCR. Results show that the emulsified hydrogen releasing materials could enhance anaerobic reductive dechlorination. After addition of emulsified hydrogen releasing materials, we found that the volatile organic compounds concentrations (i.e., TCE, 1, 1-DCE and VC) were decreased. In microbial analysis, the diversities of the microbial community were increased after nutrient supplement. According to the DNA sequencing results, there were 31 bacterial species had been found that related to TCE degradation (i.e., Acidovorax sp., Burkholderiales, Pseudomonas sp., £]-proteobacterium, Comamonadaceae, Iron-reducing bacterium, Hydrogenophilaceae, Clostridium sp., Geobacter sp., Rhodoferax ferrireducens, Dehalospirillum multivorans and Dehalococcoides spp.). Dehalococcoides spp. can be used as a biomarker to evaluate the efficacy of anaerobic bioremediation on a TCE contaminated site. Therefore, we quantified Dehalococcoides populations to explain the capacity of bioremediation after addition of emulsified hydrogen releasing materials to groundwater. Results reveal that Dehalococcoides cell numbers of site A were 4.47¡Ñ103-8.26¡Ñ104 CFU/liter, site B were 4.60¡Ñ102-9.31¡Ñ107 CFU/liter. This data indicated that the addition of emulsified substrate would increase the growth of total Dehalococcoides population under anaerobic conditions. Overall, results from this study demonstrated that the microbial analysis and quantities of Dehalococcoides at different time points can provide useful information to proceed with bioremediation methods.
20

Microcosm batch study of the degradation of 1,2-DCA-contaminated soil

Huang, Chih-wei 23 July 2012 (has links)
1,2-dichloroethane (1,2-DCA) is a popular industrial chlorinated organic chemical. Because 1,2-DCA is a dense non-aqueous phase liquid and easily accumulated in deep soil and water, it is difficult to be removed from the contaminated sites. In this study, aerobic and anaerobic microcosm batch experiments were performed to evaluate the feasibility of biodegradation of 1,2-DCA by adding different growth substrates. The aerobic microcosm results show that approximately 90% of 1,2-DCA removal was observed in the natural degradation group (A1) and the aerobic sludge addition group (A3) after 7 days of incubation. Up to 95% of 1,2-DCA removal could be observed in the substrate supplement group in after 14 days of incubation. In the anaerobic microcosm studies, 50% of 1,2-DCA removal could be obtained in all groups after 10 days except for the natural degradation group (B1). Moreover, the degradation efficiency for the anaerobic sludge group (B3) reached 80% of 1,2-DCA removal in 5 days. The DGGE profiles show that the microbial diversity varied with time and the sugar supplement groups (A2, B2) exhibited the most microbial diversity. Bacterial clones results revealed that the 1,2-DCA biodegradable microbial strains were presented in the microcosms, such as Klebsiella, Pseudomonas, Rhodoferax and Xanthobactor. The real-time PCR results indicated that the Dehalococcoides spp. was the major bacterium that was responsible for the degradation of 1,2-DCA in the anaerobic substrate supplement group (B2). Desulfitobacterium spp. could be the dominant 1,2-DCA degrading bacterium for the aerobic substrate supplement group (A2) and all of the anaerobic groups (B1, B2, B3, B4).

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