• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 16
  • 6
  • 5
  • 5
  • 5
  • 5
  • 5
  • 5
  • 5
  • 2
  • 1
  • Tagged with
  • 45
  • 45
  • 24
  • 11
  • 9
  • 8
  • 8
  • 6
  • 6
  • 6
  • 5
  • 4
  • 4
  • 4
  • 4
  • 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.
41

Genome-wide association studies reveal genomic regions and positional candidate genes for fat deposition in chickens / Estudos de associação genômica ampla revelam regiões genômicas e genes candidatos posicionais para deposição de gordura em galinhas

Gabriel Costa Monteiro Moreira 09 March 2018 (has links)
Excess of fat deposition is a negative factor for poultry production, which affects feed efficiency and consequently the costs of meat production. The incorporation of genomic tools in poultry breeding programs may help to accelerate the selection for increased production efficiency. In this context, we genotyped approximately 2,000 42 days-old chickens from two different populations (Brazilian F2 Chicken Resource population and TT broiler Reference Population) using a high-density SNP array (600K, Affymetrix) to estimate genomic heritability of fatness-related traits, to identify genomic regions and positional candidate genes (PCGs) associated with these traits. We performed genome-wide association (GWAS) analysis using GenSel software (Bayesian approach) to identify 1 Mb genomic windows associated with abdominal fat, skin and carcass fat content traits. The search for PCGs were made within each genomic windows associated considering their Gene Ontology (GO) terms and also the literature information. We also integrated into this study NGS-SNPs data from both populations and selection signature regions identified in Brazilian F2 Chicken Resource population to refine the list of PCGs. The genomic heritability values for fatness-related traits were from moderate to high (greater than 0.30). We identified quantitative trait loci (QTL) for abdominal fat, skin and carcass fat content traits harboring several PCGs involved in biological processes of fat deposition. We identified several NGS-SNPs annotated in potential functional regions in our PCGs and some of those were predicted as deleterious and high impact mutations. Besides that, some genes overlapped with selection signature regions in Brazilian F2 Chicken Resource population. Important candidate genes for fat deposition were identified, providing new insights to achieve a better understanding of the genetic control of fat deposition in chickens. / O excesso de deposição de gordura é um fator negativo para a produção de aves, o que afeta a eficiência alimentar e consequentemente os custos da produção de carne. A incorporação das ferramentas genômicas em programas de melhoramento de aves pode ajudar a acelerar a seleção para aumentar a eficiência da produção. Neste contexto, genotipamos cerca de 2.000 aves de 42 dias de duas populações diferentes (população F2 experimental brasileira e população de corte referência TT) usando um chip de SNPs de alta densidade (600K, Affymetrix) para estimar a herdabilidade genômica de características relacionadas à deposição de gordura, para identificar regiões genômicas e genes candidatos posicionais (PCGs) associados a essas características. Realizamos análises de associação genômica ampla (GWAS) usando o programa GenSel (abordagem Bayesiana) para identificar janelas genômicas de 1 Mb associadas com características de gordura abdominal, pele e conteúdo de gordura na carcaça. A busca por PCGs foi feita dentro de cada janela genômica associada, considerando os Gene Ontology (GO) terms e também a informação da literatura. Integramos neste estudo NGS-SNPs identificados em animais parentais de ambas as populações, e além disso, regiões de assinaturas de seleção identificadas na população F2 experimental brasileira para refinar a lista de PCGs. Os valores de herdabilidade genômica para as características relacionadas à gordura foram de moderado a alto (maior que 0,30). Identificamos QTL para características de gordura abdominal, pele e conteúdo de gordura na carcaça contendo PCGs envolvidos em processos biológicos de deposição de gordura. Identificamos vários NGS-SNPs anotados em regiões potencialmente funcionais em nossos PCGs e alguns desses foram preditos como mutações deletérias e de alto impacto. Além disso, alguns genes se sobrepuseram com regiões de assinatura de seleção na população F2 experimental brasileira. Foram identificados importantes genes candidatos para a deposição de gordura, fornecendo novos insights para alcançar uma melhor compreensão do controle genético da deposição de gordura em frangos.
42

Jakostní parametry trvanlivých fermentovaných masných výrobků / Quality parameters of dry fermented sausages

Pavlík, Zdeněk January 2012 (has links)
The aim of this study was to evaluate quality parameters of dry fermented sausages. Samples of two types of dry fermented sausages were sampled – sausage “Poličan“ and “Lovecký salám“, from three different producers. Basic physical-chemical analysis of quality parameters were performed in sausage mixture and immediately after end of ripening (21 days for Poličan and 16 days for Lovecký salám). Results of quality parameters analysis were compared with requirements of Czech legislation and differences between producers were observed. There were significant differences between producers, however all of them met requirements set by 326/2001 Czech notification as amended of Ministry of agricultural.
43

The inhibitory effect of trans fatty acids on maternal and neonatal essential fatty acid metabolism.

January 1997 (has links)
by Kwan Kwok Yiu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 145-155). / Acknowledgment --- p.i / Abstract --- p.ii / List of Tables --- p.vii / List of Figures --- p.x / List of Abbreviations --- p.xii / Chapter Chapter 1 --- Literature review / Chapter 1.1 --- Historical background --- p.1 / Chapter 1.2 --- Chemistry of trans and cis fatty acids --- p.3 / Chapter 1.3 --- Dietary source of trans fatty acids --- p.6 / Chapter 1.4 --- Consumption of trans fatty acids among Western countries --- p.9 / Chapter 1.5 --- Current health concern for excessive intake of trans fatty acids --- p.10 / Chapter 1.6 --- Metabolism of trans fatty acids --- p.13 / Chapter 1.6.1 --- Absorption --- p.15 / Chapter 1.6.2 --- Oxidation --- p.15 / Chapter 1.6.3 --- Incorporation --- p.16 / Chapter 1.6.4 --- Selectivity --- p.17 / Chapter 1.7 --- Impact of trans fatty acids on essential fatty acid metabolism --- p.19 / Chapter 1.8 --- Desaturation and elongation of trans fatty acids --- p.21 / Chapter 1.9 --- Trans fatty acids and neonatal growth --- p.23 / Chapter Chapter 2 --- Amount of trans fatty acids in Hong Kong fast foods / Chapter 2.1 --- Introduction --- p.25 / Chapter 2.2 --- Objective --- p.25 / Chapter 2.3 --- Materials and methods --- p.26 / Chapter 2.4 --- Results --- p.27 / Chapter 2.5 --- Discussion --- p.31 / Chapter Chapter 3 --- Cross-cultural study of trans fatty acids in human milk / Chapter 3.1 --- Introduction --- p.35 / Chapter 3.2 --- Objective --- p.35 / Chapter 3.3 --- Materials and methods --- p.36 / Chapter 3.4 --- Results / Chapter 3.4.1 --- Dietary information --- p.38 / Chapter 3.4.2 --- Fatty acid composition of Chinese and Canadian human milk --- p.40 / Chapter 3.4.3 --- Difference between Chinese and Canadian human milk --- p.40 / Chapter 3.4.4 --- Difference between Hong Kong and Chongqing Chinese human milk --- p.43 / Chapter 3.4.5 --- The change in milk fat and LCPUFA as lactation progresses --- p.43 / Chapter 3.5 --- Discussion / Chapter 3.5.1 --- Trans fatty acids in human milk --- p.46 / Chapter 3.5.2 --- Content of LCPUFA in human milk --- p.47 / Chapter 3.5.3 --- Content of 18:2n-6 in human milk --- p.48 / Chapter 3.5.4 --- Fat content in Hong Kong and Chongqing Chinese human milk --- p.49 / Chapter 3.6 --- Conclusion --- p.50 / Chapter Chapter 4 --- Trans fatty acids and maternal and neonatal essential fatty acid metabolism / Chapter 4.1 --- Introduction --- p.51 / Chapter 4.2 --- Objectives --- p.53 / Chapter 4.3 --- Materials and methods --- p.53 / Chapter 4.4 --- Results / Chapter 4.4.1 --- Experiment1 / Chapter 4.4.1.1 --- Relationship between the trans fatty acids in maternal diet and those in milk --- p.64 / Chapter 4.4.1.2 --- Relationship between the trans fatty acids in maternal diet and those in neonatal liver --- p.64 / Chapter 4.4.1.3 --- Content of 20:4n-6 in milk and in neonatal liver relative to that in maternal diet --- p.72 / Chapter 4.4.2 --- Experiment2 / Chapter 4.4.2.1 --- Amount of trans fatty acids in rat milk --- p.75 / Chapter 4.4.2.2 --- Trans fatty acids in rat liver phospholipids --- p.75 / Chapter 4.4.2.3 --- Linoleic acid (18:2n-6) content in rat and its relation to maternal diets --- p.86 / Chapter 4.4.2.4 --- Content of 20:4n-6 in rat milk --- p.86 / Chapter 4.4.2.5 --- Content of20:4n-6 in rat liver --- p.89 / Chapter 4.4.2.6 --- Suppression of the synthesis of 20:4t isomers in maternal and neonatal liver --- p.89 / Chapter 4.5 --- Discussion / Chapter 4.5.1 --- Relationship between fatty acid composition of diet and that of milk --- p.93 / Chapter 4.5.2 --- 20:4n-6 in rat milk --- p.95 / Chapter 4.5.3 --- Transfer of trans fatty acids from maternal diet to neonatal liver phospholipids --- p.98 / Chapter 4.5.4 --- The inhibitory effect of trans fatty acids on synthesis of 20:4n-6 in neonatal liver --- p.99 / Chapter 4.5.5 --- Effect of 18:2n-6 supplement on 20:4n-6 level of neonatal liver --- p.101 / Chapter 4.5.6 --- Suppression of 18:2n-6 supplement on synthesis of 20:4t isomers --- p.101 / Chapter 4.6 --- Conclusion --- p.104 / Chapter Chapter 5 --- Accumulation and turnover of trans fatty acids / Chapter 5.1 --- Introduction --- p.105 / Chapter 5.2 --- Objective --- p.105 / Chapter 5.3 --- Materials and methods --- p.106 / Chapter 5.4 --- Results / Chapter 5.4.1 --- Accumulation of trans fatty acids in liver and adipose tissue --- p.108 / Chapter 5.4.2 --- Selectivity of individual 18:2 trans isomersin liver and adipose tissue --- p.112 / Chapter 5.4.3 --- Turnover of trans fatty acids --- p.112 / Chapter 5.4.4 --- Accumulation and turnover of 18:lt in brain --- p.115 / Chapter 5.5 --- Discussion / Chapter 5.5.1 --- Accumulation of trans fatty acids in liver and adipose tissue --- p.120 / Chapter 5.5.2 --- Turnover of trans fatty acids --- p.122 / Chapter 5.5.3 --- Accumulation and turnover of trans fatty acidsin brain --- p.124 / Chapter 5.6 --- Conclusion --- p.125 / Chapter Chapter 6 --- In vivo Oxidation of trans fatty acids in rat / Chapter 6.1 --- Introduction --- p.126 / Chapter 6.2 --- Objective --- p.127 / Chapter 6.3 --- Materials and methods --- p.127 / Chapter 6.4 --- Results --- p.129 / Chapter 6.4.1 --- Apparent oxidation of saturated fatty acids --- p.136 / Chapter 6.4.2 --- Apparent oxidation of 18:lt relative to 18:ln-9 --- p.136 / Chapter 6.4.3 --- Oxidation of 18:2t isomers relative to 18:2n-6 --- p.137 / Chapter 6.4.4 --- Effect of 18:2n-6 supplement in PHCO diet on oxidation per se --- p.137 / Chapter 6.5 --- Discussion --- p.138 / Chapter 6.5.1 --- Oxidation of 18:lt and 18:2t isomers --- p.139 / Chapter 6.5.2 --- Effect of 18:2n-6 supplement on oxidation per se --- p.140 / Chapter 6.6 --- Conclusion --- p.141 / General conclusion --- p.142 / References --- p.145
44

The influence of diet on plasma glucose, insulin, triglyceride, and free fatty acid concentrations in healthy dogs

Kathryn Elliott Unknown Date (has links)
Diabetes mellitus is a frequent endocrinopathy in dogs. Exogenous insulin and nutritional management are the mainstays of therapy. High carbohydrate and fibre diets have been traditionally recommended for canine diabetes mellitus. However, recent studies in healthy and diabetic dogs have challenged the use of these traditional diabetic diets. In addition, dietary carbohydrate content was found to be the main determinant of postprandial blood glucose concentrations over 1.5 hours in healthy dogs. Increasing carbohydrate content increased blood glucose concentration. In a search of the literature, no studies in dogs were found comparing the effects on postprandial plasma glucose, insulin, triglyceride and free fatty acid concentrations of a traditionally recommended high carbohydrate and fibre diabetes diet with a moderate carbohydrate and fibre diet, or a commercially-available maintenance diet. Although fasting plasma triglyceride concentrations are commonly used for diagnosis and management of canine hyperlipidemia, a review of the literature found that in human beings, it may not to be predictive of the highest postprandial concentration. Importantly, in overweight and obese dogs with postprandial plasma triglyceride concentrations >5 mmol/L (>445 mg/dL), it was found there was a 6 fold increase in risk of laboratory evidence of exocrine pancreatic disease. However, there are limited studies on the effect of maintenance diets on postprandial plasma triglyceride concentrations in dogs, and no reference intervals determined for a triglyceride meal challenge test in healthy dogs. For the dietary studies in this thesis, animal welfare was of paramount importance, and minimally invasive peripheral venous catheterization and blood collection techniques were needed to collect 4 mL blood samples over 13 hours in conscious dogs. A search of the literature found no studies evaluating the reliability of using peripheral catheterization via the cephalic vein for the collection of larger blood volumes (for example, 4 mL). The aims of this thesis were firstly, to investigate the influence of three diets with varying carbohydrate and fibre content on postprandial plasma glucose, insulin, triglyceride and free fatty acid concentrations in healthy dogs over 12 hours; secondly, to develop a triglyceride meal challenge test and associated reference intervals; and finally, to evaluate a minimally invasive catheterization and blood collection technique for reliability in collecting the blood volumes required for these studies. For the studies in this thesis, twelve healthy dogs were fed each of three diets for three weeks in a three period cross-over design. For the meal response test at the end of each three-week period, 10 blood samples were collected over 13 hours. Reference intervals for fasting and postprandial triglyceride concentrations at single and multiple time points after eating a standard meal were determined in healthy dogs. Associations between fasting and postprandial triglyceride concentrations, and time to measure highest postprandial triglyceride concentration were also evaluated. Blood volume obtained, resistance on aspirating the blood sample, and methods used to improve blood flow during collection were recorded for the 358 samples collected. The results of the studies in this thesis demonstrated that a moderate carbohydrate diet resulted in lower peak and postprandial glucose concentrations compared with a traditional diabetic diet (CHO 55 %ME) and a maintenance diet (CHO 45 %ME). Fasting triglyceride concentrations were found not to be predictive of peak postprandial triglyceride concentrations. The highest triglyceride concentration measured at 2, 5, and 6 hours after eating had the closest agreement with peak postprandial triglyceride concentration. Glucose, insulin and triglyceride concentrations in some dogs were significantly above baseline concentrations at 12 hours after eating each of the diets. Of 358 blood samples collected, 93 % achieved the required 4 mL volume, while the remaining samples were greater than 1.5 mL, and 87 % were obtained with minimal resistance. It was concluded that the moderate carbohydrate and fibre test diet warrants evaluation in diabetic dogs. It was found that when following the same protocol, blood samples should be collected 2, 5, and 6 hours after eating to determine the highest postprandial plasma triglyceride concentration. For future nutritional studies, dogs may need to be fasted for at least 12 hours, and analytes measured over at least 12 hours after feeding to evaluate fasting and postprandial plasma analyte concentrations. Finally it was demonstrated that percutaneous catheterization of the cephalic vein using a 20-gauge catheter allows for successful collection of multiple 4 mL blood samples over 13 hours in conscious dogs. This thesis presents new information for future nutritional studies in healthy and diabetic dogs by suggesting that there may be no glycemic benefit feeding the high carbohydrate and fibre diet compared with a moderate carbohydrate and fibre diet. A triglyceride meal challenge test was developed to assist the diagnosis of canine hyperlipidemia. Finally, a minimally invasive method for obtaining serial blood samples was evaluated and described. These findings are expected to help in designing future studies in the nutritional management in healthy dogs, and dogs with diabetes mellitus and hyperlipidemia.
45

Inzulínová rezistence a postprandiální stav u diabetu 2. typu. Vliv frekvence a složení jídel na metabolismus glukózy a další projevy metabolického syndromu / Insulin resistance and postprandial state in type 2 diabetes. The effect of meal frequency and composition on glucose metabolism and other manifestations of the metabolic syndrome

Thieme, Lenka January 2017 (has links)
The project focuses on dietary interventions in type 2 diabetes(T2D). The aim was to investigate how glucose metabolism and other manifestations of insulin resistance should be influenced by a) the composition of macronutrients and b) frequency of meals; and to characterize the possible mechanisms of these dietary interventions in patients with T2D. A. In a randomized crossover study, 50 patients T2D and 50 age-matched healthy subjects underwent in a random order meal tolerance tests with three isocaloric meals (vegan sandwich; V-meal, hamburger; M-meal, or cheese sandwich; S-meal. Blood samples for analysis were taken at time 0 and after 30, 60, 120 and 180 minutes after meal ingestion. Plasma concentrations of plasma glucose, insulin, C-peptide, lipids, oxidative stress markers and gastrointestinal hormones (GIHs) were investigated. Both basal and postprandial plasma concentrations of glucose and insulin were significantly higher in patients with T2D (p<0.001); basal and postprandial concentrations of almost all other GIHs (except for ghrelin) and thiobarbituric acid reactive substances (TBARS) were significantly increased (p<0.001), while ascorbic acid, reduced glutathione and superoxide dismutase activity were decreased in patients with T2D compared to healthy controls (p<0.001). The meal rich...

Page generated in 0.099 seconds