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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.
101

Vliv před-fermentační macerace na obsahové látky moštu révy vinné

Sapík, Miloslav January 2014 (has links)
Data shows that if the year is similar to year 2013, as regards to the increased content of titratable acid, there can be a longer maceration pulp, which may serve as the future harmoniousness wine. Appropriate sufficient time of maceration for any decrease in titratable acidity corresponds to the period of maceration form 4 to 12 hours. Regarding the tartaric acid and malic acid, the time of maceration appears to be approximately 8 hours. From this time forth there may be rises in values of malic acid,which can cause microbiological instability. If we wanted to get the largest share of the health-promoting substances of this year, the must had to be macerated at least 48 hours.
102

Závislost obsahu vybraných kovů na množství a kvalitě organické hmoty v půdě

Janovský, Jakub January 2015 (has links)
The aim of the experiment was to assess the dependence of selected metals (Fe, Cu, Zn, Mn, Ni and Pb) for the quantity of organic matter and its quality on arable land. Soil sampling was conducted in Starý Hrozenkov and Žítková, located in the White Carpathians. Soil samples were collected during the growing season of 2012, on a monthly basis (April to October) from a depth of 0-30 cm. To determine the content of available metals by AAS, soil samples were extracted with 2M HNO3. Determination of the amounts of soil organic matter was performed by an oxidometric method (Cox), for determining the monitored fractions of soil organic matter (humic substances, humic and fulvic acids) was used the method of short fractionation. The results of analyzes of soil samples revealed that the supply of all monitored metals was in Žítková lower than in Starý Hrozenkov. Like the metal was also the quantity of each fractions of soil organic matter at the site Žítková lower than in the soil Starý Hrozenkov. In both localities were found a positive correlation between Cox and almost all the monitored elements. In soil in Žítková was found medium strong dependence metals (r = 0.4339 to 0.6675) on the content of humic substances in soil and medium dependence Zn, Cu and Fe on fulvic acids. In the Starý Hrozenkov was medium dependence Pb, Ni and Mn on humic acids and medium strong dependence Fe on fulvic acids (r = 0.4459).
103

Porovnání kvalitativních ukazatelů odrůd chmele otáčivého (Humulus lupulus) z různých typů chmelnic / Comparison of qualitative indicators varieties of hops (Humulus lupulus) from various types of hop fields

KORCOVÁ, Žaneta January 2016 (has links)
The aim of this thesis was to determine content of - a -bitter acids in samples of hop obtained from different types of growing regions. Object of research were cultivars of Saaz late, Sládek and Premiant cultivated in three growing regions (Žatecko, Úštěcko, Tršicko) in year 2015. Nine hop samples from conventional agriculture and one from bio production were examined. For all growing areas, from which hop cones were obtained, was determined altitude, rainfall and average temperatures during vegetation period. Quantity of bitter acids were measured by HPLC. Our calculated correlation coefficients showed that the higher altitude and average temperature the lower content of bitter acids was measured and more precipitation has positive impact on content of bitter acids.
104

Odolnosť ľudského pachu voči chemickým detergentom / Ability of dogs to discriminate human odor exposed to chemical detergent

Čajágiová, Martina January 2016 (has links)
In the recherche part of our thesis we familiarize ourselves with the human odor, theories of its origin, definition, anatomy of human skin and odors, composition of individual human odors and with odor secretion. We also look closer on the topics of odor absorbent and its use in the world, the transmission of odors to odor sensors and securing of scents. This section of our thesis discusses the resistance and survival abilities of odor, scent identification method and its history, organic acids, and defines the application of laundry detergents and ultrasonic washers. Aim of our thesis was to verify the relevance of the use of chemical detergents in the purification process when working with scents. We tried to verify the ability of detergents to degrade the human scent on odor absorbents to such an extent, that specially trained dogs would not be able to identify it. Our experiment was following a precise determination methodology. In the first phase samples were collected from the hands of targeted persons to a scent carrier - a metal cylinder (extirpate odour), by one researcher. In the second phase samples were collected from the body to a textile carrier, by another researcher. The metal scent carriers were processed. Some of them were left as they were (control sample) and some were exposed to chemical detergents with and without usage of an ultrasonic washer. In the experiment where we tried to identify the odour samples, six bitches of German shepherd were used. They were specially trained for odour identification. Each dog was let three times to identify the target scent exposed to a detergent and three times to identify the target scent not exposed to a detergent. Target smell was randomly deposited between other samples and its position was changed, so that the handler did not know its position and thus was unable to affect the work of his dog. The indicator of positive identification was a sign the dogs were taught - to sit or lay in front of a sample. Any dog was unable to identify the scent which was exposed to chemical detergent and all dogs identify the scent unexposed to a chemical detergent. Our experiment has shown that the use of chemical detergents in the purification process when working with scents is relevant to the degradation of individual human scent.
105

Účinky xenobiotik na oxidační stres, metabolizmus lipidů, integritu DNA a životaschopnost lidských buněk a rybích spermií in vitro

LINHARTOVÁ, Pavla January 2016 (has links)
Pollution of the aquatic environment by inorganic and organic chemicals is a major factor posing a serious threat to the survival of aquatic organisms including fish. In addition balancing risks and benefits of fish consumption is nowadays an intensively discussed public health topic. Spermatozoa of almost all fish species are released into water environment where they can be directly exposed to various compounds, such as xenobiotics including toxic metals, prior to fertilization. In addition, exposure of parental adults to various xenobiotics may affect gamete quality, which may subsequently reduce fertilization success. On the other hand the advantages of eating fish are well-known, not only in the point that fish is a healthy source of protein and other nutrients, but eating contaminated fish may also confer various health benefits. Research over the past few decades has shown that the nutrients and particularly the n-3 fatty acids (FA) found in fish and seafood, are for examples protective against cardiac diseases and have a positive impact on brain development. The thesis provides a focus on two different cell model types. Firstly, human hepatocellular cells (Hep G2, ATCC) were used as in vitro tool for studying the effect of the intake of cadmium (Cd2+) contaminated fish on cytotoxicity, oxidative stress and fatty acid and phospholipid class compositions. Secondly, spermatozoa of one threatened species of fish, sterlet (Acipenser ruthenus) were used as in vitro model for studying effect of potentially hazardous xenobiotic compounds' occurring in open waters. Sperm from sterlet were exposed for 2h to environmentally relevant concentrations of DQ (0-150
106

Vliv polymorfismu kandidátního lokusu na technologické vlastnosti mléka

MIJAILOVIĆ, Angelina January 2017 (has links)
The aim of this thesis is to analyze the influence of polymorphic variants of selected locus (SCD) on the technological quality of milk. At the beginning is described, milk yields along with the mammary gland - structure, diseases associated with it, colostrum and milk production. The composition of milk includes fat, fatty acids, carbohydrates, minerals, vitamins, proteins - whey protein (-lactoglobulin, -lactalbumin), casein (-casein, -casein, -casein) The thesis also deals with the genome of cattle, genetic markers, candidate loci. Methodology describes DNA isolation, PCR, including PCR for SCD, RFLP, and determination of fatty acids by spectrophotometry. At the end of the thesis are the results, which evaluate the genotypes and alleles abundance, the milk performance indicators depending on the genotype for SCD and the evaluation of the influence of the SCD genotype on the fatty acid spectrum.
107

Stanovení mastných kyselin ve vybraných živočišných tkáních

Piknerová, Tereza January 2016 (has links)
My thesis consists of a theoretical part and a practical part. In theoretical part I deal with information about the fatty acids and its structure, functions and influence on our health. Last but not least I focused on diseases that may arise due to bad intake of fatty acids. It is the atherosclerosis. The second part of my thesis is the already mentioned practical part. This consisted of a samples of pigs in which were taken all animal tissues and subsequent determination of the fatty acids. In my thesis I deal with liver and muscle tissue. These samples were taken from pigs that had fish or palm oil in the diet. The determination was done by lyophilization, extraction, derivatization and gas chromatography. Based on the results, I conducted a statistical evaluation using graphs and a final evaluation of the results.
108

Farmakokinetika flavanolů / Pharmacokinetics of flavanols

Sobolová, Dominika January 2018 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Dominika Sobolová Supervisor: Assoc. Prof. Přemysl Mladěnka, Pharm.D., Ph.D. Title of diploma thesis: Pharmacokinetics of flavanols This work is focusing on summarizing available information about the fate of flavanols in the organism. It is necessary to know the pharmacokinetics to explain their biological effects. In contrast to other flavonoids, they occur in the form of aglycones in plant foods. Galoylation, polymerization and optical isomerism have an important influence on the pharmacokinetics. Partial absorption of monomers begins in the small intestine after oral ingestion. In addition to the liver, the extensive metabolic changes take place even in the enterocytes. The resulting metabolites enter the circulation or they are effluxed back into the intestinal lumen, especially in the case of (epi)catechin sulfates. Epicatechin and catechin are present almost exclusively as glucuronides, sulfates or methylated compounds in the plasma. On the contrary, free unconjugated forms prevail within the gallates. The extent of their absorption is lower. They are excreted via biliary excretion, while other catechins are quickly eliminated by the kidneys in urine. The bioavailability of the parent...
109

Faktory ovlivňující zastoupení mastných kyselin v mase ryb

Kladroba, David January 2003 (has links)
No description available.
110

Listová zelenina jako zdroj výživově významných fenolických látek / Leaf vegetable as a source of phenolic compounds with nutritional value.

TRÖSTLOVÁ, Daniela January 2013 (has links)
The present work treats the amount of phenolic substances in salad plants. A part of this vast plant group is made of flavonoids, which are important by their accessibility and significant biological activity. Quercetin and rutin are in the main focus of this work. They are noted for their favourable biological effects. Having antioxidant qualities, they prevent and stop the lipid peroxidation and they dispose of free radicals. Flavonoids are used in medicine and can prevent the formation of chronic diseases, such as cardiovascular disease or atherosclerosis. The amount of phenolic substances in the chosen sample of ten salad plants was determined by means of micellar electrokinetic capillary chromatography (MECC) and by high-performance liquid chromatography (HPLC). We have used a freeze-dried material for the analysis. The utmost amount of quercetin was found in lettuce grown on outside garden. 48 600 mg/kg of dry matter highly exceeded the amount of quercetin in other plants. There were other phenolic substancs as well: rosmarinic acid, caffeoylchinol acid and caffeic acid. Among others, we found derivatives and colourants of caffeic acid as well.

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