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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

Untersuchungen in ternären chalkogenhaltigen Systemen Ag-Ga-Te und Sn-Sb-Se

Shen, Jun. Unknown Date (has links) (PDF)
Universiẗat, Diss., 2002--Osnabrück.
32

Investigation of the nuclear structure of 69As and 69Se with the EUROBALL spectrometer

Stefanescu, Irina Stefania. Unknown Date (has links) (PDF)
University, Diss., 2004--Köln.
33

Anti-depressives Potential der Selen- Supplementation in Verbindung mit der Gabe von Antioxidantien, Spurenelementen und Mineralstoffen

Mühlhausen, Klaus 09 January 2017 (has links) (PDF)
Einleitung Melancholische Phase und Depression haben viele Ursachen. Neurotransmitter wie Serotonin, Hormone (Schwangerschaft), Spurenelemente wie Zink, oder unterschwellige Entzündungen (silent inflammation) spielen eine Rolle in der Pathogenese. Es gibt Hinweise für die Rolle des Spurenelementes Selen, insgesamt ist aber wenig darüber bekannt, ob Selen bei Stimmungsstörungen oder depressiven Phasen wirken könnte. Die untersuchte Multivitamin- und Spurenelement-Mischung Lavita® enthält unter anderem das Spurenelement Selen gebunden in organischer Matrix. Ziel der vorliegenden Arbeit war es, Befunde zur Selen-Wirkung bei klinisch relevanten depressiven Zustandsbildern systematisch zu recherchieren, und in Verbindung mit einer Feld-Studie das Wirkpotential von Selen in der der Prüfsubstanz zu beschreiben. Methode Der Studie ging eine ausführliche Literaturrecherche in medizin-wissenschaftlichen Datenbanken voran. Das Studiendesign wurde von der Internationalen Gesellschaft für Präventionsmedizin e.V. (Augsburg, Deutschland) und der Studien-Supportfirma SCIgenia (Wien, Österreich) entwickelt. Gemäß Ein- und Ausschlusskriterien wurden 30 gesunde Probanden rekrutiert. Vor der ersten Einnahme wurden Basis-Blutwerte abgenommen, eine weitere Blut-Abnahme erfolgte nach drei Monaten, die Studienabschlussvisite mit der 3. Blutabnahme fand nach insgesamt sechs Monaten regelmäßiger Einnahme der Prüfsubstanz statt. Die Blut-Labor-Messungen für Selen und den Entzündungsparameter hsCRP wurden für die drei Zeitpunkte statistisch verglichen. Ergebnis Die Literaturrecherche erbrachte zwei Wirkmechanismen, aufgrund derer Selen als Antioxidans und/oder essentieller Ko-Faktor von Enzymen im Serotoninstoffwechsel eine Rolle in der Behandlung depressiver Verstimmungen spielen kann. Bei der eigenen Studie beendeten von den 30 rekrutierten gesunden Teilnehmern 29 die Studie protokollgemäß. Die ermittelten Basis-Werte für den hsCRP-Inflammationsmarker waren niedrig und zeigten nach 6 Monaten der Einnahme eine Tendenz weiter abzufallen. Die Basiswerte für Selen lagen zu Studienbeginn mehrheitlich unter dem empfohlenen Referenzbereich. Die Basis-Selenwerte besserten sich bereits nach drei Monaten regelmäßiger Einnahme signifikant (p < 0,048). Besonders die intrazellulären Selenwerte wurden verhältnismäßig rasch und nachhaltig erhöht. Schlussfolgerungen Das Prüfpräparat weist eine gute Selen-Bioverfügbarkeit auf. Die regelmäßige Einnahme des Prüfpräparates bewirkte den Ausgleich niedriger Selenwerte zu Studienbeginn, und bewirkte die Tendenz zur Abnahme der ohnehin geringen Entzündungsparameter in gesunden Probanden. Beides, die beobachtete Selenzunahme aber auch die anti-inflammatorischen Wirkungen könnten die Stimmungslage positiv beeinflussen.
34

Vliv antioxidantů (selen, vitamin C a E) na spermatogenezi kanců

Svačinová, Lucie January 2015 (has links)
The purpose of this dissertation is the verification of antioxidants, the vitamin C, the vitamin E and selen influence on the spermgenesis of breeding boars. The ejaculate quality was evaluated with the use of qualitative and quantitative figures (the ejaculate volume, the motility, the sperm concentration and the number of abnormal sperms). The experiment was done at the boars' insemination station (ISK) in Velké Meziříčí. In the experimet, there were 12 boars of DUROC race involved. The boars were split into two groups. By the first boars experimental group (n=6) there were added into the feeding batch 350 mg of the vitamín C (ascorbe acid); 70 mg of the vitamín E (alfatocoferol) and 0,5 mg of selen (selenomethionin) per one kilogram of this special diet. The second group of boars was used as the checking group and the volume of the vitamin C, the vitamin E and the selen was not increased in their diet. The experiment was running for 90 days (June -- August). At the checking group the volume of their ejaculate was increasing untill the 60th day of the experiment, in the final stage it has significantly dropped, totally by -19%. By the experimental group, the volume of the ejaculate was constantly increasing trend and the total volume increase during the experiment duration was +32%. The sperm motility at the checking group has decreased from the original 69% down to 54%, while at the experimental group it has increased by approximatelly 1%. The sperm concentration check -- by the checking group it has increased by +6% and by the experimental group the sperm concentration has decreased by -24%. The number of abnormal sperms at the checking group has increased by +1% and by the experimental group the number of pathologic sperms has increased by +30%. Based on our results it is possible to say, that selen, the vitamin C and vitamin E do not have a provable effect on the boars ejaculate quality. But we must také into the consideration also the summer season, during which the experiment was provided. There were higher temperatures affecting the animals, which could have negative influence on the results.
35

Sledování obsahu selenu ve výživě vysokoškolských studentů

KRATOCHVÍLOVÁ, Zuzana January 2016 (has links)
The thesis is focused on monitoring the selenium intake of students from the University of South Bohemia in city Ceske Budejovice. A method of collecting values of the monitored nutrients was used for the experimental part and this data were collected by way of diets which individual respondents in the age group between 20-26 years recorded. The group of respondents consisted of twenty college students, ten women and ten men. During the monitored year every third week of the month in the period from January 19 to 25, 2015, from April 13 to 19, 2015 and from June 15 to 21, 2015 was always evaluated. In the monitored respondents the selenium incomes were on average at the level of 39 g per person per day and met the current level of saturation of the population of the Czech Republic, which is in the range between 25 to 40 g / day . In the evaluated group of respondents the average selenium intake reached 37 g for women and 42 g for men . This income is below the recommended daily allowance of selenium which is 55 g for women respectively 70 g Se / day for men. The found values correspond to moderately high deficiency of selenium intake. By evaluating diets of respondents there were also found not only inadequate intake of monitored selenium but also very unbalanced intake of macronutrients and energy. Improper diet composition and unbalanced nutrient intake may be one of the causes of selenium deficiency but probably deficiency of other micronutrients too.
36

Uplatnění vybraných forem selenu při pěstování máku setého (Papaver somniferum L.)

Tobek, Ladislav January 2016 (has links)
Selenium is an essential element for human organism. One of the possible ways to increase its quantity in food is a biofortification of crops. Czech Republic is the largest producer of poppy seeds in the world, it could be therefore viable to increase the nutritional value of selenium in this crop. The goal of this thesis was a recognition of suitability of selected forms of selenium for biofortification of seeds of opium poppy (Papaver somniferum). Aside from the distribution of selenium in the plant of poppy and its accumulation in the harvested seeds this study also investigates the effect of its soil and foliar application on the yield and weight of a thousand of seeds. The selenium was applied into the soil in 150, 300, and 600 g Se.ha-1 doses in the form of SeO32- and SeO42- in our one-year container experiment. The same forms of selenium were also applied foliarly in the 20 and 40 g Se.ha-1 doses in our one-year small-plot experiment. It is evident from the analysis of the distribution of selenium in the individual parts of the plant that selenite was accumulated primarily in the lower part of the plant (stalk and leafs) and only a maximum of 25.1% of the total was integrated in the capsule. Selenium, in the form of selenate, was contained in the capsule at a rate of 39.9 to 62.6% of the overall weight of the selenium contained in the whole plant. Soil and foliar application did not influence the yield and weight of a thousand of seeds. In both the container and field experiment the application of an increasing amount of selenium in the form of both selenite and selenate has significantly increased its presence in the harvested seed. Our results suggest that selenate is a better form of selenium for the biofortification of poppy.
37

Výživa u termických úrazů / Nutrition in thermic injury

Zemanová, Markéta January 2018 (has links)
Výživa u termických úrazů [Nutrition in Thermic Injury]. Bc. ZEMANOVÁ, Markéta, DiS. Praha, 2017. Počet stránek 84, 2. Diplomová práce (Mgr.) Univerzita Karlova, 1.lékařská fakulta Obor: Nutriční specialista Vedoucí práce MUDr. Robert Zajíček, Ph.d Abstract Aim of the thesis is summarizing current knowledge about clinical nutrition of patients with severe thermal injuries. Special emphasis is given to specifics of pediatric patients, who in many aspects react differently. The introduction focuses on history of burn medicine including nutrition, classification of burn injuries, prehospital care and role of individual members of the therapeutical multidisciplinary team logically centring on role of the dietitian. Extreme hypermetabolism, persisting a year or longer after the insult, influences nutritional recommendations including energy, macronutrients (protein, fats and carbohydrates) and micronutrients (minerals, vitamins and trace elements). Mode of administration is influenced as well. Specific facts are shown how these characteristics are reflected in daily dietetic therapy at the Clinic of Burn Medicine of the Prague Vinohrady Faculty Hospital (FNKV). In the investigative part we compare two groups of adult patients with extensive burn injuries. Inclusion criteria were age of 18-65 years, extent of...
38

Elektrochemické a matematické studium interakcí selenu s biologicky aktivními thioly / Electrochemical and mathematical study of interactions of selenite with biologically active thiols

Slavík, Jan January 2012 (has links)
Proteins with thiol groups interact with metal ions in the human body. They maintain their homeostasis, participate in cell signaling, protect the cell against the effects of toxic metals and detoxify them. This work is focused on proteins with thiol groups glutathione and metallothionein and their effects on selenium. The method of study is electrochemical.
39

Role selenu v pozdně hydrotermální fázi příbramského uranového rajónu / Role of the selenium in the late hydrothermal phase of the Příbram uranium region

Škácha, Pavel January 2015 (has links)
Příbram uranium and base-metal district is the most important vein uranium district in the Czech Republic. The main ore was represented by uraninite there and the occurrences of selenium mineralization are directly connected to it. The presence of selenides was not confirmed during the mining activities. Major development of the uranium-carbonate mineralization was found in the Bytíz deposit in the central part of the uranium district. All known occurrences of selenides have been found from this area only so far. Antimonselite, athabascaite, bellidoite (?), berzelianite, brodtkorbite, bukovite, clausthalite, dzharkenite, eskebornite, eucairite, giraudite, hakite, cadmoselite, klockmannite, naumannite, permingeatite, sabatierite, tiemannite and umangite, as well as the new unnamed selenium analogue of chalcostibite were newly identified from the dump material from the shafts No. 16 and 11A. The extremely Hg-rich hakite, which contains up to 30 wt.% of Hg, is the most remarkable mineral from the tetrahedrite group of minerals. The pertinence of the Hg-hakite was verified by means of the transmission electron microscopy. Uncommon recently formed supergene selenium association is represented by molybdomenite, munakataite and piretite. A large scale of associated minerals was found in association with...
40

Vliv selenu, zinku, vitamínu C a E na potlačení tepelného stresu u kanců

Půlpánová, Barbora January 2017 (has links)
The aim of the study was influence of the complex of two elements (zinc, selenium) and two vitamins (vit C, vit E) on the organism of pigs under heat stress. Twenty boars of the Duroc breed were included in the experiment. The boars were approximately the same age and weight, housed individually. They were divided into 2 groups. The control group (n = 6) was fed only to a basic feed mixture containing 0.02 mg Se; 21.5 mg Zn; 9.9 mg of vitamin E and 16.0 mg of vitamin C. In addition, 0.5 mg of selenomethionine, 70 mg of alpha-tocopherol, 70 mg of zinc oxide and 350 mg of ascorbic acid were added to the diet (n = 6). The experiment took place from June to September at the insemination station in Velké Meziříčí. The control group showed a slight increase in ejaculate volume (by 19 %), which is common in the summer months. At the same time, the sperm concentration was unstable, it increased by 15 % in August, but fell below the baseline by 3.5 % in September. Motility was around 69 % during the experiment. Statistically significant was an increase (by 15 %) of morphologically abnormal sperm in the ejaculate (P < 0.05). The experimental group had higher ejaculate from the beginning. However, the volume curve was almost identical to the experimental group. The sperm concentration increased by 23 % in the trial group after adding antioxidants. During the experiment the concentration only slightly decreased. Motility in the experimental group averaged 70 % and did not change significantly during the experiment. Even in the control group there was a statistically significant increase in morphologically abnormal sperm (by 12.3 %), (P <0.05). From the results it can be concluded that the increased amount of selected antioxidants did not have a demonstrable effect on the improvement of the ejaculate quality, but it can be assumed that this quantity has ensured the stability of the seed parameters.

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