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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.
1

Využití a omezení metod laserové ablace ICP-MS v geovědních disciplínách / Use and limitations of laser ablation ICP-MS in geoscience applications

Míková, Jitka January 2011 (has links)
This dissertation contributes to applications of laser ablation plasma source mass spectrometry (LA ICP-MS) in Earth sciences. The primary goal of the thesis is to address some of the fundamental processes related to laser ablation of solid samples that result in decoupling of elements during laser ablation ICP-MS analysis. Better understanding of mechanisms that cause the elemental fractionation and matrix effects is necessary before the accuracy and precision of laser ablation ICP-MS analyses can be improved. The chemical and phase compositions of particles produced by laser ablation (266 nm Nd:YAG) of silicate NIST glasses and zircon were studied by SIMS and HR-TEM techniques with a particular focus on Pb/U fractionation. This is of great importance in geology as the Pb/U elemental fractionation hampered the precision and accuracy of the measured accessory mineral ages. The data suggest that chemical composition and mineralogy of particles produced at the ablation site during laser ablation differs from the original sample and varies with their size. This can result in elemental fractionation (non-stochiometric sampling) in material delivered to the ICP-MS for quantitative analysis. Evidence of the element fractionation is preserved in chemically zoned ejecta deposited around the ablation pit....
2

Využití radiofrekvenční ablace v léčbě inoperabilních jaterních tumorů / Radiofrequency ablation in the treatment for inoperable tumours of the liver

Skalický, Tomáš January 2006 (has links)
MUDr. SKALICKÝ, Tomáš Five year period of experimental and clinical experience with radiofrequency ablation of liver tumors is described. RFA considerably extends the survival of patients with non-resectable liver metastases. The method has minimal complications and both mortality and morbidity are low.
3

Využití radiofrekvenční ablace v léčbě inoperabilních jaterních tumorů / Radiofrequency ablation in the treatment for inoperable tumours of the liver

Skalický, Tomáš January 2006 (has links)
MUDr. SKALICKÝ, Tomáš Five year period of experimental and clinical experience with radiofrequency ablation of liver tumors is described. RFA considerably extends the survival of patients with non-resectable liver metastases. The method has minimal complications and both mortality and morbidity are low.
4

Kvalita života u pacienta po katétrové ablaci / Quality of life in patiens after catheter ablation

KOCMICHOVÁ, Jana January 2014 (has links)
Theoretical Foundations Catheter ablation is an intervention focused on targeted removal of or damage to an area that causes arrhythmias. This intervention began to be performed at the turn of the 1980s and 1990s because it had been found that treatment with antiarrhythmic drugs was expensive and the drugs had to be taken throughout patients' lives. Thanks to its high success rate and low risk of complications, it has been used in the treatment of supraventricular tachyarrhythmias. At present, the success rate is around 75 %, and the intervention sometimes needs to be repeated to achieve its desired effect. Objectives of the thesis The first objective was to find out whether patients with a history of catheter ablation changed their personal and professional lives. The second objective was to map out which areas of the patients' live were affected most by the catheter ablation treatment. The third objective was to find out about differences in the patients' lives before and after catheter ablation. Research questions V1: In what areas are the patients' lives limited most? V2: What changes have occurred in their lives after catheter ablation? Methodology The research part of the thesis was carried out using a qualitative survey conducted by means of semi-structured interviews with patients suffering from arrhythmias. The total of 9 respondents, 5 males and 4 females, were interviewed. The information obtained was processed using programme Atlas.ti. The results are presented as networks created in this programme. Results The research questions can be answered using the data obtained from the respondents suffering from arrhythmias. The first research question was aimed at finding out in what areas the patients' lives were limited most. It was found out, through the semi-structured interviews, that the most limited area was personal life, in which arrhythmia caused most difficulties to the respondents during sports activities. Because of their health problems, most of the respondents limited their sports activities or abandoned them altogether in favour of their health. Other problems are caused during physical strain and under physical load. That was also the thing that the addressed respondents preferred to avoid. The respondents are also limited in the performance of their work, when the main cause of their problems is psychological stress, mental stress resulting in arrhythmia symptoms in the respective respondents. The second research question examined what changes occurred in their lives after catheter ablation. The changes that occurred related to the care of the family and the household in which they are able to engage in multiple activities. The respondents were able to pay more attention to their families by whom they are encouraged in the treatment. There was an overall improvement in their health, enabling better integration into everyday life. The most frequently mentioned area of changes was sport. During the period after catheter ablation, the respondents began to return gradually to their hobbies. Conclusion The thesis describes the restrictions that arrhythmia caused to the respondents and also the changes that have occurred in the individual respondents after catheter ablation treatment. The results can be used in practice in the education of patients who wait for the catheter ablation treatment and in subsequent measures using the prepared mind maps.
5

Charakterizace a fokusace svazku kapilárního XUV laseru pro účely depozice tenkých vrstev / Characterization and focusing of capillary-discharge XUV-laser beam for purposes of thin-film deposition

Pira, Peter January 2018 (has links)
Title: Characterization and focusing of capillary-discharge XUV-laser beam for purposes of thin-film deposition Author: Peter Pira Department: Department of Surface and Plasma Science Supervisor: doc. RNDr. Jan Wild, CSc., Department of Surface and Plasma Science Abstract: The paper deals with the first results of the interaction of a desk-top high repetition rate XUV laser (wavelength of 46.9 nm) radiation with materials suitable for optoelectronics, in particular the ionic crystals CsI, LiF, etc. Using surface physics methods (AFM, DIC Normanski microscopy) pulse laser imprints were investigated. Based on the results obtained, general information on the nature of ablation and desorption was obtained, which were compared with the results of the XUV-ABLATOR modified code modeling. Plasma arising from ablation was examined by a modified Langmuir probe system. The main result is the pulse laser deposition of thin films of Bi and CsI. Keywords: ablation, Pulsed Laser Deposition, XUV laser
6

Možnosti použití laserové ablace ICP-MS při analýze opálů / Application of the laser ablation ICP-MS in the analysis of gem opals

Čimová, Nikoleta January 2014 (has links)
15 samples of gem opals were analyzed by laser ablation inductively coupled plasma mass spectrometry (LA ICP-MS) and inductively coupled plasma mass spectrometry (ICP-MS). For this study were selected the most representative samples from Slovakia, Australia, Peru, Ethiopia, Mexico, USA and the Czech Republic. These samples were obtained from private collections. The study focuses on the geochemical relationships between various forms of opal originating from igneous and sedimentary environments based on the results from LA ICP-MS and ICP-MS. The major and trace element compositions are unique for each studied opal locality and important for understanding numerous aspects of opal formation. Major element analysis shows that opals are essentially pure SiO2 (77 - 92 wt. %). Al, Fe, Ca, K, Na and Mg are the main elemental impurities. The concentrations of the trace elements vary strongly depending on the opal locality. Differences were found, e.g., in the concentrations of REE and some refractory elements, which might be indicative for determining the provenance of opals. Many studies have been published explaining the origin of luminescence, microstructures and the thermal properties of opals. However, there are very few comprehensive studies comparing gem opals from the most important historical and...
7

Využití kontrastní ultrasonografie ke sledování efektu léčby jaterních nádorů radiofrekvenčních ablací / Use the Contrast-Enhanced Ultrasoun in the Morning of the Effect of Liver Tumors Treatment by Radiofrequency ablation

Korčáková, Eva January 2019 (has links)
Use the contrast-enhanced ultrasound in the monitoring of the effect of liver tumors treatment by radiofrequency ablation. Summary High quality imaging is crucial for the treatment of liver tumors by the percutaneous radiofrequency ablation. Imaging methods are used for planning, navigation of the intervention and monitoring after treatment. An early detection of residual tumor tissue or recurrence affect significantly the quality of life and life expectancy of the patients. Contrast enhanced ultrasound (CEUS) seems to be a suitable method for monitoring the locoregional treatment mainly because zero radiation impact on patient and allows the highly accurate real-time assessment of vascularization. The aim of my work was to verify the ability of CEUS to detect residual tumor tissue or tumor recurrence in the field of changes after radiofrequency ablation. We evaluated the group of 73 patients, who were treated by radiofrequency ablation (RFA) for liver cancer. CEUS reached in our group the overal sensitivity 77.27 %, and in the group of colorectal cancer metastases 83.33 %. We compared CEUS with results of computed tomography (CT), which is the most commonly used method for monitoring the treatment. CEUS and CT results are similar. Based on this study, the CEUS appears to be a suitable method for monitoring...
8

Simulace elektroporačního děje při terapii okluze stentu / Simulation of electroporation process in stent oclussion therapy

Hemzal, Martin January 2021 (has links)
This masteral thesis describes phenomenon of electroporation and it’s use to deal with occluded self-expandable metalic stent. Thesis briefly summarizes theory of electroporation, currently used medical treatments of occluded stents. The next part of the thesis is dedicated to current state of mathematical simulations of electroporation. The core of the thesis are simulations of electroporation effects on tissue of occluded metal stents.
9

Zesílení signálu laserem buzeného plazmatu využitím nanočástic / Enhancement of laser-induced plasma signal using nanoparticles

Salajková, Zita January 2021 (has links)
Analytické metody LIBS a LA-IPC-MS založené na Laserové Ablaci (LA) nabízejí možnost rychlé chemické analýzy přímo z povrchu vzorku. Nedávno bylo ukázáno, že interakce světla s nanočásticemi může být využita pro zlepšení analytických schopností těchto metod. Při interakci nanočástic s laserovým paprskem dochází k zesílení elektromagnetického pole v jejich blízkém okolí. Pokud jsou nanočástice přítomny na povrchu vzorku analyzovaném některou z metod založenou na LA, zesílené pole vytvořené interakcí laseru s částicemi může pozměnit průběh LA, a tak ovlivnit vlastnosti laserem indukovaného plazmatu. Bylo zjištěno, že použití nanočástic může snížit práh ablace, zesílit signál a změnit vlastnosti aerosolu. Nanočásticemi zesílená LIBS (NELIBS) našla své využití tam, kde použití konvenční LIBS je problematické, a to například při analýze vzorků, kdy je jejich poškození nežádoucí nebo u analýzy roztoků mikrolitrových objemů s limity detekce nižšími než ppm. Tato dizertační práce předkládá podrobný popis jevů doprovázejících nanočásticemi zesílenou LA, založený na rozsáhlé experimentální práci a fyzikální teorii. Na základě pochopení základních principů byly vyvinuty dvě nové aplikace. Nejprve, byla NELIBS použita pro detekci kovových iontů v řetězcích amyloidů, pokročilého bio-materiálu určeného pro čištění vody. Dále byla NELIBS využita jako nová metoda pro monitorování proteinové korony vytvořené kolem nanočástic, čímž tato aplikace rozšířila klasické použití NELIBS za hranice prvkové analýzy.
10

Expertní systém pro vyhodnocení typu arytmie při katétrové radiofrekvenční ablaci srdečních arytmií / Expert System for Assessing the Type of Arrhythmia during Catheter Radiofrequency Ablation of Cardiac Arrhythmias

Šromová, Michaela January 2013 (has links)
The theoretical part of the thesis contains a brief description of the anatomy and electrophysiology of the heart, as well as both, surface and intracardiac electrocardiograms. The thesis also describes the different types of cardiac tachycardias, their differential diagnosis and what is known as The Expert System. The practical section of the thesis notes and outlines the tree diagrams, and additionally describes various software solutions of The Expert System. Further, the thesis includes the classification of the heart rhythm, using The Expert System method with three typical tachycardia cases, and including a list of questions asked by The Expert System to the user. Answers to all questions asked are being assessed in the text, as well as illustrated in submitted examples of intracardiac ECG recordings. The Expert System has been verified during a series of catheterization procedures on 26 patients (where the evaluated cardiac rhythm was 34). The classication of the type of heart rhythm (per The Expert System) when comparing the results with the doctors coincided in 100 % of tested cases.

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