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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.
551

Alkaloidy rostlin čeledi Amaryllidaceae a jejich biologická aktivita 1. / Alkaloids of the family Amaryllidaceae and their biological activity 1.

Mišáková, Kamila January 2014 (has links)
Mišáková K: Alkaloids of the Amaryllidaceae family and their biological activity 1. Diploma thesis, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové, 2014, 63 p. The aim of the diploma thesis was a preparation of alkaloidal extract from Nerine Bowdenii to izolation of 2 pure alkaloids by column and thin layer chromatography. Subsequently these two alkaloids were subjected to structural MS and NMR analysis and tested for biological activity against human cholinesterases (HuAChE and HuBuChE) and for antioxidant and cytotoxic activity. Isolated substances were identified as ambelline and undulatine alkaloids, which have been already described previously in this plant. In the test for determining cholinesterase inhibitory activity of ambelline and undulatine the following values were measured; for ambelline: IC50, HuAChE = 169 ± 7 μM a IC50, HuBuChE = 985 ± 25 μM, for undulatine: IC50, HuAChE = 23,52 ± 1,19 μM a IC50, HuBuChE > 1000 μM. Galanthamin (IC50, HuAChE = 1,71 ± 0,007 μM, IC50, HuBuChE = 42,30± 1,30 μM), huperzin A (IC50, HuAChE = 0,033 ± 0,001 μM, IC50, HuBuChE > 1000 μM) and eserin (IC50, HuAChE = 0,063 ± 0,001 μM, IC50, HuBuChE = 0,130 ± 0,004 μM) were used like a positive controls. In the test for...
552

Každodenní život a problematika sociální izolace seniorů v městském a venkovském prostředí / Everyday life and social isolation of elderly people in urban and rural environments

Petrišče, Ondřej January 2015 (has links)
EVERYDAY LIFE AND SOCIAL ISOLATION OF ELDERLY PEOPLE IN URBAN AND RURAL ENVIRONMENTS THE ABSTRACT: My presented diploma thesis includes two concepts. The first one describes the quality of life and residential environments; the second concerns social isolation. Both of these examine a different view on the quality of life within the senior generation because the daily life of the older generation is influenced by the intensity and frequency of sociable relations together with the quality of residential environment in which they live. In the study I chose two different types of environments - an urban environment of Plzeň, a borough of Doubravka and a rural environment of a small village - Pasečnice. In the work, I observed the strengths and weaknesses of these environments in a group of people, who were interviewed. The research was made with semi-structural interview and analyzes the disposition of social isolation and the personal feeling about each residential environment. Diploma thesis concentrates on the main factors in senior's daily lives such as social relations, housing, basic service facilities, transportation availability, free time, and safety in the mentioned area of living. Key words: social isolation, quality of residential environments, seniors, city, country, civic facilities
553

Biologická aktivita obsahových látek rostlin XXVII. Alkaloidy Fumaria officinalis L. a jejich účinek na acetylcholinesterasu a butyrylcholinesterasu. / Biological activity of plants metabolites. XXVII. Alkaloids of Fumaria officinalis L. and their effect on acetylcholinesterase and butyrylcholinesterase.

Hulcová, Daniela January 2014 (has links)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany and Ecology Candidate: Daniela Hulcová Consultant: Prof. RNDr. Lubomír Opletal, CSc. Title of Diploma Thesis: Biological aktivity of plants metabolites. XXVII. Alkaloids of Fumaria officinalis L. and their effect on acetylcholinesterase and butyrylcholinesterase The summary ethanolic and diethylether extract were prepared from the herbs of a plant Fumaria officinalis L. We have obtained 201 fractions from this extract by column chromatography on the neutral Al2O3 (aluminium oxide). Joined fraction 68-76 were processed by thin layer chromatography, and 3 substances were obtained in pure state: DH-1, DH-2, DH-3. These 3 compounds were identified as protopine, (+)-fumariline and N- methylcorydaldine by the comparison with the literature and results of MS and NMR. These alkaloids were tested for the inhibitory activity against human erythrocytic acetylcholinesterase and plasmatic butyrylcholinesterase by Ellman`s method. The isolated alkaloids did not show any significant inhibitory activity (IC50, µM) compared with the standard galanthamine (IC50, µM; AChE 1,710 ± 0,065, BuChE 42,30 ± 1,30): protopin: AChE: 345,42 ± 31,12, BuChE: 239,66 ± 20,89, (+)-fumarilin: AChE: 2939,2 ± 309,41, BuChE: 330,62 ±...
554

Charakterizace transkripčního aparátu lineárních plasmidů kvasinky Kluyveromyces lactis / Characterization of transcription apparatus encoded by the linear plasmids of the yeast Kluyveromyces lactis

Sýkora, Michal January 2013 (has links)
Transcription is an essential step in the expression of genetic information. This process depends on protein complex of multisubunit RNA polymerases that are exceptionally conserved among all cellular organisms. These enzymes together with eukaryotic RNA-dependent RNA polymerases involved in gene silencing form a monophyletic protein family whose members contain two double-ψ β-barrel structural motifs in their active center. This family also includes a group of mainly in silico predicted non-canonical DNA-dependent RNA polymerases which differ from multisubunit RNA polymerases in reduced composition. Putative non-canonical RNA polymerase consisting of two subunits is also encoded by cytoplasmic linear plasmids of the yeast Kluyveromyces lactis and highly likely transcribes genes of these plasmids. Characterization of a unique transcription machinery of Kluyveromyces lactis plasmids with major emphasis on non-canonical RNA polymerase has become the aim of this work. Bioinformatic analysis in silico was used to examine the evidence leading to an assumption of existence of specific RNA polymerase. Subsequent genetic and biochemical methods were used for: 1) production of putative RNA polymerase subunits in several expression systems; 2) testing interaction between several components of transcription...
555

Early life stress and its association with epigenetics and immune system response

Maj, El sharif January 2017 (has links)
Stress can induce prolonged deleterious effects on many characteristics in chickens (Gallus gallus). Particular interest has been paid to early life stress. Social isolation as an early life stressor results in increased plasma corticosterone levels. Moreover, it induces behavioural and physiological changes as well as gene expression modifications in the hypothalamus. In the first part of my study, I aim to inquire into social isolation impacts on the short and long-term. Short and long-term effects were assessed by immune system, behaviour and weight. 82 male chickens were assigned to three groups (stress, control and enrichment). The stress group was exposed to social isolation, the enrichment group was provided with enrichment substrates while the control group was left untreated. According to my knowledge, this is the first study that investigates the effects of social isolation on the interuleikn-6 levels as an indicator of immune system response. My findings suggest that social isolation induces short and long-term effects on immune response as well as on body weight. In the second part of my study, I aim to develop a method investigating effects of early stress on DNA methylation in blood and sperm. For this purpose, two methods GBS (Genotyping by sequencing) and MeDIP (Methylated DNA immuneprecipitation) were f using pooled DNA from all individuals for the first time. Moreover, I developed a protocol for extracting sperm DNA from frozen testis. Combining both methods has many advantages, such as cost effectiveness and the ability to evaluate epigenetic signatures in large number of individuals
556

Biologická aktivita sekundárních metabolitů rostlin IV. Alkaloidy Vinca minor L. / Biological aktivity of secondary plants metabolites IV. Alkaloids of Vinca minor L.

Vítovcová, Aneta January 2016 (has links)
Vítovcová, A.: Biological activity of secondary plants metabolites IV. Alkaloids of Vinca minor L. Diploma thesis, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové 2016. Extract of Vinca minor L. was separated to fractions in column chromatography. Flash chromatography, preparative TLC and crystalisation led to isolation of two alkaloids from fraction number two and number five. Alkaloids were identified by GC/MS as (+)-vincaminorine and vincorine. These alkaloids were tested for their inhibition activity towards cholinesterase (AChE and BuChe). Obtained activities IC50 were compared with standards (galanthamine, huperzine A). The most interesting activity against galanthamine (AChE 1,710 ± 0,065 µM, BuChE 42,30 ± 1,30 µM) and huperzine A (AChE 0,033 ± 0,001 µM, BuChE > 1000 µM) showed vincorine (AChE > 1000 µM, BuChE 9,75 ± 0,45 µM). His activity toward BuChE is higher than the activity of both standards. Inhibition activities of (+)-vincaminorine (AChE 746,5 ± 84,13 µM, BuChE 684,32 ± 70,66 µM) are negligible. Key words: Alzheimerʼs disease, cholinesterase, Apocynaceae, Vinca minor L., indole alkaloids
557

Biologická aktivita sekundárních metabolitů rostlin VI. Alkaloidy Vinca minor L. / Biological aktivity of secondary plants metabolites VI. Alkaloids of Vinca minor L.

Kučerová, Jana January 2016 (has links)
1 ABSTRACT Kučerová J.: Biological activity of secondary plants metabolites VI. Alkaloids of Vinca minor L. Diploma thesis, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of pharmaceutical botany and ecology, Hradec Králové 2016, 67 pages. Isolation of alkaloids was done from extract of Vinca minor, family Apocynaceae. Individual substances obtained were examined for their ability to inhibit human acetylcholinesterase and butyrylcholinesterase. The basic extract was after an initial extraction with 95% ethanol pre-purified by extraction with chloroform. This chloroform extract was divided further by column chromatography on a total of 531 fractions. The fractions obtained were, based on the similarities identified by thin layer chromatography, interconnected in a final number of 17 fractions. The mobile phase for column chromatography were mixtures of chloroform and medical gasoline, chloroform and ethanol, and ethanol itself. For further testing were used fractions number 2 and 5. From the fraction 2 was by preparative thin layer chromatography and subsequent crystallization isolated substance number 1. After analysis of this substance by GC/MS was found that it is a (+) - vincaminorein. Further was examined it's biological activity towards cholinesterases, which found a...
558

The relationship between social isolation, social support, and mental health

Harasemiw, Oksana 15 April 2016 (has links)
This study explored how the structural aspects of a social network (that is, number of social ties, frequency of contact, as well as social participation), along with the functional aspect (social support), relate to mental health. Using data from the baseline questionnaire for the tracking cohort of participants in the Canadian Longitudinal Study on Aging, community-dwelling older adults aged 65-85 years old were studied. Cluster analysis was used to group individuals into different clusters, based on their structural social network characteristics. Six clusters were found, ranging from most socially integrated, to moderately integrated, to socially isolated. Univariate analyses indicated that as level of social integration decreased, individuals fared increasingly worse in terms of their mental health outcomes. Furthermore, a series of mediation analyses showed that social support mediated the relationship between social integration level, and mental health, an effect that was strongest for the most socially isolated individuals. / May 2016
559

The Effects of Coursecasting in International Freshman Students' Perceptions of Marginality and Isolation, Anxiety, and English Language Oral Proficiency and Comprehension

Fernandez, Alberto 01 January 2011 (has links)
The influx of international students attending American universities has put the U.S. at the forefront of international education, generating over $14.5 billion yearly. International students often face adjustment issues impacting their level of satisfaction with their experience. These involve oral language proficiency, as well as feelings of anxiety and isolation resulting from language deficiencies, which increase their feelings of marginality. Engaged learning, which is dependent on comprehension, is affected by the anxiety students bring to class. It is believed that coursecasts may alleviate anxiety, thus improving student engagement in learning. A pre-experimental research design investigates whether coursecasting mitigates feelings of marginalization and isolation, deficiencies in language comprehension and proficiency, and anxiety in international students. Research in the value of coursecasting has been anecdotal, and concrete evidence of its educational value is needed before its wide-spread adoption in educational settings (Elliot, King, & Scutter, 2009). Participants completed the Cultural Adjustment Difficulties Checklist (CADC) by Sodowsky and Lai (1997), the Foreign Language Classroom Anxiety Scale (FLCAS) by Horwitz, Horwitz, and Cope (1986), the Self-Reported Fluency of English Scale (SRFES) by Yeh and Inose (2003), and the Test of English as a Foreign Language (TOEFL), Listening portion. A pretest-posttest approach was chosen to evaluate the influence of podcasting within a naturalistic setting. The implications of the study were categorized into three areas. First, it provided insight into the barriers that negatively impact international student learning due to anxiety. Second, it identified methods of instruction, and issues that may have hindered international students from achieving at their highest level. Finally, it provided an opportunity to explore the educational effectiveness of a technology created for entertainment. Quantitative measures yielded no significance, so the null hypotheses were rejected. It was thought that these results were due to limited exposure to the coursecasting treatment. Their significance was further discussed by providing conclusions and implications. Recommendations for future research suggest replicating the study with a control group or administering the coursecasting treatment for a longer period of time. Suggestions for educators and educational institutions include requesting faculty and staff to identify specific ways to help this vulnerable population with their acculturation instead of waiting for them to ask for help. Although no significant impact could be established between available coursecasts and international students' perceptions of marginality and isolation, anxiety, and English language proficiency and comprehension, the findings regarding the analysis of the dependent variables seem to present interesting implications for education.
560

Macroeconomic Indicators of Working Class Voter Abstention in US Presidential Elections, 1948-2004

Kessing, Christopher 20 May 2011 (has links)
In this paper I explore the causal relationship between the strategic economic interdependence advanced by Western democracies after WWII and the "puzzle of participation" in US presidential elections. More specifically, I seek to illustrate first how economic convergence within the West and then the transition from Keynesian to monetarist policy rhetoric reflexively diminish the degree to which US working class voters can realistically petition their elected officials regarding the most salient matters of economic self-interest. My results indicate that from 1948-2004, the working public became more isolated from their most salient economic decisions, voted less often due to heretofore unexplored macroeconomic indicators.

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