• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 73
  • 18
  • 3
  • 2
  • 2
  • Tagged with
  • 100
  • 54
  • 22
  • 20
  • 12
  • 10
  • 9
  • 9
  • 7
  • 7
  • 6
  • 6
  • 6
  • 6
  • 6
  • 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.
71

Porovnání genetické variability geograficky vzdálených populací vybraných evropských mořských druhů hlaváčů / Comparison of the genetic variability of geographically distant populations of selected species of European marine gobies

Chalupecká, Katarína January 2018 (has links)
Gobies (Gobiidae, Actinopterygii) are small, predominantly cryptic, marine, brackish and freshwater fishes. They abundantly inhabit coastal waters, although their occurrence is far from being mapped due to their inconspicity, often hidden lifestyle and a lack of commercial use. Information about distribution of many species is therefore still rather poor. Many species are known only from a few locations scattered throughout the Mediterranean Sea and the Atlantic. This suggests that most species could actually have a relatively continuous distribution area. Comparing the genetic variability of geographically distant populations of the same species can help to detect whether there is some population subdivision and whether populations are genetically isolated from each other. The aim of my thesis was to compare genetic variability of the populations of eight goby species: Corcyrogobius liechtensteini, Gobius cruentatus, Gobius geniporus, Gobius incognitus, Chromogobius quadrivittatus, Chromogobius zebratus, Millerigobius macrocephalus and Zebrus zebrus within Mediterranean Sea and north-eastern Atlantic Ocean. Samples used in this work were collected from two Atlantic (Spain and Portugal) and seven Mediterranean localities (France, Sicily, Croatia, Montenegro, Greece, and Cyprus - northern and...
72

Korelace imunohistochemických a molekulárně biologických metod v diagnostice nádorů / Correlation of Immunohistochemistry and Molecular Biologic Methods in The Diagnosis of Tumors

Michal, Michael January 2018 (has links)
This thesis is a collection of commentaries on altogether 13 first-authored and 20 co- authored publications where morphology, immunohistochemistry (IHC) and molecular genetic methods were used to provide novel clues for arriving at an accurate diagnosis of tumors, as well as to propose novel approaches and refinement of classification of certain tumors. The presented manuscripts are the result of the postgraduate studies of MUDr. Michael Michal at the Charles University in Prague, Faculty of Medicine in Pilsen in the period between 2015-2018. The author focused the main part of his research, particularly his first-authored manuscripts, on soft tissue tumors but also largely participated in research activities focusing on other body systems. Over the course of his studies, four main areas of interests within the topic of soft tissue pathology emerged. The first is oriented on soft tissue tumors of presumed (but unconfirmed) fibroblastic lineage. First two publications regard two related low-grade sarcomas called Myxoinflammatory fibroblastic sarcoma (MIFS) and Pleomorphic hyalinizing angiectatic tumor (PHAT). In the first manuscript, a high-grade variant of the former is described. The latter publication is focused on the morphological and IHC similarities between both MIFS and PHAT. The third and...
73

Biologie, ekologie a charakteristiky invaze druhu Campylopus introflexus v České Republice / Biology, ecology and invasion characteristics of Campylopus introflexus in the Czech Republic

Mikulášková, Eva January 2012 (has links)
A B S T R A C T Ecological and economic impact of invasive plants to natural ecosystems is the subject of many studies; however, invasive bryophytes have been stud- ied only marginally. Campylopus introflexus (Hedw.) Brid. is one of the most strongly invasive bryophyte species in Europe. The species appears to be native in the Southern Hemisphere. In Europe, it was collected for the first time in the British Isles in 1941. The moss has expanded eastward and the first collection in the Czech Republic is dated to 1988. This thesis found that more than 70 localities were known known in the Czech Republic in 2006, and more than 100 localities became known by 2011. It has been further demonstrated that the Czech Republic was colonized repeatedly by generative spores and all populations have a unique genetic composition. Genetic variation of the populations is low, the genetic diver- sity of populations within the Czech Republic is not correlated with their geographic position or with any of the monitored environmental variables. At a fine scale within particular localities, the species disperses by vege- tative diaspores, while it uses generative spores for spreading over longer distances. In Central Europe, C. introflexus prefers open coniferous forests, especially plantations of either spruce or pine. It colonizes...
74

Proměny pojetí genu v první polovině 20. století / Changes of the gene concept in the first half of the 20th century

Hájková, Jana January 2013 (has links)
This dissertation shows various concepts of the term gene that have appeared since the birth of genetics in 1900 up to the first half of the 50s. It focuses especially on the 40s and the beginning of the 50s. Scientific papers from that period were the main source of information. The author tried to capture not only generally accepted notions about genes and genic action but also those that had not pushed through in those days, nevertheless, that had offered a non- standard point of view which could have later become inspirative for molecular genetics. The work documents searching for links between genes and enzymes or ideas of potential divisibility of the gene. The dissertation assigns a very important role to those phenomena that emphasized the significance of the gene order or the order of genic parts. In Goldschmidt's interpretation of pseudoallelism the author sees the thought that the essence of a gene is its position and considers this the beginnings of "digital" thinking about the gene. The dissertation pays attention to "analogue" thinking about the gene, as well. This thinking took account of molecular shaping and represented a blind alley for the early molecular genetics. The work confirms to a certain extent the Kuhnian vision of the development of scientific disciplines. It finds the...
75

Genetické příčiny medulárního karcinomu štítné žlázy a Hirschsprungovy choroby / Genetic causes of medullary thyroid carcinoma and Hirschsprung's disease

Václavíková, Eliška January 2015 (has links)
Genetic causes of medullary thyroid carcinoma and Hirschsprung's disease Abstract Medullary thyroid carcinoma (MTC) and Hirschsprung's disease (HSCR) are classified as simple neurocristopathies, i.e. diseases linked to neural crest-derived cells. MTC is derived from parafollicular cells of the thyroid and HSCR is characterized by absence of enteric ganglia in the gastrointestinal tract. The RET proto-oncogene is only expressed in neural crest-derived cells, including parafollicular cells and enteric neurons. The RET encodes a transmembrane tyrosinekinase receptor that plays an important role during proliferation, differentiation and cell survival, and activates many signaling pathways. If the strictly regulated activation fails, e.g. due to mutations in the specific gene locations, the RET becomes a highly effective oncogene. Activating germline mutations in the RET proto- oncogene lead to hereditary forms of MTC, whereas sporadic forms of MTC are caused by somatic mutations in the tumor tissue. On the contrary, inactivating mutations induce migration failure of ganglion cell precursors during the development of enteric nervous system and result in the development of HSCR. In rare cases, the coexistence of both diseases is caused by mutations with a dual gain-of-function and loss-of-function character....
76

Hledání nových biomarkerů neplodnosti mužů pomocí transkriptomu spermií / Using Sperm Transcriptome in Search for Novel Biomarkers of Male Infertility

Semyakina, Anastasiya January 2019 (has links)
Currently infertility affects 10 to 15 percent of couples. In nearly 50% of all cases male factor contributes to infertility of the couple. Majority of causes of male infertility remains unexplained. For this reason, finding simple and clinically useful tools for improving male infertility diagnostics can be important at present. Based on the analysis of sperm transcriptome, in this diploma thesis we aimed to find genes that show differential expression between normal and pathological sperm, this could provide information about molecular basis of male infertility, moreover, expression profile of such genes in sperm could be employed for noninvasive diagnosis of male infertility. This study was conducted by using 67 sperm samples, including 16 control sperm samples from fertile men. The samples of infertile patients were divided into 3 groups according to morphology and motility using results of standard sperm evaluation according to WHO. First group included 20 patients diagnosed with astenoteratozoospermia (low sperm motility and abnormal morphology), second group was 15 patients diagnosed with asthenozoospermia (normal morphology and low sperm motility), the third group comprised 16 samples from infertile patients with normal spermiogram. 16 control samples were from fertile men (conception of...
77

Hledání nových biomarkerů neplodnosti mužů pomocí transkriptomu spermií / Using Sperm Transcriptome in Search for Novel Biomarkers of Male Infertility

Semyakina, Anastasiya January 2018 (has links)
Currently infertility affects 10 to 15 percent of couples. In nearly 50% of all cases male factor contributes to infertility of the couple. Majority of causes of male infertility remains unexplained. For this reason, finding simple and clinically usefµl tools for improving male infertility diagnostics can be important at present. Based on the analysis of sperm transcriptome, in this diploma thesis we aimed to find genes that show differential expression between normal and pathological sperm, this could provide information about molecular basis of male infertility, moreover, expression profile of such genes in sperm could be employed for noninvasive diagnosis of male infertility. This study was conducted by using 67 sperm samples, including 16 control sperm samples from fertile men. The samples of infertile patients were divided into 3 groups according to morphology and motility using results of standard sperm evaluation according to WHO. First group included 20 patients diagnosed with astenoteratozoospermia (low sperm motility and abnormal morphology), second group was 15 patients diagnosed with asthenozoospermia (normal morphology and low sperm motility), the third group comprised 16 samples from infertile patients with normal spermiogram. 16 control samples were from fertile men (conception of...
78

Genetická determinace diabetu druhého typu, konfirmační studie na české populaci. / Genetic determination of T2DM, confirmatory study on Czech population.

Dlouhá, Lucie January 2017 (has links)
No description available.
79

Biotechnologie jako politický systém / Biotechnology as political problem

Sobotková, Lenka January 2008 (has links)
Thesis is concentrated on two biotechnologies: biofuels and genetically modified crops. Defines technical and economical characteristics, lists international agreements and czech and european legislation regarding both biotechnologies. Introduces opinions and analyses positions of selected political subjects as UNO, WTO, OECD, EU, catholic church and main czech political parties.
80

Ochranářská genetika vlka obecného ve střední Evropě / Conservation genetics of the grey wolf in Central Europe

Valentová, Kamila Anna January 2021 (has links)
Conservation genetics of the grey wolf in Czech Republic and adjacent regions is studied in the present thesis. Analyses of twenty-one microsatellite loci, one sex-determining amelogenin gene and mitochodrial control region were used to verify species determination, identify individuals and estimate relationships between them, analyse population structure and estimate demographic trends based on samples collected between 2014 and 2021. Genetic detection of red fox and dog samples incorrectly assigned to wolves illustrates the hurdles of field monitoring of grey wolf. Direct evidence for the occurrence of F1 hybrids was not found. Wolves from Bohemia showed lower values of allelic richness in comparison to the ones from Western Carpathians, probably as a consequence of recent expansion. Geographic distances between detection sites of identical individuals were relatively small or moderate in this study, suggesting regular movements of animals within their home ranges. Only two long-distance dispersal events exceeding 300 km were detected. Results of parental analysis provided evidence of pack distribution within the studied area. Most relationships were detected between wolves in the northern region of Czech Republic where the first recolonizing wolf pack in 2014 was registered. Within the studied...

Page generated in 0.053 seconds