National Repository of Grey Literature 79 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
Liver cells regeneration in mammals
Ťažký, Timotej ; Tlapáková, Tereza (advisor) ; Onhajzer, Jakub (referee)
Liver cell regeneration is an important biological process that allows mammals to maintain liver function while recovering from liver damage. Liver cell proliferation serves as the primary mode of liver regeneration, which in hepatocytes is activated by the transition from the G0 to G1 phase of the cell cycle. Proliferation is also promoted by non-parenchymal liver cells among which include Ito cells, Kupffer cells, and endothelial cells of hepatic sinusoids. In a comprehensive analysis of key signaling pathways, it was clearly demonstrated that the Wnt/β catenin, Notch, Hippo, NF-κB, and Hedgehog signaling pathways play a key role in the regulation of liver cell proliferation and differentiation during regeneration. The regenerative potential of the liver is influenced by various factors such as age, extent of damage and health conditions. Additionally, the remarkable regenerative capacity of the liver has clinical implications in the context of liver transplantation, partial hepatectomy and the treatment of liver diseases such as cirrhosis, hepatitis and hepatocellular or cholangiocellular carcinoma. Modulation of key signaling pathways and identification of novel molecular targets can improve the clinical outcomes of patients with liver diseases or even accelerate the entire process of liver...
Evolution of litter size in hystricomorph rodents
Cingelová, Alexandra ; Dušek, Adam (advisor) ; Špoutil, František (referee)
The suborder Hystricomorpha is an ideal model group for the study of rodent life-history evolution due to its wide distribution, great diversity of inhabited ecosystems and social systems. By tracking several factors, it was possible to determine the key factors that influenced litter size during evolution. The data set contained 75 of the total 292 species of the suborder. The average litter size, female and male body size, level of sexual dimorphism, level of sociality, type of reproductive system, level of parental care, presence of multipaternity, type of habitat and food were assigned to each species based on the information obtained from the available literature. The analysis included a statistical part calculated using general linear mixed models, and a phylogenetic part including parsimonious mapping of characters onto the phylogenetic tree and linear regression using phylogenetic independent contrasts. Social factors like degree of sociality, sexual dimorphism and reproductive system significantly influenced litter size at birth. Multipaternity also had an influence, but less than the first three factors. Ecological factors, food and environment, had no effects unless they were combined with the effect of family. It is therefore possible to assume that ecological factors have influenced...
Laboratorní test disasortativního párování u hraboše polního - literární rešerše
BÍLKOVÁ, Pavlína
Petrásková P. (2019): Laboratorní test disasortativního párování u hraboše polního - literární rešerše [Laboratory test of disassortative pairing in the common vole - literature search. Bc. Thesis in Czech]-49 pp. , Faculty of Sciences, University of South Bohemia, České Budějovice, Czech Republic. The aim of this work is to use the literature research to map current knowledge about the effect of odour preference on reproductive success in mammals focusing on voles. As assortative pairing is referred to each form of non-random pairing. Most of the time is meant a situation in which individuals who have similar phenotypes pair more often. The opposite is the situation where individuals with different phenotypes pair more often. This is sometimes referred to as negative assortative or disassortative pairing. In particular, this study deals with non-random pairing among to body odour . These are mainly linked to genes for the major histocompatibility complex (MHC) in animals, which play a key role in the immune system. MHC gene products found in various body secretions form the specific odour of each individual. In the research part were searched question for following questions: How is the breeding partner chosen? Is Assortative or Disassortative Pairing More Frequent? What information does body odour convey? What channels is the odour information transmitted and received? How is odour preference testing solved in laboratory conditions? In the practical part, a plan of the experiment is presented in which T-labyrinth will play the main role in determining the odour preference. Under laboratory conditions, voles will have plenty of time to complete the process
Typology and teeth determination of selected mammalian species
Černá, Adéla ; Říhová, Pavla (advisor) ; Pyszko, Martin (referee)
In this bachelor's thesis I am dealing with mammalian teeth. I have focused mainly on the teeth of certain species that are endangered and for which significant levels of illegal trade have been recorded. In selecting the species I focus on, I base my thesis on the analysis of data from the EU-TWIX and CITES Trade Database, which is compiled at the Environmental Forensic Sciences at the Faculty of Science, Charles University. The most endangered species traded include felines, canids and ursids. In this thesis, I mention how teeth can be identified, what an ideal tooth should look like, I describe what a tooth is made of, why teeth are traded at all, what they are used for, and how individual teeth can be confused with other mammal species. I also mention the Convention on International Trade in Endangered Species CITES. For this research I have largely used articles from abroad, available on the Web of science. Key words: teeth, mammals, determination
Molecular basis of the sperm selection in the mammalian female reproductive tract
Šrámková, Adéla ; Krylov, Vladimír (advisor) ; Postlerová, Pavla (referee)
Internal fertilization is typical for all mammals. The male transfers sperm cells into the female reproductive tract, where usually one of them reach the oocyte and fertilize it. The female reproductive tract must be adapted to provide a suitable environment for the sperm cells to survive until fertilization. On the other hand, it must also be able to select developmentally competent sperm cells and prevent others to get into the close contact with the oocyte. Physical and molecular mutual communication of sperm cells with the female reproductive tract is ensured by sperm surface molecules and the receptors of the female epithelia lining. It appears that these interactions are required for key transformations, both on the sperm surface and in the cells of the female reproductive tract, where gene expression is affected. As a result of these changes, the most suitable sperm cell with all the required characteristics is allowed to fertilize the matured oocyte.
Magnetic orientation in mammals
Tejmlová, Kristýna ; Němec, Pavel (advisor) ; Vácha, Martin (referee)
Earth's magnetic field can provide animal with both directional and positional information. The ability to perceive and utilize information extracted from the geomagnetic field is called magnetoreception. Magnetoreception mechanisms remain largely unknown. Three main hypotheses are currently supported by experimental evidence. The light-independent mechanisms are based either on electromagnetic induction or on biogenic magnetite. The light-dependent mechanism is based on specific chemical reaction between radical pairs. Perception of the geomagnetic field facilitates both long- and short-distance orientation of animals. Some animals exhibit the magnetic alignment, i.e., spontaneuos preference for a certain geomagnetic direction. Another manifestation of magnetoreception is magnetic compass (polarity- or inclination-based, depending on species), which enable an animal to determine the azimuth, i.e., the angle between the direction of motion and geomagnetic field vector. Magnetic map sense enable an animal to determine its position and direction to the goal destination, most likely utilizing the inclination and the intensity of the geomagnetic field as navigational cues. Magnetic orientation of mammals seems to be a widespread phenomenon. Light- independend, polarity compass has been reported in...
Bird and Mammal Taxidermy
Tuzová, Lucie ; Řezníček, Jan (advisor) ; Štěpán, Jiří (referee)
This thesis deals with the preparation of dermoplastic materials of birds and mammals. They are described in detail specific methods of preparation from the collection of material to its final treatment. The first section summarizes the theoretical knowledge concerning preparation of dermoplastic models and osteological material. The second part is dedicated to knowledge survey of high school and primary school students concerning recognition of birds and mammals dermoplastic models. The results are processed by descriptive statistics. Keywords: taxidermy, dermoplastic models and osteological material, skulls, teeth, birds, mammals.

National Repository of Grey Literature : 79 records found   1 - 10nextend  jump to record:
Interested in being notified about new results for this query?
Subscribe to the RSS feed.