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1342. Stopy retrovirů v lidském genomu
- Creator:
- Famfulíková, Mirka and Jan Pačes
- Format:
- bez média and svazek
- Type:
- article, text, články, journal articles, model:article, and TEXT
- Subject:
- Biologické vědy, biologie, retroviry, RNA viry, lidský genom, genetická transkripce, biology, retroviruses, RNA viruses, human genome, genetic transcription, endogenní retrovirové elementy, human endogenous retroviruses, HERV, 2, and 57/59
- Language:
- Czech
- Description:
- Retroviry jsou RNA viry, které se replikují v hostitelské buňce. Využívají enzymu reverzní transkriptázy, která přepisuje jejich RNA do DNA. Tato DNA je pak enzymem integrázou začleňována do hostitelského genomu. Pokud dojde k integraci retroviru v germinální linii, může se tento retrovirus stát součástí lidského genomu. V lidském genomu tyto retrovirové elementy (Human Endogenous Retroviruses = HERVs) tvoří až 8 % DNA. Donedávna se vědci domnívali, že HERVy jsou neaktivní, tzn. neinfikují další buňky. Během evoluce byly mnohokrát mutovány a pozbyly schopnosti genové exprese. Převažoval také názor, že HERVy nejsou ani trankribovány - nejsou přepisovány do mRNA. Ze současných výzkumů však vyplývá, že HERVy jsou hojně přepisovány v mnoha různých tkáních lidského těla. Někdy mohou z této mRNA dokonce vznikat krátké peptidy, které pak mohou buňku ovlivňovat. Jak rozsáhlý je význam transkripce, je nyní předmětem dalších zkoumání., A retrovirus is an RNA virus using its own reverse transcriptase and integrase to produce DNA from its genome and incorporate it into the host’s genome. When a retrovirus is integrated in a germ line, it can become a part of the host genome. In human genome these elements occupy about 8 % of DNA and are called human endogenous retroviruses (HERVs). During evolution they mutated and lost their function to infect other cells. They were considered inactive (not expressed), however, transcription of HERVs in many different tissues in most human cells has recently been proved., and Mirka Famfulíková, Jan Pačes.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1343. Stopy sjezdového lyžování v půdě
- Creator:
- Miroslav Zeidler, Marek Banaš, Radim Hédl, and Houška, Jakub
- Format:
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Obecná ekologie, ekologie, horské ekosystémy, půda, sjezdové lyžování, ecology, mountain ecosystems, soil, downhill skiing, Hrubý Jeseník (Česko : pohoří), Hrubý Jeseník Mountains (Czechia), 2, and 574
- Language:
- Czech
- Description:
- Miroslav Zeidler, Marek Banaš, Radim Hédl, Jakub Houška.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1344. Středomořská kobylka v Praze na Karlově náměstí
- Creator:
- Pavel Pecina
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Životní prostředí a jeho ochrana, životní prostředí, hmyz, kobylky, environment, insects, Tettigonioidea, 2, and 502
- Language:
- Czech
- Description:
- Článek vychází z pozorování výskytu kobylky malé (Phaneroptera nana) v centru Prahy. Představuje blíže tento druh, jeho rozšíření, prazskou mikropopulaci a poznatky z chovu v insektáriu., This article is based on observations of the Mediterranean Katydid (Phaneroptera nana) in the centre of Prague. It presents the species, its spread, its Prague micropopulation and information on insectarium breeding in some detail., and Pavel Pecina.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1345. Střevlík uherský - jeho biologie, početnost, ochrana a péče o lokality
- Creator:
- Lukáš Čížek, Pokluda, Pavel, Kubáň, Vítězslav, Hauck, David, and Elek, Zoltán
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, zoologie, hmyz, střevlíkovití, ekologie, zoology, insects, ground beetles, ecology, Morava jižní (Česko), Moravia, Southern (Czechia), 2, and 59
- Language:
- Czech
- Description:
- Střevlík uherský (Carabus hugaricus hungaricus) je druhem dlouhostébelných panonských stepí. Patří mezi zvláště chráněné brouky a je rovněž druhem evropsky významným. V České republice přežívá už pouze na Pouzdřanské stepi a na Pálavě. V článku shrnujeme výsledky výzkumů jeho stanovištních preferencí, demografie a mobility, diskutujeme možnosti jeho ochrany a zároveň se dotýkáme bolestivého tématu ochranářské péče o lokality tohoto druhu., The Carabus hungaricus ground beetle is a highly endangered, dry-grassland specialist listed in the EU Habitats Directive. In the Czech Republic, the beetle survives on the last two sites including the Pouzdřany steppe, and the Pálava hills. Here we report results of extensive mark-recapture studies of this species, including its habitat preference, demography, and dispersal abilities. Furthermore, we discuss the options for its conservation and conservation management of the two inhabited sites., Lukáš Čížek ... [et al.]., and Pokračování čl. na str. CXV kuléru Živy 5/2014
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1346. Střevlík uherský - jeho biologie, početnost, ochrana a péče o lokality: (pokračování článku ze str. 222-225 této Živy)
- Creator:
- Lukáš Čížek, Pokluda, Pavel, Kubáň, Vítězslav, Hauck, David, and Elek, Zoltán
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, entomologie, střevlíkovití, entomology, ground beetles, Morava jižní (Česko), 2, and 59
- Language:
- Czech
- Description:
- Lukáš Čížek ... [et al.]. and Pokračování čl. ze str. 222-225 Živy 5/2014
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1347. Stříbrná medaile UK pro Vladimíra Hanáka
- Format:
- print, bez média, and svazek
- Type:
- article, zprávy, model:article, and TEXT
- Subject:
- Biologické vědy, Hanák, Vladimír, 1931-, zoologové, zoologists, Česko, Czechia, 2, and 57/59
- Language:
- Czech
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1348. Structural and functional changes in the photosynthetic apparatus of Chlamydomonas reinhardtii during nitrogen deprivation and replenishment
- Creator:
- Preininger, É., Kósa, A., Lőrincz, ZS., Nyitrai, P., Simon, J., Böddi, B., Keresztes, Á., and Gyurján, I.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, electron microscopy, nitrogen starvation, O2 evolution, 77K fluorescence, 2, and 581
- Language:
- Multiple languages
- Description:
- Nitrogen is an essential factor for normal plant and algal development. As a component of nucleic acids, proteins, and chlorophyll (Chl) molecules, it has a crucial role in the organization of a functioning photosynthetic apparatus. Our aim was to study the effects of nitrogen starvation in cultures of the unicellular green alga, Chlamydomonas reinhardtii, maintained on nitrogen-free, and then on nitrogen-containing medium. During the three-week-long degreening process, considerable changes were observed in the Chl content, the ratio of Chl-protein complexes, and photosynthetic activity of the cultures as well as in the ultrastructure of single chloroplasts. The regreening process was much faster then the degradation; total greening of the cells occurred within four days. The rate of regeneration depended on the nitrogen content. At least 50% of the normal nitrogen content of Tris-Acetate-Phosphate (TAP) medium was required in the medium for the complete regreening of the cells and regeneration of chloroplasts., É. Preininger, A. Kósa, Z. S. Lőrincz, P. Nyitrai, J. Simon, B. Böddi, Á. Keresztes, I. Gyurján., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1349. Structural and functional organization of the photosynthetic apparatus in halophytes with different strategies of salt tolerance
- Creator:
- Rozentsvet, O. A., Bogdanova, E. S., Ivanova, L. A., Ivanov, L. A., Tabalenkova, G. N., Zakhozhiy, I. G., and Nesterov, V. N.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, water content, salt stress, chlorophyll fluorescence, mesostructure, photoinhibition, 2, and 581
- Language:
- Multiple languages
- Description:
- The specific features of the structural and functional organisation of the photosynthetic apparatus (PSA) were studied in wild halophytes representing three strategies of salt tolerance: euhalophyte Salicornia perennans, crynohalophyte Limonium gmelinii, and glycohalophyte Artemisia santonica. The sodium content in aboveground parts of the plants corresponded to the strategy of salt tolerance. The photosynthetic cells of the euhalophyte were large and contained a higher number of chloroplasts than those in other species. In contrast, the number of cells per a leaf area unit was lower in S. perennans as compared to cryno- and glycohalophytes. Thereupon, the cell and chloroplast surface area per leaf area unit declined in the following sequence: A. santonica > L. gmelinii > S. perennans. However, the large cells of euhalophyte contained chloroplasts of larger sizes with 4- to 5-fold higher chlorophyll (Chl) content per chloroplast and Chl concentration in chloroplast volume unit. Also, chloroplasts of S. perennans were characterised by the higher content of glyco- and phospholipids. Qualitative composition of fatty acids (FA) in lipids isolated from the chloroplast-enriched fraction was similar in all three species; however, the index of unsaturation of FA was higher in glycohalophyte A. santonica than those in two other species. Under natural condition, PSA of all three halophytes showed high resistance to soil salinity. The results indicated tolerance of PSII to the photodamage in halophytes. The high rate of electron transport through PSII can be important to prevent oxidative damage of PSA in halophytes under strong light and hight temperature in vivo. Thus, the strategy of salt tolerance is provided by both the leaf anatomical structure and the ultrastructure of photosynthetic membranes, which is determined in particular by the specific composition of lipids., O. A. Rozentsvet, E. S. Bogdanova, L. A. Ivanova, L. A. Ivanov, G. N. Tabalenkova, I. G. Zakhozhiy, V. N. Nesterov., and Seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1350. Structure of scuttle fly communities (Diptera: Phoridae) in two habitats on a Mediterranean mountain
- Creator:
- García-Romera, Carlos and Barrientos, José A.
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, dvoukřídlí, Diptera, Phoridae, diversity, Montseny, beech forest, scrubland, 2, and 59
- Language:
- English
- Description:
- Phoridae (scuttle flies) are widely distributed, occur in many types of habitats and are ecologically versatile, which makes them an excellent bioindicator group for evaluating faunal diversity. The structure of scuttle fly communities was compared in two Mediterranean habitats in the Montseny Natural Park (Catalonia, Spain) that differ in vegetation and microclimate: beech forest and highland scrubland. 3684 male individuals belonging to 135 species of scuttle flies were identified. Scuttle flies were more abundant in beech forest than scrubland. Observed and estimated species richness were lower in scrubland than in beech forest, while diversity was similar in both habitats. Community evenness was greater in scrubland than beech forest. Therefore, the percentage of dominant and subdominant species was higher in scrubland than beech forest, while the percentage of rare species was higher in beech forest than scrubland. Scuttle fly species composition was significantly different in the two habitats, but it was similar among plots within the same habitat. Megaselia pectoralis (Wood, 1910) and Megaselia subpleuralis (Wood, 1909) were the dominant species in beech forest, while Megaselia pusilla (Meigen, 1830), Megaselia pumila (Meigen, 1830), Megaselia superciliata (Wood, 1910) and Megaselia diversa (Wood, 1909) were the dominant species in scrubland. Trophic specialization was higher in beech forest than scrubland. Saprophages were the dominant trophic group in beech forest, while fungivores and polyphages were dominant in scrubland. The high biodiversity of scuttle flies recorded in the Montseny Natural Park indicates that there is also a high diversity of other taxa there and that these Mediterranean mountains are of high conservation status., Carlos García-Romera, José A. Barrientos., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public