GABA-B receptor agonist SKF97541 exhibits age-dependent anticonvulsant and proconvulsant actions in developing rats. It suppressed tonic phase of generalized seizures induced by pentetrazol in 7-, 12- and 18-day-old rats and increased their latency in 7- and 12-day-old animals. Other results in 18-day-old animals are not so clear. SKF 97541 blocked the appearance of minimal clonic seizures, but tended to decrease latencies of both types of seizures. In addition, it significantly decreases latency of generalized seizures in adult rats. The mixed effects of SKF97541 are in agreement with those of baclofen but there are substantial differences between the actions of these two agonists in individual age groups., P. Mareš., and Obsahuje bibliografii a bibliografické odkazy
Sheep scab caused by the mite Psoroptes ovis (Hering) is a highly contagious disease of sheep. As a first step in developing a mite-derived vaccine for controlling the disease, the soluble antigens in mite extracts which induce an immune response in sheep were identified by electrophoretic and immunoblotting techniques. At least 22 proteins were present in P. ovis extracts as revealed by Coomassie Blue staining. Mite-infested sheep serum recognised six antigenic bands in the extracts with approximate relative molecular weights ranging from 12 to 183 kDa. A deeply staining band at 31.2 kDa and another at 41.8 kDa are of particular diagnostic value. Immunoblotting studies showed that there was no cross reactivity between P. ovis and two other ectoparasites of sheep in the UK, the sheep louse Bovicola ovis (Schrank) and the sheep tick Ixodes ricinus L.
Na řadě konkrétních příkladů ukážeme, že se sluneční soustava i galaxie velice pozvolna rozpínají rychlostí řádově srovnatelnou s Hubbleovou konstantou. To je samozřejmé V rozporu se zákonem zachování energie. Dále ukážeme, co by mohlo být zdrojem skryté energie způsobující toto rozpínání i zrychlující se rozpínání celého vesmíru., We give several factual examples showing that the Solar System and also galaxies expand very slowly by a speed comparable with the Hubble constant. This, of course, contradicts the law of ener gy conservation. Further, we show what could be the source of dark energy causing this expansion as well as the accelerating expansion of the whole universe., Michal Křížek., and Obsahuje seznam literatury
Ve druhé části článku předložíme další argumenty, které hovoří ve prospěch hypotézy, jež tvrdí, že skrytá energie nepůsobí jenom globálně, ale i lokálně. To naznačuje, že zákon zachování energie nemusí platit. Navíc ukážeme, že skrytá energie způsobující lokální expanzi gravitačně vázaných systémů může pocházet z nepatrně malé, ale kladné hodnoty gravitační aberace, jež je důsledkem konečné rychlosti šíření gravitační interakce a principu kauzality. Předložený mechanismus může i přispívat ke zrychlujícímu se rozpínání vesmíru., In the second part of this paper we give further examples showing that dark energy acts, not only globally, but also locally. This indicates that the law of energy conservation does not hold. Moreover, we demonstrate that the dark energy needed for an accelerated expansion of the universe may come from an extremely small but positive value of gravitational aberration which would result from a finite speed of gravitational interaction and from causality., Michal Křížek., and Obsahuje seznam literatury
Uvádíme a porovnáváme názory největších myslitelů antiky a středověku - Platóna, Aristotela, Augustina a Tomáše Akvinského - na povahu a vlastnosti času. Všímáme si, jak se jimi formulované názory a problémy odrážejí v současné fyzice., Pavel Macků, Jan Novotný., and Obsahuje seznam literatury
This study deals with reforms by Josef II, in particular with the abolition of the monasteries as recorded in contemporary sources supporting the reforms being carried out. The author selects some significant themes treated by the proponents of reform. The main theme is the criterion of human nature. Related themes include: monks’ asceticism, celibacy, monasteries as the quintessence of baroque piety, and mendicant orders., Petr Hasan., and Obsahuje bibliografické odkazy
The main characteristics of the Antimüllerian hormone from the points of view of biochemistry, molecular genetics, physiological functions and importance for diagnostics in reproductive endocrinology and related biomedical fields are reviewed. The role of the hormone in male and female development, its participation in oocyte maturation including selection of a dominant follicle are summarized, as well as its changes under various pathological situations in both sexes. The physiological changes of serum AMH leves in the life span in both sexes and their alterations under various pathological conditions are provided, too., R. Hampl, M. Šnajderová, T. Mardešić., and Obsahuje bibliografii a bibliografické odkazy
Research on brown adipose tissue and its hallmark protein, mitochondrial uncoupling protei n UCP1, has been conducted for half a century and has been traditionally studied in the Institute of Physiology (AS CR, Prague), likewise UCP2 residing in multiple tissues for the last two decades. Our group has significantly contributed to the elucidation of UCP uncoupling mechanism, fully dependent on free fatty acids (FFAs) within the inner mitochondrial membrane. Now we review UCP2 physiological roles emphasizing its roles in pancreatic β-cells, such as antioxidant role, possible tuning of redox homeostasis (consequently UCP2 participation in redox regulations), and fine regulation of glucose-stimulated insulin secretion (GSIS). For example, NADPH has been firmly established as being a modulator of GSIS and since UCP2 may influence redox homeostasis, it likely affects NADPH levels. We also point out the role of phospholipase iPLA2 isoform γ in providing FFAs for the UCP2 antioxidant function. Such initiation of mild uncoupling hypothetically precedes lipotoxicity in pancreatic β-cells until it reaches the pathological threshold, after which the antioxidant role of UCP2 can be no more cell-protective, for example due to oxidative stress-accumulated mutations in mtDNA. These mechanisms, together with impaired autocrine insulin function belong to important causes of Type 2 diabetes etiology., P. Ježek ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy