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29562. The impact of four different classes of anesthetics on the mechanisms of blood pressure regulation in normotensive and spontaneously hypertensive rats
- Creator:
- Bencze, M., Behuliak, M, and Josef Zicha
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, nervový systém, oxid dusnatý, nitric oxide, sympathetic nervous system, renin-angiotensin system, conscious rats, pentobarbital, isoflurane, ketaminexylazine, chloralose-urethane, 14, and 612
- Language:
- English
- Description:
- M. Bencze, M. Behuliak, J. Zicha. and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29563. The impact of lifestyle-related risk factors on cardiac response to ischemia and possibilities to restore impaired ischemic tolerance
- Creator:
- Ravingerová, T., Slávka Čarnická, Mária Nemčeková, Ledvényiová, V., Adriana Adameová, Khandelwal, V. K. M., Zálešák, M., and Kolář, F.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, lifestyle risk factors, myocardial ischemia, gender-related differences, cardiac adaptation, pleiotropic effects, 14, and 612
- Language:
- English
- Description:
- Risk factors (RF) of cardiovascular diseases associated with modern lifestyle, such as stress, chronically increased blood pressure, hyperglycemia and dyslipidemia have a negative impact on the heart exposed to ischemia: their may facilitate its lethal injury (myocardial infarction) and occurrence of sudden death due to ventricular arrhythmias. On the other hand, some stressful stimuli related to RF including reactive oxygen species, transient episodes of ischemia (hypoxia), high glucose and other may play a dual role in the pathogenesis of ischemia/reperfusion (I/R) injury (IRI). Besides their deleterious effects, these factors may trigger adaptive processes in the heart resulting in greater resistance against IRI, which is also a characteristic feature of the female myocardium. However, sensitivity to ischemia is increasing with age in both genders. Current research indicates that comorbidity related to lifestyle may impair the cardiac response to acute ischemia not only by interference with pathophysiological mechanisms of IRI per se, but via suppression of intrinsic protective mechanisms in the heart and its ability to tolerate the ischemic challenges, although the role of RF has not been unequivocally proven. Moreover, even pathologically altered myocardium need not completely lose its adaptive potential. In addition, increased ischemic tolerance can be induced by the pleiotropic (independent of the primary) effects of some hypolipidemic and antidiabetic drugs, even in the diseased myocardium. This review addresses the issue of the impact of RF on cellular cardioprotective mechanisms and the possibilities to restore adaptive potential in subjects challenged with several RF. Reactivation of adaptive processes in the myocardium taking into consideration gender and age can contribute to optimalization of antiischemic therapy., T. Ravingerová, ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29564. The impact of the retention curve hysteresis on prediction of soil water dynamics
- Creator:
- Dohnal, Michal, Dušek, Jaromír, and Vogel, Tomáš
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- hysteresis, hydraulic properties, soil water pressure development, inverse modeling, hystereze, hydraulické charakteristiky, dynamika půdní vody, and inverzní modelování
- Language:
- Slovak
- Description:
- The main objective of this study is to assess the effect of hysteresis of soil hydraulic properties on model predictions of soil water movement in a variably saturated soil. The model predictions are generated by the S1D model, which is based on numerical solution of one-dimensional Richards’ equation. The analysis is made for a loamy sand soil located in a small headwater catchment. The model is used to simulate the development of soil water pressure during three successive vegetation seasons. Three major simulation scenarios are formulated: the first scenario assumes no hysteresis in soil hydraulic properties, the second scenario involves a predefined hypothetical hysteresis, while the third scenario is based on optimized hysteresis, determined through the inverse modeling procedure. The analysis of the simulation results suggests that, in our case, ignoring hysteresis does not lead to any significant deviation of the model predictions from the observed soil water system responses. and Možnosti efektivně matematicky modelovat proudění vody v přirozených půdních formacích omezuje komplikovanost určení půdních hydraulických charakteristik, a to nejen s ohledem na jejich prostorovou a časovou variabilitu, ale také hysterezi. Příspěvek je zaměřen na testování vlivu hystereze na výsledky simulací proudění půdní vody v podmínkách malého horského povodí. Numerický model S1D, řešící Richardsovu rovnici v jednorozměrném tvaru, byl použit k výpočtu sezónního vývoje tlaku půdní vody. V simulacích byla alternativně uvažována hystereze retenční křivky. Odchylky mezi odezvami modelu a měřeními byly minimalizovány optimalizací scaling faktorů. Rozsáhlý srovnávací soubor uskutečněných optimalizací umožnil posoudit rozdíly modelové odezvy dvou hysterezních a jedné nehysterezní varianty a kvantifikovat dopad zanedbání hystereze na přesnost předpovědi modelu. Neuvažování hystereze v našem případě nezhoršuje schopnost modelu popsat změny půdní vlhkosti.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29565. The impact of the structure of the education system on the development of educational inequalities in the Czech Republic
- Creator:
- Straková, Jana
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- student achievement, socio-economic status, selectivity of education system, and teaching attitudes
- Language:
- Czech
- Description:
- The aim of this paper is to explore the impact of the structure of the Czech education system on the development of the relationship between a student's achievement and his/her family background. It compares the strength of the relationship between student achievement and a student's family background in various stages of his/her education career (grades 4, 8 and 10) in the Czech Republic and in systems without early tracking that also exhibit high student performance (Canada, Nordic countries). In addition, the paper tests a hypothesis that systems with different levels of tracking differ not only in their structure but also in teaching methods and teachers' attitudes. The analysis was conducted on data sets from the IEA PIRLS 2001, the IEA TIMSS 1999, and the OECD PISA 2003.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29566. The impact of treated wastewater and biosolids from the municipal wastewater treatment plant on water and carbon dioxide effluxes from soils
- Creator:
- Fér, Miroslav, Kodešová, Radka, Klement, Aleš, and Nikodem, Antonín
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- soil respiration, sewage sludge, composted sewage sludge, irrigation, and soil properties
- Language:
- Slovak
- Description:
- The goal of this study was to evaluate the effect of products from a municipal wastewater treatment plant on the H2O and CO2 effluxes from two soils. The net H2O and CO2 effluxes were measured at the surface of nine beds with two different soils (Cambisol and Arenosol) and two crops (maize or vegetables). Soils in some beds were amended with stabilized sewage sludge (bed with Cambisol and maize) or composted sewage sludge (two beds with Cambisol and both crops) or were irrigated with treated wastewater (two beds with Cambisol and both crops, and one bed with Arenosol and vegetable). Remaining beds were irrigated with tap water (two beds with Cambisol and both crops, and one bed with Arenosol and vegetable). While stabilized and composted sewage sludge positively affected the CO2 emission, the effect of treated wastewater was not confirmed. Different treatments had negligible effect on the water efflux, which was mainly affected by the plant canopy that influence the temperature of the soil surface. Statistical analyses showed that trends of the CO2 efflux with respect to various scenarios measured on different days changed during the season. No significant correlations were found between the average H2O and CO2 effluxes and measured soil properties.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29567. The importance of age and statin therapy in the interpretation of Lp-PLA2 in ACS patients, and relation to CRP
- Creator:
- Janka Franeková, Jiří Kettner, Kubíček, Z., and Antonín Jabor
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, biologické markery, akutní koronární syndromy, biological markers, acute coronary syndromes, plaque, atherosclerotic, c-reactive protein, phospholipase A2, 14, and 612
- Language:
- English
- Description:
- C-reactive protein (CRP) is a marker of arterial inflammation while lipoprotein-associated phospholipase A2 (Lp-PLA2) is related to plaque instability. The aim of this study was to evaluate the correlation between the risk of unstable plaque presenting as acute coronary syndrome (ACS) and Lp-PLA2, and to assess the influence of statins on interpretation of Lp-PLA2. A total of 362 consecutive patients presenting to the emergency department (ED) with acute chest pain suggestive of ACS were evaluated by cardiologists as STEMI, NSTEMI, or unstable angina, and non- ACS. Serum biomarkers measured on admission: troponin I, Creactive protein (Abbott), and Lp-PLA2 (DiaDexus). Four groups were defined according to the final diagnos-; non- ACS/statin+. Lp-PLA2 was highest in ACS/statin- group; statins decreased Lp-PLA2 both in ACS and non-ACS of about 20 %. Lp- PLA2 was higher in ACS patients in comparison with non-ACS patients group without respect to statin therapy (p<0.001). Lp- PLA2 predicted worse outcome (in terms of acute coronary syndrome) effectively in patients up to 62 years; limited prediction was found in older patients. C-reactive protein (CRP) failed to discriminate four groups of patients. Statin therapy and age should be taken into consideration while interpreting Lp-PLA2 concentrations and lower cut-off values should be used for statintreated persons., J. Franeková, J. Kettner, Z. Kubíček, A. Jabor., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29568. The importance of blue light for leaf area expansion, development of photosynthetic apparatus, and chloroplast ultrastructure of Cucumis sativus grown under weak light
- Creator:
- Wang, X. Y., Xu, X. M., and Cui, J.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, okurka setá, photosynthesis, Cucumis sativus, fluorescence transient, grana, JIP test, photosynthetic characteristics, 2, and 581
- Language:
- Multiple languages
- Description:
- The objective of this study was to evaluate the significance of blue light (B) in the growth and photosynthetic capacity of cucumber. Gas exchange, chlorophyll (Chl) fluorescence kinetics, chloroplast ultrastructure, and leaf growth were investigated to explore the influence of three different light qualities of light emitting diodes (LEDs) on plant morphogenesis and the development of photosynthetic apparatus in cucumber (Cucumis sativus) leaves from emergence to full expansion under weak light [50 μmol(photon) m-2 s-1]. We found that B could significantly increase the leaf area (LA), shoot elongation, Chl a/b, net photosynthetic rate, and stomatal conductance (g s). In addition, the comparisons of maximal quantum yield of PSII photochemistry and the photosynthetic performance index between B-, W (white light)-, and R (red light)-grown leaves suggested that B was essential for the development of photosynthetic apparatus under weak light. B-grown leaves had the lowest Chl content under weak light, however, they had well-developed chloroplasts with the highest degree of stacked lamellae and the lowest starch accumulation. This could explain to a considerable extent the highest net photosynthetic rate per Chl unit. The results demonstrated that B optimized photosynthetic performance by improving the photosynthetic rate, increasing LA, and prolonging active photosynthesis duration under low irradiance. Therefore B is necessary to ensure healthy development of chloroplasts and highly efficient photosynthetic functions in cucumbers under a weak light environment. More importantly, our study also provided theoretical and technical support for the development of light environmental control technology., X. Y. Wang, X. M. Xu, J. Cui., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29569. The importance of rip-rap for round goby invasion success - a field habitat manipulation experiment
- Creator:
- Roche, Kevin, Šlapanský, Luděk, Trávník, Mirek, Janáč, Michal, and Jurajda, Pavel
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- bank stabilisation, habitat preference, habitat restoration, invasive fish species, mitigation, and potamalisation
- Language:
- English
- Description:
- In a recent study, we showed how local-scale climate change impacts (increased temperature, reduced rainfall, shifts in peak rainfall) affected the hydrology of a channelised lowland European river (reduced flow, reduction in flood events, increased siltation, macrophyte growth), allowing native fish species to recolonise the bankside zone and reduce the density of invasive round goby Neogobius melanostomus by effectively removing its preferred habitat, rip-rap bank stabilisation. Here, we report on a follow-on study whereby stretches of the newly vegetated bank were stripped back to clean rip-rap to assess whether presence/absence of rip-rap was the major factor affecting non-gobiid, tubenose goby Proterorhinus semilunaris and round goby abundance. Our results confirmed rip-rap as a major factor increasing round goby abundance, and hence invasion success, on European rivers, while vegetated banks saw an increase in the abundance and diversity of non-gobiid species. While tubenose gobies showed no preference for habitat type, their numbers were significantly reduced in rip-rap colonised by larger and more aggressive round gobies. We discuss our results in light of recent artificial bank restoration measures undertaken on the Danube and Rhine and the potential role of round goby as a flagship species for cost-effective, large scale river bank restoration projects with multiple ecosystem benefits.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29570. The incidence of metabolic syndrome in obese czech children: the importance of early detection of insulin resistance using homeostatic indexes HOMA-IR and QUICKI
- Creator:
- Dalibor Pastucha, Radka Filipčíková, Dagmar Horáková, Lenka Radová, Zlatko Marinov, Jana Malinčíková, Kocvrlich, M., Horák, S., Marcela Bezdičková, and Miloš Dobiáš
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, obesity, metabolic syndrome, HOMA-IR, QUICKI, children, adolescents, 14, and 612
- Language:
- English
- Description:
- Common alimentary obesity frequently occurs on a polygenic basis as a typical lifestyle disorder in the developed countries. It is associated with characteristic complex metabolic changes, which are the cornerstones for future metabolic syndrome development. The aims of our study were 1) to determine the incidence of metabolic syndrome (based on the diagnostic criteria defined by the International Diabetes Federation for children and adolescents) in Czech obese children, 2) to evaluate the incidence of insulin resistance according to HOMA-IR and QUICKI homeostatic indexes in obese children with and without metabolic syndrome, and 3) to consider the diagnostic value of these indexes for the early detection of metabolic syndrome in obese children. We therefore performed anthropometric and laboratory examinations to determine the incidence of metabolic syndrome and insulin resistance in the group of 274 children with obesity (128 boys and 146 girls) aged 9-17 years. Metabolic syndrome was found in 102 subjects (37 %). On the other hand, the presence of insulin resistance according to QUICKI <0.357 was identified in 86 % and according to HOMA-IR >3.16 in 53 % of obese subjects. This HOMA-IR limit was exceeded by 70 % children in the MS(+) group, but only by 43 % children in the MS(–) group (p<0.0001). However, a relatively high incidence of insulin resistance in obese children without metabolic syndrome raises a question whether the existing diagnostic criteria do not falsely exclude some cases of metabolic syndrome. On the basis of our results we suggest to pay a preventive attention also to obese children with insulin resistance even if they do not fulfill the actual diagnostic criteria for metabolic syndrome., D. Pastucha, ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public