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231.
The functional classes (FCs) established according to the criteria of the New York Heart Association were tested for association with oxygen consumption, the state of central hemodynamics, and heart rate (HR) variability in coronary artery disease (CAD) patients. Oxygen consumption, central hemodynamics, and HR variability at rest and during exercise were assayed in 146 CAD patients and 30 healthy individuals (the control group). It was established that the peak oxygen consumption (VO2max), anaerobic threshold, pulmonary ventilation, systolic and minute blood volume at the threshold load (TL), and HR variability in a supine position significantly decrease and the total vascular peripheral resistance at rest and during exercise increases with increasing FC in CAD patients. The closest correlation of FC was revealed with physical working capacity, anaerobic threshold, age, and peak oxygen consumption. Moderate correlations were established with the chronotropic function of the heart at the threshold load, HR variability, the high- and low-frequency components of the cardiac rhythm at TL, pulmonary ventilation, stroke volume at rest and at TL, and the carbon dioxide ventilation equivalent at TL. In healthy individuals, the peak oxygen consumption closely correlated with the HR variability, the very low frequency component at TL, and physical capacity. With an increase in FC in CAD patients, peak oxygen consumption became more tightly associated with the chronotropic function and the hemodynamic components at TL than with the HR variability in a supine position or at TL. 相似文献
232.
Tomáš Gichner Zdeňka Patková Jiřina Száková Irena Žnidar Anita Mukherjee 《Environmental and Experimental Botany》2008,62(2):113-119
We have calibrated the alkaline protocol of the plant comet (Single Cell Gel Electrophoresis) assay as a method for detecting the extent of induced DNA damage in potato plants (Solanum tuberosum L. cultivar Korela). After 2 and 24 h treatments of the rooted cuttings with the heavy metal cadmium (Cd2+), a dose–response increase in DNA damage was noted versus controls in root nuclei. With a 24 h recovery period, the Cd2+-induced DNA damage in roots increased significantly. No significant increase in DNA damage was demonstrated in leaf nuclei after 24 h Cd2+ treatments, but continuous Cd2+ treatments for 2 weeks resulted in an increase in leaf DNA damage. This increase may be however associated with necrotic and apoptotic DNA fragmentation, as the affected plants had inhibited growth and distorted yellowish leaves. For comparison, the monofunctional alkylating agent ethyl methanesulphonate, and γ-rays were assessed for induced DNA damage. Analysis of the accumulation of cadmium by inductively coupled plasma optical emission spectrometry demonstrates that roots accumulate almost 9-fold more cadmium than aboveground parts of the rooted potato cuttings. This may explain the absence of Cd2+ genotoxicity in leaves after short-term treatments. 相似文献
233.
Janne Nikkilä Marko Sysi‐Aho Andrey Ermolov Tuulikki Seppänen‐Laakso Olli Simell Samuel Kaski Matej Orešič 《Molecular systems biology》2008,4(1)
Little is known about the human intra‐individual metabolic profile changes over an extended period of time. Here, we introduce a novel concept suggesting that children even at a very young age can be categorized in terms of metabolic state as they advance in development. The hidden Markov models were used as a method for discovering the underlying progression in the metabolic state. We applied the methodology to study metabolic trajectories in children between birth and 4 years of age, based on a series of samples selected from a large birth cohort study. We found multiple previously unknown age‐ and gender‐related metabolome changes of potential medical significance. Specifically, we found that the major developmental state differences between girls and boys are attributed to sphingolipids. In addition, we demonstrated the feasibility of state‐based alignment of personal metabolic trajectories. We show that children have different development rates at the level of metabolome and thus the state‐based approach may be advantageous when applying metabolome profiling in search of markers for subtle (patho)physiological changes. 相似文献
234.
Žuža Milena G. Milašinović Nikola Z. Jonović Marko M. Jovanović Jelena R. Kalagasidis Krušić Melina T. Bugarski Branko M. Knežević-Jugović Zorica D. 《Bioprocess and biosystems engineering》2017,40(11):1713-1723
Bioprocess and Biosystems Engineering - In this study, alcalase (protease from Bacillus licheniformis) immobilization by adsorption, enzyme crosslinking and covalent enzyme binding to activated... 相似文献
235.
Community assembly in Nothobranchius annual fishes: Nested patterns,environmental niche and biogeographic history
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Martin Reichard Michal Janáč Matej Polačik Radim Blažek Milan Vrtílek 《Ecology and evolution》2017,7(7):2294-2306
The assembly of local communities from regional species pools is shaped by historical aspects of distribution, environmental conditions, and biotic interactions. We studied local community assembly patterns in African annual killifishes of the genus Nothobranchius (Cyprinodontiformes), investigating data from 168 communities across the entire range of regionally co‐existing species. Nothobranchius are small fishes associated with annually desiccating pools. We detected a nested pattern of local communities in one region (Southern Mozambique, with Nothobranchius furzeri as the core and dominant species), but no nestedness was found in the second region (Central Mozambique, with Nothobranchius orthonotus being the dominant species). A checkerboard pattern of local Nothobranchius community assembly was demonstrated in both regions. Multivariate environmental niche modeling revealed moderate differences in environmental niche occupancy between three monophyletic clades that largely co‐occurred geographically and greater differences between strictly allopatric species within the clades. Most variation among species was observed along an altitudinal gradient; N. furzeri and Nothobranchius kadleci were absent from coastal plains, Nothobranchius pienaari, Nothobranchius rachovii, and Nothobranchius krysanovi were associated with lower altitude and N. orthonotus was intermediate and geographically most widespread species. We discuss implications for ecological and evolutionary research in this taxon. 相似文献
236.
Diet of wolvesCanis lupus Linnaeus, 1758 in Latvia was studied from 1997 to 2001 based on 302 scats and 107 stomachs. Wild ungulates (cervids and wild
boarSus scrofa) and beaverCastor fiber were the dominant prey. Cervids were found in 50% of samples (62% biomass), wild boar in 25% (21% biomass), beavers in 14%
(12% biomass). Wolves selected for wild boar, especially in winter when its ratio in the diet increased to 34% from 20% in
summer. It was a more common prey species in the east of the country. The ratio of beavers, small rodents and plant food was
higher in summer, which resulted in a broader food niche in summer than in winter (B = 2.53 versus 1.81, respectively). The
role of domestic animals in the wolf diet was minimal except for winter when they were consumed as carrion (13%). More than
1/3of all stomachs investigated were empty. The average weight of stomach contents was 972.8 g. The importance of the beaver
as an alternative prey is discussed. We conclude that wolves in Latvia prey mainly on wild animals and conflicts with livestock
owners are only occasional and/or local. 相似文献
237.
Haploid tobacco plants (cv. Samsun) form inflorescences with a larger number of flowers than diploid plants. Leaves of haploid
plants were shown to have lower free IAA level (by 40 %), higher peroxidase (by 160 %) and IAA-oxidase (by 70 %) activities
and produce less ethylene (by 25 %) than leaves of corresponding diploid plants. The increase of peroxidase activity in haploids
was due to the increase in the activity of the cathodic isozyme which is known to have high IAA-oxidase activity. It is proposed
that higher peroxidase/IAA-oxidase activity in haploid plants may take part in IAA catabolism, at least duringin vitro culture of haploid explants. Lowered IAA level and ethylene production may then be directly correlated with a larger number
of flower buds; as a higher IAA level is generally considered to act as a background inhibitor of flowering. 相似文献
238.
Escadafal C Olschläger S Avšič-Županc T Papa A Vanhomwegen J Wölfel R Mirazimi A Teichmann A Donoso-Mantke O Niedrig M 《PLoS neglected tropical diseases》2012,6(6):e1706
Crimean-Congo hemorrhagic fever (CCHF) is a zoonosis caused by a Nairovirus of the family Bunyaviridae. Infection is transmitted to humans mostly by Hyalomma ticks and also by direct contact with the blood or tissues of infected humans or viremic livestock. Clinical features usually include a rapid progression characterized by hemorrhage, myalgia and fever, with a lethality rate up to 30%. CCHF is one of the most widely distributed viral hemorrhagic fevers and has been reported in Africa, the Middle East and Asia, as well as parts of Europe. There is no approved vaccine or specific treatment against CCHF virus (CCHFV) infections. In this context, an accurate diagnosis as well as a reliable surveillance of CCHFV infections is essential. Diagnostic techniques include virus culture, serology and molecular methods, which are now increasingly used. The European Network for the Diagnostics of "Imported" Viral Diseases organized the first international external quality assessment of CCHVF molecular diagnostics in 2011 to assess the efficiency and accurateness of CCHFV molecular methods applied by expert laboratories. A proficiency test panel of 15 samples was distributed to the participants including 10 different CCHFV preparations generated from infected cell cultures, a preparation of plasmid cloned with the nucleoprotein of CCHFV, two CCHFV RNA preparations and two negative controls. Forty-four laboratories worldwide participated in the EQA study and 53 data sets were received. Twenty data sets (38%) met all criteria with optimal performance, 10 (19%) with acceptable performance, while 23 (43%) reported results showing a need for improvement. Differences in performance depended on the method used, the type of strain tested, the concentration of the sample tested and the laboratory performing the test. These results indicate that there is still a need for improving testing conditions and standardizing protocols for the molecular detection of Crimean-Congo hemorrhagic fever virus. 相似文献
239.
240.