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71.
Some nonlinear characteristics of heart rate variability in the course of functional tests with physical exercise are described. Two groups of volunteers participated in the tests: a control group of 32 healthy subjects (group 1) and a group of 35 coronary heart disease (CHD) patients (group 2). Two series of experiments were performed for each group. An active orthostatic test (AOT) was used in the first series, and a gradually growing physical load on a bicycle ergometer (bicycle ergometer test, BET), in the second series. Along with statistical indices of heart rate (the mean RR interval and standard deviation), nonlinear indices of heart rate were estimated: the correlation dimensionality (D 2) and approximate entropy (ApEn). Trends of the changes in nonlinear indices of heart rate have been found. The D 2 and ApEn decreased in both groups of subjects during the AOT and BET under the maximum load. However, the groups of healthy subjects and CHD patients differed in the reactivity of indices, the amplitude of changes in nonlinear indices being narrower in the latter group than in group 1. Differently directed shifts in standard deviation (SDNN) and nonlinear indices have been found. Thus, the data obtained with the use of nonlinear heart rate characteristics show that heart rate under physical load is more multivariate and diverse in healthy subjects at rest and the amplitude of changes during the AOT and BET is greater than in CHD patients, which is a result of the specific autonomic control of heart activity in cardiovascular pathologies. 相似文献
72.
Kovačević Milijana Jovanović Živko Andrejić Gordana Dželetović Željko Rakić Tamara 《Plant and Soil》2020,453(1-2):297-312
Plant and Soil - Phragmites australis grows as a pioneer plant species in several mine and flotation tailings ponds distinguished by extremely high concentrations of metals. The main goals of this... 相似文献
73.
74.
Jar KŘíŽenecký 《Development genes and evolution》1913,37(4):629-634
Ohne Zusammenfassung 相似文献
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Anna Chrtková-Žertová 《Folia Geobotanica》1973,8(3):249-253
In the southern parts of Scandinavia there occur two species of theVicia cracca L. complex:Vicia cracca L., represented by the chromosome race 2n=28, andV. oreophila ?ertová. WhereasV. oreophila predominantly inhabits habitats of primary character, especially near the coast, the tetraploid race ofV. cracca, which is the commonest in other parts of area, occurs predominantly on sites of secondary character, such as the borders of paths, roads, meadows and bushy places. The two species differ in several characters. 相似文献
77.
Anna Chrtková-Žertová 《Folia Geobotanica》1971,6(2):215-216
Four new taxa in the variable speciesLotus corniculatus L. has been described: var.alandicus Chrtková-?ertová, var.norvegicus Chrtková-?ertová, var.fallax Chrtková-?ertová and var.posoniensis Chrtková-?ertová. 相似文献
78.
Dr. Jaroslav KŘiŽenecký 《Development genes and evolution》1924,101(4):621-665
Ohne Zusammenfassung 相似文献
79.
Invasive round goby Neogobius melanostomus has sex‐dependent locomotor activity and is under‐represented in catches from passive fishing gear compared with seine catches 下载免费PDF全文
Jakub Žák Tomáš Jůza Petr Blabolil Roman Baran Daniel Bartoň Vladislav Draštík Jaroslava Frouzová Michaela Holubová Henk A. M. Ketelaars Luboš Kočvara Jan Kubečka Tomáš Mrkvička Milan Muška Milan Říha Zuzana Sajdlová Marek Šmejkal Michal Tušer Mojmír Vašek Lukáš Vejřík Ivana Vejříková Arco J. Wagenvoort 《Journal of fish biology》2018,93(1):147-152
The higher proportion of males of the invasive round goby Neogobius melanostomus in samples from two activity selective passive fishing gears compared with one activity non‐selective fishing gear in three Dutch lakes is related to higher male locomotory activity and is a sex‐dependent trait. This difference in activity reflects the different ecology of male and female N. melanostomus. 相似文献
80.