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961.
Joanna Iwanicka Tomasz Iwanicki Marcin Kaczmarczyk Wodzimierz Mazur 《Polish journal of microbiology》2022,71(2):141
The rapidly spreading Coronavirus Disease 2019 (COVID-19) pandemic has led to a global health crisis and has left a deep mark on society, culture, and the global economy. Despite considerable efforts made to contain the disease, SARS-CoV-2 still poses a threat on a global scale. The current epidemiological situation caused an urgent need to understand the basic mechanisms of the virus transmission and COVID-19 severe course. This review summarizes current knowledge on clinical courses, diagnostics, treatment, and prevention of COVID-19. Moreover, we have included the latest research results on the genetic characterization of SARS-CoV-2 and genetic determinants of susceptibility and severity to infection. 相似文献
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963.
Maria Włodarska-Kowalczuk Jan Marcin Węsławski Jan Warzocha Urszula Janas 《Biodiversity and Conservation》2010,19(14):3991-4002
The effects of habitat loss on local species richness depend on the characteristics of the endangered system (including its
total species pool and the distribution of species among the habitats). The present study focuses on the species-poor southern
Baltic marine benthic biota. Macrobenthic samples were collected in three habitats: (1) soft bottom covered with vegetation;
(2) stony reefs; (3) unvegetated sands. Fourty one percent of 54 observed macrozoobenthic species were habitat specific, while
30% occurred in all three habitats. There were no significant differences in total species richness among the three habitats.
The accumulation curves plotted for subsets of data with selected habitats excluded lay below the curve plotted for the whole
dataset, but only in one case the 95% confidence intervals of the subset curve did not overlap with those plotted for the
whole dataset. The exclusion of samples from selected habitats produced a species richness drop ranging from 9 to 13%. The
present study showed that habitat loss in a species-poor area with a relatively large ratio of generalist species cannot produce
local species richness declines similar to those predicted for diverse marine systems. However, it must be emphasized that
in species-poor systems, the loss of ecological function accompanying habitat loss could be disproportionally higher than
that predicted based on decreases in species richness, as some functions are performed by a single species. 相似文献
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965.
Nicolas Boutard Arkadiusz Białas Aleksandra Sabiniarz Paweł Guzik Katarzyna Banaszak Artur Biela Marcin Bień Anna Buda Barbara Bugaj Ewelina Cieluch Anna Cierpich Łukasz Dudek Hans-Michael Eggenweiler Joanna Fogt Monika Gaik Andrzej Gondela Krzysztof Jakubiec Mirek Jurzak Charles-Henry Fabritius 《Bioorganic & medicinal chemistry letters》2019,29(4):646-653
In oncology, the “Warburg effect” describes the elevated production of energy by glycolysis in cancer cells. The ubiquitous and hypoxia-induced 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3) plays a noteworthy role in the regulation of glycolysis by producing fructose-2,6-biphosphate (F-2,6-BP), a potent activator of the glycolysis rate-limiting phosphofructokinase PFK-1. Series of amides and sulfonamides derivatives based on a N-aryl 6-aminoquinoxaline scaffold were synthesized and tested for their inhibition of PFKFB3 in vitro in a biochemical assay as well as in HCT116 cells. The carboxamide series displayed satisfactory kinetic solubility and metabolic stability, and within this class, potent lead compounds with low nanomolar activity have been identified with a suitable profile for further in vivo evaluation. 相似文献
966.
Interactions between the ectomycorrhizal fungus Laccaria laccata and the soil fungus Trichoderma virens in co-culture and in the rhizosphere of Pinus sylvestris seedlings growing in vitro were investigated by light and scanning electron microscopy. The growth of T. virens was inhibited in co-culture. Shortened, more branched and sometimes deformed or injured hyphae of T. virens were observed in the zone of inhibition. Two-month-old mycorrhizae of P. sylvestris/ L. laccata were inoculated with a conidial suspension of T. virens and examined at intervals of 7-24 h and 2, 3, and 6 days post-inoculation (p.i.). On non-mycorrhizal roots, conidia germination was high and long hyphae formed 3 days p.i. On mycorrhizal roots, short germ tubes were observed only sporadically. At 3 days p.i., the mantle hyphae of L. laccata grew towards the conidia and coiled around them. Extremely dense coils of hyphae were found around clusters of conidia. Deformation of conidia, breaks in conidial walls and their partial degradation were observed 6 days p.i. 相似文献
967.
Crystal structures of RNase H bound to an RNA/DNA hybrid: substrate specificity and metal-dependent catalysis 总被引:12,自引:0,他引:12
RNase H belongs to a nucleotidyl-transferase superfamily, which includes transposase, retroviral integrase, Holliday junction resolvase, and RISC nuclease Argonaute. We report the crystal structures of RNase H complexed with an RNA/DNA hybrid and a mechanism for substrate recognition and two-metal-ion-dependent catalysis. RNase H specifically recognizes the A form RNA strand and the B form DNA strand. Structure comparisons lead us to predict the catalytic residues of Argonaute and conclude that two-metal-ion catalysis is a general feature of the superfamily. In nucleases, the two metal ions are asymmetrically coordinated and have distinct roles in activating the nucleophile and stabilizing the transition state. In transposases, they are symmetrically coordinated and exchange roles to alternately activate a water and a 3'-OH for successive strand cleavage and transfer by a ping-pong mechanism. 相似文献
968.
Dominika M. Wilczyska Frank Abrahamsen Agnieszka Popawska Piotr Aschenbrenner Marcin Dornowski 《Biology of sport / Institute of Sport》2022,39(3):571
The aim of the current study is to determine how the level of state and trait anxiety differs between youth athletes of different performance levels and furthermore whether there are correlations between performance levels and psychomotor variables in the selected tasks. A sample of 97 boys, aged 11–12 years, practising soccer represented two groups: A – high performance level and B – lower performance level. Participants completed a state and trait anxiety inventory and performed selected psychomotor tests. The analyses demonstrated that the higher the levels of anxiety were, the shorter was the response time and more accurate were the responses in selected psychomotor tests. For the whole group, r = -0.224, p < 0.05, and for group B, r = -0.333, p < 0.05. Moreover, the findings showed a moderator effect of level (group A vs B) on reaction time, which was almost significant in state anxiety and significant in trait anxiety. For group B, trait anxiety was negatively related to reaction time (b = -0.002, SE = 0.001, t = -2.93, p = .004, 95% CI [-0.004, -0.001]). This means that the higher the trait anxiety was, the shorter was the reaction time in group B, but there was no significant effect in group A. The results of the study confirmed the negative correlation between the trait and state anxiety and reaction time. The higher the anxiety was, the shorter was the response time of child soccer players. Future research should determine whether athletes’ performance levels do affect performance under stress and replicate the study with different samples such as girls and different sport disciplines. 相似文献
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970.