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Jan J. Rybczyński Bożenna Borkowska Agnieszka Fiuk Helena Gawrońska Eleonora Śliwińska Anna Mikuła 《Acta Physiologiae Plantarum》2007,29(5):445-453
In this work, the effect of sucrose on photosynthetic activity during in vitro culture was studied. Experiments were carried
out using uniform somatic embryo-derived germlings of Gentiana kurroo (Royle) confirmed by chromosome counting and flow cytometry technique. Photosynthetic activity was measured by chlorophyll
a fluorescence and gas exchange method. The efficiency of photosynthetic apparatus as measured by the ratio F
v/F
m, Yield and qP (light phase of photosynthesis) was the highest when the medium was supplemented with 0.3% sucrose which well
corresponded with plant gas exchange. Taking all data into consideration for the best development of photosynthetic apparatus
and the most efficient of net photosynthesis of studied germlings would be medium supplemented with 0.2–0.4% of sucrose. 相似文献
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Mikuła-Pietrasik J Kuczmarska A Rubiś B Filas V Murias M Zieliński P Piwocka K Książek K 《Free radical biology & medicine》2012,52(11-12):2234-2245
Resveratrol (3,4',5-trihydroxy-trans-stilbene; RVT) is a natural phytoestrogen known to modulate the rate of senescence in cultured cells. The mechanism by which RVT affects this process is still elusive. In this paper we used human peritoneal mesothelial cells (HPMCs) to examine the effect of RVT (0.5 and 10 μM) on their growth and senescence, with particular emphasis paid to parameters associated with oxidative stress. The results showed that RVT used at a concentration of 0.5 μM (but not at 10 μM) markedly improved HPMC growth capacity, as evidenced by elevated expression of PCNA antigen, augmented fraction of cells in the S phase of the cell cycle, and increased number of divisions achieved before senescence. These effects coincided with diminished expression and activity of senescence-associated β-galactosidase but were not associated with changes in the telomere length and an incidence of apoptosis. Moreover cells exposed to 0.5 μM RVT were characterized by increased release of reactive oxygen species, which was accompanied by up-regulated biogenesis of mitochondria and collapsed mitochondrial membrane potential. At the same time, they displayed increased activity of superoxide dismutase and reduced DNA damage (8-OH-dG and γ-H2A.X level). The efficiency of 8-OH-dG repair was increased which could be related to increased activity of DNA glycosylase I (hOgg1). As shown using RT-PCR, expression of hOgg1 mRNA in these cells was markedly elevated. Collectively, our results indicate that delayed senescence of HPMCs exposed to RVT may be associated with mobilization of antioxidative and DNA repair mechanisms. 相似文献
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Experiments were carried out with three-year-old embryogenic suspension culture of Gentiana pannonica Scop. The initial explant for the suspension determinated both the embryogenic character and embryo production. Cultures
were initiated by culture of hypocotyl, cotyledon and root explants on MS (Murashige and Skoog 1962) medium supplemented with
1.0 mg·l−1 Kinetin and 0.5 mg·l−1 2,4-D, later transferred and maintained in liquid MS medium with 1.0 mg·l−1 Dicamba, 0.1 mg·l−1 NAA, 2.0 mg·l−1 BAP and 80.0 mg·l−1 AS. Regeneration medium included 0.0–1.0 mg·l−1 GA3+0.0−2.0 mg·l−1 Kin.+0.0−160 mg·l−1 AS.
In these culture conditions, the effect of the explant was found to be the most important factor. The curve of growth, growth
coefficient and % of participation of various size aggregates differed in the studied suspensions. Flow cytometry revealed
various DNA content in nuclei from praembryogenic mass depending on the explant origin. To complete embryogenesis the medium
was changed from liquid to solidified in the presence of the same plant growth regulators combination required. The most embryogenic
culture appeared hypocotyl-derived and it yielded the highest number of somatic embryos. The suspension culture originating
from root proliferated the highest number of embryogenic cell clusters but did not produce embryos for fraction 120–450 μm.
One hundred mg of suspension of the fraction that was larger than 450 μm yielded 309, 175, 123 embryos for the following suspensions:
root-, cotyledon-, hypocotyl-derived, respectively. Almost 50 % of non-deformed fully developed embryos from all studied suspensions
passed conversion into germling stage and finally plants were regenerated. 相似文献
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Usui T Yanagisawa S Ohguchi M Yoshino M Kawabata R Kishimoto J Arai Y Aida K Watanabe H Hayase F 《Bioscience, biotechnology, and biochemistry》2007,71(10):2465-2472
The alpha-dicarbonyl compounds formed in the degradation of glucose and fructose were analyzed by HPLC using 2,3-diaminonaphthalene as derivatizing reagent, and identified as glucosone (GLUCO), 3-deoxyglucosone (3DG), 3-deoxyxylosone (3DX), tetrosone (TSO), triosone (TRIO), 3-deoxytetrosone (3DT), glyoxal (GO), and methylglyoxal (MGO). The results suggest that alpha-dicarbonyl compounds were formed from glucose via non-oxidative 3-deoxyglucosone formation and oxidative glucosone formation in glucose degradation. In addition, TRIO, GO, and MGO were also formed from glyceraldehyde as intermediate. The alpha-dicarbonyl compounds might be formed from glucose via these pathways in diabetes. 相似文献
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Between recognition and redistribution: disability, (human) rights,and struggles over welfare in Serbia 下载免费PDF全文
Marek Mikuš 《The journal of the Royal Anthropological Institute》2018,24(2):293-312
This article analyses the discourse surrounding, implementation of, and struggles over the new disability policy in Serbia to show how its founding principles of human rights became partially co‐opted by neoliberal welfare restructuring. As a result, it sought to make disabled people not only equal but also economically ‘independent’ in the sense of relying on wage labour instead of welfare. Owing to its inadequate assumptions and instruments, the policy has largely failed to deliver on these objectives. Disabled people mobilized against neoliberalization by defending material welfare entitlements inherited from Yugoslav socialism. At the same time, they appropriated the register of human rights to demand a substantive political and civic equality. This points to the possibility of rights‐based projects that fuse rather than oppose the politics of recognition and redistribution. 相似文献
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Damir Viličić Frano Kršinić Marina Carić Nenad Jasprica Svjetlana Bobanović-Ćolić Josip Mikuš 《Hydrobiologia》1995,304(1):9-22
Gruž Bay (south-eastern Adriatic) is moderately eutrophicated, mostly by discharge from the karst river Ombla. Input of inorganic
nitrogen might be attributed to enrichment from the open sea during strong and continuous north winds in winter 1988/89. Annual
succession of primary producers, herbivores and decomposers was defined by seven stages and induced by specific physical-chemical
characteristics. In the period April–August, biological production was mostly due to small size fractions of phytoplankton
and zooplankton. Recycling of planktonic biomass occurred in September, of allochtonous organic matter in February and March. 相似文献
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The Izu Islands of southcentral Japan are thought to fall within the distribution range of Neoporphyra dentata. However, the gametophytic blades of Bangiales collected from Shikinejima and Hachijojima, Izu Islands, were identified as Neoporphyra haitanensis in our previous study. Thus, it became uncertain whether N. dentata is distributed in the Izu Islands, including Shikinejima. To clarify whether N. dentata grows on Shikinejima, we conducted a further distribution survey of N. dentata on the island. The morphological features of the blade samples collected from an additional sampling site on Shikinejima were more similar to those of N. dentata than to those of N. haitanensis: the blade thickness and the division formula of spermatangia resembled those of the former species rather than the latter species. However, the division formula of zygotosporangia was different from those of either species. The phylogenetic analyses of the rbcL gene indicated that the samples were resolved in a clade including N. dentata collected from Shirahama, Chiba Prefecture, and Enoshima, Kanagawa Prefecture, Honshu, Japan. The p-distances of the chloroplast rbcL gene and nuclear 18S rRNA also supported identification of the samples as N. dentata. The results demonstrated that N. dentata is also distributed on Shikinejima with co-occurring N. haitanensis, and that the island materials of the two species are genetically different from other materials of the two species, respectively. 相似文献