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排序方式: 共有622条查询结果,搜索用时 31 毫秒
41.
Simona Littnerova Petr Kala Jiri Jarkovsky Lenka Kubkova Krystyna Prymusova Petr Kubena Martin Tesak Ondrej Toman Martin Poloczek Jindrich Spinar Ladislav Dusek Jiri Parenica 《PloS one》2015,10(4)
Aim
To compare the prognostic accuracy of six scoring models for up to three-year mortality and rates of hospitalisation due to acute decompensated heart failure (ADHF) in STEMI patients.Methods and Results
A total of 593 patients treated with primary PCI were evaluated. Prospective follow-up of patients was ≥3 years. Thirty-day, one-year, two-year, and three-year mortality rates were 4.0%, 7.3%, 8.9%, and 10.6%, respectively. Six risk scores—the TIMI score and derived dynamic TIMI, CADILLAC, PAMI, Zwolle, and GRACE—showed a high predictive accuracy for six- and 12-month mortality with area under the receiver operating characteristic curve (AUC) values of 0.73–0.85. The best predictive values for long-term mortality were obtained by GRACE. The next best-performing scores were CADILLAC, Zwolle, and Dynamic TIMI. All risk scores had a lower prediction accuracy for repeat hospitalisation due to ADHF, except Zwolle with the discriminatory capacity for hospitalisation up to two years (AUC, 0.80–0.83).Conclusions
All tested models showed a high predictive value for the estimation of one-year mortality, but GRACE appears to be the most suitable for the prediction for a longer follow-up period. The tested models exhibited an ability to predict the risk of ADHF, especially the Zwolle model. 相似文献42.
43.
Dušan Gömöry Roman Longauer Ladislav Paule Diana Krajmerová Jarmila Schmidtová 《Biodiversity and Conservation》2010,19(7):2025-2038
The study focuses on geographical patterns of genetic variation at allozyme loci common for four main tree species of Central
Europe (Norway spruce, silver fir, common beech and sessile oak). Moving-window averaging of four indicators of allelic richness
and diversity (proportion of polymorphic loci, mean number of alleles per locus, effective number of alleles and expected
heterozygosity) with window size of 50 × 50 km was used to identify the patterns. Moreover, local genetic divergence was assessed
using the G
ST
(Nei, Molecular population genetic and evolution, Amsterdam and Oxford, North-Holland, 1975) and D
j
(Gregorius and Roberds, Theor Appl Genet 71:826–834, 1986) statistics for common beech and silver fir, where raw genotype data were available. Spatial patterns of diversity and allelic
richness were quite similar. Romanian Carpathians were identified as the most important hotspot of genetic diversity and evolutionary
divergence in Central Europe. Implications for genetic conservation are briefly discussed. 相似文献
44.
Ol’ga Vančová Ladislav Bačiak Svatava Kašparová Jarmila Kucharská Hector H. Palacios Jaromír Horecký Gjumrakch Aliev 《Journal of cellular and molecular medicine》2010,14(11):2667-2674
Brain energy disorders can be present in aged men and animals. To this respect, the mitochondrial and free radical theory of aging postulates that age‐associated brain energy disorders are caused by an imbalance between pro‐ and anti‐oxidants that can result in oxidative stress. Our study was designed to investigate brain energy metabolism and the activity of endogenous antioxidants during their lifespan in male Wistar rats. In vivo brain bioenergetics were measured using 31P nuclear magnetic resonance (NMR) spectroscopy and in vitro by polarographic analysis of mitochondrial oxidative phosphorylation. When compared to the young controls, a significant decrease of age‐dependent mitochondrial respiration and adenosine‐3‐phosphate (ATP) production measured in vitro correlated with significant reduction of forward creatine kinase reaction (kfor) and with an increase in phosphocreatine (PCr)/ATP, PCr/Pi and PME/ATP ratio measured in vivo. The levels of enzymatic antioxidants catalase, GPx and GST significantly decreased in the brain tissue as well as in the peripheral blood of aged rats. We suppose that mitochondrial dysfunction and oxidative inactivation of endogenous enzymes may participate in age‐related disorders of brain energy metabolism. 相似文献
45.
L’ubica Halušková Katarína Valentovičová Jana Huttová Igor Mistrík Ladislav Tamás 《Plant Growth Regulation》2010,62(1):59-64
All of the analyzed heavy metals significantly inhibited root growth, but in addition to Cd exposure an elevated IAA-POD activity
was detected under Co, Cu and Hg treatment, while Ni and Pb inhibited its activity. The Cd-induced IAA-POD activity increased
from the root apex towards to the mature region of root tips. However similar or even more severe root growth inhibition was
observed by exogenously applied IAA, IAA-POD activity was activated only at high IAA concentrations. Elevated Cd-induced H2O2 production was detected both in the absence or in the presence of IAA in the reaction mixture, but in the case of IAA as
a possible substrate for PODs the production of H2O2 increased markedly just in the Cd-treated roots. Exogenously applied H2O2 also activated IAA-POD activity. Our results indicated that in the development of Cd toxicity syndrome the production of
ROS during IAA degradation by elevated IAA-POD activity plays a crucial role, mainly under severe Cd stress. 相似文献
46.
L’ubica Halušková Katarína Valentovičová Jana Huttová Igor Mistrík Ladislav Tamás 《Acta Physiologiae Plantarum》2010,32(1):59-65
In the present work, we investigated the alteration of oxidative and peroxidative activities of peroxidases (PODs) along the longitudinal root axis of barley seedlings during heavy metal (HM; e.g., Cd, Cu, Hg, Ni, Pb) treatment. Analysis of the individual root segments revealed that all of the analyzed HMs caused an increase of guaiacol-POD activity, however to a different extent and spatial distribution. Cd-induced ferulic acid POD activity was observed along the whole root tip (RT), while Cu and Hg caused its increase in the meristematic zone and Ni mainly at the end of the differentiation zone of RT. The activation of coniferyl alcohol POD by HMs was detected along the whole RT. HM-induced hydrogen peroxide-generating POD activity was localized mainly to the elongation zone of RT. Elevated chlorogenic acid POD activity was observed in the meristematic zone and at the end of the differentiation zone of RTs. The activation of several PODs is probably associated with enhanced H2O2 production and lignification as a defense response of roots to several HM, to prevent their uncontrolled flux. On the other hand, this defense response is accompanied by root growth inhibition, due to the enhanced rigidification of cell wall and accelerated differentiation of RTs. 相似文献
47.
Vilmos Soós Endre Sebestyén Angéla Juhász Marnie E Light Ladislav Kohout Gabriella Szalai Júlia Tandori Johannes Van Staden Ervin Balázs 《BMC plant biology》2010,10(1):236
Background
Smoke released from burning vegetation functions as an important environmental signal promoting the germination of many plant species following a fire. It not only promotes the germination of species from fire-prone habitats, but several species from non-fire-prone areas also respond, including some crops. The germination stimulatory activity can largely be attributed to the presence of a highly active butenolide compound, 3-methyl-2H-furo[2,3-c]pyran-2-one (referred to as karrikin 1 or KAR1), that has previously been isolated from plant-derived smoke. Several hypotheses have arisen regarding the molecular background of smoke and KAR1 action. 相似文献48.
Hyaluronic acid: a natural biopolymer with a broad range of biomedical and industrial applications 总被引:2,自引:0,他引:2
Hyaluronic acid (hyaluronan, HA) is a linear polysaccharide formed from disaccharide units containing N-acetyl-d-glucosamine and glucuronic acid. It has a high molecular mass, usually in the order of millions of Daltons, and interesting
viscoelastic properties influenced by its polymeric and polyelectrolyte characteristics. HA is present in almost all biological
fluids and tissues. In clinical medicine, it is used as a diagnostic marker for many diseases including cancer, rheumatoid
arthritis and liver pathologies, as well as for supplementation of impaired synovial fluid in arthritic patients by means
of intra-articular injections. It is also used in certain ophthalmological and otological surgeries and cosmetic regeneration
and reconstruction of soft tissue. Herein we present an overview of the occurrence and physiological properties of HA, as
well as of the recent advances in production biotechnology and preparation of the HA-based materials for medical application. 相似文献
49.
Katarína Ďurčeková Jana Huttová Igor Mistrík Marta Ollé Ladislav Tamás 《Plant and Soil》2007,290(1-2):61-68
The effect of Cd on H2O2 production, peroxidase (POD) activity and root hair formation were analyzed in barley root. Cd causes a strong H2O2 burst in the root region 0–6 mm behind the root tip. POD activity was activated in root tip and raised toward the root base
in Cd treated roots. In situ analyses showed that both elevated H2O2 production and POD activity are localized in the early metaxylem vascular bundles. Cd induces root hair formation in the
region 2 to 4 mm behind the root tip that was not detected in control roots. These results suggest that Cd-induced root growth
inhibition is at least partially the consequence of Cd-stimulated premature root development involving xylogenesis and root
hair formation, which is correlated with shortening of root elongation zone and therefore with root growth reduction. 相似文献
50.
Zdenko Gardian Ladislav Bumba Adam Schrofel Jana Nebesarova Frantisek Vacha 《BBA》2007,1767(6):725-731
Structure and organisation of Photosystem I and Photosystem II isolated from red alga Cyanidium caldarium was determined by electron microscopy and single particle image analysis. The overall structure of Photosystem II was found to be similar to that known from cyanobacteria. The location of additional 20 kDa (PsbQ′) extrinsic protein that forms part of the oxygen evolving complex was suggested to be in the vicinity of cytochrome c-550 (PsbV) and the 12 kDa (PsbU) protein. Photosystem I was determined as a monomeric unit consisting of PsaA/B core complex with varying amounts of antenna subunits attached. The number of these subunits was seen to be dependent on the light conditions used during cell cultivation. The role of PsaH and PsaG proteins of Photosystem I in trimerisation and antennae complexes binding is discussed. 相似文献