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951.
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
952.
David Gela Martin Kocour Martin Flajšhans Otomar Linhart Marek Rodina 《Reviews in Fish Biology and Fisheries》2010,20(3):301-306
A triennial performance test of five groups of tench, Tinca tinca (L.): Vodnany induced triploid V3n, Vodnany meiotic gynogenic Vgyn, diploid Vodnany V2n, Hungarian H2n and German G2n) in pond
monoculture was carried out with diploid golden tench as control (C) to compute corrected weight of the groups tested. Survival
rate ranged from 11.6% (V2n) to 30.6% (Vgyn) in yearlings, from 71.2% (V2n) to 91.5% (H2n) in 2 year-olds, from 60.0% (Vgyn)
to 75.7% (V2n) in 3 year-olds while that of the control group was 8.5, 38.3 and 40.2% in the respective seasons. After three
growing seasons the corrected weight of the fish in the groups H2n (254.6bg), V3n (257.0cg) and G2n (371.4cg) was higher (P < 0.05, Tukey HSD test) than that from the C (183.3ag) and V2n(205.6abg) groups. Among the chromosomally manipulated groups, ANCOVA test found the least slaughtering value for Vgyn (84.3%); among
the purebreds the highest value was found for H2n (87.32%), significantly differing from V2n and G2n strains. A high gonadosomatic
index in females (2.94 vs. 0.44% in males) resulted in inferior slaughtering values. 相似文献
953.
Martin Flajšhans David Gela Martin Kocour Hana Buchtová Marek Rodina Martin Pšenička Vojtěch Kašpar Veronika Piačková Eliška Sudová Otomar Linhart 《Reviews in Fish Biology and Fisheries》2010,20(3):317-329
Performance and physiological traits and health of spontaneous and induced triploid tench are reviewed. Triploidy is best
induced with cold shock; with triploids exhibiting 13.5–51.5% better weight gain, 2.69–3.94% higher slaughtering value, 20–60%
lower gonadosomatic index, 0.9–4.5% higher dry matter in flesh and up to 107% more flesh fat than diploids, if farmed untill
post sexual maturity. Triploids exhibit more abdominal fat and less polyunsaturated fatty acids of the n-3 and n-6 groups
in the flesh. Triploid females are sterile, while triploid males may produce aneuploid spermatozoa with varying DNA content
(1–1.9n) which may initiate development of embryos. Triploids have milder seasonal dynamics in their erythrocyte profile than
the diploids. Thinner diffusion distance in gills of triploids than in diploids is interpreted as adaptation to lower aerobic
capacity. Triploids show neither stronger tendencies to anatomic malformations, nor have bigger affinity to parasitic diseases
than the diploids. Production of triploid tench could be an economically interesting method of farming to higher marketable
weight, bringing a relatively high product quality. 相似文献
954.
Olivier Corminboeuf Olivier Bezençon Corinna Grisostomi Ľuboš Remeň Sylvia Richard-Bildstein Daniel Bur Lars Prade Patrick Hess Panja Strickner Walter Fischli Beat Steiner Alexander Treiber 《Bioorganic & medicinal chemistry letters》2010,20(21):6286-6290
The discovery of a new series of piperidine-based renin inhibitors is described herein. SAR optimization upon the P3 renin sub-pocket is described, leading to the discovery of 9 and 41, two bioavailable renin inhibitors orally active at low doses in a transgenic rat model of hypertension. 相似文献
955.
Petr Kočalka Dominik Rejman Václav Vaněk Markéta Rinnová Ivana Tomečková Šárka Králíková Magdalena Petrová Ondřej Páv Radek Pohl Miloš Buděšínský Radek Liboska Zdeněk Točík Natalya Panova Ivan Votruba Ivan Rosenberg 《Bioorganic & medicinal chemistry letters》2010,20(3):862-865
Structurally diverse, sugar-modified, thymine-containing nucleoside phosphonic acids were evaluated for their ability to inhibit thymidine phosphorylase (TP, EC 2.4.2.4) purified from spontaneous T-cell lymphomas of an inbred Sprague-Dawley rat strain. From a large set of tested compounds, among them a number of pyrrolidine-based derivatives, 10 nucleotide analogues with IC50 values below 1 μM were selected. Out of them, four compounds strongly inhibited the enzyme with IC50 values lying in a range of 11–45 nM. These most potent compounds might be bi-substrate analogues. 相似文献
956.
957.
Senka S. Vidović Ibrahim O. Mujić Zoran P. Zeković Žika D. Lepojević Vesna T. Tumbas Aida I. Mujić 《Food biophysics》2010,5(1):49-58
Considering the growing interest for mushrooms and the demand search of natural antioxidants sources, the aim of this study
was to investigate the antioxidant properties of two edible widely used Boletus species, Boletus edulis, and Boletus auranticus, collected from Istra region in Croatia in late summer 2007. To evaluate the antioxidant properties and content of antioxidant
compounds, scavenging capacity on DPPH˙, OH˙, and O2˙− radicals, reducing power and capacity to inhibit lipid peroxidation has been investigated. It is determined that content
of total phenols (41.82 ± 0.08 mg gallic acid equivalent per gram of dry extract) was higher for B. edulis. Using high performance liquid chromatography/diode array detector analysis, the main antioxidant compound, variegatic acid,
has been detected and quantified. 1,1-Diphenyl-2-picryl-hydrazyl-hydrate assay was used as a preliminary free radical–scavenging
evaluation. By this assay, it has been found that B. edulis dry mushroom extract exhibits 50% of inhibition value at the extract concentration of 0.016 ± 0.0003 mg/ml. The extracts
were capable of reducing iron(III) and, thus, are capable of donating electrons. Using electron paramagnetic resonance spin-trapping
and spin-probing techniques, activity against relevant reactive species, ˙OH and O2˙− radical, was analyzed for both mushroom extracts. Both investigated extracts are determined as good inhibitors for ˙OH radical
reduction, and both exhibited significant capacity for scavenging O2˙− radical and for that could help to prevent or meliorate oxidative damage. Only B. edulis extract prevents lipid peroxidation. Investigated mushroom extracts could represent easily accessible natural antioxidant
resource. 相似文献
958.
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
959.
Salix spp. nectar honey volatiles of Croatian origin were analyzed by headspace solid‐phase microextraction (HS‐SPME) and ultrasonic solvent extraction (USE), followed by gas chromatography and mass spectrometry (GC, GC/MS). Isolated volatiles were found in the honey headspace and extracts with almost exclusive distribution of several abundant compounds (e.g., phenylacetic acid, pinocembrin, 8‐hydroxy‐4,7‐dimethylcoumarin, and 3‐hydroxy‐trans‐β‐damascone in the extracts, or safranal and lilac alcohols in the headspace). Comparison with Croatian Salix spp. honeydew honey revealed similarities regarding distribution of important shikimate pathway derivatives (e.g., high percentage of phenylacetic acid) and several norisoprenoids (α‐isophorone and 4‐oxoisophorone). On the other hand, distinct features of this honey were occurrence of compounds such as pinocembrin, 8‐hydroxy‐4,7‐dimethylcoumarin, phenylacetonitrile, norisoprenoids (major ones: 3‐hydroxy‐trans‐β‐damascenone and trans‐β‐damascone), more pronounced variability of linalool‐derived compounds, as well as the abundance of 3‐methylpropanoic acid, 3‐methylbutanoic acid, 2‐methylpentanoic acid, and 3‐methylpentan‐1‐ol. 相似文献
960.
Srđan Đ. Stojanović Božidarka L. Zarić Snežana D. Zarić 《Journal of molecular modeling》2010,16(11):1743-1751
The distinguishing property of Sm protein associations is very high stability. In order to understand this property, we analyzed
the interfaces and compared the properties of Sm protein interfaces with those of a test set, the Binding Interface Database
(BID). The comparison revealed that the main differences between the interfaces of Sm proteins and those of the BID set are
the content of charged residues, the coordination numbers of the residues, knowledge-based pair potentials, and the conservation
scores of hot spots. In Sm proteins, the interfaces have more hydrophobic and fewer charged residues than the surfaces, which
is also the case for the BID test set and other proteins. However, in the interfaces, the content of charged residues in Sm
proteins (26%) is substantially larger than that in the BID set (22%). Hot spots are residues that make up a small fraction
of the interfaces, but they contribute most of the binding energy. These residues are critical to protein–protein interactions.
Analyses of knowledge-based pair potentials of hot spot and non-hot spot residues in Sm proteins show that they are significantly
different; their mean values are 31.5 and 11.3, respectively. In the BID set, this difference is smaller; in this case, the
mean values for hot spot and non-hot spot residues are 20.7 and 12.4, respectively. Hence, the pair potentials of hot spots
differ significantly for the Sm and BID data sets. In the interfaces of Sm proteins, the amino acids are tightly packed, and
the coordination numbers are larger in Sm proteins than in the BID set for both hot spots and non-hot spots. At the same time,
the coordination numbers are higher for hot spots; the average coordination number of the hot spot residues in Sm proteins
is 7.7, while it is 6.1 for the non-hot spot residues. The difference in the calculated average conservation score for hot
spots and non-hot spots in Sm proteins is significantly larger than it is in the BID set. In Sm proteins, the average conservation
score for the hot spots is 7.4. Hot spots are surrounded by residues that are moderately conserved (5.9). The average conservation
score for the other interface residues is 5.6. The conservation scores in the BID set do not show a significant distinction
between hot and non-hot spots: the mean values for hot and non-hot spot residues are 5.5 and 5.2, respectively. These data
show that structurally conserved residues and hot spots are significantly correlated in Sm proteins. 相似文献