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排序方式: 共有338条查询结果,搜索用时 15 毫秒
1.
Daw-Yang Hwang Stefan Kohl Xueping Fan Asaf Vivante Stefanie Chan Gabriel C. Dworschak Julian Schulz Albertien M. van Eerde Alina C. Hilger Heon Yung Gee Tracie Pennimpede Bernhard G. Herrmann Glenn van de Hoek Kirsten Y. Renkema Christoph Schell Tobias B. Huber Heiko M. Reutter Neveen A. Soliman Natasa Stajic Radovan Bogdanovic Elijah O. Kehinde Richard P. Lifton Velibor Tasic Weining Lu Friedhelm Hildebrandt 《Human genetics》2015,134(8):905-916
2.
Francisco Valera Radovan Vclav Miguel ngel Calero‐Torralbo Teresa Martínez Jesús Veiga 《Restoration Ecology》2019,27(1):220-227
Nest box supplementation is widely used to increase nest‐site availability for cavity nesting animals but the analysis of its effects on individuals breeding in natural cavities is often neglected. This study offers a novel restoration technique to revert abandonment of natural breeding sites by a secondary cavity avian bird, the European roller (Coracias garrulus), and other ecologically similar species. We found that, after a program of nest box supplementation with ensuing monitoring, rollers gradually abandon nesting in natural and seminatural cavities in favor of nest boxes because the latter are of higher quality. We examine whether reducing the entrance size of natural and seminatural cavities improves their suitability for rollers. A 6‐year program reduced the diameter of the entrance of sandstone cavities and cavities in bridges. This led to a high occupancy (59%) of manipulated nest‐sites. Manipulated sites were most frequently occupied by rollers and little owls (Athene noctua) (31 and 18% of sites, respectively). Manipulation did not affect clutch size or fledgling success. We suggest that nest‐site diversity and nesting in natural cavities should be preserved to reduce nest box dependence. Our study illustrates the value of nest boxes when used alongside restoration of natural breeding sites and provides insights for the management of natural cavities. 相似文献
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5.
Chester Bittencourt Sacramento Vanessa Dionisio Cantagalli Mariana Grings Leonardo Pinto Carvalho José Carlos Costa Baptista‐Silva Abram Beutel Cassia Toledo Bergamaschi Ruy Ribeiro de Campos Junior Jane Zveiter de Moraes Christina Maeda Takiya Vívian Yochiko Samoto Radovan Borojevic Flavia Helena da Silva Nance Beyer Nardi Hans Fernando Dohmann Hamilton Silva Junior Valderez Bastos Valero Sang Won Han 《The journal of gene medicine》2009,11(4):345-353
6.
Radovan Murín Ghasem Mohammadi Dieter Leibfritz Bernd Hamprecht 《Neurochemical research》2009,34(7):1195-1203
The three essential amino acids, valine, leucine and isoleucine, constitute the group of branched-chain amino acids (BCAAs).
BCAAs are rapidly taken up into the brain parenchyma, where they serve several distinct functions including that as fuel material
in brain energy metabolism. As one function of astrocytes is considered the production of fuel molecules that support the
energy metabolism of adjacent neural cells in brain. Astroglia-rich primary cultures (APC) were shown to rapidly dispose of
the BCAAs, including valine, contained in the culture medium. While the metabolisms of leucine and isoleucine by APC have
already been studied in detail, some aspects of valine metabolism remained to be determined. Therefore, in the present study
an NMR analysis was performed to identify the 13C-labelled metabolites that are generated by APC during catabolism of [U-13C]valine and that are subsequently released into the incubation medium. The results presented show that APC (1) are potently
disposing of the valine contained in the incubation medium; (2) are capable of degrading valine to the tricarboxylic acid
(TCA) cycle member succinyl-CoA; and (3) release into the extracellular milieu valine catabolites and compounds generated
from them such as [U-13C]2-oxoisovalerate, [U-13C]3-hydroxyisobutyrate, [U-13C]2-methylmalonate, [U-13C]isobutyrate, and [U-13C]propionate as well as several TCA cycle-dependent metabolites including lactate.
This article is dedicated to Dr. George DeVries. 相似文献
7.
Limonium failachicum, a new diploid (2n=18) species ofPlumbaginaceae, is described from Arabia. The species is taxonomically related toL. iranicum andL. carnosum. The new taxon is so far the only known endemic species for the State of Kuwait. Ecology and distribution of the new species is briefly discussed. 相似文献
8.
Non-invasive fetal RHD and RHCE genotyping using real-time PCR testing of maternal plasma in RhD-negative pregnancies. 总被引:2,自引:0,他引:2
Ilona Hromadnikova Lenka Vechetova Klara Vesela Blanka Benesova Jindrich Doucha Radovan Vlk 《The journal of histochemistry and cytochemistry》2005,53(3):301-305
We assessed the feasibility of fetal RHD and RHCE genotyping by analysis of DNA extracted from plasma samples of RhD-negative pregnant women using real-time PCR and primers and probes targeted toward RHD and RHCE genes. We analyzed 45 pregnant women in the 11th to 40th weeks of pregnancy and correlated the results with serological analysis of cord blood after delivery. Non-invasive prenatal fetal RHD exon 7, RHD exon 10, RHCE exon 2 (C allele), and RHCE exon 5 (E allele) genotyping analysis of maternal plasma samples was correctly performed in 45 out of 45 RhD-negative pregnant women delivering 24 RhD-, 17 RhC-, and 7 RhE-positive newborns. Detection of fetal RHD and the C and E alleles of RHCE gene from maternal plasma is highly accurate and enables implementation into clinical routine. We recommend performing fetal RHD and RHCE genotyping together with fetal sex determination in alloimmunized D-negative pregnancies at risk of hemolytic disease of the newborn. In case of D-negative fetus, amplification of another paternally inherited allele (SRY and/or RhC and/or RhE positivity) proves the presence of fetal DNA in maternal circulation. 相似文献
9.
Radovan Smolinský Lumír Gvoždík 《Biological journal of the Linnean Society. Linnean Society of London》2013,108(1):109-115
Many organisms respond to the heterogeneity of abiotic environmental conditions by plastic modifications of their phenotypes (acclimation or acclimatization). Despite considerable research efforts in this area, the beneficial (adaptive) effect of acclimation or acclimatization is still debated. We examined whether the development of newt larvae (Ichthyosaura alpestris) under different natural light and thermal conditions subsequently altered their susceptibility to predation in sun‐exposed versus shaded tanks in nature. During predation trials in various light and temperature conditions, newt larvae that developed in sun‐exposed warmer tanks consistently suffered from higher predation by dragonfly nymphs (Aeshna cyanea) compared to larvae from shaded or colder tanks. We conclude that higher sun exposure during embryonic and larval development negatively affects antipredator performance even in sun‐exposed tanks: this result is inconsistent with the beneficial acclimation hypothesis. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ●● , ●●–●●. 相似文献
10.
Gabriela Seydlová Radovan Fišer Radomír Čabala Petr Kozlík Jaroslava Svobodová Miroslav Pátek 《生物化学与生物物理学报:生物膜》2013
Surfactin is a cyclic lipopeptide antibiotic that disturbs the integrity of the cytoplasmic membrane. In this study, the role of membrane lipids in the adaptation and possible surfactin tolerance of the surfactin producer Bacillus subtilis ATCC 21332 was investigated. During a 1-day cultivation, the phospholipids of the cell membrane were analyzed at the selected time points, which covered both the early and late stationary phases of growth, when surfactin concentration in the medium gradually rose from 2 to 84 μmol·l− 1. During this time period, the phospholipid composition of the surfactin producer's membrane (Sf+) was compared to that of its non-producing mutant (Sf−). Substantial modifications of the polar head group region in response to the presence of surfactin were found, while the fatty acid content remained unaffected. Simultaneously with surfactin production, a progressive accumulation up to 22% of the stress phospholipid cardiolipin was determined in the Sf+ membrane, whereas the proportion of phosphatidylethanolamine remained constant. At 24 h, cardiolipin was found to be the second major phospholipid of the membrane. In parallel, the Laurdan generalized polarization reported an increasing rigidity of the lipid bilayer. We concluded that an enhanced level of cardiolipin is responsible for the membrane rigidification that hinders the fluidizing effect of surfactin. At the same time cardiolipin, due to its negative charge, may also prevent the surfactin-membrane interaction or surfactin pore formation activity. 相似文献