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排序方式: 共有284条查询结果,搜索用时 15 毫秒
51.
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Jossi Hillel Martien AM Groenen Michèle Tixier-Boichard Abraham B Korol Lior David Valery M Kirzhner Terry Burke Asili Barre-Dirie Richard PMA Crooijmans Kari Elo Marcus W Feldman Paul J Freidlin Asko M?ki-Tanila Marian Oortwijn Pippa Thomson Alain Vignal Klaus Wimmers Steffen Weigend 《遗传、选种与进化》2003,35(6):533-557
In a project on the biodiversity of chickens funded by the European Commission (EC), eight laboratories collaborated to assess the genetic variation within and between 52 populations from a wide range of chicken types. Twenty-two di-nucleotide microsatellite markers were used to genotype DNA pools of 50 birds from each population. The polymorphism measures for the average, the least polymorphic population (inbred C line) and the most polymorphic population (Gallus gallus spadiceus) were, respectively, as follows: number of alleles per locus, per population: 3.5, 1.3 and 5.2; average gene diversity across markers: 0.47, 0.05 and 0.64; and proportion of polymorphic markers: 0.91, 0.25 and 1.0. These were in good agreement with the breeding history of the populations. For instance, unselected populations were found to be more polymorphic than selected breeds such as layers. Thus DNA pools are effective in the preliminary assessment of genetic variation of populations and markers. Mean genetic distance indicates the extent to which a given population shares its genetic diversity with that of the whole tested gene pool and is a useful criterion for conservation of diversity. The distribution of population-specific (private) alleles and the amount of genetic variation shared among populations supports the hypothesis that the red jungle fowl is the main progenitor of the domesticated chicken. 相似文献
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Anna M Czarnecka Jerzy S Czarnecki Wojciech Kukwa Francesco Cappello Anna Ścińska Andrzej Kukwa 《Journal of biomedical science》2010,17(1):31
Mitochondria are sub-cellular organelles that produce adenosine triphosphate (ATP) through oxidative phosphorylation (OXPHOS).
As suggested over 70 years ago by Otto Warburg and recently confirmed with molecular techniques, alterations in respiratory
activity and in mitochondrial DNA (mtDNA) appear to be common features of malignant cells. Somatic mtDNA mutations have been
reported in many types of cancer cells, and some reports document the prevalence of inherited mitochondrial DNA polymorphisms
in cancer patients. Nevertheless, a careful reanalysis of methodological criteria and methodology applied in those reports
has shown that numerous papers can't be used as relevant sources of data for systematic review, meta-analysis, or finally
for establishment of clinically applicable markers. 相似文献
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Mutational analysis of a plant heat shock element 总被引:6,自引:0,他引:6
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Kamila Czarnecka Małgorzata Girek Karolina Maciejewska Robert Skibiński Jakub Jończyk Marek Bajda 《Journal of enzyme inhibition and medicinal chemistry》2018,33(1):158-170
Alzheimer’s disease (AD) is the most common progressive form of brain neurodegeneration and the most prevailing cause of dementia. Unfortunately, the aetiology of AD is not completely studied but different factors are associated with the development of AD such as among others low level of acetylcholine, aggregation of β-amyloid (Aβ), hyperphosphorylated tau protein, oxidative stress, and inflammation. The study encompass organic syntheses of 2,3-dihydro-1H-cyclopenta[b]quinoline with 5,6-dichloronicotinic acid and suitable linkers derivatives as multifunctional agents for AD treatment. Afterwards self-induced amyloid beta aggregation, inhibition studies of acetylcholinesterase and butyrylcholinesterase and molecular docking studies were performed. The results showed that 3b compound exhibited the best acetylcholinesterase inhibitory activity, with IC50 value of 0.052?µM which is lower compared to references. Besides, all synthesised compounds showed good butyrylcholinesterase inhibitory activity with IC50 values from 0.071 to 0.797?µM. Compound 3b exhibited strong Aβ1–42 aggregation inhibitory effect with 25.7% at 5?µM to 92.8% at 100?µM as well as good anti-inflammatory effect. Thus, new compounds could create new perspectives for further development as a multi-target-directed agent for AD treatment. 相似文献
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Magdalena Wypij Joanna Czarnecka Magdalena Świecimska Hanna Dahm Mahendra Rai Patrycja Golinska 《World journal of microbiology & biotechnology》2018,34(2):23
We report synthesis of silver nanoparticles (AgNPs) from Streptomyces xinghaiensis OF1 strain, which were characterised by UV–Vis and Fourier transform infrared spectroscopy, Zeta sizer, Nano tracking analyser, and Transmission electron microscopy. The antimicrobial activity of AgNPs alone, and in combination with antibiotics was evaluated against bacteria, namely Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilis, and yeasts viz., Candida albicans and Malassezia furfur by using micro-dilution method. The minimum inhibitory concentration (MIC) and minimum biocidal concentration of AgNPs against bacterial and yeast strains were determined. Synergistic effect of AgNPs in combination with antibacterial and antifungal antibiotics was determined by FIC index. In addition, MTT assay was performed to study cytotoxicity of AgNPs alone and in combination with antibiotics against mouse fibroblasts and HeLa cell line. Biogenic AgNPs were stable, spherical, small, polydispersed and capped with organic compounds. The variable antimicrobial activity of AgNPs was observed against tested bacteria and yeasts. The lowest MIC (16 µg ml?1) of AgNPs was found against P. aeruginosa, followed by C. albicans and M. furfur (both 32 µg ml?1), B. subtilis and E. coli (both 64 µg ml?1), and then S. aureus and Klebsiella pneumoniae (256 µg ml?1). The high synergistic effect of antibiotics in combination with AgNPs against tested strains was found. The in vitro cytotoxicity of AgNPs against mouse fibroblasts and cancer HeLa cell lines revealed a dose dependent potential. The IC50 value of AgNPs was found in concentrations of 4 and 3.8 µg ml?1, respectively. Combination of AgNPs and antibiotics significantly decreased concentrations of both antimicrobials used and retained their high antibacterial and antifungal activity. The synthesis of AgNPs using S. xinghaiensis OF1 strain is an eco-friendly, cheap and nontoxic method. The antimicrobial activity of AgNPs could result from their small size. Remarkable synergistic effect of antibiotics and AgNPs offer their valuable potential in nanomedicine for clinical application as a combined therapy in the future. 相似文献
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Assessing population density is crucial for studying the ecology and evolutionary biology of species as well as for conservation purposes. Here we used point count methods to infer population density in a single-island endemic passerine bird, the Réunion Grey White-eye Zosterops borbonicus, that displays striking evidence of differentiation at a small spatial scale. Population density was estimated at 5.17 birds ha?1 (CL 4.85–5.50), a value somewhat higher than previously believed. This estimation provides the first detailed estimation of bird population density in the vulnerable summit ecosystems of Réunion and will possibly allow a better understanding of the evolutionary causes of this plumage colour variation. 相似文献