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31.
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The myogenic behaviour of primary human muscle precursor cells (MPCs) obtained from young (aged 20–25 years) and elderly people (aged 67–82 years) was studied in culture. Cells were compared in terms of proliferation, DNA damage, time course and extent of myogenic marker expression during differentiation, fusion, size of the formed myotubes, secretion of the myogenic regulatory cytokine TGF‐β1 and sensitivity to TGF‐β1 treatment. No differences were observed between cells obtained from the young and elderly people. The cell populations were expanded in culture until replicative senescence. Cultures that maintained their initial proportion of myogenic cells (desmin positive) with passaging (n = 5) were studied and compared with cells from the same individuals in the non‐senescent state. The senescent cells exhibited a greater number of cells with DNA damage (γ‐H2AX positive), showed impaired expression of markers of differentiation, fused less well, formed smaller myotubes and secreted more TGF‐β. The data strongly suggest that MPCs from young and elderly people have similar myogenic behaviour.  相似文献   
33.
Abstract

3′-Oxa-4′-thiocytidine nucleoside analogues 14–17 were prepared from oxathiolanes 10 and 11, and evaluated for activity against HIV-1 and HBV in vitro. The nucleoside analogues were found to possess potent activities against HIV-1 in a panel of cell lines. Compound 16 is moderately active against HBV in 2.2.15 cells.  相似文献   
34.
Abstract

A series of different novel nonclassical nucleosides have been synthesised and evaluated for their inhibitory activity against human immunodeficiency virus (HIV) replication in MT-4 cells.  相似文献   
35.
Abstract

The 6-β-arylvinyl-2- and 4-glucosyl-3-thioxo-2,3-dihydro-1,2,4-triazin-5(4H)-ones were synthesized with high selectivity using the recently developed amino protecting group strategy. The structure of these new glucosides was established chemically and spectroscopically. Also, some interesting chemical transformations and rearrangements were observed.  相似文献   
36.
Chemical investigations of the soft coral Sarcophyton trocheliophorum, has led to the isolation of six cembranoids, two of which are new, Trochelioid A (1) and B (2), and one, 16-oxosarcophytonin E (3) isolated from nature for the first time. Additionally, two have been isolated from S. trocheliophorum for the first time (4 and 6). Structures were elucidated by employing extensive NMR and HR-FAB-MS experimentation.  相似文献   
37.
Plant and Soil - Phytoextraction is an in situ technique that can be applied to minerals and mining wastes using hyperaccumulator plants to purposely bio-concentrate high levels of metals or...  相似文献   
38.
39.
This work was based on field screening procedure to detect the population density of Aphis craccivora for two successive seasons (2004–2005) and (2005–2006) to emphasis the relation between the economic injury level (EIL) and yield loss.

Results obtained showed that the equilibrium position (steady point) during the first and second season was 9.06 and 3.32 individuals/five leaflets, respectively, while the injury level was 3.4 and 1.16 individuals/leaflets. When the bean plant was subjected to three successive insecticidal applications during the early growing, season is sufficient to decrease the yield loss significantly (yield capacity 21.43 Ard./fed.) with comparing to untreated plant (14.98 Ard./fed.), while the plants exposure for one treatment was 17.36 Ard./fed. The EIL was 8.6 individual of aphids/plant depending on the market price of bean and control cost during the season.  相似文献   
40.
The molecular phylogeny of the genus Odontobuthus Vachon, 1950 (Scorpiones: Buthidae) in Iran was evaluated using two mitochondrial DNA genes, cytochrome c oxidase, subunit I (COI) and 16S ribosomal RNA (16S rRNA). The molecular phylogenetic analyses were performed using Maximum Parsimony, Maximum Likelihood and Bayesian inference methods. The resulting topologies supported two main clades: the clade comprising Odontobuthus doriae, O. bidentatus, and O. tavighiae, and another one which is the O. tirgari clade. The results clearly presented additional support for the taxonomic validity of the recently described species, O. tirgari and O. tavighiae. In addition, the monophyly of two previously described species O. doriae and O. bidentatus was confirmed. According to the data presented here, three taxonomically valid species belonging to the genus Odontobuthus occur in Iran.  相似文献   
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