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951.
Plant Cell, Tissue and Organ Culture (PCTOC) - The acclimatization stress is responsible for high mortality in tissue cultured plants, which significantly reduces micropropagation efficiency. In...  相似文献   
952.
Journal of Mathematical Biology - Respiratory syncytial virus (RSV) is a leading cause of acute lower respiratory tract infection worldwide, resulting in approximately sixty thousand annual...  相似文献   
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The present article describes the synthesis and biological activity of various series of novel hydroxamic acids incorporating quinazolin‐4(3H)‐ones as novel small molecules targeting histone deacetylases. Biological evaluation showed that these hydroxamic acids were potently cytotoxic against three human cancer cell lines (SW620, colon; PC‐3, prostate; NCI?H23, lung). Most compounds displayed superior cytotoxicity than SAHA (suberoylanilide hydroxamic acid, Vorinostat) in term of cytotoxicity. Especially, N‐hydroxy‐7‐(7‐methyl‐4‐oxoquinazolin‐3(4H)‐yl)heptanamide ( 5b ) and N‐hydroxy‐7‐(6‐methyl‐4‐oxoquinazolin‐3(4H)‐yl)heptanamide ( 5c ) (IC50 values, 0.10–0.16 μm ) were found to be approximately 30‐fold more cytotoxic than SAHA (IC50 values of 3.29–3.67 μm ). N‐Hydroxy‐7‐(4‐oxoquinazolin‐3(4H)‐yl)heptanamide ( 5a ; IC50 values of 0.21–0.38 μm ) was approximately 10‐ to 15‐fold more potent than SAHA in cytotoxicity assay. These compounds also showed comparable HDAC inhibition potency with IC50 values in sub‐micromolar ranges. Molecular docking experiments indicated that most compounds, as represented by 5b and 5c , strictly bound to HDAC2 at the active binding site with binding affinities much higher than that of SAHA.  相似文献   
957.
For the first time, environmentally friendly sulfur‐rich pyramidal MnS2 synthesized via a single‐step hydrothermal process is used as a high‐performance anode material in Li‐ion and Na‐ion batteries. The superior electrochemical performance of the MnS2 electrode along with its high compatibility with ether‐based electrolytes are analyzed in both half‐ and full‐cell configurations. The reversible capacities of ≈84 mAh g?1 and ≈74 mAh g?1 at a current density of 50 mA g?1 are retained in the Li‐ion and Na‐ion full‐cells, respectively, over 200 cycles with excellent capacity retentions. Moreover, important findings regarding activation processes in the presence of a new phase transition and protective electrolyte interphase layer are revealed using ab initio density function theory calculation and in situ potentio‐electrochemical impedance spectroscopy. The detailed complex redox mechanism of MnS2 in Li/Na half‐cells is also elucidated by ex situ X‐ray photoelectron spectroscopy.  相似文献   
958.
Two isolated trunk vertebrae from the ?uppermost Albian–lower Cenomanian Kem Kem beds of Morocco are described and assigned to Lapparentophis, an early snake genus known from coeval deposits in Algeria. The Moroccan specimens represent a new species, Lapparentophis ragei, which can be distinguished from the type and only known species, Lapparentophis defrennei, by its smaller size, its more elongate vertebrae, the presence of parazygosphenal foramina, and paradiapophyses extending anteroventrally closer to the cotyle. The discovery of Lapparentophis in the Kem Kem beds adds to the relatively diverse snake assemblage previously reported from this formation and extends the geographical range of the genus. The distribution of Lapparentophis and lapparentophiid-grade (?lapparentophiid) snakes is discussed. This poorly known family of terrestrial snakes seems to be restricted to the latest Albian–early Cenomanian of North Africa, with the exception of Pouitella from the early–middle Cenomanian of France. As for many other vertebrate taxa of this period, this distribution is consistent with a dispersal event from Africa to the western part of the European archipelago.  相似文献   
959.
The detection of Listeria monocytogenes from food is currently carried out using a double enrichment. For the ISO methodology, this double enrichment is performed using half-Fraser and Fraser broths, in which the overgrowth of L. innocua can occur in samples where both species are present. In this study, we analyzed the induction of phages and phage tails of Listeria spp. in these media and in two brain heart infusion (BHI) broths (BHIM [bioMérieux] and BHIK [Biokar]) to identify putative effectors. It appears that Na2HPO4 at concentrations ranging from 1 to 40 g/liter with an initial pH of 7.5 can induce phage or phage tail production of Listeria spp., especially with 10 g/liter of Na2HPO4 and a pH of 7.5, conditions present in half-Fraser and Fraser broths. Exposure to LiCl in BHIM (18 to 21 g/liter) can also induce phage and phage tail release, but in half-Fraser and Fraser broths, the concentration of LiCl is much lower (3 g/liter). Low phage titers were induced by acriflavine and/or nalidixic acid. We also show that the production of phages and phage tails can occur in half-Fraser and Fraser broths. This study points out that induction of phages and phage tails could be triggered by compounds present in enrichment media. This could lead to a false-negative result for the detection of L. monocytogenes in food products.  相似文献   
960.
This study assessed the effectiveness of plot patterns for estimating recruit density of woody species in the dense forest of Lama Reserve (Bénin). The experimental design consisted of thirty 0.04 ha plots randomly settled in the forest and each subdivided into four hundred 1‐m² quadrats. Within each quadrat, recruits (dbh ≤10 cm) were counted and saplings (h ≥ 2 m and 2 cm ≤ dbh < 7 cm) and young trees (h ≥ 2 m and 7 cm ≤ dbh < 10 cm) were measured in dbh. In each 0.04 ha plot, seven different plot shapes and sizes were considered by grouping adjacent 1‐m2 quadrats. Relationship between mean square error of the estimation of the density of recruitments and the plot sizes was modelled using the Smith law. Results obtained showed an average value of density of recruitments of 10.7 plants/m2 with Green index value of 0.01. Shape and size of plots highly influenced the estimation of the density of recruitments. Rectangular plots of length/width = 2 and size of 72 m² (12 m × 6 m) were most efficient for the estimation of the density of recruitments in tropical dense forest with standard error of 0.79 plants/m2.  相似文献   
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