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91.
Summary. Fritillaria karelinii Fisch. ex D.Don ( Liliaceae ) is illustrated. Its relationships with other species and the position of subgenus Rhinopetalum are discussed. Instructions for its cultivation are given. 相似文献
92.
93.
Quantitative proteomic analysis of cabernet sauvignon grape cells exposed to thermal stresses reveals alterations in sugar and phenylpropanoid metabolism 下载免费PDF全文
Grapes (Vitis vinifera) are a valuable fruit crop and wine production is a major industry. Global warming and expanded range of cultivation will expose grapes to more temperature stresses in future. Our study investigated protein level responses to abiotic stresses, with particular reference to proteomic changes induced by the impact of four different temperature stress regimes, including both hot and cold temperatures, on cultured grape cells. Cabernet Sauvignon cell suspension cultures grown at 26°C were subjected to 14 h of exposure to 34 and 42°C for heat stress, and 18 and 10°C for cold stress. Cells from the five temperatures were harvested in biological triplicates and label‐free quantitative shotgun proteomic analysis was performed. A total of 2042 non‐redundant proteins were identified from the five temperature points. Fifty‐five proteins were only detected in extreme heat stress conditions (42°C) and 53 proteins were only detected at extreme cold stress conditions (10°C). Gene Ontology (GO) annotations of differentially expressed proteins provided insights into the metabolic pathways that are involved in temperature stress in grape cells. Sugar metabolism displayed switching between alternative and classical pathways during temperature stresses. Additionally, nine proteins involved in the phenylpropanoid pathway were greatly increased in abundance at extreme cold stress, and were thus found to be cold‐responsive proteins. All MS data have been deposited in the ProteomeXchange with identifier PXD000977 ( http://proteomecentral.proteomexchange.org/dataset/PXD000977 ). 相似文献
94.
Ashraf Ul Kabir Mehdi Bin Samad Arif Ahmed Mohammad Rajib Jahan Farjana Akhter Jinat Tasnim S. M. Nageeb Hasan Sania Sarker Sayfe J. M. A. Hannan 《PloS one》2015,10(2)
BackgroundThe study was designed to investigate the probable mechanisms of anti-hyperglycemic activity of B. Vulgaris.ConclusionFindings of the present study clearly prove the role of Acetylcholine and GLP-1 in the Insulin secreting activity of B. Vulgaris. Increased glucose uptake in the skeletal muscles and subsequent glycogen synthesis may also play a part in the anti-hyperglycemic activity of B. Vulgaris. 相似文献
95.
Farshad Shadanloo Mohammad Hasan Najafi Sayed Morteza Hosseini Mehdi Hajian Mohsen Forouzanfar Kamran Ghaedi Parvaneh Abedi Somaye Ostadhosseini Laleh Hosseini Morad‐Pasha Eskandari‐Nasab Mohammad Hossein Nasr Esfahani 《Molecular reproduction and development》2010,77(10):868-875
In relation to the growing recent interest in the establishment of sperm‐mediated gene transfer (SMGT) technology as a convenient and effective method for the simple production of transgenic animals, in this study the possibility of using SMGT to produce transgenic caprine embryos was investigated for the first time. Buck sperm were directly incubated with different concentrations (0–500 ng) of pcDNA/his/Lac‐Z plasmid and used for IVF or ICSI. Sperm used for ICSI were categorized into motile or live‐immotile group before being injected into oocytes. In a separate experiment, dead sperm prepared by repeated freezing/thawing were used for DNA‐incubation before ICSI. Sham injection was carried out by intracytoplasmic injection of approximately the same volume of media containing different doses of DNA using an ICSI needle. Transgene expression and transmission were detected by X‐Gal staining and PCR analysis of developed embryos, respectively. A reasonable blastocyst rate was observed in all the groups. Only embryos in the sham group were negative for transgene transmission. Transgene expression was completely dependent on the delivery technique and status of sperm, and was only observed in the live‐immotile and dead ICSI groups. The results of this study showed that the technique (IVF vs. ICSI vs. sham injection), sperm status (motile vs. live‐immotile vs. dead) and to some extent DNA concentration affect embryo development, transgene transmission and expression. Mol. Reprod. Dev. 77:868–875, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
96.
Talbi C Lemey P Suchard MA Abdelatif E Elharrak M Nourlil J Jalal N Faouzi A Echevarría JE Vazquez Morón S Rambaut A Campiz N Tatem AJ Holmes EC Bourhy H 《PLoS pathogens》2010,6(10):e1001166
Understanding the role of humans in the dispersal of predominantly animal pathogens is essential for their control. We used newly developed Bayesian phylogeographic methods to unravel the dynamics and determinants of the spread of dog rabies virus (RABV) in North Africa. Each of the countries studied exhibited largely disconnected spatial dynamics with major geopolitical boundaries acting as barriers to gene flow. Road distances proved to be better predictors of the movement of dog RABV than accessibility or raw geographical distance, with occasional long distance and rapid spread within each of these countries. Using simulations that bridge phylodynamics and spatial epidemiology, we demonstrate that the contemporary viral distribution extends beyond that expected for RABV transmission in African dog populations. These results are strongly supportive of human-mediated dispersal, and demonstrate how an integrated phylogeographic approach will turn viral genetic data into a powerful asset for characterizing, predicting, and potentially controlling the spatial spread of pathogens. 相似文献
97.
Sabine Cohen Lars P. Jordheim Mehdi Megherbi Charles Dumontet Jérôme Guitton 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(22):1912-1928
Endogenous ribonucleotides and deoxyribonucleotides play a crucial role in cell function. The determination of their levels is of fundamental interest in numerous applications such as energy metabolism, biochemical processes, or in understanding the mechanism of nucleoside analog compounds. Nucleoside analogs are widely used in anticancer therapy. Their mechanisms of action are related to their structural similarity with natural nucleotides. Numerous assays have been described for the determination of endogenous nucleotides or anticancer nucleotide analogs in different matrices such as cellular cultures, tissue or peripheral blood mononuclear cells. The determination of these compounds is challenging due to the large difference of concentrations between ribonucleotides and deoxyribonucleotides, the presence of numerous endogenous interferences in complex matrices and the high polarity of the molecules due to the phosphate moiety. The extraction was generally performed at low temperature and was based on protein precipitation using acid or solvent mixture. This first phase could be coupled with extraction or cleaning step of the supernatant. Liquid chromatography coupled with UV detection and based on ion-exchange chromatography using non-volatile high salt concentrations was largely described for the quantification of nucleotides. However, the development of LC–MS and LC–MS/MS during the last ten years has constituted a sensitive and specific tool. In this case, analytical column was mostly constituted by graphite or C18 stationary phase. Mobile phase was usually based on a mixture of ammonium buffer and acetonitrile and in several assays included a volatile ion-pairing agent. Mass spectrometry detection was performed either with positive or negative electrospray mode according to compounds and mobile phase components. The purpose of the current review is to provide an overview of the most recent chromatographic assays (over the past ten years) developed for the determination of endogenous nucleotides and nucleotide analogs used in cancer therapy. We focused on sample preparation, chromatographic separation and quantitative considerations. 相似文献
98.
Background
It has been understood that biological networks have modular organizations which are the sources of their observed complexity. Analysis of networks and motifs has shown that two types of hubs, party hubs and date hubs, are responsible for this complexity. Party hubs are local coordinators because of their high co-expressions with their partners, whereas date hubs display low co-expressions and are assumed as global connectors. However there is no mutual agreement on these concepts in related literature with different studies reporting their results on different data sets. We investigated whether there is a relation between the biological features of Saccharomyces Cerevisiae 's proteins and their roles as non-hubs, intermediately connected, party hubs, and date hubs. We propose a classifier that separates these four classes. 相似文献99.