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Fluorene‐based boronic acids as fluorescent chemosensor for monosaccharides at physiological pH
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Two fluorene‐based boronic acids, 9,9‐dimethyl‐9H‐fluoren‐2‐yl‐2‐boronic acid (1) and 9,9‐dimethyl‐9H‐fluoren‐2,7‐diyl‐2,7‐diboronic acid (2), were synthesized and their sensing abilities for detection of D ‐monosaccharides were investigated by fluorescence at physiological pH. It was found that both boronic acids 1 and 2 have high selectivity and sensitivity for D ‐fructose with stability constant of 47.2 and 412.9, respectively. The sensor 2 showed a linear response toward D ‐fructose in the concentration range from 5 × 10–5 to 10–1 mol L–1 with the detection limit of 2 × 10–5 mol L–1. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Hamed Yousefzadeh Abasalt Hosseinzadeh Colagar Fatemeh Akbarzadeh Nicholas P. Tippery 《Tree Genetics & Genomes》2014,10(6):1611-1629
The taxonomy and phylogenetic relationships among Castanea species were investigated using sequence data from the chloroplast trnL-F and trnH-psbA intergenic spacer regions. Samples included Castanea specimens of uncertain taxonomic affinity that were collected in the Hyrcanian forest of northern Iran. The trnL-F data were more informative than trnH-psbA, having seven parsimony-informative sites. A low level of haplotype diversity was detected within Hyrcanian samples and the whole species of the genus Castanea. In the trnL-F dataset, Castanea sativa and Castanea mollissima have unique character states that differentiate them from other species of Castanea. The genus Castanea was recovered as a monophyletic with high to moderate support when inferred from combined trnH-psbA and trnL-F spacer data. Two main lineages received minimal support in the trnL-F analysis, whereas trnH-psbA could not distinguish different species of Castanea from each other. Finally, low levels of haplotype diversity was found within small remnant stands of Castanea in the Hyrcanian forest, indicating that genetic erosion may increase the extinction risk for these valuable trees. 相似文献
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Asgharian H Sahafi HH Ardalan AA Shekarriz S Elahi E 《Molecular ecology resources》2011,11(3):461-472
We provide cytochrome c oxidase subunit 1 (COI) barcode sequences of fishes of the Nayband National Park, Persian Gulf, Iran. Industrial activities, ecological considerations and goals of The Fish Barcode of Life campaign make it crucial that fish species residing in the park be identified. To the best of our knowledge, this is the first report of barcoding data on fishes of the Persian Gulf. We examined 187 individuals representing 76 species, 56 genera and 32 families. The data flagged potentially cryptic species of Gerres filamentosus and Plectorhinchus schotaf. 16S rDNA data on these species are provided. Exclusion of these two potential cryptic species resulted in a mean COI intraspecific distance of 0.18%, and a mean inter- to intraspecific divergence ratio of 66.7. There was no overlap between maximum Kimura 2-parameter distances among conspecifics (1.66%) and minimum distance among congeneric species (6.19%). Barcodes shared among species were not observed. Neighbour-joining analysis showed that most species formed cohesive sequence units with little variation. Finally, the comparison of 16 selected species from this study with meta-data of conspecifics from Australia, India, China and South Africa revealed high interregion divergences and potential existence of six cryptic species. Pairwise interregional comparisons were more informative than global divergence assessments with regard to detection of cryptic variation. Our analysis exemplifies optimal use of the expanding barcode data now becoming available. 相似文献
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Hasan Hosseinzadeh Saeid Nasrollanejad Hadi Khateri 《Archives Of Phytopathology And Plant Protection》2013,46(16):1884-1890
Plant virus diseases cause major losses in agricultural and horticultural products, especially in tropical and subtropical regions. The first step to manage these diseases is detecting, identifying and determining the pathogen characteristics. Cucumber mosaic disease is one of the most prevalent and damaging plant diseases in the world which is caused by Cucumber mosaic virus (CMV). Each year, this virus causes yield decreasing and substantial economic damages in its host plants worldwide including the north of Iran. In order to study and identify CMV, 935 leaf samples were collected based on typical symptoms from 10 crops (tomato, pea, tobacco, soybean, watermelon, broad bean, squash, cucumber, eggplant and lettuce) in different regions of Golestan and Mazandaran provinces (north of Iran) during 2009–2010. Suspicious samples were analysed by DAS-ELISA and polyclonal antibodies. The results showed that 275 samples (29.4%) were infected by CMV. Between these hosts, the highest and the lowest CMV infection was associated to watermelon (62.44%) and lettuce (0%), respectively. Among sampling locations, Behshahr (100%) and Minoodasht (3.47%) showed the maximum and minimum infection, respectively. 相似文献
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Fourier transform infrared (FTIR) microspectroscopy can be considered to be a fast and non-invasive tool for distinguishing
between normal and cancerous cells and tissues without the need for laborious and invasive sampling procedures. Gastric samples
from four patients (age, 65±2 years) were analysed. Samples were obtained from the organs removed during gastrectomy and then
classified as normal or cancerous. Classification was based on histopathological examinations at our institution. Formalin-fixed
sections of gastric tissue were analysed by FTIR- microspectroscopy. To characterize differences between sections of normal
and cancerous tissue, specific regions of the spectra were analysed to study variations in the levels of metabolites. To distinguish
between two conditions (normal and cancerous), changes in the relative intensity of bands in the range 600–4000 cm−1 were analysed. A FTIR spectral map of the bands in the region 2800–3100 cm–1 and 900–1800 cm–1 were created to analyse pathological changes in tissues. The limited data available showed that normal gastric tissue had
stronger absorption than cancerous tissue over a wide region in the four patients. There was a significant decrease in total
biomolecular components for cancerous tissue compared with normal tissue. 相似文献
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Hossein Hosseinzadeh Siavash Parvardeh Marjan Nassiri Asl Hamid R. Sadeghnia Toktam Ziaee 《Phytomedicine》2007,14(9):621-627
It has been previously reported that Nigella sativa oil (NSO) and thymoquinone (TQ), active constituent of N. sativa seeds oil, may prevent oxidative injury in various models. Therefore, we considered the possible effect of TQ and NSO on lipid peroxidation level following cerebral ischemia-reperfusion injury (IRI) in rat hippocampus. Male NMRI rats were divided into nine groups, namely, sham, control, ischemia and ischemia treated with NSO or TQ. TQ (2.5, 5 and 10 mg/kg), NSO (0.048, 0.192 and 0.384 mg/kg), phenytoin (50 mg/kg, as positive control) and saline (10 ml/kg, as negative control) were injected intraperitoneally immediately after reperfusion and the administration was continued every 24h for 72 h after induction of ischemia. The transient global cerebral ischemia was induced using four-vessel-occlusion method for 20 min. Lipid peroxidation level in hippocampus portion was measured as malondialdehyde (MDA) based on its reaction with thiobarbituric acid (TBA) following ischemic insult. The transient global cerebral ischemia induced a significant increase in TBA reactive substances (TBARS) level (p<0.001), in comparison with sham-operated animal. Pretreatment with TQ and NSO were resulted a significant decrease in MDA level as compared with ischemic group (66.9+/-1.5 vs. 297+/-2.5 nmol/g tissue for TQ, 10 mg/kg; p<0.001 and 153.5+/-1.3 nmol/g tissue for NSO, 0.384 mg/kg; p<0.001). Using a reversed-phase HPLC system, the amount of TQ in NSO was also quantified and was 0.58% w/w. These results suggest that TQ and NSO may have protective effects on lipid peroxidation process during IRI in rat hippocampus. 相似文献
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The influence of safranal, a constituent of Crocus sativus L. stigmas, on methyl methanesulfonate (MMS)-induced DNA damage was examined using alkaline single-cell gel electrophoresis (SCGE), or comet, assay in multiple organs of mice (liver, lung, kidney, and spleen). NMRI mice were divided into five groups, each of which contained five mice. The animals in different groups were received the following chemicals: physiological saline (10 mL/kg, ip), safranal (363.75 mg/kg, ip), MMS (120 mg/kg, ip), safranal (72.75 mg/kg, ip) 45 min prior to MMS administration, and safranal (363.75 mg/kg, ip) 45 min prior to MMS administration. Mice were sacrificed about 3 h after the administration of direct mutagen MMS, safranal, or saline, and the alkaline comet assay was used to evaluate the influence of safranal on DNA damage in different mouse organs. Increase in DNA migration was varied between 9.08 times (for spleen) and 22.12 times (for liver) in nuclei of different organs of MMS-treated mice, as compared with those of saline-treated animals (p < 0.001). In control groups, no significant difference was found in the DNA migration between safranal- and saline-pretreated mice. The MMS-induced DNA migration in safranal-pretreated mice (363.75 mg/kg) was reduced between 4.54-fold (kidney) and 7.31-fold (liver) as compared with those of MMS-treated animals alone (p < 0.001). This suppression of DNA damage by safranal was found to be depended on the dose, and pretreatment with safranal (72.75 mg/kg) only reduced DNA damage by 25.29%, 21.58%, 31.32%, and 25.88% in liver, lung, kidney, and spleen, respectively (p < 0.001 as compared with saline-treated group). The results of the present study showed that safranal clearly repressed the genotoxic potency of MMS, as measured by the comet assay, in different mouse organs, but the mechanism of this protection needs to be more investigated using different in vitro system assays and different experimental designs. 相似文献