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121.
122.
Coelhan M Bromig KH Glas K Roberts AL 《Journal of agricultural and food chemistry》2006,54(16):5731-5735
A method was developed for the determination of the biocide ortho-phenylphenol (biphenyl-2-ol; OPP) in beer, using deuterated OPP as an internal standard. A new liquid-liquid extraction procedure, employing acetonitrile, diethyl ether, and n-pentane, afforded rapid phase separation. The evaporated extract was derivatized with pentafluorobenzyl bromide in a water-acetonitrile mixture that was buffered with potassium carbonate, followed by extraction of the derivative into cyclohexane and analysis by gas chromatography-mass spectrometry in electron ionization mode. The method enables the detection of OPP in 50 mL of beer at concentrations as low as 0.1 microg/L and provides a linear range of quantification of 0.5-40 microg/L. Samples from 61 beers canned over the past 12 years and sold in 27 countries were analyzed for OPP. In 40 of them, the target compound was present at concentrations of 1.2-40 microg/L. Our investigations indicate that the ends of the cans, which contain sealing material presumably treated with OPP, are responsible for this contamination. 相似文献
123.
Matrix metalloproteinases (MMPs) have been implicated in the pathogenesis of several central nervous system (CNS) diseases. In this study, we investigated the presence of Listeria monocytogenes antigens and detected the expression of MMP-9 and MMP-7 in the brains of 22 sheep with clinical signs and histopathological findings characteristic of listerial meningoencephalitis. Archived sections from the brainstem, cerebrum, and cerebellum were stained for immunohistochemistry. L. monocytogenes antigens were located mainly in the cytoplasm of neutrophils and some macrophages and/or extracellularly within microabscesses of the brainstem. MMP-9 was mainly immunolocalised in the endothelial cells, microglial cells, and neurons especially in inflammatory areas. MMP-7 immunoreactivity was detected in perivascular cuffs, microglial cells, and only a few neurons. Overall, immunohistochemistry in formalin-fixed, paraffin-embedded tissues is a useful tool for the diagnosis of encephalitic listeriosis caused by L. monocytogenes, and MMP-9 and MMP-7 may contribute to the pathogenesis of listerial meningoencephalitis. 相似文献
124.
Mehmet Burak Taşkın Özge Şahin Havva Taskin Orhan Atakol Ali Inal 《Journal of plant nutrition》2018,41(9):1148-1154
Phosphorus (P) is one of the least available mineral nutrients to the plants in calcareous and alkaline soils. In this study, we investigated the synthesis, characterization and use of synthetic nano-hydroxyapatite (NHA), P uptake by plants as well as its residual effects. Soluble P source (H3PO4) was also included as treatment for comparison. NHA prepared by wet chemical techniques, characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and elemental dispersive X-ray (EDX) analysis. NHA and H3PO4 were applied at a rate of 200 mg kg?1 to find out their effects on phosphorus nutrition and growth of lettuce on the low and high calcareous soil. In addition to this, residual effects of NHA and H3PO4 were also determined for lettuce plants grown after first lettuce plants in the both soil. Dry weights of the first and second lettuce plants grown in low and high calcareous soil were significantly increased by applied phosphorus regardless of the source. NHA seems to be more effective than that of ordinary phosphorus source (H3PO4-P) on growth and P concentration of the lettuce plants. The promising results of this study needs to be supported with long term field studies regarding the uptake, translocation and interactions of nano-P with the other elements. 相似文献
125.
126.
Mehmet Tekin Duygu Sari Mursel Catal Cengiz Ikten Petr Smykal R. Varma Penmetsa Eric J. Von Wettberg Cengiz Toker 《Genetic Resources and Crop Evolution》2018,65(1):67-77
Wild Cicer species are considered as useful genetic resources for resistance to biotic and abiotic stresses due to limited resistance in cultivated chickpeas. As a wild perennial species in the genus Cicer L., Cicer isauricum P.H. Davis is an endemic species to Turkey and endangered status according to the International Union for Conservation of Nature criteria. Here we report on its eco-geographic distribution and environmental stresses that affect the species, and advocate for its in situ and ex situ conservation. A new population of the species was discovered in Geyikbay?r?, Güllük Mountains in Antalya, Turkey. Cicer isauricum not only suffers from significant biotic stresses such as ascochyta blight [Ascochyta rabiei (Pass.) Labr.], pod borer (Helicoverpa armigera Hübner) and broomrape (Orobanche sp.), but is also subjected to drought and heat stress in its habitat. Infection with ascochyta blight in natural habitats was diagnosed by molecular techniques, and pod borer and broomrape were observed only phenotypically. PCR amplification of the internal transcribed spacer region of genomic DNA from cultured fungal isolates, yielded sequences with 100% nucleotide identity with the corresponding sequence in GeneBank for Didymella rabiei Kovachevski (anamorph: A. rabiei). The pathogen may have co-evolved with C. isauricum in the newly discovered site. Because C. isauricum is exposed to drought and accompanying heat stress in its natural habitat, it appears able to tolerate heat stress up to 45 °C during podding stage and terminal drought in late summer from its woody, deep rooting. C. isauricum bears multiple flowers per axil, a potentially useful trait in cultivated chickpea. In conclusion, C. isauricum is a potential genetic source for resistance to biotic and abiotic stresses, in need of greater protection due to its endangered status. 相似文献
127.
Todd Z DeSantis Keith Keller Ulas Karaoz Alexander V Alekseyenko Navjeet NS Singh Eoin L Brodie Zhiheng Pei Gary L Andersen Niels Larsen 《BMC ecology》2011,11(1):11
Background
Terabyte-scale collections of string-encoded data are expected from consortia efforts such as the Human Microbiome Project . Intra- and inter-project data similarity searches are enabled by rapid k-mer matching strategies. Software applications for sequence database partitioning, guide tree estimation, molecular classification and alignment acceleration have benefited from embedded k-mer searches as sub-routines. However, a rapid, general-purpose, open-source, flexible, stand-alone k-mer tool has not been available. 相似文献128.
129.
Mustafa Cemek Mehmet Emin Büyükokuro?lu Fatih Aymelek 《Pesticide biochemistry and physiology》2010,98(1):9-18
The present study was designed to investigate the effects of vitamin E (vit E), selenium (Se) and vit E + Se against organophosphate (OP) toxicity in tissues’ trace and major element levels and erythrocyte antioxidant enzyme activities of rats. Trace and major element concentrations in the tissues were measured by inductively coupled plasma-optical emission spectroscopy. Erythrocyte antioxidant enzyme activities were studied by using spectrophotometer. Antioxidant enzyme activities such as superoxide dismutase, glutathione peroxidase and catalase increased in the fenthion-treated groups (control) more than that of sham group subjects. Heart and pectoral muscle tissue Se and Zn concentrations in the control group were higher than sham group. However, jejunum, kidney, liver and pancreas Se and Zn concentrations in the control group were found to be lower than those in the sham group. The Mn concentrations in the all of the tissues were lower in the control group when compared with the sham group. Brain, heart, jejunum, kidney and pancreas Fe concentrations and heart, jejunum, liver, pectoral muscle and pancreas Cu concentrations were found to be lower in the control group. The treatment of vit E, Se and vit E + Se were increased bio-element levels in the many tissue. In conclusion, the results of the present study demonstrate that the tissue trace and major element concentrations and enzymatic antioxidant system were significantly affected OP toxicity. Furthermore, we have shown an association between bio-elements and antioxidant enzymes in OP toxicity. In addition, administration of vit E, Se and vit E + Se might regulate some trace and major element levels in the many tissues. 相似文献
130.
A total of 95 samples of Meloidogyne incognita (60), Meloidogyne javanica (28) and Meloidogyne arenaria (7) collected from West Mediterranean region of Turkey were tested for identifying races of the nematodes using the North Carolina Differential Host Test. Races 2 and 6 of M. incognita were identified in 58 and 2 samples, respectively. Race 1 of M. javanica was identified from all 28 samples. Races 2 and 3 of M. arenaria were identified in 5 and 2 samples, respectively. The results also showed that two races of M. incognita and all races of M. javanica did not attack on pepper cv. California Wonder. These findings may contribute to improving resistant varieties and may also provide basis for developing a cropping system to control root-knot nematodes. 相似文献