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H Liebermann H Bergmann E Lange H Schirrmeier P Solisch 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1992,39(5):317-326
Purified and concentrated preparations of virus from liver extracts of infected rabbits contain virus specific components with sedimentation coefficients of about 175, 110 and sometimes 133S and more slow units. Full and empty virus particles with a diameter of about 34 nm were shown electron microscopically in the corresponding 175 and 110S fractions of the sucrose density gradient. The average of buoyant density of the 175, 133, 110S and more slow units are 1.36, 1.32 and 1.31 g/ml respectively. The extinction coefficient E260 nm is 4.3 +/- 0.7 cm2/mg. The RNA content is 17 +/- 4%. SDS-PAGE shows a "65" kD protein as a single or major component. Beside smaller polypeptides with lower intensities, the 67 kD polypeptide reacts positively in the Western blot with polyclonal antibodies of rabbits. The molecular weight of the virus is 15 +/- 4 x 10(6)D. The pH stability of the 175S unit was also tested. 相似文献
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Sensitivity of seven PCRs for early detection of koi herpesvirus in experimentally infected carp,Cyprinus carpio L., by lethal and non-lethal sampling methods 下载免费PDF全文
Koi herpesvirus (KHV) causes an economically important, highly infectious disease in common carp and koi, Cyprinus carpio L. Since the occurrence of mass mortalities worldwide, highly specific and sensitive molecular diagnostic methods have been developed for KHV detection. The sensitivity and reliability of these assays have essentially focused at the detection of low viral DNA copy numbers during latent or persistent infections. However, the efficacy of these assays has not been investigated with regard to low-level viraemia during acute infection stages. This study was conducted to compare the sensitivity of seven different polymerase chain reaction (PCR) assays to detect KHV during the first hours and days post-infection (hpi; dpi), using lethal and non-lethal sampling methods. The results highlight the limitations of the assays for detecting virus during the first 4 dpi despite rapid mortality in experimentally infected carp. False-negative results were associated with time post-infection and the tissue sampled. Non-lethal sampling appears effective for KHV screening, with efficient detection in mucus samples obtained from external swabs during this early infection period (<5 dpi), while biopsies from gills and kidney were negative using the same PCR assays. Non-lethal sampling may improve the reliability of KHV detection in subclinical, acutely infected carp. 相似文献
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Remediation of an uranium‐mine soil from Settendorf (East Germany) includes phytoextraction under conditions which make its heavy metals more plant‐available but less leachable. A second way is active inhibition of heavy metal uptake by the plant. In a pot trial with Chinese cabbage (Brassica chinensis L.), planted and unplanted soil samples were daily irrigated with deionized water or aqueous solutions with a total of (g (kg soil)–1) CaCl2 (0.26 Ca), NH4Cl (1.39), casein, sucrose, citric acid (13), and an extract of rape (B. napus L.) shoots (13 DW) in a phytotron for 26 d. Water‐irrigated plants were also treated with a 50 mM citric acid solution (10.5 g (kg soil)–1) 6 and 7 d prior to harvesting. Total elements in plant tissue and soluble elements in aqueous extracts from control and postharvest soils were determined by ICP‐AES. Supplements of NH , and the NH ‐generating casein and rape extract reduced soil pH during nitrification, and increased plant uptake of Cd, Cu, Ni, and Zn. Citric acid at 50 mM adjusted soil to pH 4.5–6.0 and enhanced uptake of all elements. Long‐term application of sucrose and citric acid increased pH and inhibited uptake of Cd, Cr, Cu, Ni, and Zn. Contemporarily, leaching of heavy metals and humic substances was lowest with Ca and NH and highest with sucrose and citric acid amendments. It is concluded that Chinese cabbage grown for chelate‐assisted phytoextraction should be supplied with Ca and NH to obtain a high plant biomass on soil with a low hazard of leaching. Metal uptake should be stimulated by application of chelator 7 d prior to harvesting. Undesired uptake of heavy metals by Chinese cabbage determined as food should be inhibited with carbohydrate amendments. Long‐term application of NH or chelator, which reduces the solubility of certain elements but increases their uptake moderately, is recommended as a tool for continuous phytoextraction technologies. 相似文献
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Tryptophan-N-glucoside in fruits and fruit juices 总被引:1,自引:0,他引:1
In extracts prepared from various fruits as well as in fruit juices a single tryptophan glycoconjugate was detected by HPLC-MS analysis. Product ion spectra demonstrated the N-glycosidic linkage of a hexose moiety to the indole nitrogen. For structure elucidation, the novel tryptophan glycoside was isolated from pear juice and identified as N(1)-(beta-D-glucopyranosyl-(4)C(1))-L-tryptophan by (1)H, HH-COSY and (13)C NMR spectroscopy. Finally, we disclosed the biosynthetic origin of the novel tryptophan metabolite by demonstrating the enzymatic glycosylation of deuterium-labeled tryptophan, which was applied to pear fruit. 相似文献
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Zusammenfassung Durch Anwendung des TTC-Schnelltestes wurde versucht, ein praktisch brauchbares Keimprüfungsverfahren für Kaffeesamen zu entwickeln. Es wird eine Routinemethode zur Keimprüfung mit TTC vorgeschlagen, die mit isolierten Embryonen von Kaffee arbeitet. Dieses Verfahren wurde an 4 verschiedenen Samenproben von Kaffee überprüft. Die Übereinstimmung der Ergebnisse aus den Keimprüfungen, die vergleichend unter natürlichen Bedingungen vorgenommen wurden, mit denen des TTC-Testes war gut, so daß eine praktische Anwendung des Verfahrens für den Kaffeeanbau gerechtfertigt erscheint.
Application of triphenyltetrazolium chloride for rapid testing of the viability of seeds fromCoffea arabica L.
Summary Using TTC we tried to develop a useful method for testing the germination capability of coffee seeds. A routine test method for germination using TTC is suggested, which works with isolated embryos of the coffee seeds. This method was tested with 4 different samples of coffee seeds and compared with the germination of coffee seeds at natural conditions. The agreement of the results from both germination tests was very good. Therefore the application of the test with TTC is proposed for the practical coffee farming.
-- Coffea arabica L.
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89.
Jürgen Bender Elke Bergmann Hans-Joachim Weigel 《Water, air, and soil pollution》2006,176(1-4):253-267
A screening study with 25 common European wild plant species were performed over three consecutive growing seasons to investigate the effects of ozone on plant growth, reproductive development, and resource allocation. Species were grown from seedling stage until the flowering stage or seed maturity, respectively, in open-top chambers in different ozone-enriched atmospheres at environmentally-relevant concentrations. Ozone treatments covered a range of concentrations from 20 to 55 ppb ozone (seasonal 8 h daily mean). The experiments revealed significant differences between species with respect to the sensitivity of different end points toward ozone exposure. Ozone caused a significant reduction in leaf biomass of more than 20% in six species, and a significant increase in leaf biomass in three species. The relative ozone sensitivities of the species in terms of leaf biomass were different from those inferred from total shoot biomass or seed production, indicating that ozone alters resource allocation patterns in wild plants but there was considerable variation between species in effects on the allocation to leaves, stems, flowers/fruits and seeds. Germinability of seeds was affected by ozone such that germination rate was up to 30% lower in ozone-treated plants compared to control plants. Based on the genotypes screened and by combining different sensitivity criteria (vegetative growth, reproductive growth, exposure-growth response relationships) Malva sylvestris must be regarded as the most sensitive species in this study. 相似文献
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