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251.
Lipoprotein-associated paf (LA-paf) was found in washed human platelets and monocyte/macrophage-like U937 cells 总被引:2,自引:0,他引:2
Ruth Korth Klaus Zimmermann Werner Oskar Richter 《Chemistry and physics of lipids》1994,70(2):109-119
Beyond cholesterol, inflammatory ether phospholipids such as platelet-activating factor (paf) may play a role in atherogenesis. (1) We detected a paf-like compound (‘LA-paf’) associated with human serum lipoproteins, mainly in LDL but not with the lipoprotein-poor fraction. (2) LA-paf was also found in washed human platelets, from where it was partially released during platelet aggregation in response to paf (50 nM) or thrombin (1 U). In addition, resident monocyte/macrophage-like U937 cells carried huge amounts of LA-paf (41 ng per 107 cells) and metabolized added [3H]paf to a labelled compound co-eluting with the retention time of LA-paf in standard HPLC. (3) Functionally, LA-paf had a comparable potency to synthetic paf, because LA-paf aggregated washed aspirin-treated platelets in a concentration-dependent manner. The specific paf receptor antagonist WEB2086 inhibited the platelet aggregation induced by three distinct LA-paf preparations as compared with synthetic paf with similar inhibitory concentrations (IC50: 35.6 ± 12.8, 24.0 ± 4.0, 38.0 ± 15.8 nM for LA-paf, and 43.6 ± 6.5 nM for synthetic paf), indicating that LA-paf interacted with paf receptors. (4) However, LA-paf had a distinct retention time using high-pressure liquid chromatography (HPLC) as compared with synthetic paf. LA-paf eluted at 9–15 min and synthetic paf at 21–24 min. In addition, total and non-specific [3H]paf binding to intact washed human platelets was affected differently by the two unlabelled agonists: while LA-paf increased total and non-specific (but not specific) binding in a significant manner (P < 0.002 and P < 0.007) as LDL did (P < 0.006 and P < 0.03), synthetic paf decreased total binding (P < 0.03). Similarly, low-density lipoproteins (LDL) increased significantly the total [3H]paf binding. In contrast, paf did not affect specific [125I]LDL binding to human fibroblasts. Our results show the presence of LA-paf in lipoproteins, 相似文献
252.
Restriction fragment length polymorphisms at the phytohemagglutinin (PHA) locus were determined among 21 genotypes ofPhaseolus vulgaris, P. coccineus, P. acutifolius, P. lunatus, and threeVigna species, using five restriction enzymes and one double digestion, in order to provide molecular evidence for their genetic relatedness. The dissimilarity between genotypes was estimated from binary RFLP data. The dissimilarity was high among species (from 0.75 to 0.95), and of variable extent among genotypes of the same species (0.33–0.89). InP. vulgaris, two different DNA hybridization patterns were found, giving further evidence for two major gene pools in that species. The restriction patterns ofP. vulgaris var.aborigineus, the putative ancestral form ofP. vulgaris, exhibit clear homology toP. vulgaris genotypes. An undefined landrace from Taiwan could be identified as aP. vulgaris genotype. RFLP-based trees for the phytohemagglutinin genes of the species studied were computed with several distance matrix and parsimony methods. 相似文献
253.
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255.
Solar Cells: Large Efficiency Improvement in Cu2ZnSnSe4 Solar Cells by Introducing a Superficial Ge Nanolayer (Adv. Energy Mater. 21/2015) 下载免费PDF全文
256.
Klaus Honomichl 《Zoomorphology》1982,101(3):177-186
Summary Only one non-ciliary proprioceptor is developed on the mandible of Thrips. It consists of two bipolar, multiterminal sense cells, the dendrites of which form a strand extended between the tentorium and the back mandibular margin. The dendritic terminals are embedded in an electron-dense, homogeneous matrix, which obviously represents the stimulus transmitting structure. The strand is stretched, if the mandible is moved forwards and upwards. In Thrips, the system of proprioceptors monitoring the mandibular movement is reduced extensively compared with other pterygote insects. This is linked up with the far-reaching reduction of the mobility of the mandible itself.This study is dedicated to Mrs. Signe Ulmer, in memory of her winning nature, her invaluable assistance, and her disciplineSupported by a grant from the Deutsche Forschungsgemeinschaft (Ho 826/2-2) 相似文献
257.
Connexin43 interacts with NOV: a possible mechanism for negative regulation of cell growth in choriocarcinoma cells 总被引:13,自引:0,他引:13
Gellhaus A Dong X Propson S Maass K Klein-Hitpass L Kibschull M Traub O Willecke K Perbal B Lye SJ Winterhager E 《The Journal of biological chemistry》2004,279(35):36931-36942
258.
Kyttaris VC Juang YT Tenbrock K Weinstein A Tsokos GC 《Journal of immunology (Baltimore, Md. : 1950)》2004,173(5):3557-3563
259.
Henryk Flachowsky Iris Szankowski Thilo C. Fischer Klaus Richter Andreas Peil Monika Höfer Claudia Dörschel Sylvia Schmoock Achim E. Gau Heidrun Halbwirth Magda-Viola Hanke 《Planta》2010,231(3):623-635
Transgenic apple plants (Malus × domestica cv. ‘Holsteiner Cox’) overexpressing the Leaf Colour (Lc) gene from maize (Zea mays) exhibit strongly increased production of anthocyanins and flavan-3-ols (catechins, proanthocyanidins). Greenhouse plants investigated in this study exhibit altered phenotypes with regard to growth habit and resistance traits. Lc-transgenic plants show reduced size, transversal gravitropism of lateral shoots, reduced trichome development, and frequently reduced shoot diameter and abnormal leaf development with fused leaves. Such phenotypes seem to be in accordance with a direct or an indirect effect on polar-auxin-transport in the transgenic plants. Furthermore, leaves often develop necrotic lesions resembling hypersensitive response lesions. In tests, higher resistance against fire blight (caused by the bacterium Erwinia amylovora) and against scab (caused by the fungus Venturia inaequalis) is observed. These phenotypes are discussed with respect to the underlying altered physiology of the Lc-transgenic plants. The results are expected to be considered in apple breeding strategies. 相似文献
260.
Minghua Zhou Bo Zhu Nicolas Brüggemann Jessica Bergmann Yanqiang Wang Klaus Butterbach-Bahl 《Ecosystems》2014,17(2):286-301
Guaranteeing high crop yields while reducing environmental impacts of nitrogen fertilizer use due to associated losses of N2O emissions and nitrate (NO3 ?) leaching is a key challenge in the context of sustainable intensification of crop production. However, few field data sets are available that explore the effect of different forms of N management on yields as well as on N losses in the form of N2O or NO3 ?. Here we report on a large-scale field lysimeter (8 × 4 m2) experiment, which was designed to determine soil CH4 and N2O emissions, NO3 ? leaching losses and crop yields from a subtropical rain-fed wheat–maize rotation in the Sichuan Basin, one of the most intensively used agricultural regions in China. One control and three different fertilizer treatments with the same total rate of N application (280 kg N ha?1 y?1) were included: NF: control (no fertilizer); NPK: synthetic N fertilizer; OMNPK: synthetic N fertilizer plus pig manure; RSDNPK: synthetic N fertilizer plus crop residues. As compared to the standard NPK treatment, annual NO3 ? leaching losses for OMNPK and RSDNPK treatments were decreased by 36 and 22%, respectively (P < 0.05). Similarly, crop yield-scaled NO3 ? leaching for NPK treatment was higher than those for either OMNPK or RSDNPK treatments (P < 0.05). Direct N2O emissions for RSDNPK treatment were decreased as compared with NPK and OMNPK treatments (P < 0.05). Furthermore, the yield-scaled GWP (global warming potential) was lower for the treatments where either pig manure or crop residues were incorporated as compared to the standard NPK treatment (P < 0.05). Our study indicates that it is possible to reduce the negative environmental impact of NO3 ? leaching and N2O emissions without compromising crop productivity. Yield-scaled NO3 ? leaching, similar to the yield-scaled GWP, represents another valuable-integrated metric to address the dual goals of reducing nitrogen pollution and maintaining crop grain yield for a given agricultural system. 相似文献