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51.
52.
Aviram M Volkova N Coleman R Dreher M Reddy MK Ferreira D Rosenblat M 《Journal of agricultural and food chemistry》2008,56(3):1148-1157
We have analyzed in vivo and in vitro the antiatherogenic properties and mechanisms of action of all pomegranate fruit parts: peels (POMxl, POMxp), arils (POMa), seeds (POMo), and flowers (POMf), in comparison to whole fruit juice (PJ). Atherosclerotic E 0 mice consumed POM extracts [200 microg of gallic acid equivalents (GAE)/mouse/day] for 3 months. Blood samples, peritoneal macrophages (MPM), and aortas were then collected. All POM extracts possess antioxidative properties in vitro. After consumption of PJ, POMxl, POMxp, POMa, or POMf by E (0) mice, the atherosclerotic lesion area was significantly decreased by 44, 38, 39, 6, or 70%, respectively, as compared to placebo-treated group, while POMo had no effect. POMf consumption reduced serum lipids, and glucose levels by 18-25%. PJ, POMxl, POMxp, POMf, or POMa consumption resulted in a significant decrement, by 53, 42, 35, 27, or 13%, respectively, in MPM total peroxides content, and increased cellular paraoxonase 2 (PON2) activity, as compared to placebo-treated mice. The uptake rates of oxidized-LDL by E (0)-MPM were significantly reduced by approximately 15% after consumption of PJ, POMxl, or POMxp. Similar results were obtained on using J774A.1 macrophage cell line. Finally, pomegranate phenolics (punicalagin, punicalin, gallic acid, and ellagic acid), as well as pomegranate unique complexed sugars, could mimic the antiatherogenic effects of pomegranate extracts. We conclude that attenuation of atherosclerosis development by some of the POM extracts and, in particular, POMf, could be related to the combined beneficial effects on serum lipids levels and on macrophage atherogenic properties. 相似文献
53.
Virolainen NE Pikkemaat MG Elferink JW Karp MT 《Journal of agricultural and food chemistry》2008,56(23):11065-11070
Tetracycline (TC) specific luminescent bacterial biosensors were used in a rapid TC residue assay sensitized to meet the EU maximum residue limit (MRL) for TC residues in poultry muscle tissue (100 microg kg(-1)) by membrane-permeabilizing and chelating agents polymyxin B and EDTA. Sensitivities of 5 ng g(-1) for doxycycline, 7.5 ng g(-1) for chlortetracycline, and 25 ng g(-1) for tetracycline and oxytetracycline were reached. Except for doxycycline, the MRLs of these tetracyclines include their 4-epimer metabolites. In the biosensor assay, all four 4-epimers showed induction capacity and antimicrobial activity, and antimicrobial activity was also observed in the inhibition assay, although with lower efficiency than that of the corresponding parent compound in both assays. The biosensor assay is an inexpensive and rapid high-throughput screening method for the detection of 4-epimer TC residues along with their parent compounds. 相似文献
54.
Bernd Zeller Juxiu Liu Nina Buchmann Andreas Richter 《Soil biology & biochemistry》2008,40(5):1155-1166
Tree girdling is a common practice in forestry whenever trees are to be killed without felling. The effect of tree girdling on soil nitrogen (N) mineralisation was estimated in both an old and a young spruce forest. The dynamics of mineral N (NO3−–N and NH4+–N) and soil microbial biomass carbon (MBC) and N (MBN) were determined for different seasons. The in situ net N mineralisation was measured by incubating soil samples in stainless steel cylinders and the gross N mineralisation rates were measured by 15N pool dilution method. Mineral N concentrations increased significantly in the girdled plots in both old and young spruce forests and showed variations between soil horizons and between sampling times. Tree girdling significantly increased net N mineralisation in both spruce forests. Annual net N mineralisation was 64 and 39 kg N ha−1 in O horizon of the girdled plots in old and young forest plots, respectively, compared to 25 and 21 kg N ha−1 in the control plots. Annual N mineralisation in A horizon was similar between girdled and control plots (31 kg N ha−1) in the old forest whereas in the young forest A horizon N mineralisation was about 2.5 times higher in the girdled plots. As a result, the annual carbon budget was significantly more positive in the girdled plots than in the control plots in both old and young forests. However, we found significantly higher gross N mineralisation rates in both horizons in the control plots than the girdled plots in the old forest, but no differences between the treatments in the young forest. The MBC and MBN contents only showed significant changes during the first three months of the experiment and were similar later on. They first decreased as girdling removed the root carbohydrate, amino and organic acid exudation from the C sources for microorganisms then increased two months after the treatment root dieback acted as a new source of C. Mineralising microorganisms enhanced the mineral N concentrations in girdled plots as a result of greater activity rather than larger population size. 相似文献
55.
为更加科学地开展小麦理论研究和提高育种成效,对‘鲁麦14’的构思设计与创制思路、突出特点和以‘鲁麦14’为亲本选育出的品种进行了系统分析。从2001年到2018年,中国科学院、中国农科院、中国农业大学和山东、江苏、河北、安徽、河南、山西、陕西、新疆、贵州、天津9省1市的89家科研单位和育种企业,以‘鲁麦14’为亲本直接育成品种39个、间接育成品种92个,这些品种通过9省2市166次审(认)定和36次国家审定。‘鲁麦14’作为新一代骨干亲本,为全国的小麦生产和育种工作做出了突出贡献。 相似文献
56.
Objectives— To investigate the histologic diagnosis and incidence of new mammary tumor growth in the remaining mammary chain tissue after regional mastectomy.
Study Design— Prospective clinical study.
Animals— Female dogs (n=99) that had excision of a single mammary tumor.
Methods— Female dogs that had regional mastectomy to remove a single tumor were followed for ≥1 year postoperatively. Data regarding tumor type, tumor recurrence, and development of metastasis were recorded.
Results— Fifty-seven (58%) dogs developed a new tumor in the ipsilateral mammary chain after the 1st surgery; 77% had repeat surgery. There was no significant correlation between the time to new tumor development and the histologic diagnosis for the 1st and 2nd tumor types. In 31 dogs, the histologic diagnosis for initial and subsequent tumors was identical and there was a significant correlation such that dogs with an initial malignant tumor are likely to develop another malignant tumor ( P =.0089). The histologic classification of the new tumor was likely to be malignant if it was located close to the side where the initial tumor had been removed ( P =.026).
Conclusions— Our results show that 58% of dogs developed a new tumor in the remaining mammary glands of the ipsilateral chain after regional mastectomy for removal of a single tumor.
Clinical Relevance— This should be taken into account when deciding on the surgical management (radical or regional mastectomy) in dogs with single mammary tumors. 相似文献
Study Design— Prospective clinical study.
Animals— Female dogs (n=99) that had excision of a single mammary tumor.
Methods— Female dogs that had regional mastectomy to remove a single tumor were followed for ≥1 year postoperatively. Data regarding tumor type, tumor recurrence, and development of metastasis were recorded.
Results— Fifty-seven (58%) dogs developed a new tumor in the ipsilateral mammary chain after the 1st surgery; 77% had repeat surgery. There was no significant correlation between the time to new tumor development and the histologic diagnosis for the 1st and 2nd tumor types. In 31 dogs, the histologic diagnosis for initial and subsequent tumors was identical and there was a significant correlation such that dogs with an initial malignant tumor are likely to develop another malignant tumor ( P =.0089). The histologic classification of the new tumor was likely to be malignant if it was located close to the side where the initial tumor had been removed ( P =.026).
Conclusions— Our results show that 58% of dogs developed a new tumor in the remaining mammary glands of the ipsilateral chain after regional mastectomy for removal of a single tumor.
Clinical Relevance— This should be taken into account when deciding on the surgical management (radical or regional mastectomy) in dogs with single mammary tumors. 相似文献
57.
58.
Digestibility,growth and pigmentation of astaxanthin,canthaxanthin or lutein diets in Lake Kurumoi rainbowfish,Melanotaenia parva (Allen) cultured species 下载免费PDF全文
Nina Meilisza Dedi Jusadi Muhammad Zairin Jr. I Made Artika Nur Bambang Priyo Utomo Tutik Kadarini Muhammad Agus Suprayudi 《Aquaculture Research》2017,48(11):5517-5525
New cultured ornamental fish namely Lake Kurumoi rainbowfish Melanotaenia parva (Allen) run into reduced of colour performances when reared in the aquaria, consequently, fish feed must be added with carotenoids as a pigment source. The aim of this study was to evaluate the digestibility, growth and pigmentation of astaxanthin, canthaxanthin and lutein in diet. Apparent digestibility coefficients (ADC) of dry matter, lipid, protein, carotenoids, growth and pigmentation were studied in twenty fish after 14 and 56 days of observation. The single‐dose supplementation of 100 mg/kg of astaxanthin, canthaxanthin, or lutein diets on fish was fed by apparent satiation. The basal diet without carotenoids was used as control. The result showed that the ADC of carotenoids of test diets was higher compared to control. Fish fed astaxanthin diet had higher survival rate (96.67 ± 2.89%), colour measurements of lightness (57.60 ± 7.46%), a*‐values (4.66 ± 1.20), total carotenoids content in skin (33.75 ± 5.02 mg/kg) and muscle (2.16 ± 0.74 mg/kg). Astaxanthin also increased the growth after 14 days (2.00% ± 0.19%/days) but there was no significantly different at the end of experiment. The yellowish‐orange colour performance was more rapidly achieved by fish fed astaxanthin diet after 28 days experimentation. These values suggested that dietary carotenoids were required and astaxanthin diet was superior to other diets for skin pigmentation of Lake Kurumoi rainbowfish. 相似文献
59.
Joaquín Soler Catherine Boisneau Philippe Jug Nina Richard Yann Guerez Laure Morisseau Karl Matthias Wantzen Rafael Araujo 《水产资源保护:海洋与淡水生态系统》2019,29(10):1758-1770
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60.
Dissolved and colloidal phosphorus fluxes in forest ecosystems—an almost blind spot in ecosystem research 下载免费PDF全文
Roland Bol Dorit Julich Dominik Brödlin Jan Siemens Klaus Kaiser Michaela Anna Dippold Sandra Spielvogel Thomas Zilla Daniela Mewes Friedhelm von Blanckenburg Heike Puhlmann Stefan Holzmann Markus Weiler Wulf Amelung Friederike Lang Yakov Kuzyakov Karl‐Heinz Feger Nina Gottselig Erwin Klumpp Anna Missong Carola Winkelmann David Uhlig Jakob Sohrt Klaus von Wilpert Bei Wu Frank Hagedorn 《植物养料与土壤学杂志》2016,179(4):425-438
Understanding and quantification of phosphorus (P) fluxes are key requirements for predictions of future forest ecosystems changes as well as for transferring lessons learned from natural ecosystems to croplands and plantations. This review summarizes and evaluates the recent knowledge on mechanisms, magnitude, and relevance by which dissolved and colloidal inorganic and organic P forms can be translocated within or exported from forest ecosystems. Attention is paid to hydrological pathways of P losses at the soil profile and landscape scales, and the subsequent influence of P on aquatic ecosystems. New (unpublished) data from the German Priority Program 1685 “Ecosystem Nutrition: Forest Strategies for limited Phosphorus Resources” were added to provide up‐to‐date flux‐based information. Nitrogen (N) additions increase the release of water‐transportable P forms. Most P found in percolates and pore waters belongs to the so‐called dissolved organic P (DOP) fractions, rich in orthophosphate‐monoesters and also containing some orthophosphate‐diesters. Total solution P concentrations range from ca. 1 to 400 µg P L?1, with large variations among forest stands. Recent sophisticated analyses revealed that large portions of the DOP in forest stream water can comprise natural nanoparticles and fine colloids which under extreme conditions may account for 40–100% of the P losses. Their translocation within preferential flow passes may be rapid, mediated by storm events. The potential total P loss through leaching into subsoils and with streams was found to be less than 50 mg P m?2 a?1, suggesting effects on ecosystems at centennial to millennium scale. All current data are based on selected snapshots only. Quantitative measurements of P fluxes in temperate forest systems are nearly absent in the literature, probably due to main research focus on the C and N cycles. Therefore, we lack complete ecosystem‐based assessments of dissolved and colloidal P fluxes within and from temperate forest systems. 相似文献