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排序方式: 共有165条查询结果,搜索用时 234 毫秒
41.
Dannenberger D Lorenz S Nuernberg G Scollan N Ender K Nuernberg K 《Journal of agricultural and food chemistry》2006,54(1):182-188
In a large study, 64 German Holstein and German Simmental bulls were randomly allocated to either an indoor concentrate system or periods of pasture feeding followed by a finishing period on a concentrate containing linseed to enhance the contents of beneficial fatty acids in beef. This paper reports the diet effects on the concentration of 12-methyltridecanal (12-MT) and further fatty aldehydes released from plasmalogens in the phospholipids of longissimus muscle of the bulls. Because of the trace level of the important odorant 12-MT in beef, the determination of fatty aldehydes in phospholipids was done by acidic hydrolysis and the reaction of the aldehydes with 2,4-DNPH followed by high-pressure liquid chromatography (HPLC) analysis. The diet affected the 12-MT concentrations in the muscle phospholipids of both breeds. Pasture feeding significantly increased the 12-MT concentrations up to 350 microg/100 g fresh muscle in the muscle phospholipids of German Holstein and German Simmental bulls as compared with the concentrate-fed bulls. Furthermore, pasture feeding resulted in a significant increase of n-octadecanal in the muscle phospholipids of both breeds up to 39.5 mg/100 g fresh muscle. The concentration of n-hexadecanal was not affected by the diet. Pasture feeding as compared to concentrate feeding significantly decreased the concentration of n-octadec-9-enal in the muscle phospholipids. Summarizing, pasture feeding increased the 12-MT concentration, which can be associated with meat of more intensive aroma and better taste. 相似文献
42.
Lutze G Lutze G Kutschmann K Schröpel M 《Berliner und Münchener tier?rztliche Wochenschrift》2002,115(7-8):297-302
Two different laboratory assays exist for the determination of clotting factor VIII activities in human plasma. One method is based on the one-stage clotting principle, the other one on the chromogenic principle. To evaluate the suitability for veterinary medicine human plasma and plasma of ten mammalian species (pig, cattle, dog, cat, zebra, llama, snow leopard, greater kudu, horse-like antelope, mink) were examined with each method. Factor VIII activities in human plasma determined using both assays were in a good agreement. Results of factor VIII activities in plasma of mammals obtained with both methods were similar, if a species-specific reference plasma was used. The practicability of the chromogenic method was reduced. However, the factor VIII activities differed nonsystematically up to 500% between both methods, if a human plasma was used as a reference plasma. Determination of factor VIII activities in plasma of mammals using the chromogenic assay cannot be recommended. 相似文献
43.
Gerd Weidemann 《植物养料与土壤学杂志》1999,162(4):359-361
Dead organic matter and soil biota — qualities, correlations and interrelationships At the biannual meeting of the German Soil Science Society at Konstanz, September 7 to 12, 1997, a symposium was held to summarize actual research on the quality of soil dead organic matter and its interrelations with the soil biota. This introduction outlines the frame and reports on lectures by O. Dilly and J. C. Munch, L. Beyer and U. Irmler, by W. Foissner and also by U. Graefe not included in the following papers. 相似文献
44.
Tobias Belschner Johanna Ferretti Harry v. Strehlow Sarah B. M. Kraak Ralf Dring Gerd Kraus Alexander Kempf Christopher Zimmermann 《Fish and Fisheries》2019,20(1):97-109
Despite regular reforms, problems under the EU's Common Fisheries Policy (CFP) persist. In order to identify priorities for future reforms of the policy, we developed an analytical framework consisting of 17 criteria and specifying indicators, derived from scientific, wider fisheries, and common resources literature. We applied the framework to the CFP governance system, its regulations, institutions, and processes at EU as well as member state level. The results show that the CFP does not fully meet any of the 17 criteria for an effective resource policy. Its performance was assessed as “neutral” regarding 10 criteria and “negative” regarding seven criteria. Trend analysis shows that there is a slightly positive trend regarding the CFP's performance, with five criteria trending positively, 11 showing a neutral trend and only one criterion trending negatively (simplicity of rules). The analysis identified five criteria which are performing badly and have not improved over time: simplicity of rules, user‐pays principle, resource efficiency, accountability, and compliance mechanisms. Future reforms of the CFP should first and foremost address these criteria while continuing efforts to improve the CFP's performance regarding other criteria. The evaluation of the CFP demonstrates the applicability of the analytical framework which can also be applied to other multilevel fisheries governance systems. Moreover, the results can inform reforms of Regional Fisheries Management Organisations. Like the CFP, these institutions manage transboundary fisheries and have not effectively addressed the issues of resource rent capture and resource efficiency. 相似文献
45.
【目的】 将作物时空分布数据应用于核事故农业风险决策支持系统,体现遥感作物制图在核事故农业风险决策中的重要性。【方法】 文章以大亚湾核电基地为研究案例,对其周边地区的作物轮作系统进行遥感制图;作物时空分布数据经后处理,上传至核事故农业风险决策支持系统,实现作物样本任务的自动生成,以及放射性核素浓度的时空分布模拟。【结果】 提出的遥感制图方法可以在耕地破碎、云雨繁密区识别作物轮作系统,快速、准确地提供大范围作物时空分布数据。经过处理的作物时空分布数据,能够方便地应用于决策支持系统,辅助完成特定或优先区作物样本任务点的自动生成,以及放射性核素浓度时空分布的模拟。【结论】 遥感作物制图与核事故农业风险决策支持系统相结合,可进一步提高采样的有效性,提升放射性核素空间和时间分布模拟与预测的准确性。从而帮助决策者制定核污染监测和评估策略、修复计划,科学指导农业生产的恢复。未来,有必要深入研究遥感作物制图在核事故农业风险决策中的应用,充分发挥遥感技术与数据的优势,规避核事故对农业生产带来的风险。 相似文献
46.
The acidification of the soil and percolation water at soildepths from 150 to 500 cm was studied at the Solling spruce sitefrom 1991 to 1996. NH4Cl exchangeable cations of the fineearth and bedrock fractions were obtained from different depthsand the soil solution composition was monitored at 150, 200,300, 400 and 500 cm depths using seven suction lysimeters at each depth.In the seepage water collected from 150 and 200 cm depth, pHvalues decreased in the period 1991 to 1996, but no significantchanges were observed in solutions collected below 200 cm depth.Element budgets of Al and Mb (Na, K, Mg, Ca) cationsindicated that buffering by exchange of Al with Mb cationsoccurred mainly in surface 200 cm soil depth. High variabilities in concentrations of SO4 (at 150 cm) andMa (Al, Mn, H, Fe) cations (at 300 and 500 cm) wereobserved. High variabilities in Ma cations could beassigned to one of the lysimeters at each depththat extracted low pH solutions. The amount of exchangeablecations in the fine earth and the bedrock fractions indicatedthat the acidification front (exchangeable Mb cations < 80equivalent percent) had occurred to soil depth of more than 360cm, but the extent of acidification that might have occurred inthe preindustrial period is not known. In both fine earth andbedrock fractions, depthwise changes of exchangeable Ma andMb cations were quite similar, suggesting that rockfractions have contributed to proton buffering not only bysilicate weathering but also by cation exchange. 相似文献
47.
George A. Ballard Jennifer J. Warnock Gerd Bobe Katja F. Duesterdieck-Zellmer Lindsay Baker Wendy I. Baltzer Jesse Ott 《Research in veterinary science》2014
Tissue engineering is a promising field of study toward curing the meniscal deficient stifle; however the ideal cell type for this task is not known. We describe here the extraction of synoviocytes and meniscal fibrochondrocytes from arthroscopic debris from six dogs, which were cultured as tensioned bioscaffolds to synthesize meniscal-like fibrocartilage sheets. Despite the diseased status of the original tissues, synoviocytes and meniscal fibrochondrocytes had high viability at the time of removal from the joint. Glycosaminoglycan and collagen content of bioscaffolds did not differ. Meniscal fibrochondrocyte bioscaffolds contained more type II collagen, but collagen deposition was disorganized, with only 30–40% of cells viable. The collagen of synoviocyte bioscaffolds was organized into sheets and bands and 80–90% of cells were viable. Autologous, diseased meniscal fibrochondrocytes and synoviocytes are plausible cell sources for future meniscal tissue engineering research, however cell viability of meniscal fibrochondrocytes in the tensioned bioscaffolds was low. 相似文献
48.
Jennifer J. Warnock Jason Spina Gerd Bobe Katja F. Duesterdieck-Zellmer Jesse Ott Wendy I. Baltzer Brian K. Bay 《Veterinary journal (London, England : 1997)》2014,199(1):49-56
Meniscal injury is a common cause of canine lameness. Tissue engineered bioscaffolds may be a treatment option for dogs suffering from meniscal damage. The aim of this study was to compare in vitro meniscal-like matrix formation and biomechanical properties of porcine intestinal submucosa sheets (SIS), used in canine meniscal regenerative medicine, to synoviocyte-seeded SIS bioscaffold (SSB), cultured with fetal bovine serum (SSBfbs) or chondrogenic growth factors (SSBgf). Synoviocytes from nine dogs were seeded on SIS and cultured for 30 days with 17.7% fetal bovine serum or recombinant chondrogenic growth factors (IGF-1, TGFβ1 and bFGF). The effect on fibrochondrogenesis was determined by comparing mRNA expression of collagen types Iα and IIα, aggrecan, and Sry-type homeobox protein-9 (SOX9) as well as protein expression of collagens I and II, glycosaminoglycan (GAG), and hydroxyproline.The effect of synoviocyte seeding and culture conditions on biochemical properties was determined by measuring peak load, tensile stiffness, resilience, and toughness of bioscaffolds. Pre-culture SIS contained 13.6% collagen and 2.9% double-stranded DNA. Chondrogenic growth factor treatment significantly increased SOX9, collagens I and IIα, aggrecan gene expression (P < 0.05), and histological deposition of fibrocartilage extracellular matrix (GAG and collagen II). Culture with synoviocytes increased SIS tensile peak load at failure, resilience, and toughness of bioscaffolds (P < 0.05). In conclusion, culturing SIS with synoviocytes prior to implantation might provide biomechanical benefits, and chondrogenic growth factor treatment of cultured synoviocytes improves in vitro axial meniscal matrix formation. 相似文献
49.
In a laboratory study, a heavy metal contaminated topsoil from a former sewage farm in Berlin was amended with different additives: lime, ash/gypsum, bark mulch, brown coal and combinations of these treatments. After 8 weeks of incubation, pH of the lime and ash/gypsum treatments increased to 6.2–6.3 compared to 5.2–5.3 in the control and the other treatments. Organic-C content rose from 42 g/kg in the control to 46–53 g/kg in the organic amendments. In reaction to the pH-increase the water soluble fraction of Cd, Cu and Zn was reduced by roughly 60%, 30% and 80% respectively. Cd- and Zn-binding forms as determined with NH4-acetate- and EDTA-extracts were not affected by the treatments, while the ash/gypsum-treatment increased EDTA-extractable Pb by 17%. The exchangeable Cu-Fraction (NH4-acetate extract) was reduced in all treatments to 82–93% of the control values, with the greatest effects in the tree bark amendment. The FREUNDLICH adsorption isotherms also show an increased sorption of heavy metals in the lime and ash/gypsum treatments. Organic amendments alone or in combination with lime had little effect on heavy metal adsorption. 相似文献
50.