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101.
Albrecht Hase 《Journal of pest science》1940,16(12):140-142
Ohne Zusammenfassung
Mit 1 Abbildung 相似文献
102.
S.D. Dumusc E.C. Ontsouka M. Schnyder S. Hartnack C. Albrecht R.M. Bruckmaier I.A. Burgener 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2014,28(6):1684-1691
Background
Cyclooxygenase‐2 (COX‐2) is a key enzyme in the synthesis of pro‐inflammatory prostaglandins and 5‐lipoxygenase (5‐LO) is the major source of leukotrienes. Their role in IBD has been demonstrated in humans and animal models, but not in dogs with chronic enteropathies (CCE).Hypothesis
COX‐2 and 5‐LO are upregulated in dogs with CCE.Animals
Fifteen healthy control dogs (HCD), 10 dogs with inflammatory bowel disease (IBD), and 15 dogs with food‐responsive diarrhea (FRD).Methods
Prospective study. mRNA expression of COX‐2, 5‐LO, IL‐1b, IL‐4, IL‐6, TNF, IL‐10 and TFG‐β was evaluated by quantitative real‐time RT‐PCR in duodenal and colonic biopsies before and after treatment.Results
COX‐2 expression in the colon was significantly higher in IBD and FRD before and after treatment (all P < .01). IL‐1b was higher in FRD in the duodenum after treatment (P = .021). TGF‐β expression was significantly higher in the duodenum of HCD compared to FRD/IBD before treatment (both P < .001) and IBD after treatment (P = .012). There were no significant differences among groups and within groups before and after treatment for IL‐4, IL‐6, TNF, and IL‐10. There was a significant correlation between COX‐2 and IL‐1b in duodenum and colon before treatment in FRD and IBD, whereas 5‐LO correlated better with IL‐6 and TNF. IL‐10 and TGF‐β usually were correlated.Conclusions and Clinical Importance
COX‐2 is upregulated in IBD and FRD, whereas IL‐1b and TGF‐β seem to be important pro‐ and anti‐inflammatory cytokines, respectively. The use of dual COX/5‐LO inhibitors could be an interesting alternative in the treatment of CCE. 相似文献103.
104.
Claus A Schreiter P Weber A Graeff S Herrmann W Claupein W Schieber A Carle R 《Journal of agricultural and food chemistry》2006,54(23):8968-8976
Because the impact of agronomical factors on bakery products quality is still an insufficiently studied field, acrylamide contents of breads produced from flours of nine wheat, two rye, and two spelt varieties harvested in 2003 and 2004 were investigated. It could be demonstrated that acrylamide content in bread strongly depends on the cultivar, with extremes differing by a factor of 5.4 due to marked differences in free asparagine and crude protein contents. Nitrogen fertilization also resulted in elevated amino acid and protein contents, thus increasing acrylamide levels from 10.6 to 55.6 mug/kg. Independent of fertilization, harvest year turned out to be another factor influencing acrylamide formation. Breads produced from 2003 flours showed significantly higher acrylamide contents than those of 2004, which was ascribed to favorable light and temperature conditions during the cultivation period, thus enhancing amino acid and protein contents. Sprouting of the grain also resulted in significantly higher acrylamide levels, which was attributed to elevated enzyme activities and the formation of precursors from protein and starch. Furthermore, bakery products made from flours with higher extraction rates were shown to contain higher acrylamide levels resulting from extracted free asparagine and protein from the aleuron layers of the cereal grain. 相似文献
105.
106.
107.
Albrecht Hase 《Journal of pest science》1931,7(12):143-144
Ohne Zusammenfassung 相似文献
108.
Albrecht Hase 《Journal of pest science》1929,5(12):159-160
Ohne Zusammenfassung 相似文献
109.
Ammonium salts used as fertilizers may cause soil acidification by two different processes: nitrification in soil and net release of protons from roots. Their influence on soil pH may vary depending on the distance from root surface. The aim of this study was to distinguish between these two processes. For this purpose rape seedlings were grown 10 d in a system which separated roots from soil by a fine-meshed screen. As a function of distance from the plane root layer formed on the screen, pH, titratable and exchangeable acidity and NO3- and NH4-nitrogen were determined. The soil, a luvisol from loess, was supplied with no N or (NH4)2SO4 either with or without a nitrification inhibitor (DCD). The bulk soil pH remained unaffected when no N or 400 mg NH4? N kg?1 soil plus DCD was applied but it decreased from 6.6 to 5.8 without DCD. In contrast, rhizosphere pH decreased in all cases, mainly within a distance of 1 mm from the root plane only, but with gradients extending to between 2 and 4 mm into the soil. The strongest pH decrease, from 6.6 to 4.9, occurred at the root surface of plants treated with both NH4-N and DCD where most of the mineral N remained as ammonium. In this case Al was solubilized in the rhizosphere as indicated by exchangeable acidity. Total soil acidity produced in the NH4 treatment without DCD was mainly derived from nitrification compared to root released protons. However, acidification of the rhizosphere was diminished by nitrification because nitrate ions taken up by the roots counteracted net proton release. It is concluded that nitrification inhibitors may reduce proton input from ammonium fertilizers but enhance acidification at the soil-root interface which may cause Al toxicity to plants. 相似文献
110.
The amount of recycled crust in sources of mantle-derived melts 总被引:5,自引:0,他引:5
Sobolev AV Hofmann AW Kuzmin DV Yaxley GM Arndt NT Chung SL Danyushevsky LV Elliott T Frey FA Garcia MO Gurenko AA Kamenetsky VS Kerr AC Krivolutskaya NA Matvienkov VV Nikogosian IK Rocholl A Sigurdsson IA Sushchevskaya NM Teklay M 《Science (New York, N.Y.)》2007,316(5823):412-417
Plate tectonic processes introduce basaltic crust (as eclogite) into the peridotitic mantle. The proportions of these two sources in mantle melts are poorly understood. Silica-rich melts formed from eclogite react with peridotite, converting it to olivine-free pyroxenite. Partial melts of this hybrid pyroxenite are higher in nickel and silicon but poorer in manganese, calcium, and magnesium than melts of peridotite. Olivine phenocrysts' compositions record these differences and were used to quantify the contributions of pyroxenite-derived melts in mid-ocean ridge basalts (10 to 30%), ocean island and continental basalts (many >60%), and komatiites (20 to 30%). These results imply involvement of 2 to 20% (up to 28%) of recycled crust in mantle melting. 相似文献