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91.
Hilt P Schieber A Yildirim C Arnold G Klaiber I Conrad J Beifuss U Carle R 《Journal of agricultural and food chemistry》2003,51(10):2896-2899
The phenolic profile of strawberry fruits (Fragaria x ananassa Duch., Rosaceae) was investigated by high-performance liquid chromatography with photodiode array detection. A peak displaying retention time and UV spectral data identical to those of phloridzin (phloretin 2'-O-beta-d-glucoside), a dihydrochalcone glucoside so far considered characteristic of apples, was monitored. For further characterization, crude extracts of strawberries were purified on polyamide, and the target compound was isolated by preparative and analytical HPLC. Structure elucidation was performed on the basis of APCI- and ESI-MS in the negative ion mode as well as by 1D and 2D NMR spectroscopy using authentic phloridzin for comparison. The d-configuration of the sugar moiety was established by HPLC analysis of the corresponding acyclic 1-deoxy-1-(N-acetyl-alpha-methylbenzylamino)alditol acetate. Apart from its chemotaxonomic relevance, this first report on the occurrence of phloridzin in strawberries is of particular interest for the authenticity control of strawberry products such as juices, jams, and fruit preparations since phloridzin has so far been used for the detection of fraudulent admixtures. 相似文献
92.
Andreas Krein Merce Salvia-Castellvi Jean Francois Iffly Laurent Pfister Lucien Hoffmann 《Water, air, and soil pollution》2007,182(1-4):357-368
Runoff events were analysed in separated sewer systems in the town of Luxembourg. The relationships between Event Mean Concentrations of different pollutants and runoff patterns were evaluated. In addition, the inter-storm and intra-storm variability of the material transport were determined. Primarily, the variations in pollutant concentrations and loads are determined by the antecedent weather conditions. The presence of illicit sanitary inputs in one of the sewers produced a significant first flush effect as well as higher Event Mean Concentrations for pollutants. Furthermore, near the town of Trier 40 storms were analyzed in a small natural basin mainly influenced by runoff from a separated sewer system. Natural and artificial storm events were investigated in order to estimate the relationship between the pollutant sources in the channel and from the separated sewer system. Just like in the canalization of Luxembourg City the pollutant dynamics during natural storms are strongly influenced by pre-event hydrological conditions. The artificial storms behave differently. Despite little pre-rain, the maximum concentrations of toxic substances are comparatively low. A resuspension of sediment only occurs in the natural channel system, without the introduction of fines from the sewer system. 相似文献
93.
A Pospischil M T Stiglmair-Herb R G Hess P A Bachmann G Baljer 《Veterinary pathology》1986,23(1):29-34
The effect of rotaviruses and enterotoxigenic Escherichia coli administered in various sequences to cesarean-derived, colostrum-deprived calves was studied using light and electron microscopy. The structure of the lymphoid tissue in the ileum, the number of mitoses in the crypts, number of intraepithelial lymphocytes, and enzyme histochemistry (alkaline phosphatase, acid phosphatase, succinic dehydrogenase, beta-galactosidase, and leucinaminopeptidase) of the ileal dome epithelium were evaluated. The area of lymphoid follicles in Peyer's patches of the ileum was investigated morphometrically. Monoinfections with either rotavirus or enterotoxigenic E. coli induced a significant increase in lymphoid follicle area, but did not affect dome epithelial cells. Dual infections did not consistently affect the follicle area, but the number of intraepithelial lymphocytes and the mitotic indices exceeded those of comparable monoinfections. Changes in activity of enzymes in the ileal dome epithelial area were minor. 相似文献
94.
T Sydler A Pospischil B Gottstein J Eckert 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1991,38(2):135-141
An immunoperoxidase method using rabbit anti human Giardia lamblia serum for the demonstration of giardia in paraffin embedded intestinal animal tissue is described. Specificity was tested against other protozoal parasites. 相似文献
95.
Attaching and effacing bacteria in the intestines of calves and cats with diarrhea 总被引:10,自引:0,他引:10
Histopathologic and electron microscopic examination of intestines of three calves and two cats revealed attaching effacing bacteria characteristic of enteropathogenic Escherichia coli (EPEC) in ileum, cecum, and colon. The attaching effacing bacteria in one of the calves contained bacteriophages, and an E. coli isolate from that calf was shown to produce Shiga-like toxin. These findings contribute to emerging evidence that attaching effacing intestinal bacteria are globally distributed pathogens in a variety of host species and that bacteriophage-mediated production of Shiga-like toxin is related to the virulence of such bacteria. 相似文献
96.
97.
Droplets were released from an ‘instantaneous line source’ perpendicular to the wind at heights of 4 and 7 m above the ground. Droplets were collected by rotating samplers at three heights; sets of samplers were positioned in a line parallel to the wind, downwind of the line source. Trials were carried out in moderately unstable conditions during the day, and under stable conditions shortly after dark, both over short rough stubble and over mature cotton. A substantial proportion of the small droplets were found to travel as far as 500 m over cotton; over grass, few of even the smallest droplets were collected 250 and 500 m downwind of the line source. Collection at the distant samplers was on average slightly, but not significantly, more when the spray was released at the greater height. 相似文献
98.
99.
100.
The clinical signs, the results of haematological and biochemical analyses and the treatment of 30 cattle with botulism are described, and the signs of the 13 cattle that survived are compared with those of the 17 that were euthanased owing to the disease. The cattle originated from 11 farms that had experienced an outbreak of botulism. The most important clinical sign in all the cattle was a reduction in the strength of the tongue; excessive salivation and difficulty in swallowing were observed in 20 of the animals, and the ears of 15 of them drooped. In 21 of the cattle, reaction to pricking of the head and body with a hypodermic needle was either absent or slight. Twelve of the animals had an unsteady, slow, difficult gait, and nine were unable to stand. A significantly higher proportion of the cattle which were euthanased had marked changes in behaviour and condition, anorexia, severely reduced skin turgor, weak tongues, a low rectal temperature, a high heart rate and a low blood pH; 11 were euthanased immediately after a clinical examination and six were euthanased one to five days after the initiation of treatment because their condition had deteriorated. Thirteen of the animals were treated for three to 23 days and were healthy when they were discharged. The treatment consisted of an intravenous infusion of 10 to 20 litres of glucose saline per day and the daily administration of fresh ruminal juice. Follow-up by telephone several months later revealed that all 13 animals had recovered completely. 相似文献