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61.
62.
Eva Schrader Silvia Wein Karsten Kristiansen Lars P. Christensen Gerald Rimbach Siegfried Wolffram 《Plant foods for human nutrition (Dordrecht, Netherlands)》2012,67(4):377-383
The aim of this study was to investigate possible blood glucose-lowering effects of plant extracts in vivo for which prior to this a peroxisome proliferator-activated receptor-γ activity in vitro was observed. The ability of extracts of winter savory, purple coneflower, buckwheat and black elder to dose-dependently activate peroxisome proliferator-activated receptor-γ was determined in a reporter gene assay in COS-1 cells. For evaluation of glucose-lowering effects in vivo, db/db mice were fed a diet containing either rosiglitazone (0.02 g/kg diet, positive control) or one of the plant extracts (0.1 and 1 g/kg diet) for four weeks. Apart from glucose, insulin, triacylglycerols, non-esterified fatty acids, cholesterol and adiponectin were determined in plasma. All plant extracts showed a dose-dependent peroxisome proliferator-activated receptor-γ-activating effect in vitro. In db/db mice none of the plant extracts exerted glucose-lowering effects at the used dosages compared to rosiglitazone. Non-esterified fatty acids, triacylglycerols, cholesterol, insulin and adiponectin in plasma were not altered by the plant extracts as well. Although dose-dependent peroxisome proliferator-activated receptor-γ activity could be shown in COS-1 cells, the experiments in db/db mice lacked to confirm any anti-diabetic effect of the plant extracts in vivo and emphasizes the importance of verifying cell culture data using an appropriate in vivo model. 相似文献
63.
Comparing denitrification rates and carbon sources in commercial scale upflow denitrification biological filters in aquaculture 总被引:2,自引:0,他引:2
H.J. Hamlin J.T. Michaels C.M. Beaulaton W.F. Graham W. Dutt P. Steinbach T.M. Losordo K.K. Schrader K.L. Main 《Aquacultural Engineering》2008,38(2):79-92
Aerobic biological filtration systems employing nitrifying bacteria to remediate excess ammonia and nitrite concentrations are common components of recirculating aquaculture systems (RAS). However, significant water exchange may still be necessary to reduce nitrate concentrations to acceptable levels unless denitrification systems are included in the RAS design. This study evaluated the design of a full scale denitrification reactor in a commercial culture RAS application. Four carbon sources were evaluated including methanol, acetic acid, molasses and Cerelose™, a hydrolyzed starch, to determine their applicability under commercial culture conditions and to determine if any of these carbon sources encouraged the production of two common “off-flavor” compounds, 2-methyisoborneol (MIB) or geosmin. The denitrification design consisted of a 1.89 m3 covered conical bottom polyethylene tank containing 1.0 m3 media through which water up-flowed at a rate of 10 lpm. A commercial aquaculture system housing 6 metric tonnes of Siberian sturgeon was used to generate nitrate through nitrification in a moving bed biological filter. All four carbon sources were able to effectively reduce nitrate to near zero concentrations from influent concentrations ranging from 11 to 57 mg/l NO3–N, and the maximum daily denitrification rate was 670–680 g nitrogen removed/m3 media/day, regardless of the carbon source. Although nitrite production was not a problem once the reactors achieved a constant effluent nitrate, ammonia production was a significant problem for units fed molasses and to a less extent Cerelose™. Maximum measured ammonia concentrations in the reactor effluents for methanol, vinegar, Cerelose™ and molasses were 1.62 ± 0.10, 2.83 ± 0.17, 4.55 ± 0.45 and 5.25 ± 1.26 mg/l NH3–N, respectively. Turbidity production was significantly increased in reactors fed molasses and to a less extent Cerelose™. Concentrations of geosmin and MIB were not significantly increased in any of the denitrification reactors, regardless of carbon source. Because of its very low cost compared to the other sources tested, molasses may be an attractive carbon source for denitrification if issues of ammonia production, turbidity and foaming can be resolved. 相似文献
64.
Urethrorectal fistulectomy in a dog, using a perineal approach 总被引:1,自引:0,他引:1
W O Whitney L A Schrader 《Journal of the American Veterinary Medical Association》1988,193(5):568-569
Using urethrography, urethrorectal fistula was diagnosed in a 3-year-old male Labrador Retriever with a 2 1/2-year history of recurrent urinary tract infection characterized by intermittent hematuria and pollakiuria. Fistulectomy was performed, and the dog recovered without complication. 相似文献
65.
Investigations on the N-metabolism and N-transport in decapitated roots Experiments were carried out on roots and bleeding sap of decapitated pumpkin plants supplied with nitrate-N to investigate the nitrogen metabolism and transport of nitrogen in relation to the time after decapitation. 1. Up to two hours after decapitation absorbed nitrate was metabolized into organically bound nitrogen. The rate at which this occurred decreased with time and subsequently the turnover was strongly depressed. 2. 30 free amino acids were detected in the bleeding sap. These amounted to 25% of the organically bound nitrogen. Amino acids of the glutamate family dominated, especially glutamine and arginine. In the course of the first hour, the relative proportion of glutamine-N increased; at the same time the total concentration of amino acids was slightly reduced. More pronounced shifts in this fraction were observed after two hours, indicating the occurrence of catabolic processes. In the root neither the total concentration of free amino acids nor the composition of this fraction was altered within the two hour period. However, the composition differed substantially from that of the bleeding sap. 3. By aid of gel filtration, compounds in the bleeding sap were detected with molecular weights from 200 to 5000 and with free NH2-groups. 4. Up to the end of the two hour period the activities of nitrate reductase, glutamate-dehydrogenase and glutamate-oxalacetate-transaminase remained almost fully functional. A slight and reversible decrease in the activity of nitrate reductase in the roots in the first half hour proved to be coincident with rising rates of nitrate accumulation and strongly decreasing rates of organically bound N accumulation. The results are discussed in relation to the interruption of carbohydrate supply to the root following decapitation. In addition, differences are pointed out between the contents of nitrogen compounds in the roots and in the bleeding sap. 相似文献
66.
This study investigated the effects on embryo growth and survival rate of feeding heavily‐fertilised spring grass, containing high levels of quickly‐degradable nitrogen, to pregnant cows. Forty‐eight lactating Holstein cows between 2 and 8 weeks pregnant were turned‐out, after a one‐week transition period onto high‐ or low‐nitrate pasture and fed a high‐ or low‐concentrate supplement. Cows grazing the High nitrate pasture had significantly higher milk and plasma urea concentrations than cows grazing the Control pasture, while cows which were fed less concentrate had a notably higher plasma ammonia. However, there was no evidence that an increased quickly‐degradable nitrogen (QDN) intake from pasture affected embryo survival or growth from 20 days onwards. This suggests that the impact of turnout on fertility mainly affects ovulation, fertilisation and/or the early embryo. 相似文献
67.
C Thacher S C Schrader S K Liu 《Journal of the American Veterinary Medical Association》1985,187(2):165-167
Osteosarcoma of the patella was diagnosed by biopsy in a 9-year-old, male dog of mixed breeding. The dog was originally examined because of intermittent lameness of the left hindlimb; there were minimal palpable abnormalities of the stifle. After the diagnosis, the owner refused further treatment for the dog. The dog was reexamined 13 months later because of a marked swelling of the stifle. The dog was euthanatized and necropsy findings confirmed the diagnosis. 相似文献
68.
S C Schrader 《Journal of the American Veterinary Medical Association》1992,200(2):208-213
Pelvic osteotomy with removal or repositioning of bone was performed as treatment for obstipation in 6 domestic shorthair cats with stenosis of the pelvic canal. Narrowing of the pelvic canal was the result of pelvic fracture or sacroiliac luxation in all cats. Tenesmus and obstipation began shortly after pelvic injury in 3 cats and 5 to 12 months after injury in the remaining cats. The duration of clinical signs ranged from 36 hours to 36 months. The duration of large intestinal obstruction influenced the outcome of surgery. Surgical widening of the pelvic canal helped eliminate signs of obstruction when signs were of less than 6 months' duration (n = 2). When signs of obstipation had continued for a longer period, and megacolon had developed, such treatment was minimally effective (n = 4). 相似文献
69.
HJ. MILLER 《EPPO Bulletin》1979,9(1):7-11
Most well–known laboratory methods which can be used in the diagnosis of fireblight, as well as more recent developments in identification, have been discussed. They vary from the use of simple culture media to the use of immunofluorescent microscopy. The use of any one method alone is not advised, but by combining methods, accurate and rapid diagnosis is possible. In order to minimize diagnostic errors, especially among less experienced workers, the use of 5 % sucrose–nutrient agar for bacterial isolation followed by serological control is recommended. For further information reference is given particularly to the procedures described by Lelliott at the first EPPO Conference on Fireblight held in 1967 at Canterbury. 相似文献
70.
Elschner M Schrader C Hotzel H Prudlo J Sachse K Eichhorn W Herbst W Otto P 《Veterinary microbiology》2005,105(2):123-129
A total of 26 rotavirus positive faecal samples of diarrhoeal foals, and 8 equine rotavirus isolates were examined. Viral RNA patterns were generated, G typing was performed by PCR, and a P[12]-specific DNA probe was developed for P typing. Furthermore, five equine rotavirus isolates were sequenced in the genomic regions coding for VP7 and part of VP4. Rotaviruses of genotype G3 P[12] were found in 22 faecal samples and G14 P[12] type could be found in 4 faecal samples. These findings confirm that in Germany G3 P[12] is the predominating type of equine rotaviruses. 相似文献