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171.
Surles RL Weng N Simon PW Tanumihardjo SA 《Journal of agricultural and food chemistry》2004,52(11):3417-3421
Five different colored carrots were analyzed for their carotenoid profile and underwent sensory evaluation to determine consumer acceptance (n = 96). Four major carotenoids were identified and quantified by use of HPLC methods. High beta-carotene orange carrots were found to contain the greatest concentration of total carotenoids. Except for the white, all the carrots are a significant source of bioavailable carotenoids. Sensory evaluation showed the high beta-carotene orange and white carrots to be favored over the yellow, red, and purple carrots in both blind and nonblind treatments (P < 0.01). However, all the carrots were well accepted by the consumer panel. With this information, carrot growers should be encouraged to cultivate specialty carrots to provide sources of both vitamin A precursors and phytochemicals. 相似文献
172.
Many soil properties influence earthworm populations and activity. To determine which properties are of significance, a broad collection of soils was investigated. Samples from these different soils were kept bare at one site in large plots (3 Mg soil per plot) to liminate crop and weather interference and to isolate the dominating mechanisms of earthworm effects. Earthworm density, biomass, and tunnelling activity were assessed after 5 years of bare fallow. All earthworm parameters varied strongly. Earthworms increased soil respiration by their tunnelling activity, and in turn increased microbial activity and propagated the loss of organic C. Earthworm abundance ranged from 12 to 274 m-2 and was about 10 times greater than on cropped soils. The range in abundance was mainly caused by variations in the numbers of juveniles. The average soil moisture content was the only soil property among the many properties investigated that was consistently correlated with earthworm abundance and biomass. Even after 5 years of bare fallow with almost no addition of fresh plant biomass and with little water loss by plant transpiration, the earthworm population was controlled by water stress and not by food stress. We therefore conclude that high water consumption by productive crops may degrade the habitat for geophagous earthworms. 相似文献
173.
C. T. Hasler K. C. Hanson S. J. Cooke R. Tinline C. D. Suski G. Niezgoda F. J. S. Phelan D. P. Philipp 《Ecology of Freshwater Fish》2007,16(3):417-424
Abstract – A whole-lake acoustic telemetry observatory situated in eastern Ontario was used to continuously monitor the three-dimensional position of 20 largemouth bass ( Micropterus salmoides ) over a 120-h period during the winter and a separate 120-h period during the early spring. These data were used to evaluate the frequency and stability of associations among fish to provide an understanding of seasonal aggregations and the sociobiology of largemouth bass. The temporal and spatial proximity of each fish relative to the other 19 individuals was assessed and, based on our definition of spatial/temporal proximity (i.e., two fish having an average hourly position <2 m apart), associations were shown to vary among fish, as well as diurnally, daily and seasonally. Associations during the winter were found to be more stable and involved fewer fish than associations during the spring. Of those fish that formed pair aggregations during the winter and spring study periods, male–female pairs occurred more often than male–male and female–female pairs. Our analysis also demonstrated that associations occurred primarily during daylight hours, suggesting that fish may use visual cues to form these aggregations. 相似文献
174.
175.
K Sachse C Grajetzki H Pfützner R Hass 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1992,39(4):246-252
Whole-cell protein patterns generated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) were compared for 34 isolates of Mycoplasma bovis. A high degree of similarity between most of the strains was established with strain-to-strain differences mainly confined to quantitative variations of certain protein bands, particularly in the molecular weight regions of 64-68, 55 and 26 kD. Two of the isolates provided more deviating patterns. Hydrophobic membrane protein fractions of the strains as prepared by Triton X-114 phase partitioning were compared by SDS-PAGE, which confirmed some of the characteristic strain features found with whole-cell proteins. The immunoblot analysis revealed that up to 20 of the 50-55 discrete protein bands detected in SDS-PAGE patterns were recognized to be antigenic by rabbit and bovine hyperimmune sera. It is concluded that the same set of major antigens is present in all strains investigated, but amounts of individual constituents may be differing. 相似文献
176.
Mayhew PD Richardson RW Mehler SJ Holt DE Weisse CW 《Journal of the American Veterinary Medical Association》2006,228(8):1209-1214
OBJECTIVE: To determine clinicopathologic features, surgical management, complications, and long-term outcome associated with diseases of the extrahepatic portion of the biliary tract treated via choledochal stent placement in dogs. DESIGN: Retrospective case series. ANIMALS: 13 dogs. PROCEDURE: Data were obtained from medical records, and follow-up information was obtained via reexamination or telephone interview with owners or referring veterinarians. RESULTS: 10 dogs had extrahepatic biliary obstruction (EHBO), 6 as a result of pancreatitis. Two dogs had rupture of the common bile duct associated with cholelithiasis. In 1 dog, a stent was placed prophylactically after gastroduodenostomy was performed for a perforated duodenal ulcer. Nine of 13 dogs survived the perioperative period and were discharged. No recurrence of EHBO or other complications developed in the discharged dogs while the stents were in place. Median follow-up period from surgery to last owner contact was 13.3 months. In 1 dog, the stent was removed endoscopically 10 months after surgery and EHBO recurred 9 months after stent removal because of cholangitis. In 4 of 5 dogs that were discharged from the hospital, in which the fate of the stent could be confirmed and the stent was secured to the duodenal wall with absorbable suture materials, the stents were passed in the feces 1 to 11 months after surgery. CONCLUSIONS AND CLINICAL RELEVANCE: Choledochal tube stenting is an effective method of decompression of the extrahepatic portion of the biliary tract in dogs and provides a less complex alternative to traditional cholecystoenterostomy techniques in select cases. 相似文献
177.
Erysipelas was diagnosed in a layer breeder flock in Sweden in 2002. Although vertical transmission of Erysipelothrix rhusiopathiae has not been previously described in chickens, the potential of erysipelas infection to adversely affect hatching eggs was of concern. To clarify the possible impact of erysipelas on hatching eggs and their progeny, an experiment was done using 200 hatching eggs collected from the infected flock. The eggs were incubated for 21 days, and the egg shells, infertile eggs, dead-in-shell embryos, and a sample of day-old hatched chicks and blood samples from 5-day-old chicks were cultured for E. rhusiopathiae. In addition, after 28 days of grow-out, the male chickens were euthanatized and cultured for the bacterium, and the remaining female chickens were placed as a backyard flock and observed over a 4-mo period. Bacteriological test results of the above-mentioned samples were negative for E. rhusiopathiae. Mortality rates were not excessive, and no clinical symptoms of erysipelas were observed during the period of observation. The result of the investigation suggests that in layer breeder chickens, E. rhusiopathiae is not vertically or egg transmitted and that the disease outbreak in the parent stock had no adverse impact on the quality of hatching eggs in terms of increased embryo mortality. 相似文献
178.
McKeegan KD Aléon J Bradley J Brownlee D Busemann H Butterworth A Chaussidon M Fallon S Floss C Gilmour J Gounelle M Graham G Guan Y Heck PR Hoppe P Hutcheon ID Huth J Ishii H Ito M Jacobsen SB Kearsley A Leshin LA Liu MC Lyon I Marhas K Marty B Matrajt G Meibom A Messenger S Mostefaoui S Mukhopadhyay S Nakamura-Messenger K Nittler L Palma R Pepin RO Papanastassiou DA Robert F Schlutter D Snead CJ Stadermann FJ Stroud R Tsou P Westphal A Young ED Ziegler K Zimmermann L Zinner E 《Science (New York, N.Y.)》2006,314(5806):1724-1728
Hydrogen, carbon, nitrogen, and oxygen isotopic compositions are heterogeneous among comet 81P/Wild 2 particle fragments; however, extreme isotopic anomalies are rare, indicating that the comet is not a pristine aggregate of presolar materials. Nonterrestrial nitrogen and neon isotope ratios suggest that indigenous organic matter and highly volatile materials were successfully collected. Except for a single (17)O-enriched circumstellar stardust grain, silicate and oxide minerals have oxygen isotopic compositions consistent with solar system origin. One refractory grain is (16)O-enriched, like refractory inclusions in meteorites, suggesting that Wild 2 contains material formed at high temperature in the inner solar system and transported to the Kuiper belt before comet accretion. 相似文献
179.
Krista N. Adamovich‐Rippe DVM Philipp D. Mayhew BVM&S Diplomate ACVS Jeffrey J. Runge DVM Diplomate ACVS William T. N. Culp VMD Diplomate ACVS Michele A. Steffey DVM Diplomate ACVS Kelli N. Mayhew VMD Diplomate ACVS Geraldine B. Hunt BVSc MVetClinStud PhD FACVSc 《Veterinary surgery : VS》2013,42(5):572-578
180.
Philipp Olias Anne Meyer Robert Klopfleisch Michael Lierz Bernd Kaspers Achim D Gruber 《Veterinary research》2013,44(1):10
Pigeon protozoal encephalitis (PPE) is an emerging central-nervous disease of domestic pigeons (Columba livia f. domestica) reported in Germany and the United States. It is caused by the apicomplexan parasite Sarcocystis calchasi which is transmitted by Accipter hawks. In contrast to other members of the Apicomplexa such as Toxoplasma and Plasmodium, the knowledge about the pathophysiology and host manipulation of Sarcocystis is scarce and almost nothing is known about PPE. Here we show by mRNA expression profiling a significant down-modulation of the interleukin (IL)-12/IL-18/interferon (IFN)-γ axis in the brains of experimentally infected pigeons during the schizogonic phase of disease. Concomitantly, no cellular immune response was observed in histopathology while immunohistochemistry and nested PCR detected S. calchasi. In contrast, in the late central-nervous phase, IFN-γ and tumor necrosis factor (TNF) α-related cytokines were significantly up-modulated, which correlated with a prominent MHC-II protein expression in areas of mononuclear cell infiltration and necrosis. The mononuclear cell fraction was mainly composed of T-lymphocytes, fewer macrophages and B-lymphocytes. Surprisingly, the severity and composition of the immune cell response appears unrelated to the infectious dose, although the severity and onset of the central nervous signs clearly was dose-dependent. We identified no or only very few tissue cysts by immunohistochemistry in pigeons with severe encephalitis of which one pigeon repeatedly remained negative by PCR despite severe lesions. Taken together, these observations may suggest an immune evasion strategy of S. calchasi during the early phase and a delayed-type hypersensitivity reaction as cause of the extensive cerebral lesions during the late neurological phase of disease. 相似文献