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21.
BA Hampson JM Morton PC Mills MG Trotter DW Lamb CC Pollitt 《Australian veterinary journal》2010,88(5):176-181
Objective The aims of this work were to (1) develop a low-cost equine movement tracking collar based on readily available components, (2) conduct preliminary studies assessing the effects of both paddock size and internal fence design on the movements of domestic horses, with and without foals at foot, and (3) describe distances moved by mares and their foals. Additional monitoring of free-ranging feral horses was conducted to allow preliminary comparisons with the movement of confined domestic horses. Procedures A lightweight global positioning system (GPS) data logger modified from a personal/vehicle tracker and mounted on a collar was used to monitor the movement of domestic horses in a range of paddock sizes and internal fence designs for 6.5-day periods. Results In the paddocks used (0.8–16 ha), groups of domestic horses exhibited a logarithmic response in mean daily distance travelled as a function of increasing paddock size, tending asymptotically towards approximately 7.5 km/day. The distance moved by newborn foals was similar to their dams, with total distance travelled also dependent on paddock size. Without altering available paddock area, paddock design, with the exception of a spiral design, did not significantly affect mean daily distance travelled. Feral horses (17.9 km/day) travelled substantially greater mean daily distances than domestic horses (7.2 km/day in 16-ha paddock), even when allowing for larger paddock size. Conclusions Horses kept in stables or small yards and paddocks are quite sedentary in comparison with their feral relatives. For a given paddock area, most designs did not significantly affect mean daily distance travelled. 相似文献
22.
Antigen specificity and activity of ovine antibodies induced by immunization with Corynebacterium pseudotuberculosis culture filtrate 总被引:1,自引:0,他引:1
J A Ellis D A Hawk K W Mills D L Pratt 《Veterinary immunology and immunopathology》1991,28(3-4):303-316
Sheep were immunized three times with a vaccine composed of filtrate from a 36 h culture of Corynebacterium pseudotuberculosis and a block polymer adjuvant. Immunization resulted in the development of exotoxin-neutralizing antibody. This corresponded to the recognition of a 31.6 kDa protein on sequential immunoblots of ammonium sulfate-precipitated filtrate. In addition sera from vaccinated sheep recognized at least eight bacterial cellular antigens on immunoblots of ether-extracted C. pseudotuberculosis, including bands of 12, 25.1, 31.6, 36.3, 39.8, 63.1, 70, 75 or 79.4 kDa. Sera from these sheep altered the colony growth characteristics of C. pseudotuberculosis in vitro. These results indicate that immunization with soluble C. pseudotuberculosis in vitro. These results indicate that immunization with soluble C. pseudotuberculosis antigen preparations that have been used in toxoid vaccines induces antibody responses to numerous cellular antigens in addition to exotoxin and suggest that serologically mediated antibacterial effects could be an important component in the protection from disease that has been reported following immunization with C. pseudotuberculosis toxoids. 相似文献
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Vvedenskaya IO Rosen RT Guido JE Russell DJ Mills KA Vorsa N 《Journal of agricultural and food chemistry》2004,52(2):188-195
Flavonoids were extracted from cranberry powder with acetone and ethyl acetate and subsequently fractionated with Sephadex LH-20 column chromatography. The fraction eluted with a 60% methanol solution was composed primarily of phenolic constituents with maximum absorbance at 340 nm. A high-performance liquid chromatography procedure was developed, which resolved 22 distinct peaks with UV/vis and mass spectra corresponding to flavonol glycoside conjugates. Six new constituents not previously reported in cranberry or in cranberry products were determined through NMR spectroscopy to be myricetin-3-beta-xylopyranoside, quercetin-3-beta-glucoside, quercetin-3-alpha-arabinopyranoside, 3'-methoxyquercetin-3-alpha-xylopyranoside, quercetin-3-O-(6' '-p-coumaroyl)-beta-galactoside, and quercetin-3-O-(6' '-benzoyl)-beta-galactoside. Quercetin-3-O-(6' '-p-coumaroyl)-beta-galactoside and quercetin-3-O-(6' '-benzoyl)-beta-galactoside represent a new class of cranberry flavonol compounds with three conjugated components consisting of a flavonol, sugar, and carboxylic acid (benzoic or hydroxycinnamic acids). This is also the first report identifying quercetin-3-arabinoside in both furanose and pyranose forms in cranberry. Elucidation of specific flavonol glycosides in cranberry is significant since the specificity of the sugar moiety may play a role in the bioavailability of the flavonol glycosides in vivo. 相似文献
25.
Interactions with food components may alter the resistance of food proteins to digestion, a property thought to play an important role in determining allergenic properties. The kinetics of breakdown of the bovine milk allergen alpha-lactalbumin during in vitro gastrointestinal digestion was found to be altered by interactions with physiologically relevant levels of phosphatidylcholine (PC), a surfactant that is abundant both in milk and is actively secreted by the stomach. Breakdown during gastric digestion was slowed in the presence of PC and accompanied by small alterations in the profile of resulting peptides, with little effect being observed during subsequent duodenal digestion. alpha-Lactalbumin was found to unfold at gastric (acid) pH, giving a CD spectrum similar to that obtained for the partially folded state it is known to adopt at pH values below its isoelectric point. Fluorescence polarization studies performed at low pH indicated that this partially unfolded form of the protein was able to penetrate into the PC vesicles. These interactions are probably responsible for the slowing of gastric digestion by reducing the accessibility of the protein to pepsin. These findings show that interactions with other food components, such as lipids, may alter the rate of breakdown of food proteins in the gastrointestinal tract. It underlines the importance of the food matrix in affecting patterns of food allergen digestion and hence presentation to the immune system and that in vitro digestion systems used for assessing digestibility of allergens must take account of surfactants. 相似文献
26.
Jha P Mills A Hanson K Kumaranayake L Conteh L Kurowski C Nguyen SN Cruz VO Ranson K Vaz LM Yu S Morton O Sachs JD 《Science (New York, N.Y.)》2002,295(5562):2036-2039
We analyzed the technical basis for a major global program to reduce disease among the poor. Effective interventions exist against the few diseases which most account for excess mortality among the poor. Achieving high coverage of effective interventions requires a well-functioning health system, as well as overcoming a set of financial and nonfinancial constraints. The annual incremental cost would be between $40 billion and $52 billion by 2015 in 83 low-income and sub-Saharan African countries. Such a program is feasible and would avoid millions of child, maternal, and adult deaths annually in poor countries. 相似文献
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Hydrocortisone is necessary for the formation of rough endoplasmic reticulum in mammary alveolar epithelial cells. This membrane system is required for the synthesis of the milk protein, casein, but it is not required for the synthesis of a nonmilk protein fraction. 相似文献
29.
Ravishankara AR Turnipseed AA Jensen NR Barone S Mills M Howard CJ Solomon S 《Science (New York, N.Y.)》1994,263(5143):71-75
Hydrofluorocarbons, many of which contain a CF(3) group, are one of the major substitutes for the chlorofluorocarbons and halons that are being phased out because they contribute to stratospheric ozone depletion. It is critical to ensure that CF(3) groups do not cause significant ozone depletion. The rate coefficients for the key reactions that determine the efficiency of the CF(3) radical as a catalyst for ozone loss in the stratosphere have been measured and used in a model to calculate the possible depletion of ozone. From these results, it is concluded that the ozone depletion potentials related to the presence of the CF(3) group in hydrofluorocarbons are negligibly small. 相似文献
30.