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41.
J Jieyuan P B Spradbrow 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1992,39(5):388-390
Chickens were given various fowlpox vaccines on food pellets--a commercial vaccine (strain M), and the same strain after a single passage on chorio-allantoic membrane or in chicken embryo fibroblasts. All three oral vaccines induced antibodies at levels similar to those induced by commercial strain M administered to the wingweb. The oral vaccine derived from chorio-allantoic membrane gave protection similar to that obtained with vaccine administered by the wingweb, but this required a thousandfold more virus. 相似文献
42.
43.
J Jankela 《Veterinární medicína》1992,37(5-6):333-339
The aim of the present study is to determine the effect of different fatty acids on the amino acid catabolism judged on the level of xanthine dehydrogenase (XDH). The model system of protein depletion with subsequent repletion was used in the trial consisted of Japanese quails 71 days old. In the period of protein repletion, the fatty acid (stearic, palmitic, oleic, linolenic, linoleic and lauric, respectively) was used instead of common fatty compound in the diet. Specific activities of XDH in liver, kidneys and pancreas of quails were tested dynamically from the first to the eighth day of feeding. It was demonstrated that neither lauric, palmitic nor oleic acid, respectively, had an effect on the development of the specific activity of XDH (Fig. 3). Stearic acid as a sole fatty compound in the diet however evoked reactibility of XDH in liver or in pancreas in different way as in kidneys (Fig. 4). The dynamics of the XDH development in kidneys was practically identical than that in the control. However, XDH in liver and pancreas raised statistically already from the first day of feeding. The effects of linoleic and linolenic acids on the development of specific activity of XDH were organ selective, too (Fig. 5). XDH in kidneys was shown in the same manner as in the control group. In liver and pancreas, however, the specific activity of XDH was diminished markedly just from the first day of feeding. 相似文献
44.
Biological, physico-chemical and immunochemical methods are available today for solving the multiple problems which turn up in the course of mycotoxin diagnosis and mycotoxin research. In this review, selected analysis techniques are presented and their limits and possibilities are discussed. The biological methods (chicken-embryo-test, skin irritation test, cell cultures) indicate only toxicities, mostly without further specification for mycotoxins. In contrast, modern physico-chemical analysis (DC, HPLC, CLC, MS) allows the detection of defined mycotoxins in the picogram range; these methods should be employed or official and judicial purposes. The recently developed immunochemical methods (RIA, EIA) are characterized by a simple sample preparation, a short test duration and a high sensitivity; they could be used as a screening method in the course of mycotoxicological control of food and feed. 相似文献
45.
J. Müller 《Journal of Agronomy and Crop Science》1993,171(4):217-235
Dry Matter Production, CO2 Exchange, Carbohydrate and Nitrogen Content of Winter Wheat at Elevated CO2 Concentration and Drought Stress
Methods of mathematical modelling and simulation are being used to an increasing degree in estimating the effects of rising atmospheric CO2 concentration and changing climatic conditions on agricultural ecosystems. In this context, detailed knowledge is required about the possible effects on crop growth and physiological processes. To this aim, the influence of an elevated CO2 concentration and of drought stress on dry matter production, CO2 exchange, and on carbohydrate and nitrogen content was studied in two winter wheat varieties from shooting to milk ripeness. Elevated CO2 concentration leads to a compensation of drought stress and at optimal water supply to an increase of vegetative dry matter and of yield to the fourfold value. This effects were caused by enhanced growth of secondary tillers which were reduced in plants cultivated at atmospheric CO2 concentration. Analogous effects in the development of ear organs were influenced additionally by competitive interactions between the developing organs. The content and the mass of ethanol soluble carbohydrates in leaves and stems were increased after the CO2 treatment and exhausted more completely during the grain filling period after drought stress. Plants cultivated from shooting to milk ripeness at elevated CO2 concentration showed a reduced response of net photosynthesis rate to increasing CO2 concentration by comparison with untreated plants. The rate of dark respiration was increased in this plants. 相似文献
Methods of mathematical modelling and simulation are being used to an increasing degree in estimating the effects of rising atmospheric CO
46.
David F. Edwards DVM John W. Parker DVM J. Erby Wilkinson DVM PhD R. Gayman Helman DVM PhD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1993,7(3):169-176
Plasma cell myelomas in horses have been reported infrequently. Data from 10 cases, 9 from the literature and 1 new case, are used to characterize the disease in the horse. Hot-blooded horses (7/10), specifically Quarter Horses (4/10), were most often affected. Median age at diagnosis was 11 years (range, 3 mo-22 yr) and both male (5) and female horses (5) were represented equally. Clinical findings included weight loss (6/8), anorexia (4/8), fever (4/8), limb edema (4/8), pneumonia (3/8), rear leg paresis/ataxia (3/8), epistaxis (3/8), palpable lymphadenopathy (2/8), and bone pain (2/8). Anemia (8/8) was present routinely, and in three horses, RBCs were macrocytic. Leukopenia (2/8), thrombocy-topenia (2/8), and circulating plasma cells (3/8) were variable findings. Except for abnormal protein concentrations and hyponatremia (3), abnormal results from serum biochemical analysis including hypo-cholesterolemia (1), hypercalcemia (1), and azotemia (1) were reported infrequently. Hyperproteinemia (8/9), hypoalbuminemia (7/9), and hyperglobulinemia (8/9) were characteristic but not invariable findings. Monoclonal proteins (7/7) were detected in the α2, β, or γ region by serum electrophoresis. The paraprotein's heavy chain, determined in four horses, was a subclass of IgG. Three horses had decreased concentrations of normal immunoglobulins. Variable proteinuria (trace to 4+) was detected by routine urinalysis in four of six horses. Bence Jones proteinuria was detected in one of five horses (heat precipitation) and monoclonal proteins were detected in two of three electrophoresed urine samples. Three of the horses had lytic bone lesions detected radiographically. Bone marrow aspirates were diagnostic in two of five horses. Atypical plasma cells or increased numbers of plasma cells or both were present in histologic sections of bone marrow in six of eight horses. Common extraosseous sites of plasma cell infiltration included lymph nodes (8/8), kidney (5/8), spleen (5/8), liver (3/8), lung (3/8), brain (2/8), and orbit (2/8). Two horses had intracellular and extracellular crystalline deposits. 相似文献
47.
In this clinical study, a diaphragmatic peritoneo-pericardial hernia in an eight month-old Persian cat is reported. The diagnostic procedure is described, and the clinical symptoms and diagnostic possibilities are discussed. 相似文献
48.
Abstract. Leaching losses of nitrate-nitrogen were measured from a set of eight hydrologically isolated plots on a clay loam soil over the period from September 1987 to February 1990. Variable drainflow recovery from the plots hampered accurate estimation of nitrate loading, but results suggest that, when inorganic nitrogen fertilizer is applied up to the recommended amount, there is little influence of the amount applied on the amount leached. We did, however, observe the following effects on nitrate leaching: leguminous green manure incorporated in autumn increased leaching of nitrate-nitrogen by 10–15 kg per hectare during the winter; autumn cultivation caused some increase in leaching compared with no cultivation in one year; some systematic variations in nitrate leaching occurred between years and between plots, but were unrelated to treatments.
From the results we conclude that green manuring does not provide sufficient nitrogen for organically grown crops on this soil but contributes significantly to nitrate leaching, and that growing spring cereals, with the land remaining in stubble as long as possible in autumn, may be the best strategy to minimize nitrate leaching. 相似文献
From the results we conclude that green manuring does not provide sufficient nitrogen for organically grown crops on this soil but contributes significantly to nitrate leaching, and that growing spring cereals, with the land remaining in stubble as long as possible in autumn, may be the best strategy to minimize nitrate leaching. 相似文献
49.
50.
The technique of cystocentesis in dogs and cats was studied. The indications and contraindications of this method are discussed, using illustrations. 相似文献