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81.
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Elderly migration and development in small communities   总被引:1,自引:0,他引:1  
"This paper develops a conceptual model of the process of community change [in the United States] in response to elderly inmigration. Analysis of intra-regional variation in elderly migration patterns in Appalachia, and synthesis of an emergent literature on the benefits and costs of attracting elderly migrants, serve as a backdrop for case studies, based on field observations and interviews, of three contrasting Appalachian communities at different stages of development as retirement destinations."  相似文献   
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Abstract Extract A 15-year-old pony mare developed firm irregular bony swellings on all four legs. These were most severe around the carpal and fetlock joints of the forelegs, restricting both flexion and extension. Over about 6 months the horse had periodic bouts of coughing. She showed moderate weight loss and a depressed demeanour.  相似文献   
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Studies into the effects of the environment on health and performance of agricultural animals are of clear-cut relevance to farming practice. The theoretical and practical importance of lymphocyte transformation to any assessment of immunological reactivity under defined environmental conditions, therefore, is reported in this paper. Communicated is methodical experience obtained from isolation of lymphocytes from peripheral blood of calves, lymphocyte culturing, and morphological evaluation of lymphocyte transformation. Views are given on the suitability of the lymphocyte transformation test. The following results have been obtained: Centrifugation of defibrinated blood, using "Visotrast-370", is recommended for lymphocyte isolation. Morphological evaluation will ensure a high degree of precision when 1 x 10(6) cells in one millilitre culturing fluid are to be cultured over three days, the culturing fluid consisting of 20 per cent of autologous serum and 80 per cent of Eagle medium, antibiotics, and a portion of 1-vol.% of phytohaemagglutinin (Wellcome). The lymphocyte transformation test, for its methodical accuracy, is good enough to detect and identify environmental effects on immunological reactivity of calf. It is likely to reflect the immunological response to an antigen application.  相似文献   
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Concentrations of DDT, TDE, DDE, and sigma DDT were determined in homogenized whole fish samples of 129 northern pike (Esox lucius). These fish were netted between June 1974 and June 1975 in the first 10 km of the Richelieu River flowing in Canadian territory. Two years after the banning of DDT, sigma DDT levels ranged from 0.2 ppm fresh body weight in two-year-old specimens to 1.5 ppm in a six-year-old pike. Residues increased greatly with age, and significant seasonal variations in the sigma DDT levels were found in five- and six-year-old pike.  相似文献   
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Two sprays of vinclozolin (0.5 kg a.i. ha–1) or procymidone (0.5 kg a.i. ha–1), the first at the beginning of flowering and the second two weeks later, gave the best control ofBotrytis cinerea on dwarf snap beans (Phaseolus vulgaris). Good results were also obtained with iprodione and with thiophanate-methyl. Vinclozolin and procymidone at the same program were the most active fungicides againstSclerotinia sclerotiorum. Treatments with the latter two fungicides resulted in increased yields of pods and had no influence on colour and quality of the pods. Residue levels were below the tolerances.Samenvatting Twee bespuitingen met vinchlozolin (0,5 kg a.i. ha–1) of procymidon (0,5 kg a.i. ha–1), de eerste in het stadium begin bloei en de tweede 14 dagen later tijdens de peulzetting, waren voldoende omB. cinerea in stamslabonen te bestrijden. Tevens werden goede resultaten verkregen met iprodion en thiofanaat-methyl. Vinchlozolin en procymidon gaven volgens hetzelfde schema toegepast ook de beste werking tegenS. sclerotiorum. Toepassingen van deze laatste twee fungiciden leverden een hogere peulopbrengst en hadden geen invloed op de kleur en de kwaliteit van de peulen. Het residugehalte in de peulen lag beneden de toelaatbare grens.This research was subsidized by the Instituut tot Aanmoediging van het Wetenschappelijk Onderzoek in Nijverheid en Landbouw (IWONL).  相似文献   
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