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Tobey RC 《Science (New York, N.Y.)》1983,221(4609):451-452
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漳河水库由观音寺水库和鸡公尖水库通过半天然明槽相互连通组成,因受库水位观测、明槽输水计算、动库容计算误差等的复杂影响,以往多次建立的洪水预报方案均未达到可供应用的水平。在分析漳河水库入库洪水误差产生特点的基础上,通过建立抗误差产汇流预报模型和自适应实时校正技术,使漳河水库洪水预报方案平均确定性系数达91.09%,洪峰合格率达100%,峰现时间合格率达90.91%;观音寺水库洪水预报方案的平均确定性系数达90.63%,洪峰合格率达100%,峰现时间合格率达100%,终于建立了达到甲等水平的漳河水库洪水预报应用方案。 相似文献
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The effect of footrot on body weight and wool growth of sheep 总被引:1,自引:0,他引:1
Body weight and traits associated with production of wool were measured over a 2-year period between 1985 and 1987 in south-western New South Wales in a flock of Merino wethers experimentally infected with footrot. The disease was allowed to spread freely amongst 150 of the flock but kept at very low prevalence in the remaining 50 by preventive footbathing during transmission periods. Severe, underrunning footrot had a significant adverse effect on body weight, for each year of the trial. Body weight was most severely reduced at times of the year when footrot was spreading among animals and lesions were severe. The mean body weight of the infected group at the end of the 2 years of observation was 7.3 kg (11.6%) below that of the control group. Footrot also depressed wool growth, with the mean clean fleece weight of the infected group being 0.4 kg (8%) lighter than that of the controls at each of the 2 annual shearings. There were no consistent differences between the groups for the other wool characteristics measured. 相似文献
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Oil emulsion inactivated vaccine was prepared by susceptible embryos, with different strains of AEV. Four groups of normal chickens of 2 - 7 days of age were given injections for immunization, respectively. Another group was used as control. This study was expected to evaluate the immunological effect and discuss the immunological mechanism by means of five different experiments, i.e. the agar-gel precipitin test,the isolation of lymphokine, the isolation, purification and analysis of blood serum IgG, embryo-susceptibility test, and clinical and pathological examination. The results of these experiments indicated that oil emulsion inactivated vaccine is safe and effective. The chickens were normal when inoculated with AE strong virus after immunity at 4 and 37 weeks. Immunological mechanism is that the humoral immunity played an important role and celluar immunity exists, but it is not important in the process of the resistance to AEV. 相似文献
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Cell-cycle analysis in 20 minutes 总被引:32,自引:0,他引:32
Mithramycin added to mammalian cells fixed in aqueous ethanol is bound to DNA and fluoresces in direct proportion to the cellular DNA content. Quantitative fluorescence measurement by means of a high-speed flow system instrument provides a rapid method for cell-cycle analysis and for the first time permits continuous monitoring of cell-cycle kinetics during ongoing experiments. 相似文献
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在香梨 4年生幼林园内 ,进行了常规沟植、渠道内外两行树木的新梢生长量、叶片生长状况和蒸腾速率、气孔阻抗、叶温、叶温与气温差日变化的测定。结果表明 ,渠外行的各项生理指标均好于沟植和渠内行。揭示了影响树木生长的水分生理状况和过程。提出了生产中要提倡渠外行栽种香梨 ,保持沟植香梨 ,放弃渠内行栽植香梨的生产模式理论依据。 相似文献