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The results of a study of the streptococcal fibrinolysin reaction and its inhibition by sera containing specific antibody are presented. It was possible to devise a quantitative antifibrinolysin test by controlling the various factors influencing the reaction. In man, the antifibrinolysin response was found to vary according to the strain of streptococcus responsible for the infection.  相似文献   
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Feeding pelteobagrus fulvidraco in cyclic-water tank with six different feeds over aperiod of sixty days.The results are shown as follows1.The frequency of occurrence of the foods on the stomach of pelteodagrus fulvidracocomplete feedI,I,Sliver carp meat>pond-snail meat,pig meat>mud-fish meat,complete feed II.Inthe case of the growth,similar changes arenoticed.2.After feeding,the protease and diastase activities of stomach and intestine show asignificant rising(p<0.05).3.The oxygen consumption rate of pelteobagrus fulvidraco is144mg/h.kg,and increases by 13.8%than before trial,suffocation point is0.309mg/l(p>0.05).  相似文献   
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日照长度对三类唐菖蒲开花,生长的效应   总被引:4,自引:2,他引:2  
张效平  高勇 《园艺学报》1992,19(4):367-370
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油桐早实丰产技术研究报告   总被引:1,自引:0,他引:1  
油桐早实丰产技术的研究是“七五”国家科技重点攻关项目。项目要求从1986年至1990年的5年内完成油桐丰产试验林面积2000亩,从第三年开始亩产桐油2-3kg,进入盛果期亩产桐油20-25kg。经6年的努力,实际完成丰产林面积2037.5亩,超额1.7%。从1988年至1991年4年累产桐油89932.8kg,连同林地间种总收入是582208.6元,扣除科研投资30万元(地方资助5万元),盈余28万元。丰产林产生的辐射效应,带动农户造桐林1万余亩。每亩多增收30元,则有30万元。油桐早实丰产技术研究,不仅为油桐生产提供应用技术,并且也直接创造了经济效益。本课题所营造的丰产林获得成功的关键技术是实现了栽培良种化,应用立地类型划分的方法。正确选择宜桐林地,合理调整林分结构,运用生态系统的理论和方法,集约化经营好桐林,这是丰产的保证。同时在试验研究的全过程中,贯彻执行了正确的科研指导思想和技术路线。  相似文献   
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Background: Sheep is important in the socio-economic lives of people around the world. It is estimated that more than half of our once common livestock breeds are now endangered. Since genetic characterization of Nigerian sheep is still lacking, we analyzed ten morphological traits on 402 animals and 15 microsatellite DNA markers in 384 animals of the 4 Nigerian sheep breeds to better understand genetic diversity for breeding management and germplasm conservation. Results: Morphological traits of Uda and Balami were significantly (P < 0.05) higher than Yankasa, which were both higher than West African Dwarf (WAD) sheep. Stepwise discriminant analysis showed tail length, rump height, chest girth, ear length and chest depth as the most discriminating variables for classification. Mahalanobis distances show the least differentiation between Uda and Balami and the largest between WAD and Balami sheep. While 93.3% of WAD sheep were correctly assigned to their source genetic group, 63.9% of Yankasa, 61.2% of Balami and 45.2% of Uda were classified correctly by nearest neighbour discriminant analysis. The overall high Polymorphism Information Content (PIC) of all microsatellite markers ranged from 0.751 to 0.927 supporting their use in genetic characterization. Expected heterozygosity was high for all loci (0.783 to 0.93). Mean heterozygote deficiency across all populations (0.171 to 0.534) possibly indicate significant inbreeding (P < 0.05). Mean values for FST , FIT and FIS statistics across all loci were 0.088, 0.394 and 0.336 respectively. Yankasa and Balami are the most closely related breeds (DA = 0.184) while WAD and Balami are the farthest apart breeds (DA = 0.665), which is coincident with distance based on morphological analysis and population structure assessed by STRUCTURE. Conclusions: These results suggest that within-breed genetic variation in Nigerian sheep is higher than between-breeds and may be a valuable tool for genetic improvement and conservation. The higher genetic variability in Yankasa suggests the presence of unique ancestral alleles reflecting the presence of certain functional genes which may result in better adaptability in more agro-ecological zones of Nigeria. These genetic characteristics are potentially useful in planning improvement and conservation strategies in Nigerian indigenous sheep.  相似文献   
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