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101.
根据A蛋白夹心酶联免疫吸附法(PAS-ELISA)试验结果可以将我国分离的16个黄瓜花叶病毒(CMV)分离物及4个CMV标准毒株(Fny、Lny、M、WL)区分为2个血清组.14个分离物及标准毒株Fny、M属DTL血清组,2个分离物及标准毒株Lny、WL属ToRS血清组 相似文献
102.
以厦门城市绿化为范本,通过实地调查,统计厦门城市绿地中的观赏草资源种类,结果显示目前主要有44种观赏草被应用于厦门城市绿地中。从园林应用和形态学角度出发,把这些观赏植物按株高的不同分为高型(>180 cm)、中高型(90~180 cm)观赏草及矮型(60~90 cm)、低矮型(<60 cm)观赏草2个大类,分析和总结了这2类观赏草在园林绿地中的应用方式、景观形式及其中的应用思路,并以此为基础,提出其他的应用建议,为今后城市绿地更好利用观赏草资源提供借鉴与参考。 相似文献
103.
抗日本血吸虫单克隆抗体的建立及特性测定 总被引:3,自引:1,他引:3
用感染日本血吸虫尾蚴的小鼠脾脏,制备单克隆抗体(McAb),获得24株抗日本血吸虫单抗,选择12株进行Ig亚型测定,对血吸虫抗原敏感性和特异性的测定,组织定位,免疫印迹,体外ADCC对血吸虫童虫的杀伤效应和体内被动免疫转移试验等方面的研究。其中一株IgM单抗在Balb/c小鼠体内诱导了38.41%的减虫率;另一株IgG#-1单抗在昆明系小鼠体内诱导了32.23%的减虫率,并观察到有抑制宿主肝脏肉芽肿形成的现象。 相似文献
104.
105.
针对产品族设计中核心模块演进问题,研究了产品族核心模块演进规律与演进过程评价,提出了一种模块演进规律分析与评价方法。该方法研究了客户需求与产品核心模块设计之间的关系,并在现有产品核心模块基础上,进一步对模块部件的标准化、继承性等指标进行了分析;在需求分析过程中,建立了一种基于贝叶斯网络的核心模块演进分析模型,利用历史数据对该模型进行了训练,将客户需求作为证据对该模型进行推理,进而得出核心模块在设计与工艺方面的改变规律;在演进规律分析基础上,对现有核心模块部件设计参数、标准部件重用度进行了分析,获得了核心模块演进过程综合评价值。最后,用小型轮式装载机后车架模块的演进过程验证了该方法的可行性和正确性。 相似文献
106.
Each species is characterized by a specific set of chromosomes, which is described as the chromosome portrait or karyotype. In general, such a karyotype is the same for all individuals in the population. An exception to that rule has recently been found in the orchid Erycina pusilla, which has been reported to have two cytotypes with chromosome numbers of 2n = 10 and 2n = 12. Here, we examined the karyotypes of the two cytotypes and found differences in arm ratios and heterochromatin patterns as well as in the presence of satellite chromosomes and in the number and location of rDNA and telomeric repeat sites. These differences are extensive and would have required multiple chromosome rearrangements to generate the differences between the two karyotypes. We also found that F1 hybrids between the parents with the two different chromosome numbers resulted in sterile offspring, in accordance with our previous findings. The combination of hybrid sterility and extensively rearranged chromosomes supports the hypothesis that these two reported cytotypes are, in fact, two different species. 相似文献
107.
Genetic variation in Eucalyptus camaldulensis and E. tereticornis for early growth and susceptibility to the gall wasp Leptocybe invasa in China 总被引:1,自引:0,他引:1
The gall wasp Leptocybe invasa is a major insect pest on plantation Eucalyptus in many countries. Since appearing in China in 2007 it has had major impacts on commercial plantations—some commonly planted Eucalyptus varieties have proven particularly susceptible, including hybrids involving Eucalyptus camaldulensis and E. tereticornis parent species. Intra-specific variation within each species for L. invasa susceptibility was examined in two seed source and family trials in southwest of Guangdong. The E. camaldulensis trial included 101 seedlots representing five natural stand and six seed orchard sources which also represented three sub-specific taxa. The E. tereticornis trial included 143 seedlots representing 11 natural stand and four seed orchard sources, including breeding seed orchards in China. Both trials were assessed for susceptibility to L. invasa along with height at age 9 months. Sub-specific taxa within E. camaldulensis differed significantly (P < 0.01) in L. invasa susceptibility but not height or survival; subsp. acuta had the lowest average susceptibility and subsp. simulata and obtusa were of intermediate susceptibility whilst material of uncertain sub-specific taxa from India had the highest average susceptibility. In E. tereticornis regions of origin and seed sources within regions differed significantly (P < 0.01) for both L. invasa susceptibility and height; the region China (all somewhat improved sources) had both the best average height growth and lowest susceptibility whilst the region Australia (all natural stand sources) proved inferior to China for both average susceptibility and height. A strong significant correlation was found between seed source average L. invasa susceptibility and annual rainfall at seed source geographic origin in E. tereticornis (r = ?0.873; P < 0.01), implying that seedlots from higher rainfall environments are markedly less susceptible to L. invasa. The equivalent parameter in E. camaldulensis was also strong (r = ?0.730) though not significant, perhaps due to having only five data points available. Differences between families within seed sources for both L. invasa susceptibility and height growth were also highly significant (P < 0.01) with the former trait proving moderately to strongly heritable (h i 2 = 0.54 ± 0.40 in E. camaldulensis; 0.52 ± 0.50 in E. tereticornis). Height had low to moderate heritability in both species (h i 2 = 0.11 ± 0.15 and 0.26 ± 0.08 respectively). Tree height and L. invasa susceptibility showed a moderate negative (favourable) genetic correlation in E. camaldulensis (?0.33 ± 0.64) and a moderate to strong negative (favourable) genetic correlation in E. tereticornis (?0.47 ± 0.31). Corresponding phenotypic correlations, though significant, were somewhat weaker (?0.16 and ?0.29 respectively), indicating a trend for taller trees to have lower levels of L. invasa susceptibility. 相似文献
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110.
蔗糖是植物体内重要的能量载体,也是人类食品加工的重要原料。近些年人们在蔗糖代谢的生理学、生物化学、分子生物学等领域取得了很多研究成果。主要针对近些年高等植物蔗糖的合成、转运和降解等代谢过程进行归纳和总结,期望能为今后利用生物工程手段提高植物体内的蔗糖含量提供帮助。 相似文献