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111.
光亲和标记鉴定玉米根脱落酸结合蛋白 总被引:1,自引:0,他引:1
光亲和标记鉴定玉米根脱落酸结合蛋白吴忠义,陈珈,朱美君(北京农业大学生物学院,100094)关键词结合蛋白;光亲和标记;ABA;受体;微粒体脱落酸(ABA)作为一大类植物激素,在高等植物的生长发育以及对逆境的适应过程中发挥着重要作用。在探讨激素作用的... 相似文献
112.
Substance budgets of an upland catchment: the significance of atmospheric phosphorus inputs 总被引:1,自引:0,他引:1
1. Precipitation inputs and outflow stream outputs are presented for 1993 in an upland lake and catchment system on the Antrim Plateau, Northern Ireland. 2. Phosphorus, potassium, chloride and possibly sulphate behaved conservatively inputs were approximately balanced by outputs. Combined nitrogen outputs were very much less than inputs, whereas there was a net export of calcium, magnesium, sodium and silica from the catchment. 3. Precipitation phosphorus inputs (22 kg P km?2yr?1) are compared with literature data and are shown to be near the median value. 4. The phosphorus budget is discussed in relation to the fact that there are few oligotrophic lakes in Northern Ireland. It is suggested this is due to the rainfall inputs, low phosphorus retention by the catchment and rapid flushing rates in the lakes. 相似文献
113.
广西十万大山植绥螨三新种(蜱螨亚纲:植绥螨科) 总被引:1,自引:0,他引:1
本文记述了从广西十万大山采用的植绥螨科3新种:广西盲走螨,似沿海盲走螨和三角钝绥螨。本文描述中的测量长度单位为μm,模式标本保存于广东省昆虫研究所。 相似文献
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117.
PSⅡ反应中心D1蛋白的小肽抗体的制备和鉴定 总被引:7,自引:3,他引:4
用人工合成的PSⅡ反应中心D1蛋白中(229~240)的12肽,与牛血清白蛋白偶联后做为抗原免疫家兔, 获得抗菠菜D1蛋白抗体. 免疫双扩散法测得其具较高的效价,蛋白印迹检测结果显示该抗体仅与D1蛋白有免疫亲和反应. 表明此抗体可作为检测D1蛋白及其光抑制时降解产物的探针. 相似文献
118.
以双引物法对葡萄糖异构酶(GI)基因进行定点突变,将突变体基因于大肠杆菌中表达,获得了GI双点突变体GIK253RA198C.研究K253R和A198C双点突变对GI的结构和性质的作用,结果表明GIK253RA198C的热稳定性明显下降,最适反应温度降低5℃.文章从结构和机制上解释了为何同是K253R突变,对SM33 GI和密苏里游动放线菌GI的热稳定性产生不同的影响,认为这是由于Lys253在两种GI结构的位置上存在微小差异,从而使引入的Arg对亚基间的相互作用产生了相反效应所引起. 相似文献
119.
To reveal how the matching models of the left ventricle and its afterload affect the pressure and flow in the aortic root, the differences between the measured pressure and flow waveforms and those determined by three kinds of matching model were compared. The results showed that, compared with the results by both matching models 1 and 2, the pressure and flow waveforms determined by matching model 3 established in this work were in the closest agreement with the corresponding experimental waveforms, therefore indicating that matching model 3 was a matching model that closely and rationally characterized the match between the left ventricle and the systemic artery. 相似文献
120.
Construction of a trivalent candidate Shigella vaccine strain with host-vector balanced-lethal system 总被引:1,自引:0,他引:1
A trivalent liveShigella vaccine candidate FSD01 against S.flexneri 2a, S.sonnei and S.dysenteriae I was constructed. This candidate strain was based on the S.flexneri 2a vaccine T32. By homologous recombination exchange, the chromosomalasd gene of T32 was site-specifically inactivated, resulting in the strain unable to grow normally in LB broth, while anotherasd gene of S.mutans was employed to construct an Asd+ complementary vector. This combination ofasd
- host/Asd+ vector formed a balanced-lethal expression system in T32 strain. By use of this system, two important protective antigen
genes coding for S.sonnei Form I antigen and Shiga toxin B subunit were cloned and expressed in T32, which led to the construction of trivalent candidate
vaccine FSD01. Experimental results showed that this strain was genetically stable, but its recombinant plasmid was non-resistant.
Moreover, it was able to effectively express trivalent antigens in one host and induce protective responses in mice against
the challenges of the above threeShigella strains. 相似文献