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61.
为揭示2003年在王朗采集的鼢鼠标本王03001号是否为秦岭鼢鼠四川兽类新纪录,以鼢鼠标本王0300号的肌肉组织为研究材料,运用PCR技术对其线粒体Cyt b基因进行克隆和测序.结果表明该基因的长度为1140bp,编码380个氨基酸的蛋白质,所编码的蛋白质含有2个N-糖基化位点,1个蛋白激酶C磷酸化位点,4个酪蛋白激酶Ⅱ磷酸化位点,6个N-豆蔻化位点.再以已研究的鼢鼠6个种18个体Cyt b基因序列及氨基酸序列为基础数据,把中华竹鼠(Rhizomys sinensis)作为外群,结合本研究的结果构建系统发育树,所得结果不支持王03001号标本为秦岭鼢鼠.  相似文献   
62.
基于嵌入式Linux的Web远程继电器控制系统的设计实现   总被引:1,自引:0,他引:1  
介绍了一种运行在嵌入式Linux平台下的以Web模式远程控制系统的实现方式.对硬件系统架构进行了介绍.以uCLinux操作系统为软件平台,对Boa Web服务器进行配置,然后编写相应的CGI程序响应用户输入,操作底层硬件寄存器,从而达到远程控制的目的.  相似文献   
63.
Prochlorococcus is a marine cyanobacterium of global significance. Two ecotypes are adapted to either high-light (HL) or low-light (LL) conditions. The ratio between chlorophyll (Chl) a and b is a distinguishing characteristic of these two ecotypes. However, how this ratio evolved in Prochlorococcus during this ecotype differentiation remains unclear. Our analyses reveal that the ancestor of Prochlorococcus was typically low-light adapted. The LL ecotype showed a stagnant evolution, and the HL ecotype was recently diverged. There was an adaptive radiation after directional evolution in the Chl b/a ratio regulation. Recombination in chlorophyllide a oxygenase (CAO) and positive selection on Clp protease contributed to the directional evolution of Prochlorococcus. The recombinant fragments of CAO were correlated with a large group of shared coevolving sites. Evidence of positive selection was found in both subunits of Clp. Chl b/a ratio evolution, as annotated by molecular evidence, appears to be among the crucial reasons that explain how Prochlorococcus has become the dominant photosynthetic organism in the ocean.  相似文献   
64.
The key subunit Ⅱ of cytochrome c oxidase (CcO) contains a soluble binuclear copper center (CuA) domain. The CuA domain of Paracoccus versutus was cloned, expressed, purified and characterized. The gene encoding the CuA domain in pET11d vector was expressed in E. coli BL21 (DE3). The results showed that the CuA domain was expressed mostly in inclusion bodies and the CuA domain protein synthesized in E. coli cells represents approximately 10 percent of the total cellular proteins. Dissolved in urea, dialyzed and recombined with Cu+/Cu2+ and purified by the Q-sepharose fast flow anion-exchange column and Sephadex G-75 gel filtration column, the soluble purple-colored protein, which shows a single band in electrophoresis, was obtained. The UV-visible absorption spectrum of CuA domain showed that there are intense band at 478 nm and a shoulder peak at 530 nm, and two weak bands at 360 and 806 nm respectively, which can be assigned to the charge transfer and the interactions of obitals of Cu—S and Cu——Cu in the mixed-valence binuclear metal center (Cu2S2R2). The far-UV CD spectrum indicated that this domain is predominantly in β-sheet structure. The fluorescence spectra showed that its maximal excitation wavelength and maximal emission wavelength are at 280 and 345 nm, respectively.  相似文献   
65.
The excitation energy transfer efficiency between b -Car and Chla molecules in purified CP43 and CP47 was calculated by comparing absorption and fluorescence excitation after normalization at 550 nm, CP43 had an energy transfer efficiency of 29.1% while the CP47 had an energy transfer efficiency of 62.8%, proving that excitation energy was transferred between b -Car and Chla molecules in CP43 and CP47 at normal conditions. The excitation energy transfer between b -Car and Chla molecules in CP43 and CP47 may occur through the "Dexter" mechanism and the distance between these two kinds of pigments should be less than 1 nm. In addition, the results were also used to discuss the conformational relationship between b -Car and Chla molecules in CP43 and CP47.  相似文献   
66.
噻吩并吡啶并嘧啶类化合物的合成   总被引:1,自引:1,他引:0  
根据活性亚结构拼接原理,利用aza—Wittig法合成了一类未见文献报道的噻吩并吡啶并嘧啶类化合物,通过IR,^1H NMR,EI—MS分析等方法对所合成的化合物进行了结构表征。  相似文献   
67.
The gene hNGFB encoding the β subunit of human nerve growth factor (hNGF) was cloned intoP. pastoris secretive expression vector pHIL-S1 andE. coli expression vector pET-15b. The recombinant hNGFB vectors pSNGF and pET15b-NGF were transformed intoP. pastoris host cell GS115 (Mut+, His) andE. coli strain BL21 (DE3) respectively. Expression and secretion of hNGFB inP. pastoris was attempted under the direction of the AOX1 promoter and PHO1 signal sequence. The positive colonies growing on medium without histidine were further selected by PCR. The yield of rehNGFB in GS115 was about 14.4% of total cellular secretive protein. The secreted protein was immunological active on Western blotting with rabbit anti-mNGFB antibodies. The fusion protein yield of rehNGFB inE. coli BL21 (DE3) was about 10.3% of total cellular protein after IPTG induction. Western blot detection showed its immunological activity.  相似文献   
68.
使用长模板PCR方法检测 2 2 3例湖北地区人群中CYP2D6二倍体 .在被检人群中 ,CYP2D6二倍体的基因频率为 2 .7% .检测到 6例CYP2D6二倍体 ,基因型分别为 1× 2 (3/ 6 ) , 2× 2 (2 / 6 ) ; 10× 2 (1/ 6 ) .表明湖北地区人群中CYP2D6二倍体的基因频率比其他地区中国人群稍高  相似文献   
69.
应用K4b2心肺功能测定仪对日常体力活动能量消耗的测定   总被引:2,自引:0,他引:2  
应用K4b2心肺功能测定仪对日常体力活动的能量消耗进行现场测定,以期为我国体力活动指南的制定提供基础资料。选取23名北医青年学生作为受试者,其中男11名,女12名,应用K4b2心肺功能测定仪对受试者在静息、慢走(3km/h)、快走(6km/h)、慢跑(8km/h)、骑自行车(12km/h)状态下的能量消耗进行测定。各项体力活动的能量消耗及代谢当量由大到小排列,依次为慢跑((6.26±1.22)kcal.kg-1.h-1,6.0MET)、骑自行车((4.30±0.67)kcal.kg-1.h-1,4.2MET)、快走((3.75±0.73)kcal.kg-1.h-1,3.6MET)、慢走((1.24±0.26)kcal.kg-1.h-1,1.2MET)、静息((1.08±0.24)kcal.kg-1.h-1,1.0MET),按照体力活动强度分级,属于中低强度体力活动。慢走、快走、慢跑、骑自行车等日常体力活动适于在中国人群中推广。  相似文献   
70.
徐长彬 《科学技术与工程》2012,12(21):5347-5350
重点对IEEE—1394b互连系统的静态等时传输模型和动态传输模型进行了详细研究,分别得到了上述两个模型下消息的平均等待时间的数学表达式,指出了IEEE—1394b互连系统中影响实时特性的因素,并对分析结果进行了仿真。关键参数消息的平均等待时间是IEEE—1394b光纤总线互联系统实时性研究的重点。介绍了IEEE—1394互连系统实时性的特点,重点推导了等时传输和异步传输模型的消息平均等待时间的数学表达式,通过仿真得出等时传输对异步传输具有很大影响。  相似文献   
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