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71.
DistributionandGeneFrequcnciesofEAP,ADAandAK1intheMiaoEthnicGroupofYunnan,ChinaouJiongwenShenBinZhouLangpingZhaoLipingZhaoYonghe(DepartmentofForensicMedicine,KunmingMedicalCollege,Kunming650031)我们对居住于云南的苗族人红细胞EAP、ADA和AK1的分布进行了调查。138例苗族人血样采自云南省屏边苗族自治县民族小学的学生,各取措梢血少许,涂于干净纱布上自然晾干,制成血痕样品,低温干燥保存。按文献[3]所述方法对样品进行EAP-AK1同步电泳分型检测,对所得数据进行统计处理。本次调查所检测的EAP、ADA…  相似文献   
72.
Nasopharyngeal carcinoma (NPC) is an endemic cancer with geographic and ethnic distribution within southern China and southeastern Asia, particularly in the delta area of Pearl River in Guangdong Province, where the incidence is up to 10 to 30/100000 per year. Epidemiological studies have demonstrated that the involvement of genetic factors along with Epstein- Barr virus (EBV) infections and other environmental factors are contributing to the pathogenesis of this disease in the area with …  相似文献   
73.
The nifA gene is an important regulatory gene and its product, NifA protein, regulates the expression of many nif genes involved in the nitrogen fixation process. We introduced multiple copies of the constitutively expressed Sinorhizobium meliloti (Sm) or Enterobacter cloacae (Ec) nifA gene into both the nifA mutant strain SmY and the wild-type strain Sm1021. Root nodules produced by SmY containing a constitutively expressed Sm nifA gene were capable of fixing nitrogen, while nodules produced by SmY containing the EC nifA gene remained unable to fix nitrogen, as is the case for SmY itself. However, transfer of an additional Sm nifA gene into Sm1021 improved the nitrogen-fixing efficiency of root nodules to a greater extent than that observed upon transfer of the EC nifA gene into Sm1021. Comparative analysis of amino acid sequences between Sm NifA and EC NifA showed that the N-terminal domain was the least similar, but this domain is indispensable for complementation of the Fix-phenotype of SmY by Sm Ni  相似文献   
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为了研究枯水期鄱阳湖子湖泊轮虫休眠卵空间分布的差异, 于2015年1月份, 在鄱阳湖南矶山湿地自然保护区的南深湖和白沙湖2个子湖泊进行取样调查。研究发现, 不同生境类型中轮虫休眠卵的密度具有显著差异(P<0.05), 轮虫休眠卵的分布具有明显的梯度性, 在洲滩植被区、泥滩区和积水区中轮虫休眠卵的密度逐渐减少。南深湖植被区中轮虫休眠卵的密度最高, 为(3.34±1.28) ind./cm3, 茭白中密度高达5.45 ind./cm3。不同水生植被生境中轮虫休眠卵的密度趋势为: 挺水植物>洲滩植物>浮叶植物>沉水植物。不同水深区轮虫休眠卵的分布不具有明确的规律性。此外, 研究还发现轮虫休眠卵的密度与底泥的软硬程度具有一定相关性, 泥质越软, 轮虫休眠卵的密度越低。  相似文献   
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The liver proteome can serve as a reference to better understand both disease mechanisms and possible therapeutics,since the liver is an important organ in the body that performs a large number of tasks.Here we identify the organelle proteome of C57BL/6J mouse liver nuclei as a promising strategy to enrich low abundance proteins,in the sense that analysis of whole liver cells is rather complex for current techniques and may not be suitable for proteins with low abundance.Evaluation of nucleus integrity and purity was performed to demonstrate the effectiveness of the optimized isolation procedure.The extracted nuclear proteins were identified by 2-DE MS analyses,and a total of 748 proteins were identified.Bioinformatic analyses were performed to demonstrate the physicochemical properties,cellular locations and functions of the proteins.  相似文献   
78.
我们先前通过全基因组扫描发现lp36与体重指数显提示性连锁(LOD=2.09)。肿瘤坏死因子受体2(1NFR2)定位于lp36,是肥胖的一个极好的图位和功能侯选基因。本研究采用数量传递连锁不平衡检验在两个大的独立的白人样本中进行了TNFR2基因与肥胖表型的连锁与关联检验。第一组受试者由来自79个多代家系的1836个个体组成;第二组受试者由来自157个核心家庭的636个个体组成。所检测的肥胖表型包括体重指数、脂肪量和脂肪量百分数。在多代家系中我们发现TNFR2基因变异与BMI显著连锁(P=0.0056)。结果表明,TNFR2基因是影响白人BMI变异的一个数量性状位点。  相似文献   
79.
1982年夏,我们在海南岛万宁县东澳公社的大洲岛上,承当地渔民协助,采到一种金丝燕标本。经鉴定,是我国未曾报道过的,可生产食用燕窝的  相似文献   
80.
Insight problem solving is characterized by mental impasses,states of mind in which the problem solver does not know what to do next.Although many studies have investigated the neural correlates of insight problem solving,however,the question when mental impasses occur during insight problem solving has been rarely studied.The present study adopted high temporal resolution ERPs to investigate the temporal dynamics of an impasse underlying insight problem solving.Time locked ERPs were recorded associated with problems with impasses(PWI) and problems without impasses(POI).The problem types were determined by participants’ subjective responses.The results revealed an early frontocentral P2 was linked with the preconscious awareness of mental impasses and a P3a was associated with fixed attention when the impasse formed.These findings suggest the impasse may occur initially at a relatively early stage and metacognition plays an important role in insight problem solving.  相似文献   
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