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71.
月季切花乙烯受体ETR1 cDNA克隆及其序列分析*   总被引:6,自引:0,他引:6  
 根据乙烯受体基因ETR1 保守区设计引物, 分别以瓶插寿命差异显著的月季切花品种‘德克萨斯’和‘维亚蒂’为材料, 通过RT-PCR 从花瓣中扩增出了797 bp 的cDNA 片段, 它编码265 个氨基酸。测序和序列分析表明,‘德克萨斯’重组质粒中插入片段的核苷酸序列之间完全相同, 命名为pRT-ETR1。而‘维亚蒂’所获得的重组质粒中插入片段的核苷酸和氨基酸序列之间存在差异, 同源性分别为85. 2 %和92. 1 % , 分别命名为pRV-ETR1-V4 和pRV-ETR1-V5。pRV2 ETR12V5 的核苷酸和氨基酸序列与‘德克萨斯’pRT2 ETR1 的同源性均达99 %以上; pRV-ETR1-V4 中的核苷酸和氨基酸序列与‘德克萨斯’pRT-ETR1 的同源性分别为85. 0 %和92. 5 %。上述插入片段与桃、苹果、天竺葵、拟南芥等植物的ETR1相应区域高度同源, 其氨基酸同源性均大于90 %。  相似文献   
72.
AIM:To investigate the distribution and clonality of TCR Vβ subfamily T cells in cord blood. METHODS:The CDR3 of TCR Vβ 24 subfamily genes were amplified in mononuclear cells from 13 cases of cord blood. To observe the usage of TCR Vβ repertoire, the PCR products were further labeled with fluorescent and analyzed by genescan technique for the CDR3 size, to evaluate clonality of the detectable TCR Vβ T cells. Peripheral bloods from 10 cases of normal individuals and T cell line Molt-4 and Jurkat served as controls. RESULTS:Only 38.78%±16.26% of 24 Vβ subfamily T cell were selectively expressed in cord blood, predominantly in Vβ 3, 5, 8, 9 and 13, whereas all 24 Vβ subfamilies could be detected in T cells from peripheral blood of normal individuals. Genescan analysis showed that all PCR products of TCR Vβ subfamilies from cord blood or normal individual peripheral blood displayed multi-peaks. CONCLUSION:Some TCR Vβ subfamily T cells were absent in cord blood. All TCR Vβ subfamily T cells in cord blood displayed polyclonality.  相似文献   
73.
AIM:To examine the effect of external counterpulsation(ECP) on renin-angiotensin system(RAS) and hemodynamics in dogs with myocardial ischemia and their relationship. METHODS:Acute myocardial ischemia was induced by occluding the left anterior descending of the dogs. The local renin activity, angiotensin Ⅱ(AngⅡ) level, angiotension-converting enzyme(ACE) activity were tested by biochemical methods and hemodynamics was recorded by a 8-channel physiological recorder.RESULTS:Ischemia could actiivate renin,ACE and AngⅡ in cardiovasculature and ECP reduced them except for renin in ischemic myocardium. Ischemia also could activate RAS in lung and kidney, which play an important role on circulating RAS, and ECP reduced them. Furthermore, ECP could improve hemodynamics and there existed a close relationship between local AngⅡlevel and hemodynamics. CONCLUSION:ECP can reduce local RAS and improve hemodynamics in dogs with myocardial ischemia, which might be one of mechanisms underlying the protective effect of ECP on ischemic myocardium.  相似文献   
74.
AIM:To investigate the effect of Se-containing spirulina phycocyanin (Se-SPC) on liver injury of mice induced by carbon tetrachloride (CCl4). METHODS:The mouse model was conducted by intragastric feeding with 2% CCl4 oil for three times, meanwhile Se-SPC, spirulina phycocyanin (SPC) and Na2SeO3 were injected (ip) to various groups for 7 days. Then selenium (Se), glutathione peroxidase (GPx), superoxide dismutase (SOD), alanine aminotransferase (ALT), malondiaoldehyde (MDA) and nitric oxide (NO) levels in blood and liver were measured. RESULTS:The level of Se,GPx and SOD activities were obviously higher(P<0.05)but ALT activity,MDA and NO2-/NO3- levels were remarkably lower(P<0.05)in Se-SPC treated groups than those in CCl4 groups,and effects of high dose Se-SPC on Se,GPx,MDA and NO2-/NO3- were even more significant(P<0.01).Under the same dose of Se or protein,effects of all selected targets in Se-SPC groups were more efficient than those in SPC groups and inorganic-Se groups.Furthermore,Se levels had a positive correlation with GPx activity(r=01705),which had negative correlation with levels of MDA,NO2-/NO3- and ALT(r=-0.629,r=-0.336,r=-0.457,respectively), and positive correlations between ALT activity and MDA or NO2-/NO3- level were found (r=0.519,r=0.641). CONCLUSION:These results indicated that Se-SPC may attenuate liver injury of mice induced by CCl4 through its anti-inflammatory action and enhancing selenoenzyme expression.  相似文献   
75.
AIM: The purpose of the present study was to explore the relationship between interleukin-6 mRNA expression and endometriosis. METHODS: Using the rat model, IL-6 mRNA expression in the endometrium was examined by RT-PCR. RESULTS: The expression of IL-6 mRNA in control rats did not change at 2, 4, 6 and 8 weeks after sham operation (P>0.05), but in model rats it gradually increased at 2, 4, 6 and 8 weeks after endometriosis (P<0.01). The expression of IL-6 mRNA in uterine endometrium with endometriosis was lower than in endometriotic tissue, but higher than in endometrium from healthy controls. CONCLUSION: The IL-6 mRNA expression may contribute to the development of endometriosis . The increase in IL-6 mRNA expression may promote the implantation and growth of endometriotic tissue.  相似文献   
76.
The abnormality of the central noradrenergic system in Alzheimer's disease has two cases: decrease or increase. The former is easy to be understood, because it is resulted from the outstanding forfeit of the noradrenergic neurons in the nucleus locus ceruleus (nLC); but the noradrenalin concentration does not change and enen increase, it seems to disagree with the loss of the noradrenergic neurons in the nLC. This article put emphasis on it, enumerated the related evidence and analyzed the possible causes. At present time, the drugs to increase noradrenalin is used mostly in clinic. This paper summarized it and put forth our own opinions.  相似文献   
77.
78.
 根据普通生物学和血清学特性,长豇豆病毒病的病原被鉴定为黑眼豇豆花叶病毒(Blackeye cowpea mosaic virus,Bl CMV)、豇豆蚜传花叶病毒(Cowpea aphidborne mosaic virus,CABMV)和黄瓜花叶病毒(Cucumbermosaic virus,CMV)。  相似文献   
79.
棉疫病菌elicitin基因的克隆与序列分析   总被引:1,自引:0,他引:1  
 棉疫病菌是我国棉花和苎麻疫病的主要病原菌,引起棉花烂铃、死苗,苎麻叶斑和茎腐,严重影响棉花和苎麻的产量和品质[1,2],该菌的主要寄主有棉花、苎麻和构树[3]。  相似文献   
80.
中国栽培平菇的酯酶同工酶分析   总被引:14,自引:0,他引:14  
采用电泳技术对我国大规模栽培的64个平菇商业菌株进行酯酶同工酶分析。结果表明,我国栽培平菇菌种多样性丰富,64个菌株有44个酶谱类型,不同菌株有各自特有的酯酶同工酶酶谱。聚类分析表明,供试菌株在60%相似水平上分为6大类:第一类包括以白黄侧耳为代表的21个菌株;第二类包括以德国引进菌株为代表的6个未定种名菌株;第三类包括7个白黄侧耳与佛罗里达侧耳杂交的杂交种及4个未定种名菌株;第四类包括以佛罗里达侧耳为代表的5个菌株;第五类包括以糙皮侧耳为代表的14个菌株;第六类包括以肺形侧耳为代表的7个菌株。  相似文献   
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