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81.
[目的]探讨利用rDNA-ITS及其ITS2二级结构进行紫芝栽培新品种武芝2号(原名紫芝S2)的分子鉴定.[方法]通过第一代和第三代测序技术分别获得武芝2号的ITS序列,针对灵芝属(Ganoderma spp.)相关种类的ITS序列构建系统进化树进行分子分类鉴定,采用rDNA-ITS及相关引物序列进行BLAST比对分析...  相似文献   
82.
为了克隆鹅生长激素基因并表达其重组蛋白质,采集生长期鹅垂体组织,并利用TRIzol快速提取的总RNA为模板,反转录为c DNA。根据鹅生长激素基因编码的成熟肽序列(Gen Bank号:AY149895.2)设计1对引物,分别在上、下游引物的5'端引入Nhe I和Hind III酶切位点。经反转录扩增获得鹅生长激素基因的编码的成熟肽全序列。通过双酶切和连接将鹅生长激素编码区插入原核表达载体pRSET-A的Nhe I和Hind III位点之间,构建重组表达质粒pRSET-g GH并转化大肠杆菌表达菌株BL21(DE3)。转化的菌株经IPTG诱导后表达重组鹅生长激素蛋白质,分子量约为2.93×104。经过DEAE-650M弱阴离子交换树脂纯化获得较高纯度的重组鹅生长激素蛋白质。  相似文献   
83.
为了将山核桃击压姿态调整至最佳,以提高手剥山核桃的碎壳品质,提出了一种基于机器视觉与山核桃图像特征的山核桃头尾检测方法。运用数学形态学等方法,提取山核桃图像的外轮廓、纹理、大小等特征,结合山核桃的几何尺寸与纹理分布建立数学模型,进行山核桃头尾位置的检测,从而得到姿态调整的角度,为后期自动化击压加工山核桃提供了便利。  相似文献   
84.
AIM: To investigate the genes differential expression in cortex during rat focal cerebral ischemia.METHODS: cDNA microarray chips containing numerous cDNAs were used to investigate the gene expression pattern between samples of focal cerebral ischemia and sham-control operation rats. RESULTS: Two hundred and eleven genes differentially expressed were screened out, among these genes, up-and down-regulated genes were 199 and 12, respectively. CONCLUSIONS: The analysis of gene expression pattern of focal cerebral ischemia based on cDNA microarray can realize high-throughput screening of the genes associated with the focal cerebral ischemia. The differential expression of genes may be related to the pathogenesis of focal cerebral ischemic diseases.  相似文献   
85.
以曙箣竹为研究材料,通过不同光照条件下盆栽曙箣竹的生长状况及生理指标分析,探讨光照对曙箣竹生长及观赏形态的影响。研究结果表明:(1)在温室全光照下曙箣竹新增叶量达到最大值,为11片,25%遮光下增量最少仅有3片;在50%光照条件下曙箣竹的平均主秆增长量较大为4.48 cm,25%遮光下增长量最低为1.63 cm;(2)叶片叶绿素总量、叶绿素a、叶绿素b质量分数均随遮光强度的增加而增长,以25%光照叶绿素总量、叶绿素a、b为最高,分别为全光照处理的106.3%、101.9%、110%;叶绿素a/b比值下降,以25%遮光降幅最大,与对照差异显著;(3)随着时间的延长,50%光照下SOD活性呈先增大后减小的现象,25%光照和全光照的SOD活性均呈逐渐增大;50%光照和全光照的POD活性变化呈现相反的现象,前者逐渐减小,后者缓慢增加,25%光照下则是先增大后减小。综合测定指标与观察结果显示:当光照强度为50%不仅促进曙箣竹的生长还有利于观赏性的表达。  相似文献   
86.
针对南方设施中型西瓜[Citrullus lanatus (Thunb.) Matsum. et Nakai]主栽品种易裂果、贮运性差的缺点,通过品种生育期、植物学性状、果实性状、产量、抗病性等指标,对5个耐裂西瓜品种进行了比较研究,结果表明,甬蜜6号耐裂、品质佳、产量高、抗病性强,可以满足南方设施中型耐裂西瓜品种需求,适合南方设施中型西瓜轻简化设施栽培。  相似文献   
87.
黄靛牛肝菌子实体营养成分分析评价   总被引:6,自引:3,他引:6  
测定了黄靛牛肝菌子实体的氨基酸、矿质元素以及维生素等主要营养成分含量,并与香菇和双孢蘑菇的营养成分进行了比较。结果表明,黄靛牛肝菌子实体富含蛋白质、多种维生素和矿物质,并含有18种游离氨基酸,其中包括人体必需的8种氨基酸,其铅、镉、砷含量均在国家规定的食品安全标准范围之内。  相似文献   
88.
AIM:To study the role of microRNA-219 (miR-219) in regulation of transforming growth factor-β receptor type 2 (TGFBR2) in renal fibrosis. METHODS:The renal fibrosis patients (n=70) were selected in this stu-dy, and 20 cases of healthy people were selected as control group. RT-qPCR was used to detect the expression of miR-219 in the serum of the patients with renal fibrosis and control group, and the expression of miR-219 in NRK49F cells after stimulation with angiotensin Ⅱ(AngⅡ) was detected. The protein expression of α-smooth muscle actin (α-SMA) in the NRK49F cells transfected with miR-219 mimics after stimulation with AngⅡ was determined by Western blot. The potential target gene TGFBR2 of miR-219 was screened and verified by the method of luciferase reporter gene. RT-qPCR and Western blot were used to detected the effect of miR-219 mimics on the expression of TGFBR2 at mRNA and protein levels, and the mRNA expression of α-SMA, connective tissue growth factor (CTGF), type I collagen α1 (COL1A1) and COL3A1 in the NRK49F cells was also detected, respectively. The unilateral ureteral occlusion (UUO) mouse model was established and the expression of miR-219 in the renal tissue was monitored. The morphological change of renal fibrosis was observed in the UUO mice after injection of miR-219, and the mRNA expression levels of COL1A1 and COL3A1 were detected. RESULTS:The expression level of miR-219 in the patients with renal fibrosis was significantly lower than that in control group, and the expression of miR-219 in the UUO mice was decreased significantly (P<0.01). The expression level of miR-219 was significantly decreased in the NRK49F cells after AngⅡ stimulation, and miR-219 mimics inhibited the protein expression of α-SMA(P<0.01). miR-219 mimics had a targeted regulatory effect on TGFBR2 gene, which inhibited the mRNA and protein expression of TGFBR2. miR-219 mimics inhibited the mRNA expression of α-SMA, CTGF, COL1A1 and COL3A1. miR-219 also down-regulated the mRNA expression of COL1A1 and COL3A1 in the UUO mice and inhibited the process of renal fibrosis. CONCLUSION:miR-219 inhibits the development of renal fibrosis by inhibiting the expression of TGFBR2, which may become a new target for the diagnosis and treatment of renal fibrosis.  相似文献   
89.
AIM: To investigate the possible role of endothelin(ET-1) in asthma pathogenesis and the effect of atrial natriuretic factor (ANF) on changes of ET-1. METHODS: Measuring the contents of endothelin-1(ET-1),atrial natriuretic factor(ANF),cGMP in plasma and bronchoalveolar lavage fluid (BALF) of guinea pigs. RESULTS: The contents of ET-1, ANF and cGMP in asthma group were higher than that of the control group; There was a significant negative correlation between ET-1 and ANF( r=-0.638,P <0.05) in plasma of the asthma group, and a significantly negative correlation between ET-1 and ANF( r=-0.921,P <0.01) in BALF of the asthma group. There was a significantly positive correlation between ANF and cGMP( r=0.848,P <0.01) in plasma of the asthma group,and a significantly positive correlation between ANF and cGMP ( r=0.831,P <0.01) in BALF of the asthma group. The levels ET-1 in the asthma+rat ANF(rANF) group were lower than those in the asthma group,and the levels of cGMP in the asthma+rat ANF(rANF) group were higher than those in the asthma group after ceasing to infuse rANF for guinea pigs for 30 minutes.CONCLUSION: ET-1 might play an important role in the pathogenesis of asthma.ANF might inhibit production of ET-1.  相似文献   
90.
葫芦砧木低温处理鉴定方法研究   总被引:1,自引:0,他引:1  
对2个具有低温抗性差异的葫芦砧木A12、A05及西瓜TRM进行低温处理,试验结果表明,葫芦幼苗(0.43~0.71)的低温抗性显著高于西瓜(1.0),4℃条件下A12的耐低温性高于A05,6℃条件下相反;3叶期2个砧木间冷害指数差异显著,且叶绿素含量变化均达极显著,叶绿素含量变化程度与冷害指数具有显著正相关(R2=0.65),因此,叶绿素含量可以作为耐低温葫芦砧木材料选择的一个标准,且3叶1心期6℃为相对较好的低温处理条件。  相似文献   
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