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141.
Fat greenling (Hexagrammos otakii) is an economocally important marine fish species. Thirtyfive microsatellite loci were isolated from two enriched genomic library of Hexagrammos otakii. Ten of these loci were polymorphic in a test population with alleles per locus ranging from two to six, and observed and expected heterozygosities per locus from 0.2581 to 1.0000 and from 0.2892 to 0.7726, respectively. Four loci significantly deviated from Hardy–Weinberg equilibrium after Bonferroni correction and no significant linkage disequilibrium was found between pairs of loci. These polymorphic microsatellite loci would be useful for investigating genetic diversity of Hexagrammos otakii.  相似文献   
142.
Endoxin-mediated myocardial ischemia reperfusion injury in rats in vitro   总被引:7,自引:0,他引:7  
Myocardial ischemia reperfusion results in an increase in intracellular sodium concentration, which secondarily increases intracellular calcium via Na(+)-Ca2+ exchange, resulting in cellular injury. Endoxin is an endogenous medium of digitalis receptor and can remarkably inhibit Na+/K(+)-ATPase activity. Although the level of plasma endoxin is significantly higher during myocardial ischemia, its practical significance is unclear. This research is to investigate whether endoxin is one of important factors involved in myocardial ischemia reperfusion injury. Ischemia reperfusion injury was induced by 30 min of global ischemia and 30 min of reperfusion in isolated rat hearts. Heart rate (HR), left ventricular developed pressure (LVDP), and its first derivative (+/-dp/dtmax) were recorded. The endoxin contents, intramitochondrial Ca2+ contents, and the Na+/K(+)-ATPase activity in myocardial tissues were measured. Myocardial damages were evaluated by electron microscopy. The endoxin and intramitochondrial Ca2+ contents in myocardial tissues were remarkably higher, myocardial membrane ATPase activity was remarkably lower, the cardiac function was significantly deteriorated, and myocardial morphological damages were severe in myocardial ischemia reperfusion group vs. control. Anti-digoxin antiserum (10, 30 mg/kg) caused a significant improvement in cardiac function (LVDP and +/-dp/dtmax), Na+/K(+)-ATPase activity, and myocardial morphology, and caused a reduction of endoxin and intramitochondrial Ca2+ contents in myocardial tissues. In the present study, the endoxin antagonist, anti-digoxin antiserum, protected the myocardium against the damages induced by ischemia reperfusion in isolated rat hearts. The results suggest that endoxin might be one of main factors mediating myocardial ischemia reperfusion injury.  相似文献   
143.
Although glutathione S-transferase (GST, EC 2.5.1.18) is thought to play important roles in abiotic stress, limited information is available regarding the function of its gene in grapes. In this study, a GST gene from grape, VvGSTF13, was cloned and functionally characterized. Transgenic Arabidopsis plants containing this gene were normal in terms of growth and maturity compared with control plants but had enhanced resistance to salt, drought, and methyl viologen stress. The increased tolerance of the transgenic plants correlated with changes in activities of antioxidative enzymes. Our results indicate that the gene from grape plays a positive role in improving tolerance to salinity, drought, and methyl viologen stresses in Arabidopsis.  相似文献   
144.
首先对绵羊卵母细胞收集及其体外成熟(IVM)条件进行了摸索,然后对影响电刺激激活IVM卵母细胞的因素进行了研究,观察激活后卵母细胞在体外的发育能力。结果表明,剥离法比注射器吸卵法所获得的卵母细胞成熟率高,激活更加正常。剥离法收集的卵母细胞体外成熟培养27小时后,以含0.1mmol/L CaCl2、0.1mmol/L MgSO4和10mmol/L组氨酸的0.28mol/L肌醇(inositol)作基  相似文献   
145.
目的:分析不同产地甘草中18α-甘草酸及18β-甘草酸的含量差异,为不同产地甘草的质量评价提供参考。方法:采集7个省区12个不同产地的甘草种子,栽培于北京中医药大学药草园,一年后以其中180株甘草作为实验材料,利用内转录间隔区(ITS)序列鉴定其基原,采用高效液相色谱(HPLC)法测定其18α-甘草酸及18β-甘草酸含量,并分析其差异性及相关性。结果:ITS鉴定结果显示180株甘草样品均为乌拉尔甘草。HPLC分析结果显示,18α-甘草酸的标准曲线为y=6×10-7x-0.0029(R2=0.9982),在0.0111~0.2214μg范围内线性良好;18β-甘草酸的标准曲线为y=1×10-6x+0.0164(R2=0.9999),在0.2256~4.5120μg范围内线性良好。12个产地中山西应县甘草样品的18α-甘草酸及18β-甘草酸含量均最高,新疆尼勒克县甘草样品的18α-甘草酸及18β-甘草酸含量均最低,且所有样品中18α-甘草酸与18β-甘草酸的含量均存在显著相关关系。结论:不同产地甘草质量差异显著,本实验结果可为不同产地甘草的质量评价提供参考。  相似文献   
146.
The alpha‐proteobacteria of the genus Wolbachia is a widespread group of maternally inherited endosymbionts of arthropod and nematode hosts. Wolbachia infection induces a range of host phenotypes, including cytoplasmic incompatibility, male killing, feminization, and induction of thelytokous parthenogenesis. Heterogony (cyclical parthenogenesis) is a remarkable characteristic of oak gallwasps, Cynipini, the largest tribe of the Cynipidae. A few species of Cynipini are exceptional in that they are univoltine and exhibit thelytokous parthenogenesis, probably because they lost the arrhenotokous generation of their heterogonic ancestor species due to Wolbachia infection. In this study, the presence of Wolbachia was detected using polymerase chain reaction primers for the wsp genes in a thelytokous parthenogenetic species [Dryocosmus kuriphilus (Yasumatsu)] (Hymenoptera: Cynipidae: Cynipini). Approximately 29.8 and 87.1% of adults of the Zhuzhou and Fuzhou strains, respectively, were infected with Wolbachia while all females of the remaining four strains collected from other localities in China were Wolbachia free. The length of the wsp fragment of Zhuzhou and Fuzhou strains was found to be 573 and 561 bp, respectively. The nucleotide sequence of the bacterial wsp fragment indicated that the endosymbiotic bacteria of the Zhuzhou and Fuzhou strains are members of supergroup A, but belong to different clades; they probably originated from two independent infection events. In conclusion, thelytokous parthenogenesis of D. kuriphilus is not caused by Wolbachia infection and the deletion of the arrhenotokous generation is thus not associated with such an infection.  相似文献   
147.
体外培养小鼠巨噬细胞RAW264.7,实验分为空白组、脂多糖(LPS)组(1mg/LLPS)及脂氧素A4(LXA4)处理组(1mg/LLPS与0.1~1000nmol/LLXA4共同温育)。处理预设时间后,实时荧光定量聚合酶链反应和酶联免疫吸附实验分别检测粒细胞集落刺激因子(G-CSF)基因表达和蛋白质分泌水平,免疫印迹法检测IκBα降解和NF-κB转位情况,荧光素酶报告质粒检测NF-κB转录活性。结果表明:LPS诱导G-CSF表达(P<0.01),LXA4抑制G-CSF基因表达和蛋白质分泌,其中10nmol/LLXA4作用最明显(抑制率为39.8%)(P<0.01);10nmol/LLXA4明显抑制IκBα降解(P<0.05)、NF-κB转位(P<0.05)以及NF-κB的转录活性(P<0.05)。这提示LXA4可能通过抑制NF-κB的转位和转录活性而抑制LPS诱导RAW264.7巨噬细胞分泌G-CSF。  相似文献   
148.
目的 本研究旨在明确精氨酸甲基转移酶(PRMT)7在人骨髓间充质干细胞(hBMSCs)成脂分化过程中的变化以及是否调控hBMSCs成脂分化,进而探索相应的调控机制。方法 通过定量反转录PCR(qRT-PCR)和蛋白质印迹(Western blot)检测hBMSCs成脂分化过程中PRMT7的变化;通过qRT-PCR和Western blot实验证明PRMT7稳定敲低细胞系构建成功。进行油红O染色和定量分析,以及qRT-PCR和Western blot实验检测PRMT7稳定敲低细胞系成脂分化水平的变化;通过裸鼠体内异位成脂实验,油红O染色检测PRMT7稳定敲低细胞系体内异位成脂的效果;通过qRT-PCR和Western blot证明PRMT7稳定过表达细胞系构建成功。进行油红O染色和定量分析以及qRT-PCR和Western blot实验检测PRMT7稳定过表达细胞系成脂分化水平的变化;通过qRT-PCR和Western blot实验检测敲低PRMT7和过表达PRMT7的细胞中IGF-1表达水平的变化。在PRMT7稳定敲低细胞系中转染siIGF-1并通过qRT-PCR和Western blot检测IGF-1的表达水平验证敲低效率。通过油红O染色和定量分析,qRT-PCR实验检测转染siIGF-1的敲低组hBMSCs成脂分化水平的变化。结果 本文发现:在hBMSCs成脂过程中,PRMT7表达水平明显降低(P<0.01);敲低PRMT7后hBMSCs的成脂分化能力增强(P<0.001);敲低PRMT7后hBMSCs的体内异位成脂分化能力增强;过表达PRMT7后hBMSCs的成脂分化能力减弱(P<0.01);PRMT7敲低后IGF-1表达水平增加(P<0.000 1);PRMT7过表达后IGF-1表达水平降低(P<0.000 1);转染siIGF-1后,各细胞系IGF-1表达水平明显降低(P<0.001);敲低组转染siIGF-1后成脂分化能力明显降低(P<0.01)。结论 本研究通过细胞水平和裸鼠皮下移植实验发现PRMT7显著抑制hBMSCs成脂分化,机制研究发现PRMT7对hBMSCs成脂分化的调控作用依赖IGF-1信号通路。上述研究表明,PRMT7可能是治疗相关疾病的潜在分子靶点,为PRMT7和hBMSCs应用于相关疾病治疗提供了新思路。  相似文献   
149.
微生物絮凝剂及其产生菌的研究新进展   总被引:6,自引:0,他引:6  
介绍了近几年来国内外微生物絮凝剂及其产生菌的一些发展概况,列举了近几年一些研究较深入的胞外生物高聚物絮凝剂的物质属性和化学组成.重点讨论了胞外生物高聚物絮凝剂的成分分析、絮凝机理以及影响絮凝活性的因素,详细综述了絮凝剂产生菌的遗传学和代谢机理方面的研究进展,文章最后提出微生物絮凝剂的发展趋势和研究方向.  相似文献   
150.
半滑舌鳎性别控制和全雌育种等研究领域中迫切需要一种能够快速鉴定鱼类个体遗传性别的有效方法。文章采用AFLP技术, 利用选择性引物组合(E-ACT/M-CAA)从半滑舌鳎中筛选到一条雌性特异的AFLP标记。对该标记进行二次PCR扩增、琼脂糖凝胶回收、克隆、测序。分析表明, 序列全长为791 bp, 与GenBank中的序列无同源性。以该雌性特异AFLP标记DNA序列为模板, 设计了一对特异的PCR引物, 成功地将其转化为SCAR(Sequence characterized amplified regions)标记, 并在100尾已知性别的半滑舌鳎个体(雌雄各50尾)中进行验证, 结果表明, 该SCAR标记在所有雌性个体中均扩增得到一条长度为324 bp的DNA条带, 而在49尾雄性个体中均扩增不到该DNA条带(有1尾雄性个体例外), 证明该SCAR标记是雌性特异的, 并可用于半滑舌鳎个体遗传性别鉴定。随后, 利用该SCAR标记检测了3日龄半滑舌鳎幼苗, 结果表明, 雌性个体比例为41.7%。  相似文献   
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