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101.
利用生物信息学分析法对香蕉MaSULTR3基因家族成员进行全基因组鉴定、蛋白特性分析、分子进化树分析、启动子顺式作用元件分析以及低温胁迫下叶片转录组的FPKM值分析;其后,利用基因组数据结合RT-PCR方法克隆了'天宝蕉'(Musa spp.,AAA Group)组培苗MaSULTR3.1-2基因的ORF序列;最后,利...  相似文献   
102.
不同包装和药剂处理对冬雪蜜桃贮藏性的影响   总被引:1,自引:0,他引:1  
田世平  汪沂  徐勇  范青 《果树学报》2000,17(1):41-44
不同包装与药剂配合处理能较好地保持果实的硬度,贮藏13周后各处理组合的果实硬度比对照果分别高21.4%~59.5%。药剂和包装处理对果实的可溶性固形物含量没有明显的影响。冬雪蜜桃果心褐变主要与果实的衰老有关,GA_3和钙处理明显地减少贮藏期间果心的褐变程度。  相似文献   
103.
AIM To study whether C1q/tumor necrosis factor (TNF)-related protein 3 (CTRP3)protect vascular endothelium in rats with hyperuricemia and its potential mechanisms. METHODS An animal model of hyperuricemia was established by using male SD rats drinking 10% fructose water (n=10). The rats drinking normal water served as normal controls (n=10). After 12 weeks, the rats were given a single injection with Ad-CTRP3 or Ad-GFP. The experiment was ended at 14th day after transfection.The serum levels of uric acid and nitric oxide (NO) were evaluated. The serum contents of TNF-α and interleukin-6 (IL-6) were measured by ELISA. HE staining and TUNEL assay were used to assess the morphological changes of intima and apoptosis of endothelial cells in thoracic aorta, respectively. The mRNA levels of endothelial nitric oxide synthase (eNOS), TNF-α and IL-6 were detected by RT-qPCR. The protein levels of CTRP3 and Toll-like receptor 4 (TLR4) were determined by Western blot. RESULTS Compared with normal control group, the rats with hyperuricemia showed lower CTRP3 and higher TLR4 protein levels in the thoracic aorta (P<0.05). Hyperuricemic rats had higher serum contents of uric acid, TNF-α and IL-6 (P<0.05). Also, the intima structure disturbance of thoracic aorta, increased apoptotic rate, higher mRNA levels of TNF-α and IL-6 as well as lower mRNA levels of eNOS were observed (P<0.05). By contrast, CTRP3 over-expression decreased TLR4 protein levels, reduced inflammatory cytokines, and obviously improved the morphology and function of thoracic aorta in the rats with hyperuricemia. CONCLUSION CTRP3 protect vascular endothelium in rats with hyperuricemia maybe via down-regulation of TLR4- mediated inflammatory signaling pathway.  相似文献   
104.
XIAO Li  LIU Ping  QIN Bing 《园艺学报》2000,36(11):1928-1937
AIM To investigate the role of microRNA-142-3p (miR-142-3p) in endothelial cell apoptosis during atherosclerosis (AS) and the underlying mechanism. METHODS Human aortic endothelial cells (HAECs) were treated with oxidized low-density lipoprotein (ox-LDL). The expression level of miR-142-3p was detected by RT-qPCR. Apoptosis was determined via flow cytometry (FCM) and caspase-3 activity assay. Prediction of the binding site between miR-142-3p and 3’-UTR of Rictor mRNA was performed by bioinformatics analysis and confirmed by dual-luciferase reporter assay. RESULTS The expression of miR-142-3p was substantially up-regulated during the ox-LDL-elicited apoptosis in HAECs (P<0.05,P<0.01). Forced expression of miR-142-3p exacerbated apoptosis in HAECs whereas inhibition of miR-142-3p partly alleviated apoptotic cell death mediated by ox-LDL. Further analysis identified Rictor as a direct target gene of miR-142-3p, and Rictor knock-down abolished the anti-apoptotic effect of miR-142-3p inhibitor. Moreover, the Akt/endothelial nitric oxide synthase (eNOS) signaling pathway was found to mediate the beneficial effect of miR-142-3p inhibitor on endothelial cells apoptosis. CONCLUSION Down-regulation of miR-142-3p inhibits endothelial cell apoptosis and atherosclerotic development by up-regulating the expression of Rictor and activating the Akt/eNOS signaling pathway.  相似文献   
105.
AIM To study the effect of dihydroartemisinin (DHA) on the radiotherapy efficiency in hepatocellular carcinoma H22 cell tumor-bearing mice and the role of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway in this process. METHODS A model of H22 cell tumor-bearing mice was established. The mice was divided into model group, single radiotherapy group, 5-fluorouracil (5-FU) group, and low-, medium- and high-dose DHA groups. The body weight and tumor volume in each group were measured every other day. At the end of administration, blood was collected from the tail of the mice and the animals were killed by neck removal immediately. The synergistic effect of DHA on radiotherapy was determined, and tumor growth inhibitory rate was calculated. The degree of lymphocyte transformation and natural killer (NK) cell activity were measured by MTT, the serum levels of interleukin-2 (IL-2) and IL-4 were measured by ELISA, and the protein levels of PI3K, AKT and p-AKT were determined by Western blot. RESULTS The H22 cell tumor-bearing mouse model was successfully constructed. Compared with model group, the TGT3 (tumor growth time to reach 3 times of volume) of single radiotherapy group was remarkably increased (P<0.05), while tumor weight, lymphocyte transformation degree, NK cell activity, IL-2 and IL-4 levels, PI3K protein level and AKT phosphorylation level were remarkably decreased (P<0.05). Compared with single radiotherapy group, TGT3, EF (enhancement factor), tumor inhibitory rate, lymphocyte transformation degree, NK cell activity, IL-2 level and IL-4 level were increased with the increase in DHA dose (P<0.05), and the PI3K protein level and AKT phosphorylation level were decreased (P<0.05). CONCLUSION DHA may enhance the immunity of tumor-bearing mice by inhibiting the activity of PI3K/AKT signaling pathway, thereby enhancing the efficacy of radiotherapy.  相似文献   
106.
黄瓜花叶病毒病(CMV)是为害辣(甜)椒的重要病毒,国内外对其研究较多。通过综述CMV的株系分化、抗性遗传、分子标记、抗CMV基因工程以及抗CMV育种等方面的研究结果和报道,旨在为辣(甜)椒抗CMV育种提供参考依据。  相似文献   
107.
辣椒新品种平椒3号的选育   总被引:3,自引:0,他引:3  
何志兰 《辣椒杂志》2006,4(3):14-16
平椒3号是以自交系99101为母本,自交系9949为父本配制的早熟一代杂种。果实羊角形,青熟果深绿色,果纵径17.7cm,果肩径3.0cm,果肉厚0.25cm,平均单果质量29.5g,肉质脆嫩,辣味浓且有香味,商品性好。田间对疫病、炭疽病、病毒病的抗性明显优于猪大肠。露地栽培每667m2青椒产量为3700kg左右,适宜西北地区及四川、山西、湖南等嗜辣地区露地栽培。  相似文献   
108.
巴斯德毕赤酵母表达系统研究进展   总被引:1,自引:0,他引:1  
巴斯德毕赤酵母(Pichia pastoris)表达系统是基因工程研究中广泛使用的真核表达系统,对Pichia pastoris基因结构、载体元件以及影响外源基因表达的因素等进行了较为全面的综述.  相似文献   
109.
以大麦胚芽鞘为材料,研究了生长素吲哚乙酸(indole-3-acetic ac id,IAA)和2,4表油菜素内酯(2,4-ep ibras-sinolide,ep iBR)对胚芽鞘伸长的影响。结果表明:200μmol.L-1IAA和1μmol.L-1ep iBR在黑暗条件下均促进大麦胚芽鞘的伸长生长,而且在该过程中二者存在协同作用,但必须是在IAA之前施用ep iBR或两者共同处理时才能表现;100 mg.L-12,3,5三碘苯甲酸(2,3,5-triiodobenzoic ac id,TIBA)能抑制ep iBR诱导的胚芽鞘伸长生长,暗示IAA的极性运输是ep iBR促进大麦胚芽鞘伸长生长所必需的;内源激素分析表明,ep iBR处理后胚芽鞘内源IAA含量上升,暗示ep iBR对大麦胚芽鞘伸长的促进作用在一定程度上通过调控内源IAA的水平起作用。  相似文献   
110.
用相对定量RT—PCR方法研究大白猪和二花脸猪背最长肌中肌肉生长抑制素(Myostatin)和生肌调节因子(Myo—genin)基因表达的发育性变化并进行品种及性别间比较。研究结果表明:大白猪公猪Myostatin mRNA表达水平在20日龄时达到高峰且显著高于相同日龄二花脸公猪(P〈0.05),而二花脸公猪在45日龄时才显著升高,其他日龄品种间差异不显著。二花脸公猪和母猪出生后Myostatin mRNA表达水平均表现为上升,45日龄时达到高峰,120日龄时公母猪间差异显著(P〈0.05)。二花脸公猪与大白猪公猪Myogenin mRNA的表达发育模式基本相同,均在20日龄达到最高值,品种问差异不显著。90日龄二花脸母猪Myogenin mRNA表达水平较公猪显著下调(P〈0.05)。结果提示,猪背最长肌中Myostatin和Myogenin基因表达水平在猪出生后早期均较高,但没有出现随着日龄的增加而一直升高或降低的趋势;两种基因的表达在20日龄出现品种间差异;性成熟前后二花脸公母猪间表达有差异。  相似文献   
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