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991.
992.
猪流行性腹泻病毒ORF3和M基因的克隆与序列分析 总被引:2,自引:0,他引:2
为了解福建省猪流行性腹泻病毒(Porcine epidemic diarrhea virus,PEDV)毒株ORF3和M基因变异情况,本研究从4个不同规模猪场发生仔猪“顽固性腹泻”疾病的病料中扩增到4株PEDV的ORF3和M基因,并进行了序列分析.结果表明:4株PEDV ORF3基因均含有675个碱基,编码224个氨基酸,与GenBank中登录的代表性PEDV核苷酸的同源性为89.7%~100.0%,氨基酸的同源性为94.7%~99.6%,其中FJPT毒株核苷酸的同源性与CV777 truncated毒株最低,仅为89.7%,FJNP毒株核苷酸的同源性与中国北方流行的CH ZKFG 11毒株最高,达100.0%.M基因含有681个碱基,编码226个氨基酸,与GenBank中登录的代表性PEDV核苷酸的同源性为94.8%~100.0%,氨基酸的同源性为94.8%~99.6%,其中FJPT毒株核苷酸的同源性与日本D89752毒株最低,仅为94.8%,FJNP毒株核苷酸的同源性与韩国CPF193、泰国毒株最高,达100.0%.4株PEDV毒株均与国内外流行强毒株的亲缘关系较近,与attenuate DR13弱毒株的亲缘关系较远. 相似文献
993.
利用RT-PCR结合RACE技术,从川乌头(Aconitum carmichaeli Debx.)花朵中克隆到1个类黄酮-3′,5′-羟基化酶基因的cDNA全长序列,全长1720bp,包含1个编码506个氨基酸的开放阅读框,命名为Ac-F3′5′H(GenBank登录号:JN635708)。序列分析表明Ac-F3′5′H编码的氨基酸序列中包含有已确定的保守基序,包括CYP基序、I螺旋区和血红素结合区等。氨基酸序列比对显示Ac-F3′5′H与其它物种的F3′5′H有很高的序列相似性。以川乌头18SrRNA基因(FJ748878)为内参,通过半定量RT-PCR对Ac-F3′5′H的时空表达模式进行了分析,结果显示Ac-F3′5′H随花朵发育,表达量呈递增趋势,并且在正在开放的花朵中达到最高,而在根、茎、叶中不表达,推测该基因可能在调节川乌头蓝色花朵形成中发挥作用。 相似文献
994.
Protective effect of quercetin on ER stress-related apoptosis induced by thapsigargin in macrophages
AIM: To investigate the effects and possible mechanisms of quercetin (Que) on endoplasmic reti-culum stress (ERS)-related apoptosis induced by thapsigargin (TG) in RAW264.7 cells. METHODS: ER stress of RAW264.7 cells were induced by TG at concentration of 1 μmol/L for 24 h. After treated with different concentrations of Que (80, 120 and 160 μmol/L), the cell viability was determined by MTT assay.The apoptotic rate and the changes of intracellular Ca2+ concentration ([Ca2+]i) were determined by flow cytometry, and the cell apoptotic morphology was observed under laser scanning confocal microscope.The protein levels of glucose-regulated protein 78 (GRP78) and C/EBP homologous protein (CHOP) were detected by Western blotting. The effect of Que on GRP78 and CHOP induced by TG with phosphatidylinositol 3-kinase (PI3K) inihibitor LY294002 at concentration of 15 nmol/L was measured by Western blotting. RESULTS: Que suppressed ER stress-related injury induced by TG in RAW264.7 cells. Compared with TG group, the cell viability increased (P<0.05), apoptotic rate and [Ca2+]i decreased (P<0.05) and the changes of apoptotic morphology were alleviated. The increase in GRP78 and CHOP induced by TG as an ER stress marker was suppressed by Que (P<0.05). The suppressive effect of Que on GRP78 and CHOP was reproduced by LY294002 (P<0.05), but they failed to exhibit additive suppression. CONCLUSION: Que suppresses the ER stress induced by TG in RAW264.7 cells. The protective effect may be related to its suppression on PI3K signaling pathway. 相似文献
995.
HUANG Yi HU Jian-da ZHENG Jing LI Jing WEI Tian-nan ZHENG Zhi-hong CHEN Ying-yu 《园艺学报》2012,(1):70-75
AIM: To study the effects of baicalin on CA46 cell xenografts in nude mice. METHODS: The nude mice with CA46 cell xenografts were treated with drugs via intraperitoneal injection daily, and were divided into 5 groups: negative control group, 15 mg/kg baicalin group, 30 mg/kg baicalin group, 60 mg/kg baicalin group and 4 mg/kg etoposide (VP-16) positive control group. After 12-day treatment, the weight of CA46 cell xenografts stripped from some nude mice in the 5 groups was used to evaluate the effect of baicalin on xenograft growth in the nude mice. The apoptosis, necrosis and pathological changes of the xenograft cells were examined under light microscope and transmission electronic microscope respectively. The expression levels of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway-related proteins extracted from xenografts were determined by Western blotting. The other nude mice with CA46 cell xenografts in the 5 groups continued to be treated with the drugs until death in order to evaluate the effect of balcalin on survival time of the nude mice with CA46 cell xenografts. RESULTS: Baicalin remarkably inhibited the growth of CA46 cell xenografts, induced apoptosis and necrosis of xenograft cells, and reduced the protein expression of phospho-Akt (p-Akt), nuclear factor-kappa B (NF-κB), mammalian target of rapamycin (mTOR) and phospho-mTOR (p-mTOR) in the xenografts after 12-day treatment. Furthermore, baicalin prolonged the survival time of the nude mice with CA46 cell xenografts in a dose-dependent manner. CONCLUSION: Baicalin inhibits the growth and induces apoptosis of CA46 cell xenografts in the nude mice, and prolongs the survival time of the nude mice with CA46 cell xenografts through the mechanism of down-regulating PI3K/Akt/NF-κB and PI3K/Akt/ mTOR signaling pathways. 相似文献
996.
利用叶缘光滑无裂刻的大白菜[Brassica campestris L. ssp. pekinensis(Lour)Olsson]材料‘Z16’和叶缘深裂的白菜型油菜(Brassica campestris L. var. yellow sarson Prain)‘Yellow Sarson 143’构建的120 个株系的BC2DH 群体及已构建的包含10 个连锁群的遗传图谱,利用JoinMap4 软件及MQM 作图法,对叶缘裂刻性状进行QTL 定位分析。3 次重复试验中,分别在第3、10 号染色体上的相同位置各检测到1 个控制叶缘裂刻性状的QTL,具有重复性。各QTL的LOD值在7.66 ~ 18.99 间,可解释26.4% ~ 44.7%的表型变异。通过大白菜与拟南芥注释基因比对,生物活性赤霉素(GA1、GA4)合成的关键基因BrGA20ox3位于第10 染色体的QTL 区域,对143 施加外源赤霉素GA3 能明显抑制叶缘裂刻表型,因此BrGA20ox3为控制叶片裂刻的可能候选基因。对BrGA20ox3 克隆测序获得与该基因共分离的特异标记(BrIDlobe-2),对进一步研究叶缘裂刻性状及分子标记辅助育种具有重要的意义。 相似文献
997.
AIM: To study the changes and correlations of β-catenin, multidrug resistance-associated protein 2 (MRP2), P-glycoprotein (P-gp), Bcl-2 and the free ATP level in esophageal squamous-cell carcinoma (ESCC) cell line EC-109 induced by ATP-competitive glycogen synthase kinase(GSK-3) inhibitor 6-bromoindirubin-3'-oxime (BIO). METHODS: The methods of flow cytometry, immunofluorescence, cytochemistry and ATP assay were used to study the expression levels of MRP2, P-gp, β-catenin and Bcl-2, the efflux capability of ATP-binding cassette (ABC) transporters, and the free ATP level in ESCC cells. RESULTS: After induced by BIO, up-regulation of β-catenin and Bcl-2 expression in cytoplasm and accumulation of β-catenin in nucleus were found in ESCC cells. The expression of MRP2 was up-regulated in cytoplasm and cell membrane. On the contrary, the expression of P-gp was down-regulated in cytoplasm and cell membrane. The free ATP level and the efflux capability of ABC transporters increased in ESCC cells. CONCLUSION: The multidrug resistance of ESCC cells in enhanced by BIO treatment. 相似文献
998.
AIM: To study the protective role of 14-3-3γ in burn or LPS-induced myocardial injury. METHODS: The rat model of burn or LPS-induced injury was established. The heart functions and 14-3-3γ protein expression were detected 3 h, 6 h, 12 h and 24 h after treatment. Primary neonatal rat cardiomyocytes were used in vitro. pFLAG-14-3-3γ plasmid was constructed and transfected into the cardiomyocytes 24 h before LPS-induced injury. The injury in the cardiomyocytes was evaluated by measuring the cell viability and the level of lactate dehydrogenase(LDH). Apoptosis of cardiomyocytes was detected by flow cytometry. Opening of mitochondrial permeability transition pore (mPTP) was also determined by Ca2+-induced swelling of isolated myocardial mitochondria. RESULTS: The expression of 14-3-3γ was elevated following the burn or LPS-induced myocardial injury in vivo. In vitro, transfection with pFLAG-14-3-3γ plasmid in to the cardiomyocytes significantly protected against LPS-induced injury. Compared with the cardiomyocytes without transfection with pFLAG-14-3-3γ plasmid, higher cell viability rate and lower LDH release, cell apoptosis and mPTP opening were observed in the cardiomyocytes transfected with pFLAG-14-3-3γ plasmid. CONCLUSION: The 14-3-3γ protein protects the heart against burn or LPS-induced injury by inhibiting the mPTP opening. 相似文献
999.
林火行为的研究与RS、GIS、GPS、林火数学模型、信息网络、数据库、计算机图形学、虚拟现实等技术密切相关,近些年来,这些技术的发展以及其集成化,使得对林火的研究从二维表达方式,再到如今的三维可视化表达,经过了一个又一个阶段.林火蔓延模拟与可视化的研究趋势是注重真实再现三维虚拟森林景观、多用户参与快速决策和网络信息服务等方面.文章以林火模型的发展、林火模拟系统的实现、以及与之相关的可视化技术的发展、林火模拟的实例几点为框架,对如今虚拟景观下林火蔓延三维可视化技术的研究状况和趋势进行了概述. 相似文献
1000.
甜菜碱对育肥猪生长性能和PRKAG3基因相对表达量的影响 总被引:1,自引:0,他引:1
为了研究甜菜碱对育肥猪生长性能和PRKAG3基因表达量的影响,试验采用单因子试验设计,选用80 kg左右的健康杜长大三元杂交猪60头,随机分成4组,每组3个重复,每个重复5头猪,在日粮中添加甜菜碱0,500,1 000,1 500 mg/kg,试验期为41 d,试验结束后随机选择(每组随机选择3头)12头猪进行屠宰测定。结果表明:与对照组相比,日粮中添加甜菜碱对育肥猪的日增重、日采食量、料重比均有明显影响,可以不同程度地提高日增重和采食量,降低料重比,其中以添加1 500 mg/kg甜菜碱(4组)的效果最为明显;日粮中添加甜菜碱可以不同程度地提高育肥猪PRKAG3基因的表达量,其中以1 500 mg/kg甜菜碱(4组)的效果最为明显。说明甜菜碱可以提供甲基供体,节约蛋氨酸和胆碱,从而提高育肥猪的生长性能。 相似文献