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631.
用原核表达系统表达猪戊型肝炎病毒ORF2蛋白N端的主要抗原表位区。通过对GenBank公布的猪戊型肝炎病毒DQ1株ORF2的氨基酸序列进行分析,确定了其N端抗原性较高的区域,针对此区域设计并合成了1对特异性引物,RT-PCR扩增该区段,并将此片段克隆到原核表达载体pET30a(+)上,命名为pET30a-ORF2N,转化大肠杆菌BL21感受态细胞,1.0 mmol/LIPTG37℃诱导表达。RT-PCR扩增得到424 bp的片段,重组蛋白大小约为21.8 ku,与预期大小相符。West-ern blotting分析结果表明,该蛋白能与阳性血清发生特异性反应,证明该蛋白具有生物学活性。猪戊型肝炎病毒ORF2蛋白N端主要抗原表位区在大肠杆菌中成功表达,具有一定的反应原性,为进一步用其建立诊断方法奠定基础。 相似文献
632.
PENG Shu-bin ZENG Hua QIU Jian-guang HU Cheng HUANG Wen-tao LI Ke WANG De-juan 《园艺学报》2017,33(1):7-12
AIM: To analyze the difference of endonuclease domain containing 1 (ENDOD1) expression between benign prostatic hyperplasia (BPH) tissues and prostate cancer (PCa) tissues and to investigate the effect of ENDOD1 on the biological function of human prostate cancer cells. METHODS: The BPH samples (n=20) and PCa samples (n=21) were processed and analyzed according to the instruction of immunohistochemical (IHC) staining. The mRNA and protein levels of ENDOD1 in the normal prostate epithelial cells and prostate cancer cells were evaluated by RT-qPCR and Western blot, respectively. The recombinant plasmids pCMV-N-Flag-ENDOD1 was constructed and was transfected into the human prostate cancer cells. The proliferation, apoptosis, migration and invasion abilities of the prostate cancer cells were evaluated by MTT assay, flow cytometry, Transwell migration and Matrigel invasion assays, respectively. RESULTS: The analysis of variance of the immunoreactivity score showed that PCa tissues with high Gleason score displayed significantly lower ENDOD1expression than that with low Gleason score and BPH (P<0.05). The expression of ENDOD1 at mRNA and protein levels in PC3 cells and DU145 cells was significantly lower than that in the LNCap cells (P<0.05). The proliferation of DU145 transfected with ENDOD1 was inhibited. The flow cytometry indicated that ENDOD1 over-expression in the DU145 cells resulted in a notable increase in G0/G1 phase arrest (P<0.05), but the apoptotic rates showed no statistical difference. The results of Transwell assay showed that migration and invasion abilities of the cells were also inhibited after transfection with over-expressing ENDOD1 plasmid (P<0.05). CONCLUSION: The expression of ENDOD1 significantly decreased in prostate cancer with high Gleaon score. Meanwhile, the ENDOD1 is specifically down-regulated in androgen independent prostate cancer (AIPC) cell lines. Over-expression of ENDOD1 remarkably inhibits the proliferation, migration and invasion abilities of AIPC. 相似文献
633.
Nucleotide‐binding and oligomerization domain (NOD)‐like receptors in teleost fish: Current knowledge and future perspectives
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Liang Zhang Zhuying Gao Li Yu Bo Zhang Jing Wang Jun Zhou 《Journal of fish diseases》2018,41(9):1317-1330
Nucleotide‐binding and oligomerization domain (NOD)‐like receptors (NLRs) are a group of intracellular pathogen recognition receptors (PRRs) that play key roles in pathogen recognition and subsequent activation of innate immune signalling pathways. Expressions of several NLR subfamily members, including NOD1, NOD2, NLR‐C3, NLR‐C5 and NLR‐X1 have been reported in many different teleost fish species. These receptors are activated by a variety of ligands, including lipopolysaccharides (LPS), peptidoglycans (PGN) and polyinosinic‐polycytidylic acid [Poly(I:C)]. Synthetic dsRNA and bacterial or viral infections are known to stimulate these receptors both in vitro and in vivo. In this review, we focus on the identification, expression and function of teleost NLRs in response to bacterial or viral pathogens. Additionally, NLR ligand specificity and signalling pathways involved in the recognition of bacterial or viral stimuli are also summarized. This review focuses on current knowledge in this area and provides future perspectives regarding topics in need of additional investigation. Understanding the response of innate immune system to bacterial or viral infections in diverse species could inform the development of more effective therapies and vaccines. 相似文献
634.
【目的】克隆蓝叶虫微孢子虫RPB1(RNA聚合酶II大亚基)基因片段,对其基因及编码的蛋白序列特征进行生物信息学分析,进一步明确蓝叶虫微孢子虫的分类学地位,为深入探究RPB1基因编码蛋白的具体生物学功能奠定基础。【方法】根据家蚕微孢子虫RPB1基因序列,采用Primer Premier 5.0软件设计6对同源引物,利用PCR技术克隆蓝叶虫微孢子虫RPB1基因片段;通过 GSDS、SMART、DNAstar、MEGA4.1等生物信息学分析软件对蓝叶虫微孢子虫RPB1基因片段进行系统发育分析。【结果】克隆得到了蓝叶虫微孢子虫RPB1基因片段序列,在GenBank登录号为KJ728831。该基因片段的长度为2 933 bp,包含一个长为2 922 bp的开放读码框,预测编码的蛋白质由974个氨基酸组成,蛋白分子量为109.38 kD,等电点为7.087。蓝叶虫微孢子虫RPB1基因片段结构为单外显子结构,编码的蛋白含有4个结构域:RPOLA_N、RNA_pol_Rpb1_4、RNA_pol_Rpb1_5和RNA_pol_Rpb1_6。其中,RPOLA_N结构域在原核和真核生物中都是非常重要的结构域。该蛋白质的二级结构主要由4种形式组成:α螺旋、无规则卷曲、延伸链和β转角。α-螺旋和无规则卷曲所占比例相当高,延伸链主要位于α-螺旋和无规则卷曲之间。N-末端以α-螺旋的形式存在。多序列比对与系统进化分析发现,蓝叶虫微孢子虫和Nosema bombycis、N. trichoplusiae、Nosema sp. CPP、N. fumiferanae、N. disstriae、N. tyriae、N. granulosis 7种Nosema属微孢子虫聚类在同一进化支。蓝叶虫微孢子虫RPB1基因编码的蛋白与同一进化支上的其他7种微孢子虫RPB1基因编码的蛋白相似度在81.9%-99.6%,分化度在0.004-0.049。蓝叶虫微孢子虫与N. bombycis的RPB1基因序列相似性高达99.6%,并与N. bombycis具有非常近的亲缘关系。【结论】成功克隆了蓝叶虫微孢子虫RPB1基因片段,对其系统进化分析进一步证实了蓝叶虫微孢子虫确实属于Nosema属。 相似文献
635.
采用形态和生理生化鉴定方法及26S rDNA D1/D2区序列分析,对甘肃部分县市的17份土样中分离到的29株野生酵母菌株进行了鉴定.结果显示,29株酵母归为10属18个种,其中优势属为隐球酵母属(4个种),假丝酵母属(4个种),毕赤酵母属(3个种);中国新记录种7个,包括Williopsis californica,Williopsis californicavar.dimennae,Cryptococcus aerius,Candida pseudolambica,Candida fermentati,Hanseniaspora occidentalis,Pichia pijperi.同时对这29株酵母进行了抗性评价,菌株38A(Candida tropicalis)耐60%的葡萄糖,45℃高温和14%NaCl. 相似文献
636.
637.
进行了8种坡度下单个三维山体的模型风洞试验,讨论了山体各位置脉动风速谱的变化规律,以及坡度对脉动风速谱的影响.结果表明:背风面山脚0.8 h高度以下位置,脉动风速功率谱与来流风速谱相比,功率谱峰值明显增大,峰值频率向高频移动,单峰特征明显,频带变窄.除此以外的背风面其他位置、迎风面以及山顶位置的脉动风速功率谱与来流风速谱基本一致.提出了山体背风面脉动风速能量由来流湍流能量和山体尾流涡旋能量构成的思想,将来流脉动风速谱与涡旋谱进行分离,并根据试验数据拟合,提出了保守的涡旋谱的计算公式.根据不同坡度山体的试验,得出了0.5为涡旋产生与否的临界坡度. 相似文献
638.
魏本力 《上海海洋大学学报》2010,(6):859-864
处所环境是处所元经验的语义表征,在词汇语法层面主要由处所介词短语加以识解。从语言层次上看,处所环境呈现不同层次的话语模式;从语言范域上看,处所环境呈现多重范域的话语模式。处所环境的不同层次和多重范域的词汇语法呈现出复杂的语义空间。短语层面上,处所介词短语协助语义延伸,因为词汇语法将小句中的“主要事件”分派给动词来体现,而介词被降级到“次要动词”来体现“次要过程”,从而为动词语义延伸提供句法驱动力,同时处所介词短语还可营造抽象语义空间;小句层面上,处所介词短语凸显主位信息及体现小句视角,并揭示小句事件类型,同时又是主题宗旨的必要句法指向;语篇层面上,处所介词短语承担语篇组织和识别语篇类型,从而形成有“意识”的语篇空间,最终达到“社交指向”的目的。处所环境的不同层次和多重范域具有词汇语法的可识别性。处所环境的这些层次和范域研究对于其它方面的处所元经验研究有着一定的启示作用。 相似文献
639.
陈建德 《安徽农业大学学报》2010,(5):78-81
解决域名与商标权的法律纠纷的关键点,在于对级别复杂、类别多样的域名系统等复杂因素的简化。在考察域名的法律性质及域名的管理方法后,首先否定了域名的知识产权性质。从域名的法律性质入手,根据域名与商标的冲突源、冲突形态和冲突方向的不同,对纠纷的发生原因进行类型化处理。理顺了域名与商标权两者关系之后,提出诉讼和非诉讼的解决方案,在实务当中可以根据纠纷的不同原因类型对两种解决方案进行选择。 相似文献
640.
《国际水土保持研究(英文)》2022,10(4):635-648
Cultivated land quality (CLQ) is related to national food security. Rapid and high-precision monitoring of CLQ is crucial for the sustainable development of agriculture. However, current satellite image-based evaluation methods that only consider the crop's spatial spectrum characteristics in the key growth stages cannot accurately estimate CLQ. This study proposes a new method based on time-series spectral data of crop growth to improve the accuracy of CLQ estimation. This study was conducted in the Conghua District of Guangzhou, Guangdong Province, China. The results showed that seven spectral indicators were determined as the optimal indicators based on the gradient boosting decision tree (GBDT) and variance inflation factor (VIF). And the genetic algorithm-back propagation neural network (GA-BPNN) model provided more accurate CLQ estimates than the partial least squares regression (PLSR) model, indicating a nonlinear relationship between CLQ and the indicators. In addition, the GA-BPNN model with a normalized root mean square error (NRMSE) of 9.91% demonstrates the excellent potential for mapping CLQ over large areas. The model based on the seven optimal indicators of crop phenology provided higher accuracy than the GA-BPNN model based on the normalized difference vegetation index (NDVI) indicators in the spatial domain, significantly decreasing the NRMSE of the CLQ estimates by 3.17%. This further implied that the spectral indicators in the spatial frequency domain can improve the accuracy of estimating CLQ. 相似文献