Dvl1及其突变体腺病毒载体的构建与在MSCs中表达鉴定

Dvl1及其结构缺失突变体ΔDIX（dsh and axin）和ΔDEP（dsh,Egl-10 and pleckstrin）腺病毒载体的构建并验证其在MSCs（mesenchymal stem cells）中的表达情况。将目的基因定向克隆至pAdTrack-CMV穿梭载体上,并经PmeⅠ线性化后在BJ5183细菌中与pAdEasy-1骨架质粒同源重组,获得重组腺病毒载体,在QBI-293A细胞中包装及扩增,实时荧光定量PCR和Western bolt验证Dvl1在MSCs中的表达情况。经PCR、PacⅠ单酶切鉴定及测序分析,成功构建Ad-Dvl1、Ad-ΔDIX和Ad-ΔDEP腺病毒载体,目的基因序列与GenBank报道一致,并选出150 MOI为最适感染MSCs的感染复数,成功构建了Ad-Dvl1、Ad-ΔDIX和Ad-ΔDEP腺病毒载体,并获得高滴度的病毒子,qPCR和Western blot证实Dvl1在MSCs中高表达并增加了β-catenin在细胞中的累积,为进一步研究Dvl1在MSCs迁移过程的作用奠定了基础。     

序贯疗法治疗圈养黑猩猩支原体肺炎一例

肺炎支原体对于灵长类幼年黑猩猩的感染,与人类幼儿的临床表现和发病规律相似。该病例幼年黑猩猩早期症状偶见咳嗽,听诊肺部有湿性罗音,体温38.3℃。初步诊断为肺炎,用抗病毒药和抗生素头孢克洛治疗无效。随着病程发展,体温进一步升高到39℃以上,几乎无食欲。拍X光片和采血做支原体抗体检测,结果显示支原体感染强阳性。最终使用阿奇霉素采取＂停4喂3＂的序贯疗法治疗,即阿奇霉素输液3d——口服5d——停药4d——口服3d——停药4d——口服3d,其他则对症治疗。动物在治疗第7天时除偶见咳嗽,症状基本消除;治疗20d后,动物恢复健康。需要注意的是,治疗过程中一定要按照序贯疗法坚持用药治疗,防止疾病复发和减小用药的副作用。     

Optimization of differentiated regional land development patterns based on urban expansion simulation—A case in China

The advancing global urbanization puts great pressure on the society and ecosystem, especially in developing countries. Reasonable land-use policies adapted to local conditions are the key issues to prevent disordered urban expansion. Multi-scenario simulation provides a new perspective for differentiated policy formulation based on regional heterogeneity. Regarding the Shaanxi Province, a rapid urbanized area with high spatial heterogeneity in western China, as the study case, we tracked its past land-use changes and predicted the characteristics of urban expansion using the Future Urban-Regional Environment Simulation model. We found that (1) during the past 35 years, built-up land evidently increased accompanied by the loss of cropland, grassland, and unused land. (2) The urban expansion mainly will occur in the areas with flat terrain under three scenarios. (3) The urban expansion will transit into the “requiring land from mountains” pattern in the future, which means that it will gradually spread to areas with higher slopes. (4) Differentiated and optimal development patterns are proposed for different subregions by accounting the loss of ecosystem service in the procedure of urban expansion. This research can help local governments formulate differentiated future macro control of territorial spatial planning to optimize subregional land development.     

欧美杂交杨Pnd-LRR3基因克隆及其抗锈菌侵染表达

为深入探究欧美杂交杨(Populus nigra×P.deltoides)感病的分子机理,以及抗病基因在发病过程中所起的作用,克隆了欧美杂交杨LRR3蛋白编码基因Pnd-LRR3。对Pnd-LRR3基因进行了生物信息学分析,并对其在抗锈菌过程中的功能进行了研究。Q-PCR结果显示,强致病性的落叶松-杨栅锈菌(Melampsora larici-populina)E4菌株接种6 h,Pnd-LRR3基因表达量上调增幅较大,168 h为显著下调。说明Pnd-LRR3基因在E4侵染过程中起到一定抗性作用,但最终无法阻止锈菌的侵染。     

Exogenous CaCl2 reduces salt stress in sour jujube by reducing Na+ and increasing K+, Ca2+, and Mg2+ in different plant organs

In this study, we investigated the effects of 10 mM CaCl₂ on membrane permeability, malondialdehyde (MDA), reactive oxygen species (ROS), and Na⁺, K⁺, Ca²⁺, and Mg²⁺ concentrations in different organs of sour jujube grown under 150 mM NaCl stress. Our results showed 73% leaf wilting in the Na treatment. The Na treatment significantly increased leaf superoxide (O₂^.?) production rates, hydrogen peroxide (H₂O₂) concentrations, cell membrane permeability, MDA concentrations, and Na⁺ concentrations in roots, stems, and leaves. The Na treatment significantly reduced K⁺, Ca²⁺,and Mg²⁺ concentrations in roots, but increased K⁺ concentrations in stems. Compared with the Na treatment, 39% of the leaves showed wilting symptoms in the Na+Ca treatment. The Na+Ca treatment significantly decreased leaf O₂^.? production rates, H₂O₂ concentrations, cell membrane permeability, and MDA concentrations. Moreover, the Na+Ca treatment (1) significantly reduced Na⁺ concentrations in roots, stems, and leaves; (2) significantly increased root K⁺ concentrations; (3) significantly increased K⁺/Na⁺ ratios in roots; (4) significantly increased Ca²⁺ concentrations in stems and leaves, and Mg²⁺ concentrations in roots. In conclusion, exogenous CaCl₂ reduces NaCl stress in sour jujube by reducing Na+ concentrations and increasing K⁺, Ca²⁺, and Mg²⁺ concentrations in various plant organs.     

油罐内浮盘密封失效原因与预防措施

针对油罐内浮盘密封失效问题逐渐凸显的现状,分析了内浮盘静、动密封与油气空间的关系,总结了油罐内浮盘密封失效的主要表现,静密封失效包括:内浮盘盖板搭接面间出现缝隙孔洞,密封胶囊或舌形密封带与内浮盘外边缘间的挟紧部位出现缝隙,防旋导管与内浮盘盖板间不密封,浮盘自动通气孔、人孔与盖板间不密封;动密封失效包括:密封胶囊或舌形密封带与罐内壁间密封性能差,量油导管与量油导管护筒盖间的密封性能差,浮盘人孔盖与人孔座间的密封性能差,防旋转钢丝绳松紧度不满足浮盘安全运行要求。基于设计、施工、使用、检修4个环节分析归纳了内浮盘密封失效的原因,提出了优化设计、控制施工质量、控制内浮盘制造安装质量、内浮盘定期检测与管理、规范检修作业等预防措施。     

危害沙棘的围连环夜蛾生物学特性及防治

围连环夜蛾在我国多有分布，但看见其幼虫的还是很少，因资料中寄主不祥，笔者经室内外观察。发现其危害多种植物的叶片，更喜欢危害沙棘树的叶片，笔者经2a的室内外观察得知。其生物学特性在辽宁西部每年1代，以蛹越夏及冬。对沙棘树危害较重，对栽植的大果沙棘危害尤为严重，在5a生的沙棘树上有100多头幼虫危害，成虫善飞翔。     

经络穴位给药系统在兽医临床上的应用

经络穴位给药系统以中医经络理论为基础,具有经穴效应和药物效应的双重治疗特性,已广泛应用于兽医临床.目前,兽医临床上常用穴位给药方式是穴位埋植和穴位注射,而常用穴位主要是后海穴、百会穴、肺龠穴.随着经络穴位给药系统的广泛应用,新型经络穴位给药制剂和经络穴位给药作用机理已成为经络穴位给药系统研究的重点.     

浅谈如何培养和提高学生英语阅读理解的能力

在大学英语教学过程中,培养和提高学生英语的阅读理解能力是非常重要的环节,但笔者在教学中发现：大多数学生的阅读能力都比较薄弱。针对这种普遍现象,作为大学英语教师应该积极探索解决方法,充分利用精读课、泛读课及选择合适的阅读材料等来激发学生阅读的兴趣,以达到快速提高英语水平的目的。     

珍稀树种香果树的利用价值及实用繁殖技术

香果树是我国特有单种属珍稀阔叶树种,属国家Ⅱ级重点保护野生植物,具有较高的推广价值。结合生产实践经验和目前有关科研进展,综合论述了香果树的开发利用价值以及关键培育技术,为开发利用香果树提供了科学理论基础。