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1. chinaXiv:201807.00038 [pdf]

S100A9参与乙型肝炎病毒X蛋白介导的HepG2细胞增殖与迁移

张秀瑜; 王玎; 杜燕娥; 武睿; 段亮
分类: 生物学 >> 生物工程

目的:探讨S100A9在乙型肝炎病毒X(HBx)介导的HepG2细胞增殖及迁移中的作用。方法:用表达HBx蛋白的重组腺病毒AdHBx感染HepG2细胞后,用CCK-8实验检测细胞增殖能力及划痕愈合实验检测细胞迁移能力;在HepG2/AdHBx细胞中转染S100A9-siRNA及其对照siRNA后,检测HepG2细胞增殖及迁移能力;在HepG2/AdHBx和对照组HepG2/AdGFP细胞中,采用Real- time PCR及Western Blot检测S100A9基因及蛋白的表达情况;在HepG2/AdHBx细胞中,加入不同剂量的NF-κB抑制剂BAY11-7082后,检测各组中S100A9的基因及蛋白表达情况。结果:HBx促进HepG2细胞的增殖与迁移;S100A9-siRNA抑制S100A9的表达后,HBx促进HepG2细胞的增殖与迁移的作用降低,HBx介导的HepG2细胞的增殖与迁移部分依赖于S100A9;S100A9基因及蛋白表达在HepG2/AdHBx中较对照组HepG2/AdGFP显著升高,HBx可致S100A9表达增加;抑制NF-κB转录活性后,AdHBx+BAY11-7082组S100A9基因及蛋白表达较对照组显著降低,阻断NF-κB转录活性可部分抑制HBx调控的S100A9表达。结论:HBx可调控S100A9的表达且与NF-κB活化有关, S100A9参与 HBx介导的HepG2细胞的增殖与迁移。

提交时间: 2018-07-11 来自合作期刊:《中国生物工程杂志》 点击量322下载量43 评论 0

2. chinaXiv:201807.00039 [pdf]

地高辛标记Ucp2 基因RNA探针的制备和应用

刘志贞; 张凯丽; 孙雨晴; 赵虹; 郝宇卉; 李美宁
分类: 生物学 >> 生物工程

目的:为了制备用于检测小鼠胚胎早期Ucp2基因表达的地高辛标记的特异性RNA探针。方法:提取小鼠胚胎脑组织总RNA,设计引物,通过RT -PCR方法获取Ucp2基因片段,将其克隆到pGEM -T载体。分别利用Sp6、T7和Ucp2特异性引物,PCR扩增获得转录模板,通过Sp6及T7 RNA聚合酶,获得地高辛标记的正义、反义Ucp2 RNA原位杂交探针。检测标记探针的效价后,通过全胚胎原位杂交分析制备探针的特异性和杂交效果。结果:成功获得Ucp2基因正义、反义探针,反义探针能高效灵敏检测到Ucp2基因在小鼠胚胎Ed9.5、Ed10.5神经系统呈现高表达,而正义探针未能检测到表达信号。结论:成功制备了特异高效的地高辛标记Ucp2 RNA 原位杂交探针,为进一步研究Ucp2基因在小鼠胚胎组织中的表达,尤其在神经组织的定位奠定基础。

提交时间: 2018-07-11 来自合作期刊:《中国生物工程杂志》 点击量338下载量43 评论 0

3. chinaXiv:201807.00066 [pdf]

华氏巨球蛋白血症相关突变MYD88 L265P新型检测体系的建立

陈弘远; 陈红岩; 乔纯; 李建勇; 卢大儒
分类: 生物学 >> 生物工程

华氏巨球蛋白血症(Waldenström’s macroglobulinemia,WM)是一种罕见的,不可治愈的淋巴浆细胞淋巴瘤(lymphoplasmacytic lymphoma,LPL)。MYD88 L265P突变在华氏巨球蛋白血症患者中检出率很高(>90%),可以用于疾病的鉴别和诊断,因此,开发一种高灵敏度的检测方法对这个突变进行检测具有较大的临床价值。通过将ARMS技术与Clamping PCR技术相结合,建立的新型MYD88 L265P突变富集检测体系可以满足这一需求。优化后,该检测体系检出限为102拷贝,灵敏度为0.1%,对19份临床样品的双盲试验中,检测结果准确率达到100%。所建立的方法具有灵敏、准确的优势,适用于华氏巨球蛋白血症的早期诊断,有较为广阔的应用前景。

提交时间: 2018-07-06 来自合作期刊:《中国生物工程杂志》 点击量205下载量23 评论 0

4. chinaXiv:201807.00032 [pdf]

Characteristics of soil organic carbon and total nitrogen under various grassland types along a transect in a mountain-basin system in Xinjiang, China

BI Xu; LI Bo; NAN Bo; FAN Yao; FU Qi; ZHANG Xinshi
分类: 生物学 >> 生态学

Soil organic carbon (SOC) and soil total nitrogen (STN) in arid regions are important components of global C and the N cycles, and their response to climate change will have important implications for both ecosystem processes and global climate feedbacks. Grassland ecosystems of Funyun County in the southern foot of the Altay Mountains are characterized by complex topography, suggesting large variability in the spatial distribution of SOC and STN. However, there has been little investigation of SOC and STN on grasslands in arid regions with a mountain-basin structure. Therefore, we investigated the characteristics of SOC and STN in different grassland types in a mountain-basin system at the southern foot of the Altai Mountains, north of the Junggar Basin in China, and explored their potential influencing factors and relationships with meteorological factors and soil properties. We found that the concentrations and storages of SOC and STN varied significantly with grassland type, and showed a decreasing trend along a decreasing elevation gradient in alpine meadow, mountain meadow, temperate typical steppe, temperate steppe desert, and temperate steppe desert. In addition, the SOC and STN concentrations decreased with depth, except in the temperate desert steppe. According to Pearson's correlation values and redundancy analysis, the mean annual precipitation, soil moisture content and soil available N concentration were significantly positively correlated with the SOC and STN concentrations. In contrast, the mean annual temperature, pH, and soil bulk density were significantly and negatively correlated with the SOC and STN concentrations. The mean annual precipitation and mean annual temperature were the primary factors related to the SOC and STN concentrations. The distributions of the SOC and STN concentrations were highly regulated by the elevation-induced differences in meteorological factors. Mean annual precipitation and mean annual temperature together explained 97.85% and 98.38% of the overall variations in the SOC and STN concentrations, respectively, at soil depth of 0–40 cm, with precipitation making the greatest contribution. Our results provide a basis for estimating and predicting SOC and STN concentrations in grasslands in arid regions with a mountain-basin structure.

提交时间: 2018-07-05 来自合作期刊:《Journal of Arid Land》 点击量144下载量37 评论 0

5. chinaXiv:201807.00033 [pdf]

Grazing every month minimizes size but boosts photosynthesis in Stipa grandis in the steppe of Inner Mongolia, China

LI Xiaobing; HUANG Qi; MI Xue; BAI Yunxiao; ZHANG Meng; LI Xu
分类: 生物学 >> 植物学

In order to explore the effects of grazing frequency on functional traits and to test whether Stipa gandis has compensatory photosynthesis during the frequent grazing period, we investigated morphological traits, biomass allocation, photosynthetic traits, and chlorophyll fluorescence parameters of the species in Inner Mongolia, China. The grazing frequency treatments included fencing (T0), grazing in May and July (T1, i.e., two months per year) and grazing from May to September (T2, i.e., continuous five months per year). Results indicate that T1 and T2 treatments did not affect individual biomass, but T2 treatment negatively affected individual size, i.e., plant height, stem length, and leaf length. Physiological traits of S. grandis were significantly affected by grazing, year, and their interaction. In July 2014 (i.e., dry environment and low relative humidity), the photosynthetic rate, transpiration rate and water use efficiency were highest under T2 treatment, which was caused by the increase in stomatal conductance. However, in July 2015 (i.e., wet environment and high relative humidity), the photosynthetic rate and water use efficiency were higher under T1 and T2 treatments, which were caused by the increase in actual quantum efficiency and stomatal conductance. Our results implied that under frequent grazing treatment, S. grandis had small height and efficient compensatory photosynthesis, which promoted its resistance to severe grazing.

提交时间: 2018-07-05 来自合作期刊:《Journal of Arid Land》 点击量137下载量32 评论 0

6. chinaXiv:201807.00034 [pdf]

Precipitation amount and frequency affect seedling emergence and growth of Reaumuria soongarica in northwestern China

SHAN, Lishan; ZHAO, Wenzhi; LI, Yi; ZHANG, Zhengzhong; XIE, Tingting
分类: 生物学 >> 植物学

Climate change is shifting the amount and frequency of precipitation in many regions, which is expected to affect seedling recruitment across ecosystems. However, the combined effects of precipitation amount and frequency on seedling recruitment remain largely unknown. An understanding of the effects of precipitation amount and frequency and their interaction on seedling emergence and growth of typical desert plants is vital for managing populations of desert plants. We conducted two experiments to study the effects of variation in precipitation on Reaumuria soongarica (Pall.) Maxim. First, greenhouse experiments were conducted to examine the effects of three precipitation amount treatments (ambient, +30%, and −30%) and two precipitation frequency treatments (ambient and −50%) on seedling emergence. Second, the morphological responses of R. soongarica to changes in precipitation amount and frequency were tested in a controlled field experiment. Stage-specific changes in growth were monitored by sampling in different growth seasons. Our results showed that precipitation amount significantly affected germination, seedling emergence, and growth of R. soongarica, and there was a larger effect with decreased precipitation frequency compared with ambient. Germination and seedling emergence increased as precipitation increased under the same frequency of precipitation. The highest emergence percentage was obtained with a 30% increase in precipitation amount and a 50% reduction in precipitation frequency. Compared with ambient precipitation, a 30% increase in precipitation amount increased above- and below-ground biomass accumulation of R. soongarica during the growth season. A decrease of 30% in precipitation amount also resulted in an increase in below-ground biomass and root/shoot ratio in the early stages of the growth season, however, above- and below-ground biomass showed the opposite results at the end of the growth season, with larger effects on above-ground than below-ground biomass under decreased precipitation frequency. When precipitation frequency decreased by 50%, values of all growth traits increased for a given amount of precipitation. We concluded that precipitation frequency may be as important as precipitation amount to seedling emergence and growth of R. soongarica, and that understanding the effects of precipitation variability on seedling recruitment requires the integration of both precipitation amount and frequency. In particular, the combination of a 30% increase in precipitation amount and 50% reduction in precipitation frequency increased the emergence and growth of seedlings, suggesting that alteration of amount and frequency of precipitation caused by climate change may have significant effects on seedling recruitment of R. soongarica.

提交时间: 2018-07-05 来自合作期刊:《Journal of Arid Land》 点击量138下载量31 评论 0

7. chinaXiv:201807.00002 [pdf]

环介导等温扩增技术检测食品安全的研究进展

王静; 许鑫; 王雪雨; 姚伦广; 阚云超; 冀君
分类: 生物学 >> 生物工程

食品安全一直是全世界公众健康的关注焦点。环介导等温扩增(Loop-mediated isothermal amplification,LAMP)技术是一种特异性强、灵敏度高、快速简便的等温核酸扩增技术,近年来在核酸检测领域有着广泛的研究和应用。将LAMP技术应用到食品安全检测领域,可以快速准确的监控一些食品安全问题对人类健康所构成的危害。因此针对LAMP技术在食品安全检测方面的优势进行分析,并结合LAMP技术与新兴诊断技术平台的联合运用进行了展望。

提交时间: 2018-07-01 来自合作期刊:《中国生物工程杂志》 点击量247下载量45 评论 0

8. chinaXiv:201807.00003 [pdf]

铜绿假单胞菌Ⅵ型分泌系统的研究进展

方雪瑶; 胡龙华; 杭亚平; 俞凤; 陈艳慧; 钟桥石
分类: 生物学 >> 生物工程

铜绿假单胞菌是一种能引起多部位急慢性感染且难以用抗生素控制的机会致病菌,近年来已成为院内感染的主要致病菌之一。大量研究表明,细菌将毒力因子精准输送至宿主细胞是其致病的关键,分泌系统在这一过程中扮演重要作用,其中近期发现的Ⅵ型分泌系统(Type VI secretion system,T6SS)在铜绿假单胞菌与宿主间的相互作用和促进生物膜的形成等机制中发挥重要作用,已引起国内外学者高度关注。着重对铜绿假单胞菌T6SS的结构组成、效应功能和调节机制等相关研究进行简要综述,旨在为铜绿假单胞菌感染患者的治疗提供新策略。

提交时间: 2018-07-01 来自合作期刊:《中国生物工程杂志》 点击量187下载量60 评论 0

9. chinaXiv:201806.00247 [pdf]

利用GAP启动子在毕赤酵母中组成型表达人鹅型溶菌酶2

黄 鹏; 闫丽萍; 张宁; 石金磊
分类: 生物学 >> 生物工程

利用甘油醛三磷酸脱氢酶(glyceraldehydes-3-phosphatedehydrogenase,GAP)启动子在毕赤酵母中表达人鹅型溶菌酶2(human goose-type lysozyme 2,hLysG2),并在小试规模建立一套有效的重组hLysG2(recombinant hLysG2,rhLysG2)生产工艺流程。根据毕赤酵母密码子偏爱性设计并人工合成hLysG2基因,将其连接至pGAPZαA 质粒中,构建重组表达质粒pGAPZαA-hLysG2。将重组表达载体线性化后电转化毕赤酵母GS115感受态细胞,通过Zeocin抗性筛选获取高拷贝重组菌株,并在5L生物反应器中进行发酵培养。发酵60 h后发酵液上清酶活性达到最高, 发酵液上清经SDS-PAGE及Western blot检测证实rhLysG2得到表达。与诱导型表达相比,组成型表达发酵时间缩短了48 h,上清中rhLysG2总活性提高了23.8%;使用甲壳素亲和层析和分子筛层析对rhLysG2进行纯化后,每升发酵液上清可纯化到187.4 mg重组蛋白,纯化产物纯度达99.0%以上;浊度测定法分析显示,在pH 5.6、30 ℃和0.1 mol/L Na+的条件下,rhLysG2可达到最大酶活性13500 U/mg。利用GAP启动子在毕赤酵母中成功表达了高纯度和高活性的rhLysG2,避免了甲醇的使用,缩短了发酵时间,提高了蛋白产量,为将rhLysG2开发为新型抗耐药菌药物奠定了基础。

提交时间: 2018-06-27 来自合作期刊:《中国生物工程杂志》 点击量292下载量105 评论 0

10. chinaXiv:201806.00248 [pdf]

‘东红’猕猴桃高效再生体系的建立

吕海燕1; 李大卫; 钟彩虹
分类: 生物学 >> 植物学 >> 植物学研究、实验与植物演化、发展

为有力的推动猕猴桃产业化种苗生产及推广,快速高效的繁育猕猴桃新种质资源,同时为猕猴桃多倍体育种、转基因育种等新兴育种技术创造新种质资源奠定基础,该研究以‘东红’猕猴桃叶片、叶柄为外植体,探讨了不同植物生长调节剂种类及质量浓度组合对不定芽诱导过程中不定芽形成的影响,并研究了不同植物生长调节剂对‘东红’组培苗不定根诱导的影响。结果表明,‘东红’再生最佳外植体为叶柄。叶柄不定芽再生最佳培养基为MS + 0.5 μg·mL-1 6-BA + 0.2 μg·mL-1 NAA,不定芽平均再生率为91.2%,不定芽经过壮苗培养(MS + 0.2 μg·mL-1 6-BA + 0.05 μg·mL-1 NAA),取2~3 cm高幼苗进行生根诱导,不定根再生 率为93%,平均根数为6条。生根后,种苗移栽成活率达80%以上。初步建立了‘东红’叶柄高效再生体系,为猕猴桃快速的产业化种苗生产提供有力保证,也为后期猕猴桃育种研究提供理论依据。

提交时间: 2018-06-25 来自合作期刊:《广西植物》 点击量387下载量105 评论 0

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