100 research outputs found

    Study on the Effection to Cell Volume and Chlorophyll Content of Leaves of Mangrove Caused by Salinity

    Get PDF
    本文采用快速离析法,应用流式细胞技术分别研究了秋茄(Kandeliacandel)和桐花树(Aegicerascorniculatum)的成熟叶片的叶肉及叶柄薄壁细胞细胞体积和叶绿素含量随盐度变化和它们发育过程的变化而变化的趋势。通过对不同叶龄的秋茄叶肉细胞的研究,得出如下结果:生长于低盐度(18)以下的不同叶龄的叶肉细胞体积波动明显,而在盐度为20及以上的的条件下生长的叶肉细胞则表现为变化幅度小,同一盐度下不同叶龄中叶肉细胞的相对体积相近,这可能是因为在高盐度协迫下,植物生长缓慢的关系。叶龄相同的叶片叶绿素含量在盐度为18和20时出现最大值;芽细胞单位体积叶绿素含量在盐度18时出现最大,从所...This article studyed the mesophyll cell size and chlorophyll content in the leaves of Kandelia candel and Aegiceras corniculatum which were planted under different substrate salinity by using flow cytometry(FCM) and fast isolation method. First, we study on the mesophyll cell size and chlorophyll content of the leaves of Kandelia candel with different leaf age, the result show that: when substrat...学位:理学硕士院系专业:生命科学学院生物学系_植物学学号:20022600

    广告传播中议程设置理论的应用

    Get PDF
    在信息时代,注意力成了稀缺资源。怎样吸引消费者的注意力,怎样让自己的广告资金投入越来越有效益,是每个广告主都必须面对的课题。而作为大众传播效果理论之一的议程设置理论认为,议程设置具有引导受众注意力的功能。本文分析了议程设置理论如何在广告中发挥作用以及应注意的问题

    Effects of the Xitongxiao prescription on apoptosis and proliferation of chondrocytes in knee

    Get PDF
    目的:探讨膝痛消方对促进软骨细胞增殖和抑制IL-1β诱导的软骨细胞凋亡的作用。方法:体外培养膝关节软骨细胞,用阿利新蓝染色方法检测软骨细胞蛋白多糖,用Ⅱ型胶原免疫荧光染色检测软骨细胞Ⅱ型胶原的表达,以鉴定软骨细胞;用MTS检测软骨细胞的增殖;用IL-1β诱导软骨细胞凋亡,AnnexinV/PI双染检测细胞凋亡。结果:膝关节剥离得到的细胞形态为多角形或梭形,阿利新蓝与Ⅱ型胶原免疫荧光染色均呈阳性,证明分离培养的细胞为软骨细胞。MTS实验结果发现膝痛消方提取物处理软骨细胞后检测到的OD值随浓度增加而增加且显著高于对照组。此外,IL-1β处理诱导软骨细胞凋亡,而膝痛消方提取物能够有效地抑制IL-1β引起的细胞凋亡。结论:膝痛消方能促进软骨细胞的增殖,抑制IL-1β诱导的软骨细胞的凋亡。以上发现为膝痛消方临床上治疗膝关节骨性关节炎提供药理作用依据。Objective:To investigate the effects of the Xitongxiao prescription on the cell proliferation and the inhibition of IL-1β-induced apoptosis of chondrocytes.Methods:To identify chondrocytes,the articular chondrocytes were cultured in vitro;staining with alcian blue was used to detect the protein polysaccharide,and staining with collagen immunofluorescence was used to examine the expression of type II collagen in chondrocytes.The proliferation of chondrocytes was determined by MTS.Apoptosis of chondrocytes was induced by IL-1β,and the effect of apoptosis was tested by Annexin V/PI double staining.Results:The morphology of the cells obtained from the knee joint was polygonal or fusiform.The tested results of Alcian blue and collagen immunofluorescence staining were positive.These together certified that the isolated cells were knee chondrocytes.MTS assay results showed that the detected OD values were dosedependently increased and they were significantly higher than those of the control group.In addition,the apoptosis of chondrocytes was induced by IL-1βtreatment.While the extract of the Xitongxiao prescription could effectively inhibit the IL-1β-induced apoptosis of chondrocytes.Conclusion:The Xitongxiao prescription could promote the proliferation of chondrocytes and inhibit the apoptosis of chondrocytes induced by IL-1β.The above findings may provide one of pharmacological mechanisms of the Xitongxiao for clinical treatment of knee osteoarthritis.厦门市科技计划项目(3502z20144031);福建省自然科学基金计划资助项目(2015J01065)

    Advance in Red-emitting Mn⁴⁺-activated Oxyfluoride Phosphors

    Get PDF
    稳定可靠的高光子能量发光(620~650 nm)红光荧光粉, 对于构建低色温、高显指荧光粉转换型白光发光二极管(WLED)至关重要。Mn⁴⁺激活红光荧光粉是当前 WLED 用荧光粉研究热点之一。本文介绍了 Mn⁴⁺离子的能级跃迁与光致发光特性, 详细叙述了目前所报道的七种 Mn⁴⁺激活含 d⁰/d¹⁰/s⁰离子氧氟化物系列红色荧光粉(如Na₂WO₂F₄:Mn⁴⁺等)的制备方法、晶体结构及其发光特性。目前⁴⁺在氧氟化物结构中得到强 R 线(零声子线)发光的情况少, 微观配位体仍是[MnF₆]或[MnO₆], 其化学稳定性和量子效率研究也很缺乏。最后对 Mn⁴⁺激活氧氟化物红光荧光粉的研究进行了展望。The stable and reliable red phosphor with high-photon energy emission (620–650 nm) is critical for the fabrication of the phosphor-converted white light-emitting diode (WLED) with low correlated color temperature and high color rendering index. Mn⁴⁺-activated phosphor is an emerging kind of red-emitting phosphor for WLED. Herein, the energy levels transition and photoluminescence characteristics of the Mn⁴⁺ ion were introduced; then, the preparation, crystal structure and luminescent properties of as-far reported seven kinds of Mn⁴⁺-doped oxyfluoride red phosphors (such as Na₂WO₂F₄:Mn⁴⁺) containing d⁰/d¹⁰ or s⁰ cations were reviewed. Currently, only in quite rare case of oxyfluoride, Mn⁴⁺ was found to exhibit strong R-line emission, with local coordination remaining as either [MnF₆] or [MnO₆]. The studies on the chemical stability and quantum efficiency of Mn⁴⁺ -doped oxyfluoride phosphors are still insufficient. Finally, we prospected the future development of Mn⁴⁺-doped oxyfluoride phosphor

    用流式细胞仪研究秋茄叶柄薄壁细胞大小及叶绿素含量与海水盐度的关系

    Get PDF
    采用快速离析方法和流式细胞仪研究了红树植物秋茄成熟叶柄薄壁细胞的大小和叶绿素含量与海水盐度之间的关系。结果表明 ,海水盐度为 0 .8%~ 2 .0 %时 ,随着盐度的升高 ,叶柄薄壁细胞大小和单位体积叶绿素含量的变化趋势与叶肉细胞一致。海水盐度为 0 .8%~ 1.0 %时 ,随着盐度升高 ,向有利于提高光合作用强度的方向发展 ;海水盐度在 1.0 %~ 2 .0 %之间时 ,随着盐度的升高 ,向加强生理干旱适应性方向发展。海水盐度高于2 .0 %时 ,叶柄薄壁细胞的大小和单位体积薄壁组织叶绿素含量随盐度的变化趋势与叶肉细胞不同 ,原因尚待进一步研究。实验结果表明 ,借助快速离析方法 ,使用流式细胞仪研究器官细胞相关特性是可行的 ,为从形态学角度研究红树植物耐盐机理提供了可能 ,扩大了流式细胞仪的应用领

    连续陶瓷纤维的制备、结构、性能和应用:研究现状及发展方向

    Get PDF
    连续陶瓷纤维是纤维增强陶瓷基复合材料的增强体,对提高陶瓷基复合材料的强度和韧性起关键作用,高损伤容限和高强度陶瓷纤维是阻止裂纹扩展实现陶瓷基复合材料强韧化的保障。本文对碳化硅、氮化硅、氮化硼、氧化铝和氧化锆等几种陶瓷纤维的制备方法、结构、性能和应用等方面进行了全面的综述,指出了今后的发展方向,期望为未来陶瓷纤维的研究、开发及应用提供参考。国家高技术研究发展计划(863)(2003AA305630);;国家自然科学基金(51472144);;山东省科技重大专项(2015ZDZX11003);;山东省青年学者未来计划(2016WLJH27

    东方肉穗草黄酮类化学成分研究

    Get PDF
    目的:系统研究东方肉穗草中的黄酮类化学成分。方法:利用大孔吸附树脂、Sephadex LH-20,ODS及正相硅胶柱等色谱手段进行分离,通过多种波谱学数据分析进行黄酮类化合物的结构鉴定。结果:从醋酸乙酯部分分离得到8个黄酮类化合物,经鉴定为异鼠李素(1)、槲皮素(2)、异鼠李素-3-O-β-D-吡喃葡萄糖苷(3)、槲皮素-3-O-β-D-葡萄糖苷(4)、异鼠李素-3-D-(6″-乙酰基)-β-D-吡喃葡萄糖苷(5)、异鼠李素-3-O-(2″-乙酰基)-β-D-吡喃葡萄糖苷(6)、槲皮素-3-O- (6″-乙酰基)-β-D-吡喃葡萄糖苷(7)、槲皮素-3-O-(6″-反式-对香豆酰基)-β-D-吡喃葡萄糖苷(8)。结论:所有化合物均系首次从该属植物中分离鉴定

    ZnSe/MoO3/TiO2复合膜的制备及其光生阴极保护效应

    Get PDF
    针对TiO2半导体不能有效吸收可见光,光电转换效率较低等问题,可通过对TiO2半导体进行修饰和改性,制备TiO2复合材料,提高其光电化学性能。因此,本工作以Ti表面制备的TiO2纳米管膜为基础,分别应用循环伏安电沉积法和脉冲电沉积法在膜表面先后沉积MoO3和ZnSe颗粒,获得具有级联能带结构的ZnSe/MoO3/TiO2纳米管复合膜,并将其应用于对403不锈钢(403SS)实施光生阴极保护。相较于纯TiO2纳米管膜,紫外-可见(UV-Vis)吸收光谱和光致发光(PL)谱测试表明,ZnSe/MoO3/TiO2复合膜的吸收边红移,在可见光区具有良好的光吸收性能,光生载流子复合得到更有效抑制。光电化学测试表明,白光照射下,处于0.5 mol·L-1 KOH溶液中的ZnSe/MoO3/TiO2复合膜的光电流密度达到了同条件下纯TiO2膜的2倍,可使与之耦连的浸泡于0.5 mol·L-1 NaCl溶液中的403SS电极电位下降470 mV,显示出良好的光生阴极保护效应。复合膜还具有一定的储能特性,在光照后又转为暗态的22.5 h内仍对403SS具有一定阴极保护作用。国家自然科学基金(21573182,51731008,51671163,21621091,J1310024)资助项目~

    Antioxidant enzymes from the crab Scylla paramamosain: Gene cloning and gene/protein expression profiles against LPS challenge

    Get PDF
    Recent studies revealed that antioxidant enzymes play important roles in antioxidant responses caused by metabolic process or pathogen invasion. Catalase is one of these key enzymes which has been characterized and highly conserved from invertebrates to vertebrates. In the present study, a full-length cDNA sequence of catalase was cloned from the hemocyte suppression subtractive hybridization library of the crab Scylla paramamosain. The Sp-catalase (Sp-CAT) cDNA sequence contained 2551 bp with an open reading frame of 1551 bp encoding 517 amino acid residues. The conserved catalytic active residues His-71, Asn-144 and Tyr-354 were predicted in the amino acid sequence of Sp-CAT. The deduced Sp-CAT protein had a calculated molecular mass of 59 kDa with an estimated isoelectric point of 6.4. Multiple alignment analysis revealed that the deduced amino acid sequence of Sp-CAT shared high identity (75.4%) with those of other species. The Sp-CAT mRNA transcripts were demonstrated in multiple tissues of normal S. paramamosain. After LPS challenge, the expression level of Sp-CAT gene was increased significantly in hemocyte at 3 and 6 h, and in hepatopancreas at 6 h, respectively, determined by quantitative real-time PCR. Furthermore, the activities of CAT and SOD were also measured in different tissues and serum after LPS challenge. The CAT activity was significantly increased at 3, 6, 24 and 48 h in hemocyte lysate, at 3 h in serum, and at 24 and 48 h in hepatopancreas after LPS challenge. In addition, the SOD activity was significantly induced at 3 and 6 h in hemocyte lysate, 3 and 12 h in serum, 12 and 48 h in hepatopancreas post LPS stimulation, indicating a tissue and time-dependent antioxidant response in the crab. Taken together, these data demonstrated that a strong antioxidant response occurred in the LPS-challenged crab, which might be involved in the protection of host against microbial infections. (C) 2010 Elsevier Ltd. All rights reserved.National Natural Science Foundation of China (NSFC) [40676083]; National High Technology Research and Development Program of China [2007AA091406]; Minjiang Scholars Program [2009]; Natural Science Foundation of Fujian Province China (NSFC-FPC) [2009J05084

    低龄DDH患儿初次开放复位术中股骨截骨必要性的前瞻性随机对照试验研究方案

    Get PDF
    回顾性研究发现,股骨截骨术并非低龄DDH患儿手术治疗所必须的,而应根据患儿具体情况合理选择;本研究通过多中心前瞻性研究进一步探讨对于18个月至3岁DDH患儿是否要行股骨截骨术。FSODDH项目为一项多中心前瞻性随机对照临床试验研究。研究设计拟招募200名单侧低龄DDH患儿,随机分成股骨截骨组(n=100)和股骨不截骨组(n=100)。股骨截骨组患儿全部采取髋关节开放复位术、骨盆截骨术及股骨截骨术治疗;股骨不截骨组患儿全部采取髋关节开放复位术及骨盆截骨术治疗;术后定期随访至少2年。收集术前、术后1周、术后1个月、术后3个月、术后6个月、术后1年及术后2年的髋关节正位X线影像资料,比较两组患儿的髋臼指数、股骨头坏死率、再脱位率、术中出血量、手术时间和住院天数等临床指标。这一多中心前瞻性研究将能为低龄DDH患儿是否需行股骨截骨术提供循证医学证据
    corecore