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81.
以春兰×寒香梅杂交种(Cymbidium goeringii×Cymbidium ‘Han Xiang Mei’)为材料,MS+琼脂4 g·L-1+蔗糖20 g·L-1+椰汁100 mL·L-1为基础培养基,通过单因素试验,探讨细胞分裂素(TDZ/6-BA)和无机盐浓度(P、K)对其试管花诱导的影响,测定花芽诱导的蛋白质、可溶性总糖含量与超氧化物歧化酶(SOD)活性及激素水平(IAA、ABA)。结果表明,添加0.2 mg·L-1 TDZ和2 mg·L-1 6-BA的花芽诱导率最高,分别为14.33%和14.00%;无机盐浓度3P/3K和3P/5K的培养基花芽诱导率较高,分别达16.67%和11.33%;花芽诱导最佳培养基为MS(3P, 3K)+TDZ 0.2 mg·L-1+椰汁100 mL·L-1+琼脂 4 g·L-1+蔗糖20 g·L-1,花芽诱导率可达34%左右。生理生化指标检测显示,可溶性蛋白、可溶性总糖含量及SOD活性与花芽诱导率呈正相关;稳定的内源激素IAA和ABA含量对花芽诱导有一定的积极作用,含量过高对花芽诱导有抑制作用。 相似文献
82.
《Biotechnic & histochemistry》2013,88(5):267-271
AbstractArgyrophilic nucleolar organizing region (AgNORs) associated proteins are important for cell proliferation and various diseases. We investigated AgNOR protein synthesis in hair root cells of males and females at different ages using two-dimensional image analysis. Experiments were performed on 58 healthy male and 24 healthy female volunteers in three groups according to age and sex. Hair root cells obtained from hair follicles were stained with silver. Total AgNOR number/total nuclear number (TAN/TNN) and total AgNOR area/nuclear area (TAA/NA) for each nucleus were analyzed. The only significant difference was observed in TAA/NA values for males and females from 6 to 12 years old. We suggest that the difference is due to high NOR activity caused by increased growth hormone production in hair root cells. 相似文献
83.
John Eros 《Arts Education Policy Review》2013,114(2):65-80
Teachers' careers are often considered to consist of two parts: pre-service and in-service. In-service refers to the entire time between a teacher's entry and exit from the profession. Recent research suggests teachers' careers actually consistent of several parts, known as phases or stages and, collectively, as the career cycle. This further suggests that as they pass through different stages, teachers' professional development needs may change. This article presents a review of literature on the career cycle, examines the portion known as the “second stage,” and discusses the policy and professional development implications for music teachers. 相似文献
84.
《Biomarkers》2013,18(6-7):422-428
AbstractObjective: To evaluate whether plasma cell-free DNA (cfDNA) was related to clinical outcome in inoperable stage I non-small cell lung cancer (NSCLC) patients undergoing stereotactic body radiotherapy (SBRT).Materials and methods: Plasma cfDNA was assessed at baseline, before the last day and 45 days after the end of SBRT, in 22 NSCLC patients. Twenty-two healthy controls were also evaluated.Results: Plasma cfDNA was higher in patients than in controls. An association with unfavourable disease-free survival was found for continuous baseline cfDNA increments (HR?=?5.9, 95%CI: 1.7–19.8, p?=?0.04).Conclusion: Plasma cfDNA may be a promising prognostic biomarker in high-risk NSCLC patients. 相似文献
85.
86.
Dave Kelly Andre Geldenhuis Alex James E. Penelope Holland Michael J. Plank Robert E. Brockie Philip E. Cowan Grant A. Harper William G. Lee Matt J. Maitland Alan F. Mark James A. Mills Peter R. Wilson Andrea E. Byrom 《Ecology letters》2013,16(1):90-98
Mast‐seeding plants often produce high seed crops the year after a warm spring or summer, but the warm‐temperature model has inconsistent predictive ability. Here, we show for 26 long‐term data sets from five plant families that the temperature difference between the two previous summers (ΔT) better predicts seed crops. This discovery explains how masting species tailor their flowering patterns to sites across altitudinal temperature gradients; predicts that masting will be unaffected by increasing mean temperatures under climate change; improves prediction of impacts on seed consumers; demonstrates that strongly masting species are hypersensitive to climate; explains the rarity of consecutive high‐seed years without invoking resource constraints; and generates hypotheses about physiological mechanisms in plants and insect seed predators. For plants, ΔT has many attributes of an ideal cue. This temperature‐difference model clarifies our understanding of mast seeding under environmental change, and could also be applied to other cues, such as rainfall. 相似文献
87.
Background
Sorghum is a tropical C4 cereal that recently adapted to temperate latitudes and mechanized grain harvest through selection for dwarfism and photoperiod-insensitivity. Quantitative trait loci for these traits have been introgressed from a dwarf temperate donor into hundreds of diverse sorghum landraces to yield the Sorghum Conversion lines. Here, we report the first comprehensive genomic analysis of the molecular changes underlying this adaptation.Results
We apply genotyping-by-sequencing to 1,160 Sorghum Conversion lines and their exotic progenitors, and map donor introgressions in each Sorghum Conversion line. Many Sorghum Conversion lines carry unexpected haplotypes not found in either presumed parent. Genome-wide mapping of introgression frequencies reveals three genomic regions necessary for temperate adaptation across all Sorghum Conversion lines, containing the Dw1, Dw2, and Dw3 loci on chromosomes 9, 6, and 7 respectively. Association mapping of plant height and flowering time in Sorghum Conversion lines detects significant associations in the Dw1 but not the Dw2 or Dw3 regions. Subpopulation-specific introgression mapping suggests that chromosome 6 contains at least four loci required for temperate adaptation in different sorghum genetic backgrounds. The Dw1 region fractionates into separate quantitative trait loci for plant height and flowering time.Conclusions
Generating Sorghum Conversion lines has been accompanied by substantial unintended gene flow. Sorghum adaptation to temperate-zone grain production involves a small number of genomic regions, each containing multiple linked loci for plant height and flowering time. Further characterization of these loci will accelerate the adaptation of sorghum and related grasses to new production systems for food and fuel. 相似文献88.
目的:对比分析支气管动脉灌注化疗与支气管动脉灌注化疗十栓塞术治疗中晚期肺癌的临床疗效。方法:将我院2011年1月-2013年1月期间收治的76例中晚期肺癌患者随机分为两组,即观察组38例,对照组38例。观察组患者行支气管动脉灌注化疗联合栓塞术治疗,对照组患者行单纯支气管动脉灌注化疗治疗。分别对两组患者治疗后的临床治疗效果进行评价,同时观察两组患者治疗后的不良反应及并发症的发生情况。结果:观察组患者临床治疗的总有效率为84.21%,对照组为64.78%.两组比较,差异具有统计学意义(P〈0.05)。两组患者治疗后,观察组患者总不良反应率为23.67%,对照组为21.04%,两组比较.差异无统计学意义(P〉0.05)。且经对症处理后,均得到有效改善。结论:支气管动脉灌注化疗联合栓塞术治疗中晚期肺癌的,临床疗效明显优于单纯支气管动脉灌注化疗,且无明显不良反应及并发症的发生,安全性好,值得临床推广与应用。 相似文献
89.
五月季竹开花及复壮过程中DNA甲基化的MSAP分析 总被引:1,自引:0,他引:1
孙慧敏;顾小平;袁金玲;岳晋军 《植物研究》2013,33(6):723-730
以五月季竹为材料,采用MSAP技术对其开花及花后无性复壮过程中的DNA甲基化状况进行检测,分析其开花前后的甲基化动态,以揭示竹子开花及复壮过程中的表观遗传变化规律。结果显示:(1)五月季竹开花时其叶片甲基化水平降低,而在无性复壮产生不再开花新竹的过程中其叶片甲基化水平又逐渐回升;(2)与未开花竹株相比,五月季竹开花时有29.09%的甲基化位点发生了变异,其中有17.88%的位点在开花植株中发生了完全的去甲基化,远高于发生甲基化位点的比率;(3)复壮竹株与未开花竹株之间发生变异的位点数和所占比率,尤其是发生去甲基化的位点数和比率,低于开花竹株;(4)开花五月季竹花器官的甲基化水平低于叶片,同时有28.58%的位点发生了甲基化状态的改变,且同样以去甲基化为主。 相似文献
90.
Patryk Czortek Anna Delimat Marcin K. Dyderski Antoni Zięba Andrzej M. Jagodziński Bogdan Jaroszewicz 《Nordic Journal of Botany》2020,38(5)
The ability for vegetative growth and development of generative organs often reflects an adaptation to the environment and may be a suitable proxy for understanding population dynamics of rare relict species. An example of such a plant is Carex lachenalii Schkuhr, an arctic-alpine species, in the temperate zone of Europe only occurring in isolated localities of high-elevation mountain ranges. We aimed to assess whether there were relationships between flower production and clonal growth of C. lachenalii, both at the tuft and plot level, and how co-occurring vegetation could modify this relationship. In the study we focused on population-level traits of C. lachenalii, vegetation traits and components of functional diversity. At the tuft level we found that the proportion of flowering ramets of C. lachenalii decreased with increasing diameter of the tuft. At the plot level, in snowbed vegetation C. lachenalii produced more flowering ramets. We suggest this is due to higher environmental stress, expressed by high importance of habitat filtering (low functional dispersion) in shaping species composition of co-occurring vegetation. In granite grasslands and milder environment (expressed by higher functional dispersion), C. lachenalii produced more vegetative ramets, which we suggest is a result of a more competitive environment. While in snowbeds investment in flowering ramets could promote successful persistence of C. lachenalii, survival of subpopulations occurring in the highly competitive conditions of granite grasslands may be uncertain due to potentially weak adaptation to competition with graminoids and dwarf shrubs. 相似文献