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991.
大豆启动功能片段的克隆及在转化甘草中启动β-葡糖苷酸酶基因的表达 总被引:1,自引:0,他引:1
将大豆DNA的HindⅢ和BamHⅠ酶切片段连接到pBⅠ101载体缺启动子的GUS基因上游,构建了含有不同DNA片段的重组质粒,转化大肠杆菌C600,获得了具Km抗性的转化子。通过三亲交配将上述重组质粒转移至发根农杆菌R1000(PRiA4b)中,用注射法,将各含重组质粒的发根农杆菌菌液感染甘草外植体,在含cb的无激素MS培养基上诱发毛状根并再生成植株。转化甘草具Km抗性,有甘露碱和农杆碱存在。经组织化学法检测,在转化株C2和C13的毛根、茎、叶中有靛蓝色沉淀物产生。证明大豆启动功能片段在转化甘草中启动了GUS基因表达。重组质粒的酶切分析证明C2和C13大豆DNA插入片段均约为0.8kb。DNA分子杂交也证明C2、C13 DNA与大豆DNA和转化株DNA有同源性。 相似文献
992.
碳源种类及碳氮比对眼点拟微绿球藻生长密度、油脂含量和脂肪酸组成的影响 总被引:3,自引:0,他引:3
研究了三种碳源Na2CO3、NaHCO3、葡萄糖对眼点拟微绿球藻生长密度和油旨含量的影响,实验结果表明相对于葡萄糖,无机碳源NaHCO3更利于眼点拟微绿球藻的生长.以NaHCO3为碳源,研究了在不同的接种密度、NaNO3浓度下,C/N对眼点拟微绿球藻生长密度和油脂含量的影响.实验结果表明,C/N对眼点拟微绿球藻生长密度的影响与接种密度和NaNO3浓度有关,在高的NaNO3浓度时,C/N对眼点拟微绿球藻生长密度的影响很小;在低的NaNO3浓度时,随着C/N比的增加,微绿球藻的生长密度先增加后下降,存在最佳的C/N比.最佳的C/N比随接种密度而变化,在接种密度为OD440=0.10时,最佳C/N比为3,当接种密度提高到OD440=0.70时,最佳C/N比增加到5.NaNO3浓度和C/N对微藻油脂含量均有较大影响,在不同的接种密度和NaNO3浓度下都表现为C/N=1时最利于微藻油脂的积累,这与卡尔文循环过程中核酮糖-1,5-二磷酸羧化酶/加氧酶的活性有关.本实验的最佳产油培养条件为以NaHCO3为碳源,初始接种密度为OD440=0.70,C/N=1∶1,CNaNO3=0.225g/L,此时油脂产率为56.7 mg/(L·d),EPA产率为6.5 mg/(L·d). 相似文献
993.
994.
以香果树(Emmenopterys henryi)未成熟种子为试材, 探讨不同的接种量、基本培养基、糖浓度及植物生长调节物质等对体细胞胚胎生长的影响, 建立稳定的香果树胚性细胞悬浮培养与植株再生体系。结果表明: 悬浮培养条件下, 最适接种量为2%(鲜重); 较适合的基本培养基为MS; 蔗糖浓度为1%时容易使球形胚聚合体愈伤化, 浓度为3%和6%适合球形胚聚合体增殖, 浓度为9%则容易使球形胚聚合体褐化; 添加0.5 mg.L-16-BA 和0.5 mg.L-1 NAA的MS液体培养基, 当初始蔗糖浓度为3%, 然后逐步提高到6%则有利于香果树各个发育阶段的同步化; 子叶胚转到不含任何植物生长调节物质的MS固体培养基中可以长成正常植株。 相似文献
995.
概述了好好芭的生物学特性,好好芭特色高经济价值产品——好好芭油的合成机制,并跟踪介绍了好好芭分子生物学方面的研究进展,如好好芭油脂合成特异基因的转基因研究和盐调控基因的克隆等。 相似文献
996.
Carrier Interfacial Engineering by Bismuth Modification for Efficient and Thermoresistant Perovskite Solar Cells 下载免费PDF全文
Cong Chen Dali Liu Boxue Zhang Wenbo Bi Hao Li Junjie Jin Xu Chen Lin Xu Hongwei Song Qilin Dai 《Liver Transplantation》2018,8(20)
Organic–inorganic halide perovskite solar cells (PSCs) have emerged as attractive alternatives to conventional solar cells. It is still a challenge to obtain PSCs with good thermal stability and high permanence, especially at extreme outdoor temperatures. This work systematically studies the effects of Bi3+ modification on structural, electrical, and optical properties of perovskite films (FA0.83MA0.17Pb(I0.83Br0.17)3) and the performance of corresponding PSCs. The results indicate that Bi3+ modified PSCs can achieve better thermal stability, photovoltaic response, and reproducibility compared with control cells due to the decreased grain boundaries, enhanced crystallization, and improved electron extraction from perovskite film. As a result, the modified PSC exhibits an optimized power conversion efficiency (PCE) of 19.4% compared with 18.3% for the optimized control device, accompanied by better thermoresistant ability under 100–180 °C and enhanced long‐term stability. The degradation rate of the modified device is reduced by an order of magnitude due to effective structural defect modification in perovskite photoactive layer. It could maintain more than two months at 60 °C. These results shed light on the origin of crystallization and thermal stability of perovskite films, and provide an approach to solve thermal stability issue of PSCs. 相似文献
997.
为建立高效的农杆菌介导的紫花苜蓿的遗传转化体系,以紫花苜蓿无菌苗叶片作为外植体,用8种含有不同激素浓度梯度的培养基对其进行愈伤组织及不定芽的诱导,结果表明,M7培养基(MS+1 mg/L 2,4-D+2 mg/L CH+0.25 mg/L KT+2mg/L琼脂)的愈伤组织诱导率最高,可达100%;继代表现最好,为胚性愈伤组织;同时,继续培养后可直接分化出不定芽,分化率达100%。结果表明,最适宜条件分别为卡那霉素(Kan)筛选浓度为75 mg/L;农杆菌菌液OD600值为0.45-0.6之间。 相似文献
998.
999.
NF-kappa B-inducing kinase establishes self-tolerance in a thymic stroma-dependent manner 总被引:7,自引:0,他引:7
Kajiura F Sun S Nomura T Izumi K Ueno T Bando Y Kuroda N Han H Li Y Matsushima A Takahama Y Sakaguchi S Mitani T Matsumoto M 《Journal of immunology (Baltimore, Md. : 1950)》2004,172(4):2067-2075
Physical contact between thymocytes and the thymic stroma is essential for T cell maturation and shapes the T cell repertoire in the periphery. Stromal elements that control these processes still remain elusive. We used a mouse strain with mutant NF-kappaB-inducing kinase (NIK) to examine the mechanisms underlying the breakdown of self-tolerance. This NIK-mutant strain manifests autoimmunity and disorganized thymic structure with abnormal expression of Rel proteins in the stroma. Production of immunoregulatory T cells that control autoreactive T cells was impaired in NIK-mutant mice. The autoimmune disease seen in NIK-mutant mice was reproduced in athymic nude mice by grafting embryonic thymus from NIK-mutant mice, and this was rescued by supply of exogenous immunoregulatory T cells. Impaired production of immunoregulatory T cells by thymic stroma without normal NIK was associated with altered expression of peripheral tissue-restricted Ags, suggesting an essential role of NIK in the thymic microenvironment in the establishment of central tolerance. 相似文献
1000.
Xie H Rhodus NL Griffin RJ Carlis JV Griffin TJ 《Molecular & cellular proteomics : MCP》2005,4(11):1826-1830
Human saliva has great potential for clinical disease diagnostics. Constructing a comprehensive catalogue of saliva proteins using proteomic approaches is a necessary first step to identifying potential protein biomarkers of disease. However, because of the challenge presented in cataloguing saliva proteins with widely varying abundance, new proteomic approaches are needed. To this end, we used a newly developed approach coupling peptide separation using free flow electrophoresis with linear ion trap tandem mass spectrometry to identify proteins in whole human saliva. We identified 437 proteins with high confidence (false positive rate below 1%), producing the largest catalogue of proteins from a single saliva sample to date and providing new information on the composition and potential diagnostic utility of this fluid. The statistically validated, transparently presented, and annotated dataset provides a model for presenting large scale proteomic data of this type, which should facilitate better dissemination and easier comparisons of proteomic datasets from future studies in saliva. 相似文献