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991.
向日葵CMS育性恢复的研究 总被引:4,自引:1,他引:3
向日葵细胞质雄性不育(Cytoplasmicmalesterility,CMS)育性恢复的机理是非常复杂的。运用遗传学和分子生物学方法,分析了具代表性的4种不同细胞质类型的CMS育性被恢复的频率和20种向日葵自交系对19种CMS的恢复能力及个别CMS植株自发恢复的原因。实验结果表明,4种CMS品系育性被恢复的频率分别为58.8%.56.3%.11.8%和0%.20种自交系的恢复力为5.9-75.0%。部分CMS品系和大多数自交系含有恢复基因,恢复基因的数量及类型决定了CMS品系被恢复的程度及自交系的恢复能力。同时,提出并证实了线粒体不育基因变异是导致ARG1CMS植株自发恢复育性的主要原因。 相似文献
992.
Using terminal deoxynucleotide transferase-mediated dUTP-digoxigenin nick end labeling (TUNEL) assay and propidium iodide-DNA
staining flow cytometry assay, the effects of mouse thymic dendritic cells (MTSC4) on the process of programmed cell death
of thymocytesin vitro were investigated. It was noticed that thymocytes bound to MTSC4 used in this study. That the percentages of apoptotic nuclei
of the bound thymocytes on MTSC4 were much higher than those of medium-cultured thymocytes, while the bound thymocytes on
mouse thymic epithelial cell (MTEC1) showed much lower percentages of apoptosis. FACS analysis quantitatively confirmed the
observation. Phenotype analysis showed that MTSC4 induced the deletion of CD4 + CD8 + cells and CD4 + CD8-.cells in 18 h of
coculture. The results suggest that the negative selection of medullary thymocytes may be achieved by thymic dendritic cells
through their enhancing effects on apoptosis.
Project supported by the National Natural Science Foundation of China (Grant No.39670685) and FokYin Tung Education Foundation. 相似文献
993.
Hai-Yun Xiao Aaron Balog Ricardo M. Attar David Fairfax Linda B. Fleming Christian L. Holst Gregory S. Martin Lana M. Rossiter Jing Chen Mary-Ellen Cvjic Janet Dell-John Jieping Geng Marco M. Gottardis Wen-Ching Han Andrew Nation Mary Obermeier Cheryl A. Rizzo Liang Schweizer Thomas Spires Weifang Shan Gregory Vite 《Bioorganic & medicinal chemistry letters》2010,20(15):4491-4495
A novel series of 4-[3,5-dioxo-11-oxa-4,9-diazatricyclo[5.3.1.02,6]undec-4-yl]-2-trifluoromethyl-benzonitriles has been synthesized. The ability of these compounds to act as antagonists of the androgen receptor was investigated and several were found to have potent activity in vitro and in vivo. 相似文献
994.
Qi-he Chen Jing Liu Hai-feng Zhang Guo-qing He Ming-liang Fu 《Enzyme and microbial technology》2009,45(3):175-180
Betulinic acid, a triterpenoid found in many plant species, has attracted attention due to its important physiological and pharmacological properties. In order to obtain betulinic acid, betulin was submitted to transformation with the selected microorganisms. Betulin biotransformation was carried out with the filamentous fungi Armillaria luteo-virens Sacc QH (ALVS), Aspergillus foetidus ZU-G1 (AF) and Aspergillus oryzae (AO) under seven kinds of transformation condition. As a result of transformation of betulin, A. luteo-virens Sacc QH was the best biocatalyst to produce betulinic acid under the designed conditions. Transformation caused by pre-cultured fungal mycelia, a process designated as G2, was favorable condition for betulin biotransformation as the productivity of betulinic acid was evaluated (>20%). M1 and M2 systems, where the betulin substrate was micro-emulsified in mixtures of Tween 80 and organic solvents, were potential substitutes for G2. The possible pathway of betulin transformation is postulated in this work. The use of fungi and transformation mode described in current work are viable procedures for producing betulinic acid, which is of most importance to replace chemical synthesis ways. 相似文献
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Kyle K Biggar Cheng-Wei Wu Shannon N Tessier Jing Zhang Fabien Pifferi Martine Perret Kenneth B Storey 《基因组蛋白质组与生物信息学报(英文版)》2015,13(2):81-90
Very few selected species of primates are known to be capable of entering torpor. This exciting discovery means that the ability to enter a natural state of dormancy is an ancestral trait among primate... 相似文献