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甜玉米、笋玉米的起源与遗传 总被引:16,自引:0,他引:16
甜玉米是由籽粒鲜嫩、糖份含量高的一类胚乳突变体转育而成的。笋玉米是指幼穗柔软、食用纤维丰富的一类多穗(甜)玉米,也有几种基因型,近二十年来发展迅速,和甜玉米一样,也已成为一种玉米产业。1甜玉米、笋玉米的起源、遗传与基因型关于甜玉米的起源时间,可以追溯... 相似文献
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The efficacy of TKIs in treatment of human primary small cell lung cancer xenograft model in vivo
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Objective: To study the treatmaient of non-small cell lung cancer, we established the HU-Prim allograft transplantation tumor model. Methods: The fresh tumor samples were transplanted in the right scapular subcutaneous layer of the severe combined immunodeficient Non-obese diabetic/severe combined immunodeficient(NOD/SCID) mice. The pathological features of the tumors were observed. Nonnecrotic tissue was inoculated subcutaneously into the right axillary. When the tumor in burdened rat grew approximately 100 mm3, according to the tumor size all the animals were divided into the following four groups, eight rats in each group: solvent control group, gefitinib group(100 mg/kg), erlotinib group(50 mg/kg), afatinib group(20 mg/kg). Aniamals were treated with drugs by intragastric(i.g.) administrated, once daily, for consecutively 14 days. Measure the tumor size 2-3 times every week. Results: Hu Prime1-NSCLC mutant sensitive xenograft model research data showed that reversible tyrosine kinase inhibitors gefitinib, erlotinib and irreversible tyrosine kinase inhibitor afatinib could effectively inhibit tumor growth in EGFR positive NSCLC allografts model. The pharmacodynamic activity of irreversible inhibitor was better than that of the reversible inhibitor. Specimens from clinical anthropogenic tumor retain characteristics of the human primary malignancy, histopathology, biological characteristics, and tumor markers, etc., which can more accurately reflect the characteristics of the tumor and the impact of interventions. Conclusion: The model is not only a good antitumor drug experimental platform, but also a new evaluation tool of individualized medication. 相似文献
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Study of the tolerance of Hippochaete ramosissimum to Cu stress 总被引:1,自引:0,他引:1
LIU Dengyi LI Ying CHU Ling WANG Guanglin & WANG Lilong Biodiversity Research Center Anhui Normal University Wuhu China The Provincial Key Laboratory of Conservation Exploitation of Biological Resources in Anhui Wuhu China 《中国科学:生命科学英文版》2005,48(Z1)
We investigated the tolerance of Hippochaete ramosissimum and the changes in physiological metabolism following exposure to copper using pot experiments and analyzing plant physiology and biochemistry. The results showed that Cu tolerance in Hippochaete ramosissimum varied significantly between different populations; the tolerance of plants living in Cu polluted areas for extended periods of time exceeded that of plants living in unpolluted areas. SOD and POD activities in highly Cu tolerant plants increased noticeably following exposure to Cu. This indicates that maintaining and increasing the two kinds of protective enzyme activities are the primary foundations of plant tolerance. However, no change in CAT activity was demonstrated following Cu exposure. In summary, there existed considerable differences in physiological metabolism between different populations of Hippochaete ramosissimum following exposure to Cu. 相似文献
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REN Yuanyuan DAI Xiuyu ZHOU Jian LIU Jingfang PEI Huadong & XIANG Hua . State Key Laboratory of Microbial Resources Center for Molecular Microbiology Institute of Microbiology Chinese Academy of Sciences Beijing China . Graduate School of Chinese Academy of Sciences Beijing China 《中国科学:生命科学英文版》2005,48(3):221-227
Trehalose is a non-reducing disaccharide of glucosewidely distributed in microorganisms, plants and in-sects. It usually functions as a compatible solute in thestabilization of biological structures under several en-vironment stresses[1,2]. Trehalose has proved to be anactive stabilizer of enzymes, proteins, biomasses, pharmaceutical preparations and even organs fortransplantation. Thus much attention has been paid tothe synthesis pathway of trehalose and the develop-ment of novel and economic… 相似文献
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Alien DNA introgression and wheat DNA rearrangements in a stable wheat line derived from the early generation of distant hybridization 总被引:2,自引:0,他引:2
ZHANG Lianquan LIU Dengcai YAN Zehong & ZHENG Youliang Triticeae Research Institute Sichuan Agricultural University Dujiangyan China 《中国科学:生命科学英文版》2005,48(5):424-433
In general, it requires five or more generations to develop a stable line by the traditional breeding method of cultivar hybrids in self-pollinated crops, such as wheat, barley, and rice. No doubt, the breeding period will be shortened and thus the breeding effi-ciency will be improved if the hybrids can stabilize in early generation. The method of haploid breeding, that is, obtaining stable pure lines (DH lines) of cultivar hybrids with the aid of anther culture and then chro-mosome doubling,… 相似文献
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A.J. HARRIS Qiu-Yun Jenny XIANG 《植物分类学报》2009,47(5):349-368
We propose a simple statistical approach for using Dispersal-Vicariance Analysis (DIVA) software to infer biogeographic histories without fully bifurcating trees. In this approach, ancestral ranges are first optimized for a sample of Bayesian trees. The probability P of an ancestral range r at a node is then calculated as P(rY) = ∑t^n=1 F(rY)t Pt where Y is a node, and F(rY) is the frequency of range r among all the optimal solutions resulting from DIVA optimization at node Y, t is one of n topologies optimized, and Pt is the probability of topology t. Node Y is a hypothesized ancestor shared by a specific crown lineage and the sister of that lineage "x", where x may vary due to phylogenetic uncertainty (polytomies and nodes with posterior probability 〈 100%). Using this method, the ancestral distribution at Y can be estimated to provide inference of the geographic origins of the specific crown group of interest. This approach takes into account phylogenetic uncertainty as well as uncertainty from DIVA optimization. It is an extension of the previously described method called Bayes-DIVA, which pairs Bayesian phylogenetic analysis with biogeographic analysis using DIVA. Further, we show that the probability P of an ancestral range at Y calculated using this method does not equate to pp*F(rY) on the Bayesian consensus tree when both variables are 〈 100%, where pp is the posterior probability and F(rY) is the frequency of range r for the node containing the specific crown group. We tested our DIVA-Bayes approach using Aesculus L., which has major lineages unresolved as a polytomy. We inferred the most probable geographic origins of the five traditional sections of Aesculus and ofAesculus californica Nutt. and examined range subdivisions at parental nodes of these lineages. Additionally, we used the DIVA-Bayes data from Aesculus to quantify the effects on biogeographic inference of including two wildcard fossil taxa in phylogenetic analysis. Our analysis resolved the geographic 相似文献