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991.
番茄幼苗对接种晚疫病菌的生理响应 总被引:3,自引:1,他引:2
以番茄晚疫病抗病品系CLN2037E、感病品系5号自交系及其杂种一代F1为材料,人工接种番茄晚疫病菌生理小种T1、T2、T3,研究番茄苗期抵抗晚疫病的生理响应.结果显示:(1)感病品系的膜脂过氧化产物丙二醛(MDA)与过氧化氢(H2O2)的含量增加幅度较大,抗病品系的含量则相对稳定,F1代的变化趋势接近感病品系;(2)抗病品系和感病品系的多酚氧化酶(PPO)、过氧化物酶(POD)和超氧化物歧化酶(SOD)活性变化都呈先升高后下降,抗病品系的酶活性高峰出现早且峰值小于感病品系.研究发现,抗病番茄品系幼苗的多项生理指标在接种晚疫病菌后变化幅度小而稳定,并能在短时间内基本恢复到原来的正常状态,从而表现出较强的抗病性. 相似文献
992.
蜡梅AFLP分子标记技术体系的建立 总被引:6,自引:0,他引:6
利用简易CTAB法、改良的CTAB法和SDS法提取蜡梅[Chimonanthus praecox(L.)Link]成熟叶和嫩叶的基因组,并进行了检测比较。结果显示,改良的CTAB法更适合蜡梅基因组DNA的提取,蜡梅叶片的年龄并不影响蜡梅基因组DNA的提取;同时利用AFLP分子标记技术,采用MseI-EcoR I酶切组合,从168对引物中筛选出10对带型分布均匀、多态性高且分辨能力强的引物,分别为:M23E46、M24E46、M25E46、M23E47、M24E47、M41E47、M41E94、M64E94、M64E66和M24E75,并确定了适用于蜡梅AFLP反应的最佳酶切连接、预扩和选扩体系,从而为今后利用AFLP分子标记技术研究蜡梅的品种分类和野生居群的遗传多样性分析打下坚实的基础。 相似文献
993.
人精子甘露糖受体参与诱导卵母细胞皮质颗粒反应 总被引:1,自引:0,他引:1
目的研究人精子甘露糖受体与卵母细胞皮质颗粒反应的关系。方法以亲和层析法纯化的人精子甘露糖受体(purified mannose receptor,pMR)作用去透明带金黄地鼠卵,继而用罗丹明偶联的兵豆凝集素(Tetramethylrhodam ine Isothiocyanate Labeled Lentil,TRITC-LCA)标记。通过荧光显微镜观察被标记的皮质颗粒及卵母细胞表面甘露糖基的变化情况。结果pMR作用卵母细胞后,卵母细胞内的皮质颗粒减少且细胞表面的甘露糖基数量增加。结论pMR作用于卵母细胞表面后,可触发皮质颗粒反应,并使皮质颗粒部分内容物转移到卵母细胞表面。 相似文献
994.
Advanced societies owe their success to an efficient division of labour that, in some social insects, is based on specialized worker phenotypes. The system of caste determination in such species is therefore critical. Here, we examine in a leaf-cutting ant (Acromyrmex echinatior) how a recently discovered genetic influence on caste determination interacts with the social environment. By removing most of one phenotype (large workers; LW) from test colonies, we increased the stimulus for larvae to develop into this caste, while for control colonies we removed a representative sample of all workers so that the stimulus was unchanged. We established the relative tendencies of genotypes to develop into LW by genotyping workers before and after the manipulation. In the control colonies, genotypes were similarly represented in the large worker caste before and after worker removal. In the test colonies, however, this relationship was significantly weaker, demonstrating that the change in environmental stimuli had altered the caste propensity of at least some genotypes. The results indicate that the genetic influence on worker caste determination acts via genotypes differing in their response thresholds to environmental cues and can be conceptualized as a set of overlapping reaction norms. A plastic genetic influence on division of labour has thus evolved convergently in two distantly related polyandrous taxa, the leaf-cutting ants and the honeybees, suggesting that it may be a common, potentially adaptive, property of complex, genetically diverse societies. 相似文献
995.
Palmer AM Grobbel B Brehm C Zimmermann PJ Buhr W Feth MP Holst HC Simon WA 《Bioorganic & medicinal chemistry》2007,15(24):7647-7660
A series of novel tetrahydroimidazo[2,1-a]isoquinolines was prepared based on a hetero Diels–Alder reaction between an enamine and 1,2,4-triazine as key step. A structure–activity relationship was established focussing on the influence of the substitution pattern in position 3 and 6 of the heterocycle on antisecretory activity, lipophilicity, and pKa value. Potent inhibitors of the gastric acid pump were identified. 相似文献
996.
中药配合物新药是中药新药研制的新思路。本文通过正交实验和单因素实验研究了溶剂、温度、pH值对甘草酸与铬(Ⅲ)离子配位的影响,并利用红外光谱研究反应物的比例对配位反应的影响。结果表明,最佳的配合反应条件是pH 5.0、乙醇浓度10%(v/v)和温度30℃;反应物比例不同,所得配合物的红外光谱基本一致。 相似文献
997.
板蓝根热加工过程中氨基酸组分分析 总被引:4,自引:3,他引:1
利用氨基酸自动分析仪对板蓝根的新鲜植物组织和不同加工程度的板蓝根药材中的总氨基酸和游离氨基酸含量进行测定。结果表明:板蓝根的新鲜植物组织和不同加工程度的板蓝根药材氨基酸在含量上有明显差别。结论为:不同加工程度的板蓝根药材中氨基酸含量差别明显,其中碱性氨基酸含量的差别尤其显著,该差异可能是由于加工过程中发生美拉德反应造成的。 相似文献
998.
Ji Young Hyun Kodiveri Muthukalianan Gothandam Nam Kwon Baek Gongwei Wang Yong-Yoon Chung 《Journal of Plant Biology》2007,50(2):161-166
InBrassica, self-incompatibility (SI) can be overcome by CO2 application, an effective method for obtaining numerous inbred lines for F, commercial seed. We previously reported two different
S-alleles ofBrassica campestris, S733 and S734, with extremely different degrees of susceptibility to this gas. In the current study, we raised a cross-population between
those two genetic lines, and analyzed their reaction level of self-incompatibility to CO2 (RLSICO2). Here, all 40 of our progeny from the F1 cross-population were susceptible, maintaining high values of RLSICO2. This suggests that the susceptible line, S734, is dominant to the insusceptible line, S733. We also generated an F2 selfing-population of each crossed progeny, S733♀ S734♂ and S733♂ S734♀, to assess the RLSICO2 of each individual. PCR-RFLP analysis was performed to determine the S-genotype of the F2 population. The S734 allele segregated in a theoretical ratio of the dominant trait, and the RLSICO2 was consistent with the dominance relationship. Therefore, we have now demonstrated that high RLSICO2 in β.campestris is controlled by a dominant gene.
Both authors contributed equally to this work 相似文献
999.
T. Sretenović-Rajičić S. Ninković B. Uzelać B. Vinterhalter D. Vinterhalter 《Russian Journal of Plant Physiology》2007,54(5):653-658
Two inbred lines of Brassica oleracea L. var. capitata were transformed with two Agrobacterium tumefaciens strains harboring resistance to herbicide Basta: AGL1/pDM805 and LBA4404/pGKB5 (LB5-1). Inoculated cotyledons and hypocotyls
provided equally good explants and manifested a high percentage of shoot regeneration on MS medium supplemented with 1 mg/l
benzyladenine and 0.5 mg/l indole-3-butyric acid. The P34I5 genotype was superior to P22I5 in shoot regeneration (48.1 vs. 26.9%), multiplication, and acclimation in the greenhouse (76 vs. 40%). A. tumefaciens AGL1/pDM805 provided more regenerated shoots per explant, especially in the case of cotyledon explants, and the higher transformation
rate (up to 35% vs. up to 12%) as compared to LB5-1. Putative transformants survived spraying with 10–30 mg/l phosphinothricin.
Transformation was confirmed by GUS assay and PCR analysis in T0 and T1 generations.
Published in Russian in Fiziologiya Rastenii, 2007, vol. 54, No. 5, pp. 738–743.
The text was submitted by the authors in English. 相似文献
1000.
Zhang H Zhou Q Li X Zhao W Wang Y Liu H Li N 《Molecular reproduction and development》2007,74(4):497-501
The regulation of sperm capacitation is important for successful fertilization. Ginsenosides, the biologically effective components of ginseng, have been found to enhance intracellular nitric oxide (NO) production and the latter has recently been indicated to play a significant role in modulation of sperm functions. We investigated the effect of Ginsenoside Re on human sperm capacitation in vitro and the mechanism by which the Ginsenosides play their roles. Spermatozoa were separated by Percoll and incubated with 0, 1, 10, or 100 microM of Ginsenoside Re. The percentages of spontaneous and lysophosphatidylcholine (LPC)-induced acrosome reaction (AR), as a measure of sperm capacitation, were assayed with fluorescein isothiocyanate-conjugated Pisum sativum agglutinin (FITC-PSA). The intracellular cGMP level was measured by [(3)H] cGMP radioimmunoassay system. The results showed that the percentages of both spontaneous and LPC-induced AR and intracellular cGMP level were significantly enhanced by Ginsenoside Re with a concentration-dependent manner. Sodium nitroprusside (SNP, 100 nM), a NO donor, mimicked the effects of Ginsenoside Re. And pretreatment with a NOS inhibitor N(omega)-nitro-l-arginine methyl ester (L-NAME, 100 microM) or a NO scavenger N-acetyl-l-cysteine (LNAC, 1 mM) completely blocked the effects of Ginsenoside Re. Furthermore, the AR-inducing effect of Ginsenoside Re was significantly reduced in the presence of the soluble guanylate cyclase inhibitor LY83583 or cGMP-dependent protein kinase (PCK) inhibitor KT5823, whereas addition of the cGMP analogue 8-Br-cGMP significantly increased the AR of human spermatozoa. Data suggested that Ginsenoside Re is beneficial to sperm capacitation and AR, and that the effect is accomplished through NO/cGMP/PKG pathway. 相似文献