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991.
992.
A mapping population of F(8)derived recombinant inbred lines (RILs) was established from a cross between a domesticated breeding line 83A:476 and a wild type P27255 in narrow-leaf lupin (Lupinus angustifolius L.). The parents together with the 89 RILs were subjected to DNA fingerprinting using microsatellite-anchored fragment length polymorphism (MFLP) to rapidly generate DNA markers to construct a linkage map. Five hundred and twenty two unique markers of which 21% were co-dominant, were generated and mapped. Phenotypic data for the domestication traits: mollis (soft seeds), leucospermus (white flower and seed colour); Lentus (reduced pod-shattering), iucundis (low alkaloid), Ku (early flowering) and moustache pattern on seed coats; were included. Three to 7 molecular markers were identified within 5 cM of each of these domestication genes. The anthracnose resistance gene Lanr1 was also mapped. Linkage groups were constructed using MapManager version QTXb20, resulting in 21 linkage groups consisting of 7 or more markers. The total map length was 1543 cM, with an average distance of 3.4 cM between adjacent markers. This is the first published map for a lupin species. The map can be exploited for marker assisted selection for genetic improvement in lupin breeding programs.  相似文献   
993.
Cytochrome P450 monooxygenases are a major metabolic mechanism responsible for pyrethroid resistance in Helicoverpa armigera (Hübner) from Asia. Cytochrome P450-mediated O-demethylation activity toward p-nitroanisole (PNOD) of individual fourth instars was determined in five strains of H. armigera by using a microplate reader. The four resistant strains of YS, HD, YGF, and YG59 had 6-, 71-, 2540-, and 11,800-fold resistance, respectively, to fenvalerate in comparison with the susceptible BK77 strain. Their mean PNOD activity was 4-, 10-, 24-, and 60-fold, respectively, compared with the BK77 strain. A strong positive correlation (correlation coefficient r = 0.98) between PNOD activity and fenvalerate resistance was found. Of 48 larvae from each strain, only 4% larvae of the susceptible BK77 strain had detectable PNOD activity, whereas 25, 33, 79, and 96% of larvae from the resistant strains YS, HD, YGF, and YG59 exhibited PNOD activity, respectively. There was a clear discrimination of patterns of PNOD frequency distribution between H. armigera strains and their magnitudes of fenvalerate resistance. The PNOD activity can be used as a biochemical marker for monooxygenase-mediated pyrethroid resistance in field populations of H. armigera.  相似文献   
994.
995.
p38MAPK介导的胶质细胞iNOS的转录激活机制   总被引:4,自引:2,他引:4  
丝裂原激活蛋白激酶(MAPK)酶级联反应系统参与胶质细胞中iNOS的合成.通过瞬时转染p38MAPK途径中上游激酶,MAPK激酶3(MKK3)和MAPK激酶6 (MKK6 )表达质粒,进一步了解p38MAPK级联传导信号系统调节iNOS基因在胶质细胞中的转录激活机制.MKK3或MKK6表达质粒与接有荧光素酶(luciferase ,Luc)的大鼠iNOS启动基因质粒(iNOS Luc)联合转染C6星形胶质细胞株引起iNOS Luc的激活,并且使细胞因子诱导的iNOSmRNA的表达增强.这两种效应都能够被p38MAPK抑制剂SB2 0 35 80所抑制.MKK3 6也可以诱导核因子κB(NFκB Luc)依赖的转录活性.这些分子水平的研究结果为p38MAPK信号级联传导途径在调节大鼠胶质细胞中iNOS基因转录激活中的重要作用,包括转录因子NFκB的作用提供了证据.通过阻断iNOS表达或NO的生成,抑制细胞炎症发生,为防治神经细胞炎症反应性疾病提供实验依据.  相似文献   
996.
997.
hbrp(Human BSP-Related Protein)是我们实验室最近在睾丸组织中克隆的一个人与BSP(bovine seminal plasma)蛋白相关的新基因。为了将有关该新基因信息与现有人类基因组转录图相整合,我们应用荧光原位杂交(fluorescent in situ hybridizationFISH)法进行了该基因的人染色体基因定位,结果成功地将hbrp基因定位在人19号染色体长臂1区3带上。hbrp基因是在对BSP蛋白功能的研究过程中发现并克隆的,其同源性分析发现,与其序列最相近  相似文献   
998.
Cassava pulp was hydrolyzed with acids or enzymes. A high glucose concentration (>100 g/L) was obtained from the hydrolysis with 1 N HCl at 121 °C, 15 min or with cellulase and amylases. While a high glucose yield (>0.85 g/g dry pulp) was obtained from the hydrolysis with HCl, enzymatic hydrolysis yielded only 0.4 g glucose/g dry pulp. These hydrolysates were used as the carbon source in fermentation by Rhizopus oryzae NRRL395. R. oryzae could not grow in media containing the hydrolysates treated with 1.5 N H2SO4 or 2 N H3PO4, but no significant growth inhibition was found with the hydrolysates from HCl (1 N) and enzyme treatments. Higher ethanol yield and productivity were observed from fermentation with the hydrolysates when compared with those from fermentation with glucose in which lactic acid was the main product. This was because the extra organic nitrogen in the hydrolysates promoted cell growth and ethanol production.  相似文献   
999.
Permafrost, covering approximately 25% of the land area in the Northern Hemisphere, is one of the key components of terrestrial ecosystem in cold regions. As a product of cold climate, permafrost is extremely sensitive to climate change. Climate warming over past decades has caused degradation in permafrost widely and quickly. Permafrost degradation has the potential to significantly change soil moisture content, alter soil nutrients availability and influence on species composition. In lowland ecosystems the loss of ice-rich permafrost has caused the conversion of terrestrial ecosystem to aquatic ecosystem or wetland. In upland ecosystems permafrost thaw has resulted in replacement of hygrophilous community by xeromorphic community or shrub. Permafrost degradation resulting from climate warming may dramatically change the productivity and carbon dynamics of alpine ecosystems. This paper reviewed the effects of permafrost degradation on ecosystem structure and function. At the same time, we put forward critical questions about the effects of permafrost degradation on ecosystems on Qinghai–Tibetan Plateau, included: (1) carry out research about the effects of permafrost degradation on grassland ecosystem and the response of alpine ecosystem to global change; (2) construct long-term and located field observations and research system, based on which predict ecosystem dynamic in permafrost degradation; (3) pay extensive attention to the dynamic of greenhouse gas in permafrost region on Qinghai–Tibetan Plateau and the feedback of greenhouse gas to climate change; (4) quantitative study on the change of water-heat transport in permafrost degradation and the effects of soil moisture and heat change on vegetation growth.  相似文献   
1000.
One of the biggest challenges for small interfering RNAs (siRNAs) as therapeutic agents is their insufficient cellular delivery efficiency. We developed long circulating and cationic liposomes to improve the cell uptake and inhibitory effectiveness of siRNA on the expression of vascular endothelial growth factor (VEGF) in cancer cells. SiRNA liposomes were obtained by polyelectrolyte complexation between negatively charged siRNA and positively charged liposome prepared by a hydration method. Gel electrophoresis was used to evaluate the loading efficiency of siRNA on the cationic liposome. The optimized siRNA liposomes were observed to be spherical in shape and had smooth surfaces with particle sizes of 167.7?±?2.0?nm and zeta potentials of 4.03?±?0.69?mV, which had no significant change when stored at 4?°C for three months. Fluorescence-activated cell sorting studies and confocal laser scanning images indicated that the cationic liposomes significantly increased the uptake of fluorescence-labeled siRNA in cancer cells. Effects of the siRNA on the inhibition of VEGF were tested by measuring concentrations of VEGF in cell culture media via an enzyme-linked immunosorbent assay and intracellular VEGF levels using a western blotting method. The liposomal siRNA was significantly effective at inhibiting the expression of VEGF in lung, liver and breast cancer cells. Optimal liposomes could effectively deliver siRNA into cancer cells and inhibit VEGF as a therapy agent.  相似文献   
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