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951.
Bacterial DNA as immune cell activator 总被引:12,自引:0,他引:12
Pattern recognition receptors of the innate and adaptive immune systems apparently recognize unmethylated CpG motifs of bacterial DNA. Cells of the innate immune system are activated directly by CpG motifs, and the resulting response dictates a Th1 bias to the developing adaptive immune response. Interestingly, antigen receptor occupancy of cells of the adaptive immune system augments their responsiveness to CpG motifs, suggesting that co-stimulatory mechanisms are operative. 相似文献
952.
野生稻光周期反应研究 总被引:5,自引:0,他引:5
对稻属不同种及部分中国普通野生稻的光周期反应进行了比较研究,结果表明供试材料在短日下能量提早抽穗,它们对短日诱导的敏感程度与染色体组有一定关系,AA染色体组的稻种,其光周期反应呈明显的多样性,中国东乡,茶酸,江永,仁化普通野生稻短日性强弱不同,与地理分布有关,即分布纬度较高的类型感光性较弱,另外还对群体内光周期反应差异及苗龄效应也作了研究。 相似文献
953.
土壤大气湿度组合对玉米生长和WUE效应研究 总被引:5,自引:0,他引:5
采用人工气候生长箱盆栽试验,模拟土壤和大气湿度不同组合处理,发现土壤干旱和大气干旱显著抑制玉米生长。大气湿度提高,在一定程度能改善作物的水分状况,降低蒸腾,解除土壤干旱危害,产生生长和生理补偿效应,明显提高水分利用效率。 相似文献
954.
金线蛙入蛰时几项生理常数间的关系研究 总被引:1,自引:0,他引:1
本文经统计学分析处理,表明金钱蛙(Ranaplancyi)入蛰时的体长与体重、胴体重和体重与肝重、脂肪体重、生殖腺重之间均存在非常显著的线性相关关系。 相似文献
955.
吴明 《上海生物医学工程》1998,19(1):55-58
本文描述神经干复合动作电位实验的软件设计及其主要特点,友好的人机界面和简便的波形处理,并给出了实际实验结果,由于软件设计在智能化仪器中的重要作用,所以应加以仔细考虑。 相似文献
956.
957.
958.
It was investigated that active oxygen species (AOS) involved in the plant defense responses induced by fungal elicitor xylanase.
When xylanase from the fungusTrichoderma viridae was treated to tobacco suspension cultured cells as an elicitor, β-glucanase activity was increased markedly. Lignin biosynthesis
was also increased and peaked at 72 h after the treatment with xylanase. The treatment of H2O2 also dramatically increased β-glucanase activity at 24 h, which was much earlier than that of xylanase did. Using lucigenin-and
luminol-dependent chemiluminescence, the effects of xylanase on oxidative burst were examined. Superoxide anion (O2) production was peaked at 40 h and 52 h after xylanase treatment and hydrogen peroxide (H2O2) release was peaked at 44 h and 56 h, suggesting H2O2 burst was followed by O2 generation. The scavengers of AOS, n-propyl gallate (PG) and mannitol, inhibited xylanase-induced β-glucanase activity by
85% and 50%, respectively. The activity of superoxide dismutase (SOD), which catalyzes the dismutation of O2 to H2O2, began to increase from 24 h and reached to maximum at 48 h after xylanase treatment. Pretreatment of N,N,-diethyldithiocarbamate
(DDC), known as a SOD inhibitor, caused the inhibition of H2O2 generation by 80% and reduced the β-glucanase activity by 60%. Treatment of 2,5-norbonadiene (NBD), a specific ethylene-action
inhibitor, did not have any significant effect on xylanase-induced β-glucanase activity. This result suggested that ethylene
did not involve in xylanase-induced response. Our results strongly suggest that the AOS generation is an essential component
in plant defense response, in which cell wall degrading enzyme, glucanase, contributes to remove the necrotic tissue induced
by pathogens. 相似文献
959.
Conserved signal transduction pathways that use phosphorelay from histidine kinases through an intermediate transfer protein (H2) to response regulators have been found in a variety of eukaryotic microorganisms. Several of these pathways are linked to mitogen-activated protein kinase cascades. These networks control different physiological responses including osmoregulation, cAMP levels and cellular morphogenesis. 相似文献
960.
Dead cells do tell tales 总被引:14,自引:0,他引:14
The most recent major advances in the study of programmed cell death (PCD) in plants include the observation that peptide inhibitors of caspases inhibit the hypersensitive response. Nitric oxide has been shown to be required for the induction of disease related PCD. Mutant analysis has led to the cloning of the first genes involved in PCD related disease resistance, LSD1 and MLO. 相似文献