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61.
构建感染草莓镶脉病毒(SVBV)森林草莓的酵母cDNA文库,利用酵母双杂交系统,筛选出与SVBV P1蛋白互作的15种寄主因子。生物信息学分析发现,这15种寄主因子参与茉莉酸途径、泛素化、光合作用、抗病抗逆、蛋白修饰、蛋白运输和氧化还原等多种生物过程。另外,这些寄主因子还具有其他分子功能,包括氧化还原酶活性、蛋白二硫化物异构酶活性和金属离子结合活性等。本研究初步探讨了P1与寄主因子的互作机理,为揭示SVBV侵染森林草莓以及SVBV在寄主中扩展的分子机制提供理论依据。 相似文献
62.
CHEN Meng-yue CHEN Wei-dong LIU Yi-min XIANG Si-cheng YIN Hui-ling ZHANG Zhi-feng 《园艺学报》2019,35(1):106-111
AIM: To explore the effect of shikonin on rat primary cortical neurons in oxygen-glucose deprivation (OGD)-induced injury model.METHODS: The neurons were pretreated with shikonin at different concentrations (0.02, 0.2, 2 and 20 μmol/L) followed by treatment with OGD. Lactate dehydrogenase (LDH) release assay and fluorescein diacetate/propidium iodide (FDA/PI) double staining were used to detect neuronal viability and apoptosis, and then the optimal concentration of shikonin was determined. LY294002 (PI3K/Akt signaling pathway inhibitor, 1 μmol/L) was added before the addition of shikonin, and the protein level of p-Akt (Ser473) in the neurons was determined by Wes-tern blot. LDH release assay and FDA/PI double staining were also used to detect neuronal viability and apoptosis.RESULTS: A certain concentration (0.2~20 μmol/L) of shikonin increased the viability of impaired neurons (P<0.05) and the protein level of p-Akt (Ser473) in the neurons (P<0.05). The effect of shikonin on neuronal p-Akt (Ser473) levels and the cell death were blocked by LY294002 (P<0.05).CONCLUSION: A certain concentration of shikonin reduces OGD-induced apoptosis of rat primary cortical neurons by activating PI3K/Akt signaling pathway. 相似文献
63.
《The Journal of Applied Poultry Research》2019,28(2):329-338
64.
《山东省农业管理干部学院学报》2018,(3):40-43
3D打印技术作为20世纪新兴制造技术,具有高柔性化,生产周期短,材料利用率高等优点,目前在多个领域均有广泛应用。本文综述了目前3D打印技术的发展现状,常用金属3D打印技术的工作原理、特点及发展制约因素等。 相似文献
65.
66.
为探讨60Co-γ射线对不同庭院月季品种扦插苗的辐射诱变效应,以粉扇、金凤凰、梅朗口红、紫袍玉带、安吉拉、粉色达芬奇、你的眼睛、香槟和九重香9个庭院月季品种的扦插苗为研究对象,60Co-γ射线为辐照源,设置不同剂量(0、25、45、60、80 Gy)进行辐射处理,测定了死亡率、萌芽率、变异率和主要的形态指标。结果表明,随着辐射剂量增加,月季扦插苗平均死亡率逐渐增加,从33.61%(0 Gy)上升至79.71%(80 Gy);植株生长受到显著抑制,植株变异率呈先升高后降低的趋势,辐射剂量为45 Gy时,植株变异率达到最高,占总体变异率(4.20‰)的64.70%。此外,不同品种月季对60Co-γ射线辐射的敏感性不同,半致死辐射剂量也存在差异,其有效值介于26~55 Gy之间。综合60Co-γ射线对月季扦插苗死亡率、生长势和变异率的影响,推荐庭院月季扦插苗的最适辐射剂量为45 Gy,这为月季辐射育种提供了理论基础。 相似文献
67.
为探究辐射对睡莲的生物学效应,对2个睡莲品种弗吉尼亚(Nymphaea Virginia)和奥毛斯特(N.Almost black)的块茎进行不同剂量的60Co-γ射线辐射处理。结果表明,2个睡莲品种的存活率均随辐射剂量的增加而下降,半致死剂量分别为24.342和27.671 Gy。5~10 Gy 剂量60Co-γ辐射处理使睡莲叶面积和浮叶数显著增加,20~40 Gy剂量60Co-γ辐射处理使叶面积和浮叶数显著减少。2个睡莲品种的开花时间均随辐射剂量的增加而延迟,但整个花期长度无显著变化。10~40 Gy剂量60Co-γ辐射处理显著降低了睡莲花径,但对睡莲开花率无显著影响。辐射处理导致2个睡莲品种的叶片均出现红棕色斑块、锯齿、皱缩、小孔、卷曲、黄化等变异,且红棕色斑块的面积随着辐射剂量的增加而增大。辐射处理使黑红色花品种奥毛斯特出现普遍的褪色现象,而白色花品种弗吉尼亚的花色未发生变异。此外,经60Co-γ射线辐射处理后2个睡莲品种均出现了花型变异的现象。本研究结果为利用辐射诱变技术选育睡莲新品种奠定了基础。 相似文献
68.
69.
Na Li Xingxia Ma Hongwei Xu Yongzhong Feng Guangxin Ren Gaihe Yang Xinhui Han Xiaojiao Wang Chengjie Ren 《Soil Use and Management》2020,36(4):751-765
Biochar has been shown to be potentially beneficial for enhancing yields and soil properties, and diminishing nitrogen (N) losses. However, it remains unclear how biochar regulates soil carbon (C) and N to mitigate N losses induced by straw mixing with N fertilizer in dryland soils. Therefore, we investigated the effects of straw mixing (S1), S1 with biochar (SB) and no straw inputs (S0), and routine urea application rates (N1) and 70% of routine rates (N0.7) on yields and N losses, and identify the relationship between N losses and soil C and N compounds. Results showed that N0.7 and N1 were suitable for the maize and wheat seasons, respectively, contributing to mitigating N losses without reducing crop yields. Moreover, in the maize season, N0.7-SB significantly mitigated the straw-induced NH3-N and N2O-N emissions by 106% and 81%, respectively. In the wheat season, N1-SB reduced the straw-induced NH3-N and N2O-N emissions by 35% and 66%, respectively. In addition, N0.7-SB sharply reduced soil inorganic N (SIN) storage in the maize season. Furthermore, the NH3-N and N2O-N emission rates were negatively correlated with dissolved organic carbon/SIN content (0–20 cm) (DOC/SIN0-20). N losses (N2O-N and NH3-N emissions and SIN storage) were positively correlated with SIN0-20, but negatively correlated with soil organic carbon / SIN0-20 (SOC/ SIN0-20). This study provides further evidence that biochar with an appropriate N application rate decreased SIN0-20 and increased DOC/SIN0-20, thus reducing SIN storage and the straw-induced gaseous N emissions without decreasing crop yields. 相似文献
70.
A method for fractionating sorghum proteins using extraction solvents and techniques designed to obtain polymeric protein structures (especially disulfide linked) was developed. Extraction and separation conditions were optimized in terms of completeness of protein extraction, sample stability, and analytical resolution. After pre-extraction of albumins and globulins, a 3-step sequential procedure involving no reducing agents was applied to ground whole sorghum flour. The three fractions obtained represented proportionally different protein polymer contents and molecular weight distribution as evidenced by comparative size exclusion chromatography. Protein composition also varied among the extracts with differences in kafirin composition and non-kafirin proteins detected in the fractions by RP-HPLC and SDS-PAGE analysis. The ability to quantify and further characterize sorghum polymeric protein complexes will be useful for additional studies linking protein structures with functionality and digestibility and variations for these properties within diverse sorghum germplasm. 相似文献