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81.
In May 2018,a new shoot dieback disease was found in several walnut orchards in Rizhao,Shandong Province.The fungal pathogen was obtained on PDA plate from diseased walnut shoots using a tissue isolation method.The purified fungal isolates formed white to grey colonies on PDA plate and three single spore isolates SDWa1-SDWa3 were obtained.Based on morphological characteristics and analysis of rDNA internal transcribed spacer (ITS),calmodulin (CAL),translation elongation factor 1-α (TEF1) and β-tubulin (TUB) sequences,the fungal isolates were identified as Diaporthe nobilis,a new pathogen on walnut.The test of Koch's rule confirmed that D.nobilis was the pathogen of walnut shoot dieback.To determine optimal growing conditions for the pathogen,its biological characteristics test was conducted.The results showed that the optimal growth temperature and pH value were at 25℃ and pH 5-9,respectively.The optimum carbon source was glucose,and favourable nitrogen source was peptone.  相似文献   
82.
Soil bulk density (BD) and effective cation exchange capacity (ECEC) are among the most important soil properties required for crop growth and environmental management. This study aimed to explore the combination of soil and environmental data in developing pedotransfer functions (PTFs) for BD and ECEC. Multiple linear regression (MLR) and random forest model (RFM) were employed in developing PTFs using three different data sets: soil data (PTF‐1), environmental data (PTF‐2) and the combination of soil and environmental data (PTF‐3). In developing the PTFs, three depth increments were also considered: all depth, topsoil (<0.40 m) and subsoil (>0.40 m). Results showed that PTF‐3 (R2; 0.29–0.69) outperformed both PTF‐1 (R2; 0.11–0.18) and PTF‐2 (R2; 0.22–0.59) in BD estimation. However, for ECEC estimation, PTF‐3 (R2; 0.61–0.86) performed comparably as PTF‐1 (R2; 0.58–0.76) with both PTFs out‐performing PTF‐2 (R2; 0.30–0.71). Also, grouping of data into different soil depth increments improves the estimation of BD with PTFs (especially PTF‐2 and PTF‐3) performing better at subsoils than topsoils. Generally, the most important predictors of BD are sand, silt, elevation, rainfall, temperature for estimation at topsoil while EVI, elevation, temperature and clay are the most important BD predictors in the subsoil. Also, clay, sand, pH, rainfall and SOC are the most important predictors of ECEC in the topsoil while pH, sand, clay, temperature and rainfall are the most important predictors of ECEC in the subsoil. Findings are important for overcoming the challenges of building national soil databases for large‐scale modelling in most data‐sparse countries, especially in the sub‐Saharan Africa (SSA).  相似文献   
83.
分析了当前绿色环保的循环冷却水的处理工艺、现状、机理和应用情况,指出了绿色环保型循环冷却水的重要性,以期引起业内的重视并提供参考。  相似文献   
84.
科研水平高低是学院办学水平的标志和工作水平的折射,也是学院内涵提升,教师成长的平台,同时也是突破学院发展难题,实现职教升级的唯一途径.学院对科研工作的支持力度逐年加大,对其投入也不断增加.要真正把科研工作落到实处,发挥它在高职教师本职工作中的作用,才是抓住了科研工作的根本.  相似文献   
85.
惩罚性赔偿乃补偿性民事责任之重要而有益的补充,某种意义上,惩罚性赔偿制度甚至可称为现当代侵权法发展的一个方向。中国在欺诈性消费合同、恶意不签劳动合同、产品责任领域严重侵权、恶意违反执行程序等领域,应坚持在有法律明文规定的情况下适用惩罚性赔偿制度。惩罚性赔偿金额以所造成损失的2倍赔偿为宜,环境侵权领域和知识产权侵权领域在当前尚不宜适用惩罚性赔偿。  相似文献   
86.
AIM: Secretogranin III (SCG3/Sg III) is extensively distributed in endocrine or endocrine-like cells in human body and plays an important role in some biological functions by regulating peptide hormone secretion and neuroendocrine activity.The distribution and functions of SCG3 make itself as not only one of the most useful biological markers in association with neuroendocrine functions, but also a potential indicator of diagnostic and prognostic evaluation in certain diseases.The gene and protein structures, tissue expression, biological functions as well as pathophysiology and clinical significance of SCG3 are reviewed in this article.  相似文献   
87.
对于年金的时间价值的研究,往往假定利率在整个期间内是固定不变的.但事实上,由于受到多种因素的影响,利率通常具有不确定性.因此,本文采用可逆MA(1)模型对随机利息力进行建模,在此基础上,研究了期末付虹式年金和期末付平顶虹式年金的时间价值问题,给出了上述两种形式年金现值的期望和方差的递推公式.通过数值仿真分析了相关参数对期末付虹式年金现值的期望值的影响,其结论对投资者的投资决策提供了参考依据.  相似文献   
88.
AIM:To study the effects of basic fibroblast growth factor (bFGF) on brain edema, nerve function damage and autophagy related proteins in rats with head injury. METHODS:The rat model of craniocerebral injury (CI) was constructed. The rats were divided into control group, CI group, and low-, middle-and high-dose bFGF groups (n=10). The CI model was established in CI group, while the rats in control group were not given epidural impact. The rats in low-dose, middle-dose and high-dose bFGF groups were given bFGF at 2, 4 and 6 μg, respectively, by intraperitoneal injection after 30 min. The neurological function in the rats was evaluated by improved neurological function scoring. The rat brain tissues were taken, and the water content was detected. The levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and IL-1β in the brain tissue were measured by ELISA. The malondialdehyde (MDA) content was analyzed by thiobarbituric acid method. The activity of superoxide dismutase (SOD) was examined by WST-8 assay. The glutathine peroxidase (GSH-Px) activity was detected by colorimetric method. The protein levels of autophagy related proteins LC3-Ⅱ and beclin-1 in the brain tissues were determined by Western blot. RESULTS:The neurological function score was increased significantly of the rats in CI group. The rat model of craniocerebral injury was successfully constructed. Neurological function scores in the rats in low-dose, middle-dose and high-dose bFGF groups were reduced, the water content of the brain tissue was also reduced (P<0.05). The levels of TNF-α, IL-6 and IL-1 β were decreased in the brain tissues (P<0.05), the content of MDA was declined (P<0.05), the activities of SOD and GSH-Px were increased (P<0.05), the protein levels of LC3-Ⅱ and beclin-1 were decreased, compared with the untreated rats in CI group (P<0.05). CONCLUSION:bFGF improves the nerve function of the rats with craniocerebral injury, reduces the water content of the brain tissue, reduces the expression of autophagic protein LC3-Ⅱ and beclin-1.The mechanism is related to the inhibition of inflammatory reaction and oxidative damage.  相似文献   
89.
为研究不同剂量25羟基维生素D3[25(OH)VD3]对断奶前犊牛血液水平、抗氧化能力和免疫功能的影响,选取18 头健康状况良好的新生荷斯坦犊牛,随机分成3 组,每组6 头进行为期56 天的饲养试验。分为对照组[不添加25(OH)VD3]、低剂量组[25(OH)VD3添加量6 000 IU/头·天]和高剂量组[25(OH)VD3添加量12 000 IU/头·天]。结果表明,与对照组相比,随着25(OH)VD3添加剂量增加,血浆生长激素、胰岛素样生长因子-1、过氧化氢酶、超氧化物歧化酶、总抗氧化能力以及免疫球蛋白G(IgG)含量显著增加(P<0.05),而丙二醛含量随剂量增加而存在降低趋势(P=0.079)。与对照组和低剂量组相比,高剂量组血浆免疫球蛋白A(IgA)含量有增加趋势(P=0.059)。综上所述,断奶前犊牛饲喂高剂量25(OH)VD3有利于促进体内生长激素和胰岛素样生长因子-1分泌,可提高犊牛抗氧化能力,增强免疫功能。  相似文献   
90.
研究一种国外野生沉香乙醚提取物的生物活性并分析其化学成分,为国外野生沉香的进一步研究和开发利用 提供一定的基础。采用乙醚浸提法提取沉香,对提取物分别用 MTT 法、Ellman 法、pNPG 法和贝曼漏斗法进行细胞毒、 乙酰胆碱酯酶抑制、α-葡萄糖苷酶抑制和杀全齿复活线虫活性测试,利用 GC-MS 分析提取物化学成分。结果表明,该 提取物对 5 株人体肿瘤细胞、乙酰胆碱酯酶、α-葡萄糖苷酶和全齿复活线虫均表现出一定的生物活性。GC-MS 检测鉴 定了其中的 26 个化合物,相对含量为 57.39%,包括 23 个倍半萜类成分,相对含量为 56.72%,1 个 2-(2-苯乙基)色酮 类成分,相对含量为 0.35%。本次对此种国外野生沉香的生物活性和化学成分研究,发现沉香乙醚提取物具有杀线虫 的活性,为更好地开发沉香的药用价值提供了一定的科学依据。  相似文献   
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