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101.
通过大鼠急性毒性试验、大鼠脊髓损伤运动功能试验和大鼠脊髓含水量试验,对小美牛肝菌生物碱抑制运动神经系统的原理进行研究。大鼠急性毒性试验结果表明,小美牛肝菌生物碱含有一定的毒性,对机体组织的运动神经系统有一定的影响;大鼠脊髓损伤运动功能试验结果表明,小美牛肝菌所含的生物碱物质能够促进大鼠脊髓损伤恢复,降低大鼠脊髓神经损伤;大鼠脊髓含水量试验结果表明,小美牛肝菌生物碱具有消炎抗氧化作用,能够降低过氧化物对神经细胞的损害。 相似文献
102.
橄榄是中国传统的药用植物,其中多酚类物质是橄榄重要的功效成分之一。目前,橄榄多酚类物质研究较为 广泛,常用的提取方法包括温浸法、超声波辅助提取法、微波辅助提取法、超声与微波协同辅助提取法等,分离纯化 后采用液相色谱或液质联用技术鉴定多酚类物质的种类和成分,并对其抗氧化、抗病毒、抗菌消炎、抗癌抑癌、解酒 护肝和提高机体免疫等方面的药理活性进行验证。此外,橄榄多酚类物质合成和代谢分子机理也已经被初步阐释。基 于上述研究报道,本文进一步对橄榄多酚类物质后续研究方向和产业化开发利用前景进行展望。 相似文献
103.
104.
Chang‐Hoon Shin Hien Thi Dieu Bui Samad Rahimnejad Ji‐Hoon Cha Byung‐Woo Yoo Bo‐Kyeun Lee Hyung‐Jin Ahn Soo‐Il Choi Yun‐Jeong Choi Yong‐Ho Park Jeong‐Dae Kim Kyeong‐Jun Lee 《Journal of the World Aquaculture Society》2014,45(3):258-268
This study was conducted to evaluate the effects of dietary supplementation of Barodon, an anionic alkali mineral complex, on growth, feed utilization, humoral innate immunity and disease resistance of olive flounder. A basal experimental diet was used as a control and supplemented with 0.1, 0.2, 0.3, 0.4, or 0.5% Barodon. Triplicate groups of fish (26.4 ± 0.2 g) were fed one of the diets to apparent satiation twice daily for 10 wk. The growth performance was enhanced (P < 0.05) linearly and quadratically in fish fed diets containing Barodon compared with that in fish fed the control. Feed utilization was significantly improved by Barodon supplementation. Serum lysozyme and antiprotease activities were increased quadratically in Barodon fed groups. Also, significantly higher superoxide dismutase activity was found in Barodon‐fed fish. Dietary supplementation of 0.1–0.3% Barodon resulted in significant enhancement of fish disease resistance against Streptococcus iniae. The findings in this study indicate that dietary supplementation of Barodon can enhance growth, feed utilization, innate immunity, and disease resistance of olive flounder and that the optimum level seems to be 0.1% in diets. 相似文献
105.
为明确非洲猪瘟对生猪等畜产品价格产生重要影响,构建包含非洲猪瘟疫情的猪肉等主要肉类产品价格的动态面板数据,运用PVAR模型研究非洲猪瘟疫情对猪肉、白条鸡、牛肉和羊肉四种主要肉类价格波动的动态影响。结果表明,非洲猪瘟疫情对肉类价格的影响并不一致,从冲击方向上看,非洲猪瘟疫情对猪肉价格的冲击主要为正,对白条鸡价格的冲击在考察期内均为正向,对牛羊肉价格的冲击在零值上下波动且并不显著;从冲击大小上看,非洲猪瘟疫情对猪肉的冲击影响最大,白条鸡价格次之、牛羊肉价格最小;从持续时间上看,非洲猪瘟疫情对白条鸡价格的冲击持续时间最长,猪肉价格次之、牛羊肉价格最短。在观察期内,四种主要肉类价格受到非洲猪瘟疫情的影响随着时间的推移不同程度的衰减,价格波动的主要影响取决于市场上供求关系的变化。应进一步强化生猪等养殖业规范化标准化生产,完善非洲猪瘟等动物疫情监测预警体系,加强生猪等畜产品市场供需调控,促进生猪等畜牧业的稳定可持续发展。 相似文献
106.
107.
Qi Wang Quanwei Zhang Ze Gan Haijiang Li Yang Yang Yong Zhang Xingxu Zhao 《Reproduction in domestic animals》2020,55(2):189-199
Bactrian camel is an ancient and precious species of livestock; that is, unique resources exist in the desert and have important economic and scientific value. In recent years, the number of Bactrian camels has declined sharply. Due to its long reproductive cycle and seasonal oestrus, the mechanism of oestrus is unknown. To identify candidate biomarkers of reproduction, we performed a comprehensive proteomic analysis of serum from Bactrian camel in oestrus and non-oestrus, using isobaric tags for relative and absolute quantitation (iTRAQ) coupled with tandem mass spectrometry. We identified 359 proteins, of which 32 were differentially expressed: 11 were up-regulated and 21 were down-regulated in samples from camels in oestrus. We validated the differential expression of a subset of these proteins using qPCR and Western blot. Gene ontology annotation identified that the differentially expressed proteins function in cellular processes, metabolic processes and immune system processes. Notably, five of the differentially expressed proteins, PCGF5, histone H1.2, RBP4, FOLR1 and ANTXR2, are involved in reproductive regulatory processes in other animals. KEGG enrichment analysis demonstrated significant enrichment in several cardiac-related pathways, such as ‘dilated cardiomyopathy’, ‘hypertrophic cardiomyopathy’, ‘cardiac muscle contraction’ and ‘adrenergic signalling in cardiomyopathy’. Our results suggest that candidate biomarker (PCGF5, histone H1.2, RBP4, FOLR1 and ANTXR2) discovery can aid in understanding reproduction in Bactrian camels. We conclude that the profiling of serum proteomes, followed by the measurement of selected proteins using more targeted methods, offers a promising approach for studying mechanisms of oestrus. 相似文献
108.
The priority of management factors for reducing the yield gap of summer maize in the north of Huang-Huai-Hai region,China
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Yue-e LIU Yu-xin LI Tian-fang LÜ Jin-feng XING Tian-jun XU Wan-tao CAI Yong ZHANG Jiu-ran ZHAO Rong-huan WANG 《农业科学学报》2021,20(2):450-459
Understanding yield potential, yield gap and the priority of management factors for reducing the yield gap in current intensive maize production is essential for meeting future food demand with the limited resources. In this study, we conducted field experiments using different planting modes, which were basic productivity(CK), farmer practice(FP), high yield and high efficiency(HH), and super high yield(SH), to estimate the yield gap. Different factorial experiments(fertilizer, planting density, hybrids, and irrigation) were also conducted to evaluate the priority of individual management factors for reducing the yield gap between the different planting modes. We found significant differences between the maize yields of different planting modes. The treatments of CK, FP, HH, and SH achieved 54.26, 58.76, 65.77, and 71.99% of the yield potential, respectively. The yield gaps between three pairs: CK and FP, FP and HH, and HH and SH, were 0.76, 1.23 and 0.85 t ha~(–1), respectively. By further analyzing the priority of management factors for reducing the yield gap between FP and HH, as well as HH and SH, we found that the priorities of the management factors(contribution rates) were plant density(13.29%)fertilizer(11.95%)hybrids(8.19%)irrigation(4%) for FP to HH, and hybrids(8.94%)plant density(4.84%)fertilizer(1.91%) for HH to SH. Therefore, increasing the planting density of FP was the key factor for decreasing the yield gap between FP and HH, while choosing hybrids with density and lodging tolerance was the key factor for decreasing the yield gap between HH and SH. 相似文献
109.
随着知识经济的兴起,人类传统的知识生产模式正悄然发生革命性的变化。一种被称之为"超学科"的知识生产模式开始崭露头角,它强调知识生产要在多学科共同参与的广阔应用语境下进行,要在各利益方充分商榷、谈判、让步、协调、合作的基础上,形成最终共识,从而找到解决问题的途径。和传统的知识生产模式相比,超学科知识生产模式具有应用语境性、超学科性、异质性、反思性和质量控制标准多元性等典型特征,因而可以对农村地区多媒体英语教学具有良好的启示作用。 相似文献
110.
微生物的发酵过程十分复杂,培养基配方的组成以及培养条件的变化都会对菌体的代谢造成很大的影响。为了使抗生素的产量达到最大化,试验运用了Plackett-Burman试验设计、最陡爬坡试验、BoxBehnken试验设计对放线菌(Actinomycetes)G5进行了发酵条件优化。利用Plackett-Burman试验设计对影响放线菌G5发酵的诸多相关因素进行评估并筛选出3个主要因素,即碳源含量、培养温度和培养时间;之后根据3个主要因素的作用大小和方向进行了最陡爬坡试验;最后运用Box-Behnken试验设计确定最优值,得出其最优培养条件为淀粉含量21.66 g/L、培养温度27.70℃、培养时间7.75 d。在此条件下,抗生素对苹果轮纹病菌的抑菌圈直径为23.00 mm,与模型预测值基本一致。 相似文献