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为进一步研究和开发新植物源农药,拓宽龙须藤(Bauhinia championii)的生物活性研究,探索其不同组分潜在的杀菌和除草活性,该研究通过常温冷浸提取法提取、真空浓缩得到甲醇提取物。结果表明:用硅胶柱层析分离纯化,经TLC检识和碘缸显色后整合得到9个组分。反复重结晶7号和8号组分中析出的物质,经TLC检识和测熔点,得到1个纯化合物,编为33号,经波谱数据分析与molbase库对照,鉴定该化合物为(1R,2S,3S,4S,5S,6S)-6-甲氧基-1,2,3,4,5-环己烷五醇,是一种重要的工业原料。杀菌和除草活性试验结果显示,粗提物在1 000μg·m L~(-1)时对水稻稻瘟病菌的抑制率为(40.84±1.00)%,对稗草根的抑制率为(49.18±2.33)%;各组分在500μg·m L~(-1)时,4号组分对水稻稻瘟病菌的抑制率达到(44.19±0.76)%,2号和3号组分对稗草根的抑制率分别为(88.92±1.31)%和(90.99±1.45)%,3号和6号组分对马齿苋根的抑制率分别为(72.06±1.31)%和(89.92±1.73)%。这表明龙须藤叶提取物对水稻稻瘟病菌、稗草根和马齿苋根有良好的抑制效果,可进一步分离2号、3号、4号、6号组分,以获得高活性的单体化合物。 相似文献
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生态认知视角下的校园雨水花园设计旨在探讨生态语境下校园景观的教育作用。环境教育中的无意识教育方式是通过环境的感染力潜移默化影响受育者,无意识教育方式为受育者提供的开放性、自主性和互动性的教育途径更能深刻影响受育者的认知。基于生态认知的校园雨水花园设计以无意识环境教育思想为指导,运用生态显露设计,以可视化雨水路径刻画雨水生态特征,以满足花园功能、技术和艺术要求且实现可视化雨水路径的空间设计与艺术品质,创造雨水花园的张力场效应和感染力,如空间秩序、材质对比、色彩运用以及空间的愉悦体验等,以促进生态的无意识教育 相似文献
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Lingyu Li Wei Li Chang Wang Xu Yan Yizhuo Wang Chao Niu Xiaoying Zhang Min Li Huimin Tian Cheng Yao Haofan Jin Fujun Han Dongsheng Xu Wei Han Dan Li Jiuwei Cui 《Cytotherapy》2018,20(1):134-148
Background
Despite the availability of multiple treatment strategies, patients with advanced colon carcinoma (CC) have poor prognoses. The aim of this study was to evaluate the efficacy and safety of natural killer (NK) cell therapy in combination with chemotherapy in patients with locally advanced CC.Methods
We assessed the cytotoxicity of NK cells to CC cells (CCs) and CC stem cells (CSCs) pre-treated with 5-fluorouracil or oxaliplatin in vitro. Then, an open-label cohort study was conducted with locally advanced CC patients who had received radical resection. Patients received either NK cell therapy combined with chemotherapy (NK cell group, 27 patients) or pure chemotherapy (control group, 33 patients). Progression-free survival (PFS), overall survival (OS) and adverse effects were investigated.Results
Chemotherapy sensitized CCs and CSCs to NK cell cytotoxicity through regulation of NK cell–activating/inhibitory receptor ligands. Poorly differentiated CCs were more susceptible to NK cells than well-differentiated ones. In the cohort study, the 5-year PFS and OS rates in the NK cell group were significantly higher than those in the control group (51.1% versus 35%, P?=?0.044; 72.5% versus 51.6%, P?=?0.037, respectively). Among patients with poorly differentiated carcinomas and low expression of human leukocyte antigen (HLA)-1, the median PFS in the NK cell group versus the control group was 23.5 versus 12.1 months (P?=?0.0475) and 33.1 versus 18.5 months (P?=?0.045), respectively. No significant adverse reactions were reported.Conclusion
NK cell therapy in combination with chemotherapy in locally advanced CC prevented recurrence and prolonged survival with acceptable adverse effects, especially for poorly differentiated carcinomas. 相似文献129.
研究和探讨海南黎药海巴戟多糖含量,并对多糖含量测量过程中引入的不确定因素进行评估。采用苯酚-硫酸法测定海巴戟药材中多糖含量,并根据苯酚-硫酸法建立数学模型,找出影响不确定的因素,最终确定测量结果的合成不确定度和扩展不确定度。以D-葡萄糖作为对照品,浓度在0.002 5~0.012 5 g/L范围内线性关系良好(R~2=0.999 4),重现性试验RSD=1.84%,4 h内显色稳定,加样回收率为98.05%(n=9,RSD=2.32%);16批海巴戟药材多糖含量为5.53%~12.63%,其多糖含量测定方法的合成不确定度为0.029 4~0.093 8,扩展不确定度为0.059 0~0.187 6。影响测量不确定度的主要因素有称量、浓度配制和吸光度。本研究建立的海南黎药海巴戟多糖含量测定方法适应性广、灵敏度高,若将测量结果不确定度纳入标准制定有助于对海巴戟药材含量分析方法的建立和质量标准的制定,有利于对海巴戟药材资源的开发。 相似文献
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Zhe Liu Xiaoying Yao Juan Du Baifen Song Feng Zhang 《Biological trace element research》2018,182(2):309-316
Dietary selenium (Se) deficiency is known to cause myodynia syndrome and Se influences immune responses by changing the expression of inflammatory cytokines and heat shock proteins (Hsps), but the details are not completely elucidated. In the present study, 72 1-day-old mice were divided into two groups; the first group was fed a Se-sufficient diet, while the second group was fed a Se-deficient diet. Skeletal muscles and blood samples were taken from all mice after 42 days of treatment. The activities of glutathione peroxidase (GPX) and glutathione (GSH), mRNA and protein expression levels of inflammatory cytokines (including TNF-α, inducible NO synthase, cyclooxygenase-2, and prostaglandin E synthases), protein expression levels of NF-κB, and the mRNA expression levels of Hsps in the skeletal muscles of mice were examined. The results showed that GPX and GSH activities were decreased, while the mRNA and protein expression levels of inflammatory cytokines and the mRNA levels of Hsps were increased by Se deficiency in mouse skeletal muscles. In the present study, the protective role of Se in oxidative stress, inflammatory cytokines, and Hsps in the skeletal muscles of mice was summarized. 相似文献