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1.
Alessandra Bertoli Anthea LoBue Luca Quattrini Stefania Sartini Beatrice Polini Sara Carpi Francesco Paolo Frontini Graziano Di Giuseppe Graziano Guella Paola Nieri Concettina La Motta 《Marine drugs》2022,20(11)
Euplotin C is a sesquiterpene of marine origin endowed with significant anti-microbial and anti-tumor properties. Despite the promising functional profile, its progress as a novel drug candidate has failed so far, due to its scarce solubility and poor stability in aqueous media, such as biological fluids. Therefore, overcoming these limits is an intriguing challenge for the scientific community. In this work, we synthesized β-cyclodextrin-based nanosponges and investigated their use as colloidal carriers for stably complex euplotin C. Results obtained proved the ability of the carrier to include the natural compound, showing remarkable values of both loading efficiency and capacity. Moreover, it also allowed us to preserve the chemical structure of the loaded compound, which was recovered unaltered once extracted from the complex. Therefore, the use of β-cyclodextrin-based nanosponges represents a viable option to vehiculate euplotin C, thus opening up its possible use as pharmacologically active compound. 相似文献
2.
西藏降水化学分析 总被引:3,自引:0,他引:3
1987-1988年及1997-2000年间,在西藏拉萨、定日、当雄、安多采集降雨样品及部分大气浮尘样品,分析测定了pH、电导率、CO2分压、总悬浮颗粒含量及10多种离子浓度。共测量了300场次降雨的pH值、电导率和其中60场次降雨的化学成分含量。结果显示:青藏高原降雨常呈弱碱性,1987-1988年间加权平均pH值为8.36,1997-1999年间为7.5。造成高原降雨呈弱碱性的主要原因是来自地面富含钙的粉尘。西藏是世界上空气污染最轻的地方,但是从20世纪80-90年代的降雨中,NO3^-与SO4^2-含量增加,pH值降低,表明保护这片脆弱环境的紧迫性。 相似文献
3.
4.
采用平板计数法和聚合酶链式反应( PCR)-变性梯度凝胶电泳( DGGE)技术分析免疫增强剂党参对仿刺参( Apostichopus japonicas)肠道菌群结构的影响。将初始体重为(18.00±2.00) g的仿刺参随机分为2组(对照组、试验组),每组6个重复,每个重复12只。对照组投喂海泥、鼠尾藻粉按照1∶1的质量比配制的饵料,试验组饵料中以鼠尾藻粉质量的2%添加党参,连续投喂28 d。结果表明:应用免疫增强剂党参不仅能够显著提高仿刺参的特定生长率( P<0.05),降低其饵料系数(P<0.05),而且能够显著增加仿刺参肠道内容物中异养菌的数量(P<0.05);序列统计分析显示投喂党参后仿刺参肠道细菌优质序列比例显著增加( P<0.05),试验组达97.57%,对照组仅为80.22%;Beta多样性分析反映投喂党参后仿刺参肠道微生态环境发生了变化,其多样性系数范围在14.91%~15.47%、15.47%~16.21%、14.91%~16.21%;丰度分析显示投喂党参后仿刺参肠道内容物中变形菌门( Proteobacteria)和拟杆菌门( Bacteroidetes)丰度提高,疣微菌门( Verrucomicrobia)、放线菌门( Actinobacteria)和厚壁菌门( Firmiaites)丰度降低;聚类分析显示试验组与对照组肠道菌群结构相似性系数为0.97。由此可见,免疫增强剂党参可提高仿刺参的特定生长率,降低饵料系数,增加肠道异养菌数量和优势菌群丰度,优化肠道微生态环境。 相似文献
5.
Hidalgo Carcedo C Bonazzi M Spanò S Turacchio G Colanzi A Luini A Corda D 《Science (New York, N.Y.)》2004,305(5680):93-96
Organelle inheritance is an essential feature of all eukaryotic cells. As with other organelles, the Golgi complex partitions between daughter cells through the fission of its membranes into numerous tubulovesicular fragments. We found that the protein CtBP3/BARS (BARS) was responsible for driving the fission of Golgi membranes during mitosis in vivo. Moreover, by in vitro analysis, we identified two stages of this Golgi fragmentation process: disassembly of the Golgi stacks into a tubular network, and BARS-dependent fission of these tubules. Finally, this BARS-induced fission of Golgi membranes controlled the G2-to-prophase transition of the cell cycle, and hence cell division. 相似文献
6.
The production of agglutinins to Salmonella typhi was studied in the opossum embryo in the period immediately before and after the development of thymic and lymph node lymphoid tissue. Antibody was found only in embryos older than 8 days which corresponds to an 8- to 10-week human embryo in terms of organogenesis and is the earliest stage at which antibody production has been recorded. 相似文献
7.
香草兰营养特性的研究 总被引:6,自引:3,他引:6
对海南不同生产水平的香草兰种植园植株的养分调查分析,及N,P,K,Ca,Mg肥料的盆栽试验,研究香草兰的营养特性。结果表明,香草兰植株养分的吸收量以K〉Ca〉N〉Mg〉P,叶片以Ca〉K〉N〉Mg〉P;结果植株养分吸收量N:P:K:Ca:Mg=1.00:0.24,1.39:1.18:0.48,盆栽幼苗N:P:K:Ca:Mg=1.00:0.10:1.38:1.23:0.33;高产园植株Ca,P含量极 相似文献
8.
杂交相思组织培养研究初报 总被引:1,自引:0,他引:1
【目的】筛选杂交相思组织培养不同培养阶段的培养基配方,为实现杂交相思工厂化育苗提供技术参考。【方法】用杂交相思嫩茎为外植体,探究生长调节剂6-BA、NAA、IBA对其诱导出芽、继代增殖和诱导生根的效果。【结果】在不添加6-BA的情况下,添加0.2mg/LNAA时芽诱导率为60.0%,当添加0.2mg/L的6-BA后,诱导率为42.0%。当NAA为0~0.5mg/L时,随着6-BA的增加,增殖系数随之增加,6-BA为0.8mg/L时,增殖系数为4.2;当6-BA为1.0mg/L以上时,继代苗的增殖系数为1.0。以改良MS为基本培养基,在NAA1.0mg/L的条件下添加0.5、1.0mg/L的IBA生根诱导率分别为17.5%、24.0%;以改良1/2MS为基本培养基,在NAA1.0mg/L的条件下,添加0.5mg/L的IBA生根率为91.7%,当添加IBA为1.0mg/L时,生根率降到50.0%;生根苗移栽基质以黄心土与河沙或蛭石混合较好,移栽成活率在85.0%以上。【结论】改良MS+NAA0.2mg/L培养基是较适宜芽诱导的培养基;改良MS+6-BA0.8mg/L+NAA0.5mg/L培养基较利于继代苗的生长;改良1/2MS+NAA1.0mg/L+IBA0.5mg/L培养基较改良MS培养基有利于诱导生根。 相似文献
9.
油菜蚜虫是油菜上一种常发性的害虫,常年发生较重,油菜蚜虫对油菜的危害一是直接取食为害,二是传播病毒病,世代重叠危害,严重影响产量。本文论述了油菜蚜虫的生活习性、危害发生情况、控制虫害发生的原则、防治方法等。并提出了防止油菜蚜虫危害工作的建议。 相似文献
10.
Webster MJ Goodband RD Tokach MD Nelssen JL Dritz SS Woodworth JC De La Llata M Said NW 《Journal of animal science》2003,81(8):2032-2040
We conducted two experiments comparing the use of extruded-expelled soybean meal (EESoy) to solvent-extracted soybean meal (SBM) in swine diets. In Exp. 1, the objective was to determine the optimal processing temperature of EESoy for nursery pig growth performance. Pigs (n = 330, 13.2 +/- 2.3 kg of BW) were fed a control diet containing SBM with added fat or one of five diets containing EESoy extruded at 143.3, 148.9, 154.4, 160.0, or 165.6 degrees C. All diets were formulated on an equal apparent digestible lysine:ME ratio. From d 0 to 20, no differences were observed (P > 0.32) in ADG or ADFI (average of 544 and 924 g/d, respectively). However, gain:feed ratio (G/F) improved (quadratic, P < 0.01, range of 0.56 to 0.60) with increasing processing temperature, with the greatest improvement at 148.9 degrees C. In Exp. 2, the objective was to determine the feeding value of EESoy relative to SBM with or without added fat for growing-finishing pigs in a commercial production facility. A total of 1,200 gilts (initially 24.5 +/- 5.1 kg of BW) was used, with 25 pigs per pen and eight replications per treatment. Dietary treatments were arranged in a 2 x 3 factorial, with two sources of soybean meal (SBM or EESoy) and three levels of added fat. Pigs were phase-fed four diets over the experimental period and added fat (choice white grease) levels were 0, 3.4, and 7% initially, with the added fat levels decreasing in the next three dietary phases. Energy levels were based such that the higher energy in EESoy (with or without added fat) was calculated to be equal to that provided by SBM with added fat. From 24.5 to 61.2 kg, pigs fed EESoy had greater (P < 0.07) G/F than those fed SBM. Increasing added fat in either EESoy- or SBM-based diets increased G/F (linear, P < 0.0003). From 61.2 to 122.5 kg, ADG and G/F were unaffected in pigs fed EESoy and/or increasing added fat (P > 0.10). For the overall growing-finishing period, ADG was unaffected (P > 0.61) by increasing energy density of the diet; however, ADFI decreased (P < 0.05) and G/F increased (P < 0.02, range of 0.37 to 0.40) as energy density increased with either EESoy or added fat. Carcass leanness was not affected by dietary treatment. These results indicate that EESoy should be extruded at 148.9 to 154.4 degrees C, and that increasing dietary energy density by using EESoy and/or added fat improves feed efficiency in finishing pigs reared in a commercial environment. 相似文献