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991.
992.
柑橘大实蝇成虫的翅载和额外负载能力 总被引:1,自引:0,他引:1
对柑橘大实蝇Bactrocera (Tetradacus) minax (Enderlein)的有效管理受阻于对其成虫运动行为的较少的认识。通过测定其成虫翅载能力和忍受额外负载重量的能力, 从而确定其成虫所携带不同的额外负载的电子标签重量对其正常起飞的影响程度, 为制作合适的昆虫谐波雷达的电子标签提供技术参数。其雌雄成虫的翅载能力并没有随着成虫个体重量增加而降低, 也没有因为性别不同而存在差异。成虫经过正常取食和饥饿(只喂清水)变化处理, 其成虫平均净载重量约为11 mg。来自网室成虫忍受额外负载试验结果表明, 成虫额外负载7.3 mg重量或为占其自身体重大约23%重量对于其向上起飞行为有较少或没有直接的影响。结果进一步表明, 在确定昆虫谐波雷达技术跟踪其成虫携带的电子标签适合性时, 选择的电子标签的重量不能超过7.3 mg。 相似文献
993.
侵染期的拟双角斯氏线虫Steinernema ceratophorum D43品系体外都包裹着一个透明的体鞘。为探明体鞘对线虫侵染力的影响, 了解鞘蛋白(sheath proteins, SPs)对大蜡螟Galleria mellonella 幼虫的免疫抑制作用, 本研究通过化学方法使拟双角斯氏线虫D43脱鞘, 以对寄主的致死率和侵入点数量为指标, 与包鞘线虫比较对大蜡螟幼虫的侵染力; 采用乙醇提取的方法获得线虫鞘蛋白, 利用双向电泳和质谱技术对鞘蛋白进行鉴定分析; 从血细胞数量和酚氧化酶活力两个方面评价鞘蛋白对大蜡螟幼虫免疫反应的抑制作用。结果表明: 0.5%次氯酸钠处理20 min可以保证95%以上的线虫存活和脱鞘。与包鞘线虫相比, 脱鞘线虫对大蜡螟幼虫的致死率显著降低, 致死时间延后, 节间膜侵入点数量显著减少。以35%乙醇提取的鞘蛋白提取物可鉴定出6种鞘蛋白, 其中一个被鉴定为丝氨酸蛋白酶。此外, 血腔注射鞘蛋白提取物可导致试虫血细胞数量明显降低, 酚氧化酶活力受到显著抑制。由此说明, 体鞘对拟双角斯氏线虫D43的侵染力具有显著影响, 鞘蛋白在抑制寄主昆虫免疫反应中发挥重要作用。 相似文献
994.
Yusuke Mimura Toshihiko Katoh Radka Saldova Roisin O Flaherty Tomonori Izumi Yuka Mimura-Kimura Toshiaki Utsunomiya Yoichi Mizukami Kenji Yamamoto Tsuneo Matsumoto Pauline M. Rudd 《蛋白质与细胞》2018,9(1):47
Glycosylation of the Fc region of IgG has a profound impact on the safety and clinical efficacy of therapeutic antibodies. While the biantennary complex-type oligosaccharide attached to Asn297 of the Fc is essential for antibody effector functions, fucose and outer-arm sugars attached to the core heptasaccharide that generate structural heterogeneity (glycoforms) exhibit unique biological activities. Hence, efficient and quantitative glycan analysis techniques have been increasingly important for the development and quality control of therapeutic antibodies, and glycan profiles of the Fc are recognized as critical quality attributes. In the past decade our understanding of the influence of glycosylation on the structure/function of IgG-Fc has grown rapidly through X-ray crystallographic and nuclear magnetic resonance studies, which provides possibilities for the design of novel antibody therapeutics. Furthermore, the chemoenzymatic glycoengineering approach using endoglycosidase-based glycosynthases may facilitate the development of homogeneous IgG glycoforms with desirable functionality as nextgeneration therapeutic antibodies. Thus, the Fc glycans are fertile ground for the improvement of the safety, functionality, and efficacy of therapeutic IgG antibodies in the era of precision medicine. 相似文献
995.
996.
Urban areas (especially cities) are challenged in meeting their direct water needs from local sources. They also exert strain on global water resources through their indirect (virtual) water use. Agencies concerned with urban water management have visions and goals for managing direct water use, but indirect use is only inferred in more global visions for sustainable consumption. There is limited quantification of “urban water performance” at the macro urban scale (whole of city) to monitor progress toward these goals. It is constrained by a lack of clarity about the evaluation approaches that best serve them. We ask, How can the evaluation approaches described in literature advance urban water management goals? We reviewed the utility of eight evaluation approaches, including urban water system modeling, urban metabolism (territorial and mass balance), consumption (life cycle assessment, water footprinting, and input‐output analysis), and complex systems (ecological network analysis and systems dynamics) approaches. We found that urban metabolism based on water mass balance is a core method for generating information to inform current goals for direct urban water use, with potential for being “coupled” with the other approaches. Consumption approaches inform the management of indirect water use. We describe this in a framework for urban water evaluation to give greater clarity to this field and flag the further research that would be needed to progress this. It includes the recommendation to differentiate the evaluation of direct and indirect urban water, but to also interpret them together. 相似文献
997.
Biological responses in Balb/c mice after long‐term parenteral administration of the light subunit of mushroom tyrosinase
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Wangsa T. Ismaya Alida Efthyani Raymond R. Tjandrawinata Heni Rachmawati 《Journal of biochemical and molecular toxicology》2017,31(11)
Light subunit of mushroom tyrosinase (LSMT) is a protein of unknown function from mushroom Agaricus bisporus that has been demonstrated to permeate through rat intestine ex vivo. Thus, it can be absorbed in the intestine, thereby holding a promise as a drug carrier for oral administration, similar to HA‐33 protein from botulinum, one of the closest structural homologs of LSMT. However, the safety of LSMT should be ensured prior to its use. Here, we described biological response of LSMT upon weekly intraperitoneal administration of 50 μg/day to the Balb/c mice for 12 weeks. Motoric and behavior profiles, as well as the index of main organs (liver, spleen, lung, heart, and kidney), and body weight, were not significantly changed as compared with the control group. Also, no IgG was detected in the serum. The results suggest that LSMT is safe for further development. 相似文献
998.
Background: Kallistatin, a serine proteinase inhibitor, has vasodilatory and anti-inflammatory properties and is increased in other inflammatory conditions. We measured kallistatin in HIV for the first time, examined its relationship with inflammation, and determined if statin therapy affected levels.
Methods: Kallistatin levels were measured in subjects from a randomized, double-blinded, placebo-controlled trial.
Results: One hundred and thirty-five HIV-infected subjects were included. Kallistatin levels were 28.4?μg/mL at baseline and not affected by rosuvastatin. Levels were correlated with high-sensitivity C-reactive protein (hsCRP), interleukin-6, fibrinogen and insulin resistance.
Conclusions: Kallistatin levels were correlated with some markers of systemic inflammation and should be further explored in the HIV population. 相似文献
999.
1000.
为探讨TLR9激动剂对疟疾体液免疫记忆的影响,用非致死型约氏疟原虫感染BALB/c小鼠,感染前2 d注射TLR9激动剂CpGl826,90 d后进行二次感染。薄血膜染色法观察红细胞感染率,流式细胞术检测脾细胞悬液中记忆性和活化性B细胞百分比,双夹心ELISA法检测特异性抗体水平。结果显示,二次感染前,TLR9激动剂处理鼠记忆性和活化性B细胞以及抗体水平略高于对照组;二次感染后,其再感染发生率和虫血症水平均略低于对照组;活化性B细胞和抗体以及记忆性B细胞也分别于二次感染后1 d和3 d出现了有意义的升高,且升高幅度均略高于对照组。表明TLR9激动剂对约氏疟原虫感染后体液免疫记忆的建立和维持有一定促进作用。 相似文献