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81.
82.
Brook L Nunn Scott A Shaffer Alexander Scherl Byron Gallis Manhong Wu Samuel I Miller David R Goodlett 《Briefings in Functional Genomics and Prot》2006,5(2):154-168
Shotgun proteomics is rapidly becoming one of the most efficient and popular tools to examine protein expression in cells. Numerous laboratories now have a wide array of low- and high-performance mass spectrometry instrumentation necessary to complete proteome-wide projects. Often these laboratories have time and financial constraints that prohibit all projects from being conducted on high-performance state-of-the-art mass spectrometers. Here, we compare shotgun proteomic results using a direct 'lyse, digest and analyse' approach on a high-performance mass spectrometer (i.e. the LTQ-FT) with the results from a much lower-performance instrument (i.e. the LCQ-DUO) where, for the latter, various traditional protein pre-fractionation steps and gas-phase fractionation were used to increase the proteome coverage. Our results demonstrate that shotgun proteomic analyses conducted on the lower-performance LCQ-DUO mass spectrometer could adequately characterize a PhoP constitutive strain of Salmonella typhimurium if proteome pre-fractionation steps and gas-phase fractionation were included. 相似文献
83.
Predator foraging may be affected by previous prey capture, but it is unknown how nutrient balance affects foraging behaviour. Here, we use a trap-building predator to test whether nutrients from previous prey captures affect foraging behaviour. We fed orb-weaving spiders (Zygiella x-notata) prey flies of different nutrient composition and in different amounts during their first instar and measured the subsequent frequency of web building and aspects of web architecture. We found that both the likelihood of web building and the number of radii in the web were affected by prey nutrient composition while prey availability affected capture area and mesh height. Our results show that both the balance of nutrients in captured prey and the previous capture rate may affect future foraging behaviour of predators. 相似文献
84.
害虫天敌的植物支持系统 总被引:7,自引:0,他引:7
保护天敌,使天敌长期有效地控制害虫是保护性生物防治的核心内容。其中,植物在维持和促进天敌控制害虫中的重要性和作用越来越受到关注。本文概述了各种支持天敌发挥效能的植物类群,论述了蜜源植物、储蓄植物、栖境植物、诱集植物、指示植物、护卫植物等在支持天敌生存和繁殖方面的生物功能,评述了研究和应用这些植物时需注意的问题,提出了科学利用这些植物以维持和增强农业生态系统中天敌发挥控害作用的植物支持系统,并指出了由于对这些植物类别的界定和定义模糊所带来的不便,给出了相应的建议。 相似文献
85.
目的为了及时诊断产后出血和正确测量剖宫产术中的失血量,及时补充血容量,降低孕产妇死亡率。方法同一剖宫术孕妇分别采用精测法(称重法和液血分流吸引器相结合)和目测法两种方法进行失血量的比较。结果目测法估算失血量明显低于精测法,结果显示用精测法对剖宫产术中进行失血量的估算是目测法的1.5倍(1.5:1)。结论在剖宫产术中精确测量失血量,及时诊断产后出血,有利于及时补充血容量,提高孕产妇身心健康。 相似文献
86.
Seymour Kaufman 《Neurochemical research》1991,16(9):1031-1036
Tetrahydrobiopterin and the folate coenzymes can reciprocally interact in ways that would be useful to the metabolic pathways subserved by both of these coenzymes. Thus, through one of the reactions catalyzed by methylene tetrahydrofolate reductase, 5-CH3-H4-folate can regenerate BH4 from q-BH2 and q-BH2 can provide an escape from the methyl trap.Special issue dedicated to Dr. Louis Sokoloff 相似文献
87.
D.J. Ward H. Van de Langemheen E. Koehne A. Kreidenweiss R.M.J. Liskamp 《Bioorganic & medicinal chemistry》2019,27(13):2857-2870
The development of a new class of cysteine protease inhibitors utilising the thiosulfonate moiety as an SH specific electrophile is described. This moiety has been introduced into suitable amino acid derived building blocks, which were incorporated into peptidic sequences leading to very potent i.e. sub micromolar inhibitors of the cysteine protease papain in the same range as the vinyl sulfone based inhibitor K11777. Therefore, their inhibitory effect on Schistosoma mansoni, a human blood parasite, that expresses several cysteine proteases, was evaluated. The homophenylalanine side chain containing compounds 27–30 and especially 36 showed promising activities compared with K11777 and warrant further investigations of these peptidic thiosulfonate inhibitors as new potential anti-parasitic compounds. 相似文献
88.
89.
Mating disruption method against the vine mealybug,Planococcus ficus: effect of sequential treatment on infested vines 下载免费PDF全文
Rakefet Sharon Tirtza Zahavi Tamar Sokolsky Carmit Sofer‐Arad Maor Tomer Rika Kedoshim Ally R. Harari 《Entomologia Experimentalis et Applicata》2016,161(1):65-69
The vine mealybug, Planococcus ficus (Signoret) (Hemiptera: Pseudococcidae), is a major pest of vineyards. Here, we tested the efficacy of the mating disruption method against the pest when applied during one or two successive years in high and low infestation levels. Following 1 year of treatment, at low initial infestation levels a shutdown of pheromone traps was observed, along with a significant reduction in infested vines. With initially high infestation levels, a gradual reduction in infested vines was observed, with a trap shutdown seen only after the second year of pheromone application. We discuss the implications of the male mating disruption method for this pest in which the wingless females are aggregated with limited movement among vines, offering multiple mating opportunities for the flying male. 相似文献
90.
A minnow trap that operates in various flow regimes in streams and allows sampling of small fish from stream bed microhabitats was developed. In laboratory and field tests, the most efficient trap design for capturing and retaining various species of fish had one funnel oriented downstream, a plexiglass body, and commercial trout food as bait. These lightweight traps can be set in a wide range of current velocities and depths, and can be useful in investigations that examine the microhabitat use, diel activity patterns or population densities of small lotic fish. Guidelines for the trap's use and for quick verification of capture success in new situations are suggested. 相似文献