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81.
Wang X  Li X  Li Y 《Biotechnology letters》2007,29(10):1599-1603
A more sensitive and convenient Coomassie Brilliant Blue (CBB) staining method for visualizing proteins was developed. Compared with the modifications include the supplement of 10% (v/v) methanol into the fixing solution, an increase of an additional sensitization step and CBB raised from 0.1 to 0.125%. The improved method can detect proteins at nanogram level. The improved method is more sensitive than Blue Silver and more convenient than the Silver protocol. Mass spectrometry results confirmed that it is suitable for subsequent proteomic research.  相似文献   
82.
83.
An absolute environmental sustainability assessment (AESA) addresses whether a production or consumption activity can be considered environmentally sustainable in an absolute sense. This involves a comparison of its environmental pressure to its allocated environmental carrying capacity. AESA methods have been developed in multiple academic fields, each using their own set of concepts and terms with little communication across the fields. A recent growing interest in using AESA methods for decision support calls for a better common understanding of the constituents of an AESA method and how it can be communicated to scientific peers and to potential users. With this aim, we develop a framework for AESA methods, composed of a succession of four assessment steps and involving six methodological choices that must be made by the method developer or the user. We then use the framework to analyze and compare five selected AESA methods that focus on the release of phosphorus and nitrogen to the environment. In this manner, we show that the framework is able to systematically differentiate AESA methods that initially appear to be similar. Intended users of the framework include (1) method developers communicating new AESA methods to academic peers or potential method users and (2) researchers comparing a group of existing AESA methods and communicating their differences to their peers and to potential users looking for guidance on method selection.  相似文献   
84.
三台核桃结实特性研究   总被引:3,自引:0,他引:3  
刘德良  张琴 《广西植物》2001,21(1):67-71
选择标准株 70株 ,其中有草果核桃 ( cv.Zaogu)、大油笼核桃 ( cv.Dayoulong)、早熟核桃 ( cv.Zaoshu)、小油笼核桃 ( cv. Xiaoyoulong)、荚绵核桃 ( cv. Jiamian) 5个品种。据对不同品种、海拔、年龄的结实特性研究 ,结果表明 :草果核桃是优良的栽培品种 ,早熟核桃结实性状表现最差 ,果枝粗是影响座果率最重要的因素。  相似文献   
85.
摘要 目的:探讨呼气末二氧化碳分压(PetCO2)、C-反应蛋白/白蛋白比值(CRP/Alb)及综合脱机指数(IWI)对重型颅脑损伤机械通气患者撤机失败的预测价值。方法:选择2020年1月至2022年6月在安徽中医药大学附属六安医院进行机械通气的重型颅脑损伤患者96例作为研究对象,按照撤机结局分为撤机失败组(n=31)和撤机成功组(n=65)。比较两组撤机前PetCO2、CRP/Alb、IWI及临床参数。应用多因素Logistic回归分析重型颅脑损伤机械通气患者撤机失败的危险因素。应用受试者工作特征(ROC)曲线评价PetCO2、CRP/Alb、IWI对重型颅脑损伤机械通气患者撤机失败的预测价值。结果:撤机失败组PetCO2、CRP/Alb、急性生理功能和慢性健康状况评分系统II(APACHE II)评分显著高于撤机成功组,机械通气时间长于撤机成功组,IWI、格拉斯哥昏迷评分(GCS)显著低于撤机成功组(P<0.05)。多因素Logistic回归分析显示,PetCO2≥37.01 mmHg、CRP/Alb≥0.97、IWI≤78.23、GCS≤5.90分、APACHE II评分≥26.17分、机械通气时间≥4.49 d是重型颅脑损伤机械通气患者撤机失败的危险因素(P<0.05)。ROC曲线分析结果显示PetCO2、CRP/Alb、IWI、GCS、APACHE II对重型颅脑损伤机械通气患者撤机失败均有较高的敏感度、特异度, PetCO2、CRP/Alb、IWI三项联合检测对重型颅脑损伤机械通气患者撤机失败预测的曲线下面积(AUC)高于PetCO2、CRP/Alb、IWI、GCS、APACHE II单独检测。结论:PetCO2、CRP/Alb及IWI联合评估对重型颅脑损伤机械通气患者撤机失败具有较高的预测价值。  相似文献   
86.
A computer technique for assessing blue-stained coated wood has been implemented for evaluating the discoloration of coatings and analysing the interior wood staining of samples subjected to testing according to European Standard EN 152. The comparison of visual assessment and computer-evaluated percentages of blue staining is based on a combination of correlation measures, principal components and cluster analysis. It appears difficult to imitate human evaluation with image processing, since computer ratings represent exact percentages, while subjective evaluations do not. Additionally, more specific techniques for exploring fungal growth in coated wood have been described. As EN 152 was specifically developed for testing efficacy of wood preservatives, a modified test methodology was elaborated for testing the efficacy of wood coatings, called here as the EN 152-reverse method. Furthermore three-dimensional (3D) reconstruction is validated as a tool for in-depth analysis of blue-stain disfigurement. This 3D visualisation indicates important differences in fungal infestation and proves its suitability for blue-stain resistance testing.  相似文献   
87.
Anouk Spelt  Lorien Pichegru 《Ibis》2017,159(2):272-284
Biased offspring sex ratio is relatively rare in birds and sex allocation can vary with environmental conditions, with the larger and more costly sex, which can be either the male or female depending on species, favoured during high food availability. Sex‐specific parental investment may lead to biased mortality and, coupled with unequal production of one sex, may result in biased adult sex ratio, with potential grave consequences on population stability. The African Penguin Spheniscus demersus, endemic to southern Africa, is an endangered monogamous seabird with bi‐parental care. Female adult African Penguins are smaller, have a higher foraging effort when breeding and higher mortality compared with adult males. In 2015, a year in which environmental conditions were favourable for breeding, African Penguin chick production on Bird Island, Algoa Bay, South Africa, was skewed towards males (1.5 males to 1 female). Males also had higher growth rates and fledging mass than females, with potentially higher post‐fledging survival. Female, but not male, parents had higher foraging effort and lower body condition with increasing number of male chicks in their brood, thereby revealing flexibility in their parental strategy, but also the costs of their investment in their current brood. The combination of male‐biased chick production and higher female mortality, possibly at the juvenile stage as a result of lower parental investment in female chicks, and/or at the adult stage as a result of higher parental investment, may contribute to a biased adult sex ratio (ASR) in this species. While further research during years of contrasting food availability is needed to confirm this trend, populations with male‐skewed ASRs have higher extinction risks and conservation strategies aiming to benefit female African Penguin might need to be developed.  相似文献   
88.
Summary Maternally inherited microorganisms that kill male (but not female) progeny are widespread in nature. Three hypotheses have been proposed for the evolution of male-killing microorganisms: inbreeding reduction, release of resources to remaining females and inoculum for horizontal transmission. The sonkiller bacterium,Arsenophonus nasoniae, is a maternally inherited bacterium that causes lethality of male embryos of infected females in the parasitoid wasp,Nasonia vitripennis. In this paper we describe the geographical distribution and frequency of the son-killer bacterium in North American populations ofN. vitripennis andNasonia longicornis. We tested the resource release hypothesis using the body size measurements of infected and uninfected females from natural populations. No evidence was found for a fitness increase of females infected with the bacterium compared to uninfected females. We propose a modification of the existing models, termed the incremental gain hypothesis. According to this model, the bacteria are maintained in host populations due to horizontal transmission and male killing provides an incremental gain in the fitness of infected females relative to females infected with non-male-killing bacteria.  相似文献   
89.
Given the demand for improved methods for detecting and characterizing RNA variants in situ, we developed a quantitative method for detecting RNA alternative splicing variants that combines in situ hybridization of fluorescently labeled peptide nucleic acid (PNA) probes with confocal microscopy Förster resonance energy transfer (FRET). The use of PNA probes complementary to sequences flanking a given splice junction allows to specifically quantify, within the cell, the RNA isoform generating such splice junction as FRET efficiency measure. The FRET-based PNA fluorescence in situ hybridization (FP-FISH) method offers a conceptually new approach for characterizing at the subcellular level not only splice variant isoform structure, location, and dynamics but also potentially a wide variety of close range RNA–RNA interactions. In this paper, we explain the FP-FISH technique workflow for reliable and reproducible results.  相似文献   
90.
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