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71.
十六个水稻品种(系)对褐飞虱的抗虫性评价   总被引:3,自引:0,他引:3  
本文通过苗期抗性鉴定、田间抗虫性鉴定、稻田节肢动物功能团优势度比较及产量测定的方法来评价16个水稻品种(系)对褐飞虱Nilaparvata lugens(Stl)的抗性。结果表明,有12个品种(系)对褐飞虱表现为抗级,2个品系表现为中抗。这14个抗虫-中抗的品种(系)在成株期也表现一定的抗虫性,且与对照TN1之间差异显著。本试验条件下,广占63-3S/华恢15、广两优106、Y58S/华15、广两优476、广占63-4S/华恢15这5个品种(系)不仅抗虫性好,而且产量也较高,分别比TN1和主栽品种扬两优6号高63.49%~66.57%和3.47%~11.57%,具有广泛的开发应用前景。  相似文献   
72.
目的 探讨规范化培训与量化绩效考核对手术室感染率的影响。方法 2012年1—12月对我院手术室护理人员进行规范化培训并实施量化绩效考核,与2011年1—12月感染率情况进行比较。结果 对手术室护理人员规范化培训,采取量化绩效考核之后,手术室感染率由1.46%下降到0.70%P=0.001)。结论 在护理管理中对护理人员进行规范化培训,并绩效考核量化其工作内容,能够调动其工作积极性,降低手术室感染率并提高护理服务质量。  相似文献   
73.
广西灵川县种植业的可持续发展   总被引:1,自引:0,他引:1  
广西是我国南方农业大省(区),明确其农业发展的制约因素,提出具体的解决措施,实现农业可持续发展,对解决农业、农村和农民问题,促进经济持续、快速、健康发展,实现社会主义现代化建设战略目标具有重要的理论和现实意义。主要采用了参与性农户评估方法(PRA),通过随机入户方式,与农户面对面交流,并结合调查问卷,对广西桂林市灵川县11个乡镇的农户进行了调查访问,为方便研究和数据处理,在数据分析过程中将该县11个乡镇分为3个片区:东部片区、中部片区、北部片区,对比3组农户的文化素质、种植制度、冬季农业现状、农业需求和农田水利设施等方面问题,探讨广西农业可持续发展的制约因素,并提出相应的对策,以期为广西农业可持续发展提供理论依据。调查结果表明,虽然目前灵川县农业取得众多发展成就,但仍存在以下几个方面的问题,严重影响了该县种植业可持续发展的进程。一是种植制度结构单一,二是冬季农业发展薄弱,三是种植技术贫乏,四是基础设施建设不完善等,因此,为促进灵川县种植业可持续发展,亟需采取以下对策和措施:调整作物种植结构,建立合理的种植制度;大力发展冬季农业;满足农民最迫切的农业需求;加强农业基础设施建设等。  相似文献   
74.
cis-Prenyltransferases (CPTs) comprise numerous enzymes synthesizing isoprenoid hydrocarbon skeleton with isoprenoid units in the cis (Z) configuration. The chain-length specificity of a particular plant CPT is in most cases unknown despite the composition of the accumulated isoprenoids in the tissue of interest being well established. In this report AtCPT6, one of the nine Arabidopsis thaliana CPTs, is shown to catalyze the synthesis of a family of very short-chain polyisoprenoid alcohols of six, seven, and eight isoprenoid units, those of seven units dominating. The product specificity of AtCPT6 was established in vivo following its expression in the heterologous system of the yeast Saccharomyces cerevisiae and was confirmed by the absence of specific products in AtCPT6 T-DNA insertion mutants and their overaccumulation in AtCPT6-overexpressing plants. These observations are additionally validated in silico using an AtCPT6 model obtained by homology modeling. AtCPT6 only partially complements the function of the yeast homologue of CPT-Rer2 since it restores the growth but not protein glycosylation in rer2Δ yeast. This is the first in planta characterization of specific products of a plant CPT producing polyisoprenoids. Their distribution suggests that a joint activity of several CPTs is required to produce the complex mixture of polyisoprenoid alcohols found in Arabidopsis roots.  相似文献   
75.
All systemically administered glucocorticoids (GC) are prohibited in-competition, because of the potential ergogenic effects. Although short-term GC intake has been shown to improve performance during submaximal exercise, literature on its impact during brief intense exercise appears to be very scant. The purpose of this study was to examine the ergogenic and metabolic effects of prednisone during repeated bouts of high-intensity exercise. In a double-blind randomized protocol, ten recreational male athletes followed two 1-week treatments (Cor: prednisone, 60 mg/day or Pla: placebo). At the end of each treatment, they hopped on their dominant leg for 30 s three times consecutively and then hopped until exhaustion, with intervals of 5 min of passive recovery. Blood and saliva samples were collected at rest and 3 min after each exercise bout to determine the lactate, interleukin-6, interleukin-10, TNF-alpha, DHEA and testosterone values. The absolute peak force of the dominant leg was significantly increased by Cor but only during the first 30-s hopping bout (p < 0.05), whereas time to exhaustion was not significantly changed after Cor treatment vs Pla (Pla: 119.9 ± 24.7; Cor: 123.1 ± 29.5 s). Cor intake lowered basal and end-exercise plasma interleukin-6 and saliva DHEA (p < 0.01) and increased interleukin-10 (p < 0.01), whereas no significant change was found in blood lactate and TNF-alpha or saliva testosterone between Pla and Cor. According to these data, short-term glucocorticoid intake did not improve endurance performance during repeated bouts of high-intensity exercise, despite the significant initial increase in absolute peak force and anti-inflammatory effect.  相似文献   
76.
植物雌雄株性别鉴定研究方法的评价   总被引:11,自引:1,他引:10  
综述了近50年来国内外关于植物雌雄株性别鉴定各种常用方法的研究新进展,并就各种方法的优缺点加以讨论,同时提出建议。  相似文献   
77.
The aim of this study was to assess objectivèly the processes of mental rehearsing (imagery) by measuring variations of the autonomic nervous system (or ANS responses) during an open-ended complex motor skill in two actual experiments (volleyball) and during mental rehearsing taking place between them. Comparison between pre- and post-test (volleyball) scores related to imagining and non-imagining performances revealed significant improvement in the former (2=20.9, P<0.00001) while in the latter 2=27, P<0.9, NS. The ANS parameters (skin potential and resistance, skin temperature and heat clearance, instantaneous heart rate and respiratory frequency) were quantified by original techniques and indices. Results from a principal component analysis showed a strong correlation between the responses in actual tasks (pre- and post-test volleyball) and during mental imagery, since the same preferential variables appeared on the main axis in 87% of cases. Thus the same autonomic channels seemed to be used during the actual activity and during the mental imagery of this activity. So far as phasic results were concerned, the main finding was a differing development of skill between imagining and non-imagining volleyball players. No clear difference was seen between pre- and post-tests in non-imaginers, except an increase in the median of the duration of the response observed in heat clearance, m1 and m2 respectively [m1= 5.8 (SD 4.1) s, m2= 7.6 (SD 3.9) s, P<0.001]. Conversely, for other ANS parameters, a significant decrease was seen in the post-test responses compared to pre-test responses in the imagining group [for instance, the median of the duration of the resistance responses decreased from m1= 12.6 (SD 4.3) s, and m2= 7.8 (SD 4.5) s, P<0.0001 in imaginers, while no change was observed in non-imaginers: 9.6 (SD 6.0) s vs 9.5 (SD 6.1) s, NS] except in the duration of the heat clearance response where an␣increase was seen [m1= 7.3 (SD 5.0) s vs m2= 7.6 (SD␣3.1) s, NS]. Compared to the non-imagining group, the latter result may also have been associated with a response decrease in the imagining group. Thus mental rehearsing induced a specific pattern of autonomic response: decreased amplitude, shorter duration and negative skin potentials compared to the control group. As this pattern was associated with better performance in the tests it can be suggested that in the case of open-ended motor activity, mental rehearsing may help in the construction of schema which can be reproduced, without thinking, in actual practice. Thus a neural information process might develop in the central nervous system changing from a parallel into a serial treatment. Accepted : 23 October 1997  相似文献   
78.
国家财政部于2009年印发了《国家重点生态功能区转移支付(试点)办法》,中央财政开始以转移支付的方式对国家重点生态功能区进行生态补偿,截止到2020年国家已累计下达转移支付资金6035.5亿元。评估国家重点功能区财政转移支付的生态保护成效对国家生态环境保护与修复决策具有重要意义,以国家重点生态功能区转移支付县域为调查和评估对象,基于多期遥感解译的土地利用/土地覆被数据,对正式实施财政转移支付政策以来国家重点生态功能区生态系统格局及其变化进行了评估,并对是否接受财政转移支付县域生态系统格局变化进行了对比分析。研究结果表明:国家重点生态功能区生态质量状况整体好转,2011—2019年土地覆被转类指数为3.85%,生态质量整体上好转主要与水域增加有关。享受国家财政转移支付政策后各县域生态质量改善明显,从2011—2016年的空间横向比较来看,享受财政转移支付县域土地覆被转类指数为2.28%,未享受县域为-3.36%;从2011—2019年的时间纵向比较来看,享受财政转移支付前土地覆被转类指数为-3.35%,而享受后为1.70%。然而,国家重点生态功能区人为活动干扰仍然较为强烈,研究时段内城乡...  相似文献   
79.
The importance of copper–ethanolamine-based wood preservatives is increasing. These preservatives usually consist of copper as a fungicide, ethanolamine as a fixative, and secondary fungicides (boron, triazoles) and other additives (water repellents, fixatives, wax emulsions, etc.). Questions arise as to how each of these ingredients interacts with wood-decay fungi, and whether there are any synergistic effects between the components. In order to elucidate these questions, Norway spruce wood specimens were impregnated with five different aqueous solutions consisting of one single component only and of complete formulation of five different concentrations. These specimens were exposed to two brown-rot fungi, Antrodia vaillantii and Gloeophyllum trabeum, as well as to the white-rot fungus Trametes versicolor for 8 weeks according to mini block procedure. In parallel, petri dishes with nutrient medium containing different quantities of ingredients and of complete wood preservative were inoculated with the same fungal species, and their growth was compared with growth on media without chemicals. The results showed that both experimental methods give similar results. In general, there was no synergistic effect determined. Ethanolamine did not decrease fungicidal properties of the system, while on the other hand octanoic acid has a positive effect on the growth of brown-rot fungi. The minimal effective concentration of tested copper–ethanolamine preservative was determined by the minimum effective concentration of the most fungi-toxic ingredient.  相似文献   
80.
This paper presents a methodology that helps managers evaluate how to assess the impact of postponement on supply chain performance considering logistics and ecological criteria. We consider a green supply chain design that considers CO2 transport emissions under different postponement strategy scenarios using a simulation tool. The paper focuses on a relevant extension of postponement theory by including green considerations into the evaluation of postponement strategies in green supply chain design. Moreover, it provides some insight on how to measure and evaluate the impact of postponement regarding supply chain transport performance, considering different transport mode (container ocean ship and truck) using the European Platform on Life-Cycle Assessment (EPLCA) of ELCD – European Life-Cycle Database. The study has demonstrated that logistics and packing postponement strategies can improve the performance of logistics (total inventory and order lead-time) and, at the same time contribute to reducing the environmental impact of CO2 emissions from transportation process.  相似文献   
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