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121.
122.
基于共享式增长的视角,分析了贫困地区的农村在教育、开发经费、医疗保障及剩余劳动力转移中存在的问题,提出了相应的对策建议。 相似文献
123.
[目的]通过比较不同芽位马铃薯母薯生理代谢及根系形态的变化,分析了植物生长调节剂对马铃薯生长的调控效应。[方法]采用盆栽试验,浸种使用不同植物生长调节剂,研究母薯生理代谢及根系理化性状变化,探讨植物生长调节剂对马铃薯生育进程的影响。[结果]DTA-6可以提高顶部芽位母薯播后21 d内还原糖含量,对播后42~56 d根系长度、根系体积及根系干重均有提高的调控效应;DTA-6可以提高基部芽位母薯播后7~28 d内可溶性糖含量,但减少播后42~49 d根系干物质积累。SODM对顶部芽位母薯的调控效应与DTA-6基本相同,但是它对可溶性糖含量提高的效果好于DTA-6。就基部芽位母薯而言,SODM可以提高播后7~28 d内可溶性糖含量,降低播后42~49 d内根系干物质的积累,但调控效应较弱。[结论]植物生长调节剂能够通过调控马铃薯母薯生理代谢及根系形态的变化进而影响马铃薯生长发育进程。 相似文献
124.
蛋白质组学研究技术及其在果树学中的应用 总被引:7,自引:3,他引:7
蛋白质组研究是当今生命科学发展的一个新的增长点,它能阐明基因组所表达的真正执行生命活动的全 部蛋白质的表达规律和生物功能。简要介绍了蛋白质组学产生的科学背景、研究方法和研究内容。蛋白质组学研究 方法主要有双向聚丙烯酰胺凝胶电泳(2D-PAGE)、质谱(Mass-spectrometric)技术、蛋白质芯片(Protein chips)技术、酵母 双杂交系统(Yeast two-hybrid system)、双向高效柱层析和生物信息学等。其应用的范围包括植物群体遗传学、在个体 水平上植物对生物和非生物环境的适应机制、植物的发育和组织器官的分化过程,以及不同亚细胞结构在生理生态 过程中的作用等诸多方面。同时展望了植物蛋白质组学研究前景以及蛋白质组学技术在果树学中的应用前景。 相似文献
125.
王飞 《湖南农业大学学报(自然科学版)》2011,(2):95-100
十七年文学出于对革命意识形态的绝对捍卫,对土匪的想象缺少了民国时期作品的丰富性,其匪类叙事反映了主流意识形态对于文学匪色想象的绝对控制和规训。然而传统英雄侠义观的根深蒂固以及古典英雄传奇叙事模式的影响使匪色想象逸出意识形态的控制,塑造了新的类型形象——具有匪性气质的革命英雄人物。同时在十七年文学中还存在一个异数——那就是诗人郭小川的叙事长诗《一个和八个》,它体现了逸出秩序之外的个性化匪色想象,也使诗人因此受到严厉的政治批判。 相似文献
126.
The prognosis of liver cancer was inferior among tumors. New medicine treatments are urgently needed. In this study, a novel exopolysaccharide EPS364 was purified from Vibrio alginolyticus 364, which was isolated from a deep-sea cold seep of the South China Sea. Further research showed that EPS364 consisted of mannose, glucosamine, gluconic acid, galactosamine and arabinose with a molar ratio of 5:9:3.4:0.5:0.8. The relative molecular weight of EPS364 was 14.8 kDa. Our results further revealed that EPS364 was a β-linked and phosphorylated polysaccharide. Notably, EPS364 exhibited a significant antitumor activity, with inducing apoptosis, dissipation of the mitochondrial membrane potential (MMP) and generation of reactive oxygen species (ROS) in Huh7.5 liver cancer cells. Proteomic and quantitative real-time PCR analyses indicated that EPS364 inhibited cancer cell growth and adhesion via targeting the FGF19-FGFR4 signaling pathway. These findings suggest that EPS364 is a promising antitumor agent for pharmacotherapy. 相似文献
127.
Energy partitioning in cultured juvenile Pacific bluefin tuna,Thunnus orientalis (Temminck & Schlegel, 1844) 下载免费PDF全文
Takayuki Ohnishi Amal Biswas Kohshi Kaminaka Takahiro Nakao Masashi Nakajima Noboru Sakakibara Kenji Takii 《Aquaculture Research》2016,47(7):2040-2049
The characteristics of dietary utilization, energy conversion efficiency, metabolic rate and energy partitioning were measured for cultured Pacific bluefin tuna (PBT) juveniles fed on an artificial diet. Thirty‐one juveniles (1.1 ± 0.3 g BW) were stocked into each of two 2500 L tanks to measure oxygen consumption (?O2), swimming speed, digestibility and growth performance. ?O2 elevated until 2.5 ± 0.3 times of pre‐feeding level within 1.5 h after feeding, except for the first feeding, and returned to pre‐feeding level within 3 h. Swimming speed fluctuation was corresponded with the ?O2 fluctuation, and both parameters were stable from 02:00 to 06:00 and also during the whole day for starved fish. These indicate that feeding has strong influence on their metabolic rate. Energy partitioning for faecal, urinary and branchial, heat increment and voluntary activity, standard metabolism, and retained energy were calculated to be 17.2%, 5.9%, 14.9%, 41.3% and 20.7% of total ingested energy, respectively. The results indicate that, unlike other fish, juvenile PBT distribute large amount of energy for maintenance, which allows only a little proportion of ingested energy available for growth. 相似文献
128.
Marina Do Souto Daniel R. Brown Valeria Segura Rubn Negri Brenda Temperoni Georgina Cepeda Maria D. Vias Fabiana L. Capitanio Marina V. Diaz 《Fisheries Oceanography》2019,28(5):597-611
Dynamics of clupeiform fish populations such as anchovy are frequently impacted by environmental variations which can affect the success of the species recruitment. Herein, we have analyzed recent otolith growth rate, RNA/DNA nutritional condition index (sRD), and mortality rate of argentine anchovy larvae Engraulis anchoita from three different nursery areas in the Southwest Atlantic. We have evaluated the relationship between the environmental variables (abundance of copepod nauplii, temperature, chlorophyll‐a concentration, and abundance of E. anchoita larvae) and larval endogenous variables (size, weight, age, and otolith radius) to sRD and recent growth rate. Fast larval growth rates were observed toward the northern sector of the studied area, characterized by higher temperature. High values of sRD were associated with higher nauplii abundance in the proximity of coastal fronts. The larvae with the lowest growths and lowest minimum values of nutritional condition coincided with the area where there was less abundance of nauplii and higher larval mortality. Larval size and nauplii abundance were positive explanatory factors for both recent growth rate and sRD index. Temperature had a positive effect on recent growth rate and a negative effect on sRD index. This condition index was poorly explained in terms of model fit in comparison with the growth model. The results herein provided could be significant to better understand the recruitment of the species, as to determining favorable areas for the growth and survival of anchovy larvae. 相似文献
129.
130.
针阔混交异龄林生长规律的研究 总被引:6,自引:0,他引:6
本文分析了闽北针阀混交异龄林的层次结构、年龄结构、直径分布、更新情况以及林分生长量.采用林分解析法模拟各林层树木的主要调查因子间的关系,初步了解了闽北针阀混交异龄林的生长规律. 相似文献