槲皮素单硫酸酯和5’-氯-5’-脱氧腺苷单用与合用对凝血酶诱导兔血小板聚集的影响

目的：研究槲皮素单硫酸酯和5’-氨-5’-脱氧腺苷合用对凝血酶诱导兔血小板聚集的影响。方法：用比浊法检测血小板聚集。结果：槲皮素单硫酸酯和5’-氨-5’-脱氧腺苷对凝血酶诱导的兔血小板聚集都有抑制作用，两者合用作用增加。结论：槲皮素单硫酸酯与5’-氨-5’-脱氧腺苷具有协同抗血小板聚集的作用。     

The effect of surface growth of blue-green algae and bryophytes on some microbiological,biochemical, and physical soil properties

Summary The influence of surface growth of inoculated cyanobacteria (blue-green algae) on subsurface properties of a brown earth, silt loam soil was studied in reconstituted flooded soil columns. One blue-green algae species, Nostoc muscorum, become dominant within the first 7 days of inoculation. In light control columns (not inoculated) a bryophyte, Barbula recurvirostra, was dominant although significant growth of indigenous blue-green algae occurred. The blue-green algae counts were in the range of 1×10⁶ g^-1 dry soil in the surface layer (0–0.7 cm) in both columns. Any effect of surface phototrophic growth on soil properties was restricted to the surface layer. In inoculated columns there was a twofold increase in microbial biomass and an eightfold increase in bacterial numbers by week 13. However, bacterial numbers declined so that there was only a 2.8-fold increase by week 21. Dehydrogenase (x2.1), urease (x2.8) and phosphatase (x3.1) activities and polysaccharides (+69%) increased by week 21 as a result of the blue-green algae inoculation along with a significant improvement in soil aggregation. However, similar increases occurred in the light control columns, indicating that given appropriate conditions of light and moisture indigenous species may be ultimately as effective as introduced species in bringing about biochemical and microbiological changes to soil.     

Index of soil aggregates stability as linear function value of transition matrix elements

The paper presents a new index which is an innovative tool for the analysis of soil aggregates stability. The soil aggregates stability index (ASI) is based on a linear function value of transition matrix elements with coefficients being properly chosen weights. Each element of the transition matrix is a frequency (empirical probability) of aggregates transition from one class of size to another or within the same class. The proposed weights give an ASI value range from 1 to 32 and are thus formulated: a higher ASI value corresponds to a higher aggregates stability. The usefulness of the proposed index is illustrated in the case three soils (Haplic Phaeozem, Mollic Gleysol and Orthic Rendzina) for which aggregate water stability was determined by three different methods.     

蚜虫性信息素

蚜虫报警信息素 [(E)-β-farnesene,简称EBF] 是蚜虫腹管分泌的一种物质,它能对同种其他个体产生报警反应,使其迅速逃离危险现场。作为天然蚜虫信息素,EBF通过蚜虫嗅觉系统的气味结合蛋白OBPs和嗅觉受体ORs发挥作用,具有驱避、杀蚜、增效等多种生物活性,可用于蚜虫的行为调控,但由于其结构中存在的共轭双键而导致其稳定性差,从而限制了其实际应用。本文在简介蚜虫报警信息素EBF的基础上,系统介绍了EBF的结构修饰和改造进展,并对EBF及其类似物的生物活性和作用机制进行了综述,最后对EBF及其类似物的应用前景进行了展望,期望为开发具有实用价值的生态友好型蚜虫控制剂提供参考。     

2018年夏季南奥克尼群岛南极磷虾集群特征

基于2018年夏季南奥克尼群岛南极磷虾资源声学调查数据,本研究对该海域南极磷虾集群进行了分析。结果显示,检测到南极磷虾集群3 224个,反映集群特征的5个参数即深度、长度、厚度、面积及密度分别为(96.00±64.33) m、(218.52±455.66) m、(11.19±13.98) m、(1 894.40±9 345.72) m2和(114.11±159.60)尾/m³;不同时间段之间集群密度无显著性差异,但集群深度、长度、厚度及面积之间均存在显著性差异。不同水层间集群厚度和面积之间无显著性差异,但集群深度,长度和密度均存在显著性差异。南极磷虾集群共分为三类,其中第Ⅰ类集群密度最大,为(325.90±221.30)尾/m³;集群规模最小,为(379.64±433.73) m²;深度最深,为(158.06±67.54) m。第Ⅱ类集群的长度最长,为(1 089.60±1 189.56) m;集群面积为(15 601.25±30 243.33) m²,远大于其他集群。第Ⅲ类集群深度最浅,为(78....     

贵州大沙河自然保护区银杉种群结构初步研究

在大沙河自然保护区银杉踏查和设置样地调查的基础上,采用分布系数（Cx）法和扩散指数（Iq）法对银杉种群的结构和空间分布格局进行分析,结果表明,大沙河银杉种群总体上是一种不完全种群,特别是一些中等大小径级缺失使之成为一种不连续种群,但在不同群落银杉种群又表现出一定程序的多元化,即在某些群落中亦可以一种进展种群的形式存在,银杉种群的空间分布格局多为集群分布。大沙河自然保护区银杉种群的空间分布格局显示出与重庆金佛山、湖南八面山银杉种群的空间分布格局有相似的变化规律,但也有不同之处,金佛山的银杉-石栎群落和八面山的银杉-木荷群落中的银彩种群多为随机分布。     

桃小食心虫的危害及其防治研究进展

桃小食心虫是我国最严重的蛀果害虫之一,利用其性信息素进行防控,具有高效、环保及不易产生抗性等优点。天然桃小食心虫性信息素 (Z)-12-十九碳烯-9-酮与(Z)-13-二十碳烯-10-酮在昆虫体内含量极低,通过人工提取无法满足大规模防治需求。本研究以3-溴-1-丙醇为原料,经四氢吡喃基 (THP) 保护、亲核取代、Brown P2-Ni还原 (Ni(OAc)₂与NaBH₄催化氢化) 、格氏试剂加成与重铬酸吡啶鎓 (PDC) 氧化等7步反应,构建了一种高效合成桃小食心虫性信息素的方法;并首次将Brown P2-Ni还原用于桃小食心虫性信息素顺式碳碳双键的构建,总收率为5%。所构建的桃小食心虫性信息素合成方法操作简便,产品具有高度的区域选择性 (Z:E > 99:1),适用于桃小食心虫的绿色防控。

     

Antiplatelet and Antithrombotic Effects of Isaridin E Isolated from the Marine-Derived Fungus via Downregulating the PI3K/Akt Signaling Pathway

Isaridin E, a cyclodepsipeptide isolated from the marine-derived fungus Amphichorda felina (syn. Beauveria felina) SYSU-MS7908, has been demonstrated to possess anti-inflammatory and insecticidal activities. Here, we first found that isaridin E concentration-dependently inhibited ADP-induced platelet aggregation, activation, and secretion in vitro, but did not affect collagen- or thrombin-induced platelet aggregation. Furthermore, isaridin E dose-dependently reduced thrombosis formation in an FeCl₃-induced mouse carotid model without increasing the bleeding time. Mechanistically, isaridin E significantly decreased the ADP-mediated phosphorylation of PI3K and Akt. In conclusion, these results suggest that isaridin E exerts potent antithrombotic effects in vivo without increasing the risk of bleeding, which may be due to its important role in inhibiting ADP-induced platelet activation, secretion and aggregation via the PI3K/Akt pathways.     

模拟海底水流和光照条件下光棘球海胆行为特征及其聚礁效果的初步研究

为观察光棘球海胆Strongylocentrotus nudus在饱食、饥饿和饥饿再投喂状态下的行为特征,及其对水泥、PVC两种材质模型礁的聚集特性,在实验室中模拟光棘球海胆栖息海域底层的昼夜水流速度和光照强度进行试验。结果表明:当光照强度达到560 lx、水流速度达到20 cm/s(9:00)时,均匀分布的光棘球海胆有90%向模型礁附近区域移动;当光照强度和水流速度下降时,光棘球海胆向模型礁附近区域外移动;运动趋势明显的光棘球海胆在饱食、饥饿和饥饿再投喂3种状态下的平均移动速度分别为0.039、0.041、0.052 cm/s,3种状态下光棘球海胆顺、逆水流运动次数的比值依次为饥饿状态(1.63)饱食状态(1.18)饥饿再投喂状态(0.73),饥饿再投喂状态下光棘球海胆的活跃程度高于饱食和饥饿状态;鱼礁材质也影响光棘球海胆的聚集行为,光棘球海胆在饱食、饥饿和饥饿再投喂状态下对水泥模型礁的平均聚集率分别为25%、17%、24%,对PVC模型礁的平均聚集率分别为16%、7%、12%,光棘球海胆对两种模型礁的聚集效果均为饱食状态饥饿再投喂状态饥饿状态。研究表明,光棘球海胆在饱食和饥饿再投喂状态下对两种模型礁的聚集效果较好,而水泥材质的模型礁比PVC材质的模型礁聚集效果更好。     

桃蛀螟研究的历史、现状与展望

本文就国内外对桃蛀螟[Conogethes puncti feralis(Guene)]的研究历史与现状进行了综述,涉及桃蛀螟的生物学和生态学特性、性信息素组成、交尾行为、分类学、人工饲养及综合防治技术等方面。提出了今后有待进一步深入研究的问题。