君子兰化学成分和药理研究进展

君子兰为名贵的观赏性植物,具有广泛的生理及药理活性。君子兰中含有生物碱类、苷类、黄酮类、氨基酸类和无机元素类等多种化学成分。本文综述了君子兰中的化学成分及其在中枢神经系统、心血管系统、抗菌、抗炎、抗病毒和抗肿瘤等方面的药理作用。     

天然药物—皂苷的主要生物活性及分离纯化方法

皂苷类化合物是一大类具有多种生理功能的生物活性物质,包括抗炎、抗肿瘤、抗动脉粥样硬化、免疫调节等方面的药理作用,皂苷类的初提物通常存在有效成分含量低、杂质多、质量不稳定等缺点,在此查阅了国内外相关资料,对皂苷类化合物的主要生物活性和纯化方法进行了归纳总结,并对各方法的优缺点进行了比较,为皂苷类化合物的进一步研究提供了参考.     

黄芪多糖的药理作用及其在仔猪疾病防治中应用的研究进展

黄芪是一味药食两用、补中益气的中国传统中药,黄芪多糖是其最重要的天然活性成分,具有无耐药性、抗菌、抗病毒、提高机体免疫力及抗氧化功能,改善肠道微生态等作用,其中以免疫调节作用最为突出。大量研究证明,黄芪多糖在体内外均具有显著的免疫调节作用。作者归纳了黄芪多糖对免疫相关基因的调控,在器官免疫、细胞免疫、细胞因子和胞内信使物质、心血管系统免疫、抗菌免疫、抗病毒免疫等方面的作用,以及其作为免疫佐剂在猪瘟（CSF）、猪圆环病毒病（PCVD）、猪口蹄疫（FMD）、猪繁殖与呼吸综合征（PRRS）、猪支原体肺炎（MPS）等仔猪疾病应用的最新研究进展,发现黄芪多糖主要作为免疫佐剂及动物饲料添加剂使用,应用范围狭窄,缺乏深度的研究开发。今后应加强对分离、纯化后的均一组分低分子质量黄芪多糖及其结构特点,以及其与免疫调节作用间构效关系的研究以提高黄芪多糖疗效,推广其临床应用。     

华南虎哺乳期母幼行为的初步研究

对梅花山华南虎繁育研究所内 4号母虎及其所产幼虎的母幼行为进行了初步研究 ,着重描述了华南虎母幼的各种行为 ,并对其中的一些行为作了初步探讨。母幼间接触的部位主要是头部等感官较敏感区域 ,通过各种接触是建立母幼友好、亲昵关系的主要途径。母虎主要通过哺乳、舔、嗅等行为与幼虎接触 ,其次是拱、衔、护幼行为等 ;而幼虎主要是通过吮乳、舔、嗅闻与母虎接触 ,其次是叫等方式     

Fire management for biodiversity conservation: Key research questions and our capacity to answer them

Knowing how species respond to fire regimes is essential for ecologically sustainable management. This axiom raises two important questions: (1) what knowledge is the most important to develop and (2) to what extent can current research methods deliver that knowledge? We identify three areas of required knowledge: (i) a mechanistic understanding of species’ responses to fire regimes; (ii) knowledge of how the spatial and temporal arrangement of fires influences the biota; and (iii) an understanding of interactions of fire regimes with other processes. We review the capacity of empirical research to address these knowledge gaps, and reveal many limitations. Manipulative experiments are limited by the number and scope of treatments that can be applied, natural experiments are limited by treatment availability and confounding factors, and longitudinal studies are difficult to maintain, particularly due to unplanned disturbance events. Simulation modelling is limited by the quality of the underlying empirical data and by uncertainty in how well model structure represents reality. Due to the constraints on large-scale, long-term research, the potential for management experiments to inform adaptive management is limited. Rather than simply recommending adaptive management, we define a research agenda to maximise the rate of learning in this difficult field. This includes measuring responses at a species level, building capacity to implement natural experiments, undertaking simulation modelling, and judicious application of experimental approaches. Developing ecologically sustainable fire management practices will require sustained research effort and a sophisticated research agenda based on carefully targeting appropriate methods to address critical management questions.     

小流域人类活动的时空分异的景观格局特征——以纸坊沟流域为例

纸坊沟流域位于黄土高原典型的丘陵沟壑区,是黄土高原小流域综合治理的示范区。从上世纪30年代以来,纸坊沟流域经历了从急剧破坏到缓慢恢复、基本保持和快速恢复的四个阶段,其中每一个阶段的人类活动都有其鲜明的特色。为了量化人类活动的程度和人类活动对土壤侵蚀的影响,本文将纸坊沟流域的土地利用类型归并为两类:加剧侵蚀的斑块和减缓侵蚀的斑块,并根据流域的海拔高度,给流域内每个土地利用斑块分别赋予位置属性。然后根据人类活动与土壤侵蚀的关系提取了5个景观格局指标,分别计算各指标自上世纪30年代以来的变化情况,并划分变化阶段,分析各阶段的景观格局变化情况后,本文得出以下结论:1)人类活动变化最剧烈最频繁的区域在坡下(即流域内海拔高度介于1100—1150m之间的区域);2)流域破坏性开发体现在斑块破碎化,而流域治理体现在斑块连通度增加;3)在流域治理过程中,流域景观格局变化特征体现在:减缓侵蚀的斑块被合并,加剧侵蚀的斑块部分被合并,部分被转化为减缓侵蚀的斑块。     

农业活动对农田生态系统物种多样性的影响

农业活动如化肥、农药、地膜的使用、高产品种的推广、节水灌溉技术的应用等,所导致的生境条件的变化和农田景观结构的不合理是影响农田生态系统物种多样性的重要原因。鉴于此,提出了保护农田生态系统物种多样性的几点建议：①建立可持续的生态农业;②进行合理的农田生态规划;③合理的混合种植不同作物,打破单一的种植结构。     

Gillnet fishing drives lake‐migrating brown trout to near extinction in the Lake Päijänne region,Finland

Abstract Wild stocks of brown trout, Salmo trutta L., collapsed in Finnish inland waters during the 20th Century because dams prevented upstream migration, and low water quality and stream dredging weakened reproduction. The demise in migratory stocks was coupled with overfishing, mainly by gillnetting on lakes. Consequently, the migratory spawning stocks have diminished to negligible levels. The remaining stocks exhibit restricted immigration and emigration, are supplemented by continuous stocking, and their natural genetic diversity is affected by human activities. In recent years, various recovery actions have been implemented including stream channel restorations, fish passage facilities constructed and stocking of eggs and smolts. Gillnetting has also been regulated by banning certain mesh sizes, and catch‐and‐release of wild trout is spreading amongst sport fishers. However, these measures seem to be inadequate and almost no recovery of migratory populations has been reported. The problem of by‐catch in intensive gillnetting continues to threaten stocks and creates disputes between stakeholders.     

儿童早期发展与教育中最重要的内容：动作教育与综合训练

运用文献资料研究、比较、思辨等方法对动作教育在儿童早期发展与教育中的意义、儿童早期动作教育的概念与内容、当前我国幼儿园动作教育现状与困境进行了阐述;指出：儿童动作学习核心经验的研究是中国早期教育中最薄弱的环节,并对进行幼儿动作教育与综合训练学习时应注意的事项等国内外热点问题进行了探讨分析,旨在为落实教育部于2012年9月颁布的《3~6岁儿童学习与发展指南》、促进幼儿的动作教育与综合身体训练的常规化、正规化提供参考依据。