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1.
昆虫作为防治疾病的药物,在我国已有2 000多年的历史。随着我国中医药事业的发展,药用昆虫的应用愈来愈广泛。近年的研究表明,药用昆虫具有更广泛的药理活性,在抗恶性肿瘤、免疫调节、神经性疾病、心脑血管疾病等具有独特的疗效。本研究主要综述近年来有关药用昆虫药理活性的最新研究进展,为有效利用药用昆虫资源、发掘药用昆虫新临床适应症,继承和发扬我国医药遗产提供参考。  相似文献   

2.
《武夷科学》2020,(1):1-15
植食性昆虫和植物均能与微生物形成密切关系,它们各自的生态功能及相互关系也常被共生微生物所影响。近年来,随着分子水平研究方法的进展,植食性昆虫和植物中很多可遗传共生微生物(细菌、真菌等)被发现。共生微生物能够在营养、生殖、防御和解毒等方面给宿主带来显著影响,并与宿主形成竞争、互利或寄生等关系。植食性昆虫体内的含菌胞、肠道、血淋巴、唾液腺等常含有重要功能的共生微生物。新的分子生物学手段和高通量测序技术的应用使得我们能够增加对宿主和共生微生物(即使处于低丰度)之间关系的了解。本文尝试总结了植食性昆虫和植物共生微生物的多样性及其关系、昆虫和植物互作机制、昆虫共生菌解毒植物毒素等方面的近期证据,突出强调了应以系统观思维来理解共生微生物、植食性昆虫和植物间的功能关联,并就将来值得研究的问题提出了建议。  相似文献   

3.
微孢予虫可以侵染大多数的昆虫,包括经济昆虫和农业害虫,并对其造成一定程度甚至是毁灭性的影响.了解微孢子虫在本地区的分布对于农作物害虫的防治和经济昆虫的防疫具有重要意义.本文介绍了黄瓜山地区微孢子虫在昆虫中的分布调查情况,对害虫防治和经济昆虫微孢子虫病的防疫提供了一定的参考和依据.  相似文献   

4.
Insects breathe discontinuously to avoid oxygen toxicity   总被引:1,自引:0,他引:1  
Hetz SK  Bradley TJ 《Nature》2005,433(7025):516-519
The respiratory organs of terrestrial insects consist of tracheal tubes with external spiracular valves that control gas exchange. Despite their relatively high metabolic rate, many insects have highly discontinuous patterns of gas exchange, including long periods when the spiracles are fully closed. Two explanations have previously been put forward to explain this behaviour: first, that this pattern serves to reduce respiratory water loss, and second, that the pattern may have initially evolved in underground insects as a way of dealing with hypoxic or hypercapnic conditions. Here we propose a third possible explanation based on the idea that oxygen is necessary for oxidative metabolism but also acts as a toxic chemical that can cause oxidative damage of tissues even at relatively low concentrations. At physiologically normal partial pressures of CO2, the rate of CO2 diffusion out of the insect respiratory system is slower than the rate of O2 entry; this leads to a build-up of intratracheal CO2. The spiracles must therefore be opened at intervals to rid the insect of accumulated CO2, a process that exposes the tissues to dangerously high levels of O2. We suggest that the cyclical pattern of open and closed spiracles observed in resting insects is a necessary consequence of the need to rid the respiratory system of accumulated CO2, followed by the need to reduce oxygen toxicity.  相似文献   

5.
 2016年国际古生物研究领域见证了一系列重要事件和研究热点。本文回顾2016年在地球早期生命研究、琥珀中的特异保存化石、中生代羽毛的颜色的分子证据、志留纪古鱼、早泥盆世植物根系、古DNA等研究方向的重要进展,盘点了国际古生物研究领域的前沿及热点,部分展示了中国古生物学界做出的突出贡献。  相似文献   

6.
Frontal and stealth attack strategies in microbial pathogenesis   总被引:2,自引:0,他引:2  
Merrell DS  Falkow S 《Nature》2004,430(6996):250-256
Interactions between microbes and human hosts can range from a benign, even symbiotic collaboration to a competition that may turn fatal--resulting in death of the host, the microbe or both. Despite advances that have been made over the past decades in understanding microbial pathogens, more people worldwide still die every year from infectious disease than from any other cause. This highlights the relevance of continuing to probe the mechanisms used by microorganisms to cause disease, and emphasizes the need for new model systems to advance our understanding of host-pathogen interactions.  相似文献   

7.
利用~(60)CO~—r射线辐照毛皮杀虫试验表明,昆虫种类和虫态不同,对不同剂量和剂量率的辐照敏感性不同。以杀虫为目的,短期内造成死亡的致死剂量,白腹皮蠹以1.0—1.2KGY、黑皮蠹以1.2—1.4KGY较为适宜。在适宜的致死剂量范围内,革和裘的理化性能符合部定指标。  相似文献   

8.
真菌与昆虫是自然界存在的两个最大生物类群.两者在漫长的进化过程中逐渐形成了复杂而密切关系,无论在昆虫的体表还是昆虫的体内,都存在着丰富的真菌类群.许多昆虫都与真菌间形成了互惠的共生关系,因而才得以更好的利用资源、适应环境和占领新的生境.研究真菌和昆虫的互作和协同进化对于我们认识生物多样性的形成、物种的分化、生物地理分布等有着重要意义.  相似文献   

9.
延安地区药用昆虫资源研究   总被引:2,自引:0,他引:2  
通过1992--2003年野外调查和结合文献资料,对延安地区药用昆虫的种类、分布进行了研究。结果表明:延安地区药用昆虫53种,分属10目32科,分别占全国和陕西省主要药用昆虫总数的31.18%和92.98%,并对其开发利用的现状提出了建议。  相似文献   

10.
 植物与昆虫是当今陆地生态系统的重要组成部分,两者之间的相互关系为认识陆地生态系统结构和功能提供独一无二的信息。古生代是植物和昆虫起源和早期演化的关键地质时期,然而由于缺乏对该时期化石材料的系统研究,植物和昆虫之间的相互关系及其协同演化过程还存在许多未解之谜。对二叠纪晚期(约2.53亿年前)植物茎干中甲虫蛀孔的详细解剖学研究,证实当时蛀木甲虫利用真菌实现个体发育过程中食性的转变,而且蛀木甲虫可能存在初步的社会分工,并生活在复杂的生态网络中;进一步研究显示晚二叠世蛀木甲虫或对松柏类植物引起严重的虫灾。当前研究表明,渗矿化植物化石标本在探索地质历史时期动植物相互作用方面具有巨大研究潜力,可为深时陆地生态系统的重建和演化提供宝贵信息。  相似文献   

11.
本文把《中国数学文摘》采用的分类表,以任意三个例子为例同《中国图书资料分类法》作了详细比较,提出《中国图书资料分类法》不适用于数学科学文献的分类,分析了不适用的原因,并对《中国图书资料分类法》日后的修改提出一些建议.  相似文献   

12.
图书馆精神与高校图书馆事业   总被引:1,自引:0,他引:1  
围绕图书馆精神与高校图书馆事业这一主题,介绍了图书馆精神的内涵与作用,提出了以图书馆精神促进高校图书馆事业发展的途径。  相似文献   

13.
Rappuoli R  Aderem A 《Nature》2011,473(7348):463-469
Acquired immune deficiency syndrome (AIDS), malaria and tuberculosis collectively cause more than five million deaths per year, but have nonetheless eluded conventional vaccine development; for this reason they represent one of the major global public health challenges as we enter the second decade of the twenty-first century. Recent trials have provided evidence that it is possible to develop vaccines that can prevent infection by human immunodeficiency virus (HIV) and malaria. Furthermore, advances in vaccinology, including novel adjuvants, prime-boost regimes and strategies for intracellular antigen presentation, have led to progress in developing a vaccine against tuberculosis. Here we discuss these advances and suggest that new tools such as systems biology and structure-based antigen design will lead to a deeper understanding of mechanisms of protection which, in turn, will lead to rational vaccine development. We also argue that new and innovative approaches to clinical trials will accelerate the availability of these vaccines.  相似文献   

14.
This study used the sequence of the mitochondrial Cytochrome b(Cytb)to estimate phylogenetic relationships among host Hepialidae insects of Cordyceps sinensis.Genome DNA of host insect was extracted from the dead larva head part of 18 cordyceps populations and 2 species of Hepialus,and the Cytb fragment of host insect was amplified with PCR technique.The nucleotide sequence alignments and their homologous sequences of 24 species host Hepialidae insects of Cordyceps sinensis were obtained from GenBank and were used to construct phylogenetic trees based on neighbor-joining method.The results showed that genus Bipectilus diverged earlier than genus Hepialus and Hepialiscus.Hepialus host insects of Cordyceps sinensis have multitudinous species with different morphological characteristics and geographical distributions.The interspecific genetic differentiations are obvious in Hepialus.Thus,the genus Hepialus might be considered as polyphyletic origin.Cytb sequences have abundant variations among the host insects of Cordyceps sinensis on spe- cific and generic level.The divergence rate of Cytb sequences among the species in Hepialus ranged from 0.23% to 9.24%,except that Hepialus pratensis and Hepialus jinshaensis have the same sequence.Cytb sequence can be used for species identification of host insects of Cordyceps sinensis,but further confirmation in more host insect species is needed.To obtain the Cytb sequence of host insect by ampli- fying DNA extracted from the head part of dead larva in cordyceps turns out to be an effective and accurate approach,which will be useful for studies on phylogeny and genetic structure of host insects of cordyceps populations,especially for analyzing relationships between C. sinensis and its host insects.  相似文献   

15.
This study used the sequence of the mitochondrial Cytochrome b (Cytb) to estimate phylogenetic relationships among host Hepialidae insects of Cordyceps sinensis. Genome DNA of host insect was extracted from the dead larva head part of 18 cordyceps populations and 2 species of Hepialus, and the Cytb fragment of host insect was amplified with PCR technique. The nucleotide sequence alignments and their homologous sequences of 24 species host Hepialidae insects of Cordyceps sinensis were obtained from GenBank and were used to construct phylogenetic trees based on neighbor-joining method. The results showed that genus Bipectilus diverged earlier than genus Hepialus and Hepialiscus. Hepialus host insects of Cordyceps sinensis have multitudinous species with different morphological characteristics and geographical distributions. The interspecific genetic differentiations are obvious in Hepialus. Thus, the genus Hepialus might be considered as polyphyletic origin. Cytb sequences have abundant variations among the host insects of Cordyceps sinensis on specific and generic level. The divergence rate of Cytb sequences among the species in Hepialus ranged from 0.23% to 9.24%, except that Hepialus pratensis and Hepialus jinshaensis have the same sequence. Cytb sequence can be used for species identification of host insects of Cordyceps sinensis, but further confirmation in more host insect species is needed. To obtain the Cytb sequence of host insect by amplifying DNA extracted from the head part of dead larva in cordyceps turns out to be an effective and accurate approach, which will be useful for studies on phylogeny and genetic structure of host insects of cordyceps populations, especially for analyzing relationships between C. sinensis and its host insects.  相似文献   

16.
SO4 2 -/MxOy 型固体超强酸作为酯化反应的催化剂 ,具有催化活性高 ,选择性好 ,易与产品分离 ,无污染 ,可重复利用等优点。本文综述了SO4 2 -/MxOy 型固体超强酸的研究进展及其在酯化反应中的催化作用 ,探讨了这类固体超强酸的制备条件、表面结构及其用作酯化催化剂的性能。  相似文献   

17.
 白垩纪缅甸琥珀中内含物研究是当前古生物研究的热点之一。隐翅虫形态多样、分布广泛、种类繁多,目前是动物界最大的一个科。近些年,在缅甸琥珀中发现了种类丰富多样的隐翅虫化石,为研究陆地生态系统中的生物多样性的演化提供了重要材料。通过对保存精美的隐翅虫化石的研究,不仅可以揭示隐翅虫科昆虫的起源和演化,而且有助于认识早期陆地生态系统中昆虫与真菌以及昆虫之间的复杂关系,揭示高等真菌和社会性昆虫的早期演化历史。先进的成像技术和分析方法可以帮助人们深入认识缅甸琥珀昆虫的形态功能,理解远古昆虫与周围环境的复杂关系,进而重建远古陆地森林生态系统的整体面貌。  相似文献   

18.
The search for new cardiovascular biomarkers   总被引:1,自引:0,他引:1  
Gerszten RE  Wang TJ 《Nature》2008,451(7181):949-952
Despite considerable advances in the treatment of cardiovascular disease, it remains the leading cause of death in developed countries. Assessment of classic cardiovascular risk factors--including high blood pressure, diabetes and smoking--has a central role in disease prevention. However, many individuals with coronary heart disease (a narrowing of the blood vessels that supply the heart) have only one, or none, of the classic risk factors. Thus, new biomarkers are needed to augment the information obtained from traditional indicators and to illuminate disease mechanisms.  相似文献   

19.
 昆虫产卵过程对寄主植物的直接刺激包括产卵器的机械损伤和卵表面物质带来影响,这些刺激是启动植物诱导抗虫性的重要途径。通过对褐飞虱产卵处理后水稻植株内胰蛋白酶抑制剂(BBPI)合成酶基因的表达量及物质含量的测定,对比褐飞虱取食和机械损伤处理,发现褐飞虱产卵能够诱导水稻BBPI合成酶基因的表达和BBPI物质的生成。处理后6 h,12 h,水稻 BBPI 表达量显著高于取食和机械损伤处理;产卵诱导的BBPI物质含量显著高于正常水稻。褐飞虱产卵诱导水稻启动〖WTBX〗BBPI〖WTBZ〗表达和物质合成表明,与取食危害类似,水稻同样会对褐飞虱产卵刺激产生响应,启动相应的植物防御体系,进而达到阻滞褐飞虱危害的目的。  相似文献   

20.
<正>海南省尖峰岭热带林自然保护区昆虫的垂直分布明显,昆虫区系属东洋界,其中许多种类是热带区域或热带山地雨林的特有种,这些昆虫具有区系稳定、种类多而种群数量少、鳞翅目丰富、广腰亚目贫乏等特色;受季风和生物同步现象的影响,森林昆虫每年都有二个发生高峰。热带森林害虫的防治,应在生态学原理的指导下,保护好现有的原始林,对已破坏了的原始林地区,需用封山育林、营造混交林等林业措施来改善森林结构,建立起新的生态平衡,从而对害虫达到自然控制的目的。  相似文献   

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