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1.
瘤坚大球蚧蜡泌物的超微形态与红外光谱特征 总被引:3,自引:2,他引:3
采用扫描电镜和红外光谱技术研究了瘤坚大球蚧Eulecanium gigantea在不同发育阶段蜡泌物的超微形态和化学成分。结果发现:该虫在低龄期分泌湿蜡,最初在虫体背面凝结成晶体状的不同大小颗粒,接着连接成片状和块状构造,最后蜡质堆积形成龟背状蜡壳。蜡壳的各个板块与体壁上突起的腺孔分布区位置相对应。雄虫蜡壳与低龄期若虫蜡壳质地相同。雌成虫分泌的蜡质为长而卷曲的空心蜡丝。雌成虫背面和腹面蜡泌物的红外光谱特征说明二者所含的主要化学基团和成分是相同的。尽管雄虫蜡壳与雌虫的化学成分基本相似,但存在的官能团有明显差别,主要表现在雄虫蜡泌物光谱图上1736.3 cm-1处出现两个吸收峰,而雌虫只有一个;在振动频率1 242.0 cm-1~1 106.6 cm-1出现3个C-O键振动峰,而雌虫的是一系列锯齿状长碳链-C-C-C-骨架振动峰。根据红外光谱特征分析,推测该虫蜡泌物的化学成分可能主要是由长链烃、长链脂肪酸、脂肪醇和某些带芳香环的化合物组成。 相似文献
2.
朝鲜毛球蚧蜡泌物的超微形态与红外光谱特征 总被引:4,自引:3,他引:4
采用扫描电镜和红外光谱技术研究了朝鲜毛球蚧Didesmococcus koreanus在不同发育阶段蜡泌物的超微形态和化学成分。结果发现:该虫在低龄期的蜡泌物的形态是长丝状,到3龄和成虫期是由湿蜡凝结成不同大小的颗粒,块状和片状。雄虫蜡壳是薄蜡片构成,表面呈鱼鳞状凹凸。低龄期若虫蜡泌物的红外光谱特征与雌成虫的十分相似,说明二者所含的主要化学成分是相同的,雄虫和低龄若虫及雌成虫蜡壳萃取物的红外光谱的吸收峰型基本一致,但在1 240.7 cm-1处出现一个中等强度的特征峰,这充分说明3种蜡泌物的有机化合物种类和结构一致,只是雄虫分泌物与另二者比较具有特征官能团,从而,利用该吸收峰可以区别出雄虫。此外,根据红外光谱特征分析,可以知道该虫蜡泌物的化学成分主要为长链脂肪酸、脂肪醇和一些带芳香环的化合物。 相似文献
3.
为了明确寄主龄期对日本食蚧蚜小蜂Coccophagus japonicus Compere的产卵选择及后代发育的影响,本文在橡副珠蜡蚧Parasaissetia nigra Nietner 1龄若虫、2龄若虫、3龄若虫、初期成虫、褐色期成虫、初产卵期1-2 d成虫等6个发育阶段条件下观察了日本食蚧蚜小蜂的产卵选择系数、发育历期、寄生率、羽化率及性比。结果表明:选择性产卵条件下,日本食蚧蚜小蜂对褐色期成虫的产卵量、寄生率、选择系数最高,其次为初期成虫,1龄若虫最低均为0;日本食蚧蚜小蜂在橡副珠蜡蚧2龄若虫-褐色期成虫体内能完成世代发育,发育历期以褐色期寄主最长(24. 0 d),2龄若虫最短(22. 1 d);羽化率以3龄若虫最高(99. 12%),雌性比均为1。综合考虑,可选用橡副珠蜡蚧初期成虫及褐色期成虫作为日本食蚧蚜小蜂的室内扩繁寄主。 相似文献
4.
采用光学显微镜研究了枣球蜡蚧Eulecaniumgiganteum (Shinji)雄虫在不同发育期的形态特征。结果表明 :该虫雄性完成其生活史需经历初孵若虫、固定若虫、预蛹和蛹、雄成虫 4个阶段。初孵的 1龄若虫为扩散活动期 ,虫体具有发达的单眼、触角和 3对胸足 ,便于寻找寄生场所 ,但泌蜡腺体很少。 1龄后期和 2龄若虫为固定取食期 ,虫体缘毛粗大 ,泌蜡腺体很多 ,蜡泌物在虫体背面堆积成龟背状蜡壳 ,自我保护性很强。预蛹和蛹不再取食 ,虫体隐藏在白色的半透明蜡壳内。与若虫相比 ,体形变化很大 ,预蛹出现翅芽 ,而其它各器官退化 ,眼无 ,触角和足短小且分节不显。到蛹期 ,翅芽、触角和足明显长大 ,并出现感觉毛。成虫期为活动交配期 ,头部出现发达的 5对单眼 ,触角 1 0节 ,密布各种刚毛等感觉器。前翅和足发育完好。 相似文献
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云南双蜡蚧蜡泌物的超微形态与化学成分 总被引:5,自引:2,他引:5
采用扫描电镜、红外光谱、气相色谱/质谱联用技术研究了云南双蜡蚧Dicyphococcus bigibbus Borchsenius(同翅目:蚧科)蜡泌物的超微结构和化学成分。结果发现:该虫的若虫与成虫分泌的蜡质从蜡腺排出初期均为湿蜡,在体外凝结形成质地稍硬而脆的玻璃状干蜡壳,蜡壳具有均匀脊和横层。幼期和雄性蜡壳小,船形,周缘带有蜡角,中央隆起。雌成虫蜡壳大,元宝形。蜡泌物的红外光谱吸收峰密集,峰型尖锐,种的特征明显。用红外光谱特征推断蜡泌物的主要基团和化学构成在GC/MS检测中得到印证。用甲酯化和非甲酯化两种处理方法检测证明,该虫蜡泌物主要成分是一系列高级的长链饱和与不饱和的烃、脂肪酸及酯类化合物。化合物的碳原子数从C14~C40,大部分为偶数个,特别是碳链长度在C30~C40的酯类化合物种类多,比例大。还将该蚧虫蜡泌物的特征与蚧科内近缘的蜡蚧属种类及瘤坚大球蚧、朝鲜毛球蚧、背刺毡蜡蚧、白蜡虫等作了对比,阐述了蜡泌物在蚧虫分类、系统学及防治中的意义。 相似文献
7.
【目的】梧桐木虱Carsidara limbata是一种严重危害梧桐Firmiana simplex的害虫,观察并明确若虫蜡泌物及不同虫龄泌蜡腺体超微形态特征,有助于为其生长发育的相关研究提供理论依据。【方法】本研究依据梧桐木虱若虫形态特征变化划分样本虫龄,使用体视显微镜和扫描电镜(SEM)观察若虫蜡泌物及不同虫龄泌蜡腺体的超微形态结构特征。【结果】结果表明,梧桐木虱若虫泌蜡腺体主要分为两类:一类为泌蜡小孔,3-5龄若虫体壁出现此结构;另一类为规则或不规则圆形多孔蜡腺孔,该结构1龄若虫极少或无,其他虫龄均有分布。低龄若虫孔腺数目和类型较老龄少。若虫蜡泌物分为4种类型,即丝状蜡丝、空心"C"形蜡丝、弹簧状蜡丝、空心长蜡丝。此外,腹部末端有环肛孔环结构,腹部背腹面遍布微刺及各类刚毛。【结论】梧桐木虱若虫有4类蜡泌物和2类泌蜡腺体,随虫龄不同其类型和分布存在差异。本研究为裂木虱科害虫泌蜡器官的研究提供了参考依据。 相似文献
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角蜡蚧和日本龟蜡蚧蜡泌物的超微结构及化学成分分析 总被引:1,自引:0,他引:1
采用扫描电镜和气相色谱/质谱联用技术研究了角蜡Ceroplastes ceriferus (Fabricius) 和日本龟蜡蚧C. japonicus Green蜡泌物的超微结构及化学成分。结果表明,这2种蜡蚧分泌蜡质和形成蜡壳的过程基本相似。在1、2龄期分泌的蜡质为“干蜡”,蜡壳为星芒状,虫体周缘的蜡芒均为2大节,与其2个龄期发育相对应,每一个大节又分为若干小节。同时,虫体背面中央蜡质堆积成帽状,也分为均匀的多层。由此说明泌蜡过程具有节律性。虫体周缘与蜡芒对应的突起区上分布着密集的刻点状腺孔,每一个腺孔分泌1根蜡丝,这在以往玻片标本中是观察不到的。雌性第3龄幼虫和成虫期,虫体分泌“湿蜡”,形成龟背状蜡壳,泌蜡腺孔主要为三格腺和四格腺。在肛突区发现了密集的泌蜡腺孔,排列为纵条纹状。从角蜡蚧蜡泌物甲酯化处理样品中检测到14个组分,从直接测试 (未经甲酯化处理) 样品中检测到14个组分;而从日本龟蜡蚧则分别检测到10个组分和25个组分。它们的主要成分是一系列高级的长链饱和与不饱和的烃、脂肪酸、脂肪醇、酯类、醛类以及杂环、多环或大环状化合物。对它们可能的生物生态学功能进行了讨论。 相似文献
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扶桑绵粉蚧生物学特性研究 总被引:17,自引:2,他引:15
扶桑绵粉蚧Phenacoccus solenopsis Tinsley是近年在我国新发现的一种重要外来入侵害虫, 特别是对我国棉花生产具有潜在的巨大威胁,本文研究了实验室条件下(27±1℃, RH 70%±5%)该虫在棉花上的发育历期、 繁殖能力及各虫态的形态特征。结果表明:扶桑绵粉蚧雌虫生活史包括卵、1龄若虫、2龄若虫、3龄若虫和雌成虫;雄虫生活史包括卵、1龄若虫、 2龄若虫、预蛹、 蛹和雄成虫。卵期很短,雌虫若虫期15~20 d,总历期约为47~59 d;雄虫若虫和蛹期17~22 d,总历期约为20~26 d;雌虫寿命明显长于雄虫。该蚧虫繁殖能力强,雌成虫产卵量200~862粒/头,平均产卵458粒/头。各虫态主要形态特征为:卵呈长椭圆形,橙黄色, 略微透明; 1龄若虫,淡黄绿色,行动活泼;2龄若虫体缘突起显现, 尾瓣突出,至末期可根据体表黑斑的可见程度区分雌、 雄虫;3龄雌若虫, 体表有薄层蜡粉, 在前、中胸背面亚中区和腹部1~4节背面亚中区可见清晰斑点, 形成纵向黑色条斑, 外表形似雌成虫。雌成虫呈卵圆形,体表蜡粉厚实,胸、腹背面的黑色条斑在蜡粉覆盖下呈成对黑色斑点状,体缘蜡突明显,共18对,其中腹部末端2~3对较长; 雄虫蛹包裹于松软的白色丝茧中;雄成虫,虫体较小,黑褐色;触角细长,具一对发达透明前翅,后翅退化为平衡棒,腹部末端具2对白色长蜡丝。本文通过对扶桑绵粉蚧的基本生物学特性和各个龄期发育的形态特征的研究, 为该虫的进一步研究和科学防控提供了基本资料,具有重要的理论和实践意义。 相似文献
11.
Nazarova AF Alkhutov SM 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》2008,66(1):51-66
The electrophoretical polymorphisms of some blood proteins were studied in the Talysh population of Pirasora situated in South-East Azerbaidjan. We calculated the gene frequencies of these polymorphisms and determined the genetic distances between the Talyshes and some Iranian populations of North, Central and South Iran, Afghans, and three populations of Azerbaijan. The Talyshes are very close to Iranians of Shiraz, whereas they are distant from the Azerbaijanians. Anthropological investigations showed that the Caucasoids and Mongoloids lived in the Aragvi Basin since the Eneolithic period. This was stated by Alexeev (1974), who emphasized the mixture of the Caucasus populations from ancient times on. We calculated the genetic distances between the Caucasus populations and numerous populations of other geographic regions, considering 28 alleles of 12 loci of blood group, serum protein and red cell enzyme polymorphisms and constructed the dendrogram of these populations. The position of the Caucasus populations in the dendrogram corresponds on principle to the earlier anthropological observations. The clustering of the Caucasoid populations corresponds completely with anthropological and historical data, and supports our earlier hypothesis (Nazarova 1999) concerning the differentiation of Caucasoids, Northern Mongoloids and Amerinds from the populations, which inhabitated Asia in palaeolithic times. 相似文献
12.
Several different models of the linker histone (LH)–nucleosome complex have been proposed, but none of them has unambiguously revealed the position and binding sites of the LH on the nucleosome. Using Brownian dynamics-based docking together with normal mode analysis of the nucleosome to account for the flexibility of two flanking 10 bp long linker DNAs (L-DNA), we identified binding modes of the H5-LH globular domain (GH5) to the nucleosome. For a wide range of nucleosomal conformations with the L-DNA ends less than 65 Å apart, one dominant binding mode was identified for GH5 and found to be consistent with fluorescence recovery after photobleaching (FRAP) experiments. GH5 binds asymmetrically with respect to the nucleosomal dyad axis, fitting between the nucleosomal DNA and one of the L-DNAs. For greater distances between L-DNA ends, docking of GH5 to the L-DNA that is more restrained and less open becomes favored. These results suggest a selection mechanism by which GH5 preferentially binds one of the L-DNAs and thereby affects DNA dynamics and accessibility and contributes to formation of a particular chromatin fiber structure. The two binding modes identified would, respectively, favor a tight zigzag chromatin structure or a loose solenoid chromatin fiber. 相似文献
13.
F K Fuss 《Gegenbaurs morphologisches Jahrbuch》1990,136(1):37-68
In order to analyze the complicated movements of the mandible as the open-closing movement and the protrusio are, it is useful to evaluate the basic kinematic principles and reduce them to simple technical constructions. Both the open-closing movement and the protrusio could be reduced to 4-bar links, which were used to simulate the movements with help of a computer. Besides, the polodes and the curves of points in the muscular attachments could be constructed. The 2 entirely different 4-bar links have 3 things in common: The resting system - cranium, the moving system - mandibula, and 1 of the 2 arms connecting these 2 systems - the ligamentum laterale. As this ligament is taut during movements it can be considered a "guiding ligament" representing 1 of the 3 determining components of the mandibular movements. The other of the 2 arms has no anatomical equivalent; this arm, however, is "replaced" by the 2 other determining components of the mandibular movements: the joint and the muscles. The curves, which the Caput mandibulae describes, are practically identical for the open-closing movement and the protrusio despite of the different 4-bar links and these curves exactly correspond to the Discus articularis, taut by the upper part of the M. pterygoideus lateralis. The muscles do not only just move the mandibula, but they are also the component, which can choose between the different mandibular movements. By means of the curves, which points in the muscular attachments describe, the function of the masticatory muscles could be analyzed exactly. 相似文献
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The systematic position ofthe Ebenaceae, Sapotaceae, Styracaceae, Ochnaceae, Stachyuraceae, Dipterocarpaceae, Clusiaceae and Hypericaceae has been investigated using serological comparisons of sets of antigenic determinants. The results show that the Sytracaceae and Sapotaceae are undoubtedly more closely associated with the Actinidiaeceae and Theaceae, respectively, than with each other. We found no corresponding determinants betnween antigen systems from the Ebenaceae and systems from any other family whose relations to this family have been proposed. As discovered previously, investigations of antigen systems from the Ochnaceae, Dipterocarpaceae, Stachyuraceae, Clusiaceae and Hypericaceae are against the idea of a natural order “Theales” in which these families, or at least some of them, are combined with the Theaceae and Actinidiaceae. This paper completes our previous investigations which largely support a superorder Ericanae sensu Ehrendorfer and Takhtajan. We propose to include the Actinidiaceae and Theaceae in this superorder, assigning them a central position laong with the Sapotaceae and Sytracaeae on one side and the Primulales and Ericales on the other. Another most interesting finding is that there are corresponding determinants between antigen systems from the members of the Ericanae and representatives of the Polemoniaceae and Loasaceae. 相似文献
16.
Interpreting channel behavior in patches requires an understanding of patch structure and dynamics, especially in studies of mechanosensitive channels. High resolution optical studies show that patch formation occurs via blebbing that disrupts normal membrane structure and redistributes in situ components including ion channels. There is a 1-2 μm region of the seal below the patch where proteins are excluded and this may consist of extracted lipids that form the gigaseal. Patch domes often have complex geometries with inhomogeneous stresses due to the membrane-glass adhesion energy (Ea), cytoskeletal forces, and possible lipid subdomains. The resting tension in the patch dome ranges from 1-4 mN/m, a significant fraction of the lytic tension of a bilayer (∼10 mN/m). Thus, all patch experiments are conducted under substantial, and uneven, resting tension that may alter the kinetics of many channels. Ea seems dominated by van der Waals attraction overlaid with a normally repulsive Coulombic force. High ionic strength pipette saline increased Ea and, surprisingly, increased cytoskeletal rigidity in cell-attached patches. Low pH pipette saline also increased Ea and reduced the seal selectivity for cations, presumably by neutralizing the membrane surface charge. The seal is a negatively charged, cation selective, space with a resistance of ∼7 gigohm/μm in 100 mM KCl, and the high resistivity of the space may result from the presence of high viscosity glycoproteins. Patches creep up the pipette over time with voltage independent and voltage dependent components. Voltage-independent creep is expected from the capillary attraction of Ea and the flow of fresh lipids from the cell. Voltage-dependent creep seems to arise from electroosmosis in the seal. Neutralization of negative charges on the seal membrane with low pH decreased the creep rate and reversed the direction of creep at positive pipette potentials. 相似文献
17.
人类基因组及后基因组研究进展及其应用与开发研究现状 总被引:9,自引:0,他引:9
人类对自身基因组的研究,随着人类基因组工作草图的绘制完成和对基因功能研究的深入已加快进入了实质性、关键性的开发利用阶段。本文概述了人类基因组及后基因组的研究进展及依此开展基因治疗及基因(组)药物研制等应用开发研究的现状。 相似文献
18.
Yasushi Toge Yukihide Nishimura Jeffrey R. Basford Takako Nogawa Midori Yamanaka Takeshi Nakamura Munehito Yoshida Akira Nagano Fumihiro Tajima 《PloS one》2013,8(12)
Objective
To assess the separate effects of thumb and finger extension/flexion on median nerve position and cross-sectional area.Methods
Ultrasonography was used to assess median nerve transverse position and cross-sectional area within the carpal tunnel at rest and its movement during volitional flexion of the individual digits of the hand. Both wrists of 165 normal subjects (11 men, 4 women, mean age, 28.6, range, 22 to 38) were studied.Results
Thumb flexion resulted in transverse movement of the median nerve in radial direction (1.2±0.6 mm), whereas flexion of the fingers produced transverse movement in ulnar direction, which was most pronounced during flexion of the index and middle fingers (3.2±0.9 and 3.1±1.0 mm, respectively). Lesser but still statistically significant movements were noted with flexion of the ring finger (2.0±0.8 mm) and little finger (1.2±0.5 mm). Flexion of the thumb or individual fingers did not change median nerve cross-sectional area (8.5±1.1 mm2).Conclusions
Volitional flexion of the thumb and individual fingers, particularly the index and middle fingers, produced significant transverse movement of the median nerve within the carpal tunnel but did not alter the cross-sectional area of the nerve. The importance of these findings on the understanding of the pathogenesis of the carpal tunnel syndrome and its treatment remains to be investigated. 相似文献19.
Lars Orrhage 《Acta zoologica》1996,77(2):137-151
Abstract Earlier papers dealing with the anatomy of the hesionids and syllids were studied. Thereby it was found that information about the structure of the central nervous system was meagre. As a result, the anterior end appendages, especially the large, laterloventral ones of the Syllidae, have been differently interpreted. This prompted a re-investigation. The circum-oesophageal connectives, the brain commissures and the innervation of the alimentary canal and the cephalic appendages of a number of hesionid and syllid species were studied. The results, summarized in schematic diagrams, were compared with corresponding observations in other polychaete families. Among other things, it was concluded that not only the latero-ventral cephalic appendages of the hesionids but also those of the syllids are homologous with the palps of the nereids and of many other “errant” and “sedentary” families. 相似文献