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31.
Abstract  All ants (Hymenoptera, Formicidae) are highly eusocial insects that are characterized by reproductive division of labor with sterile castes (worker and soldier) helping fertile castes (queen and male) to reproduce.
Ant societies, like other complex animal societies, have developed a sophisticated communication system, in which recognition behaviors are frequently involved Recognition abilities allow individuals to orient and modulate their behaviors effectively and appropriately in response to the characteristics andlor signals expressed by other organisms. Among recognition behaviors, nestmate recognition and kin recognition mechanisms have attracted great attention of sociobiologists, ecologists, insect physiologists and biochemists since 1970's. This is parallel with the popularization of Hamilton's kin selection theory. The present paper aims at reviewing the current understanding on nestmate/kin recognition in ants. This review consists of three parts. The first part concerns the diversity of recognition behaviors and their ecological implications with emphasis on nestmatelkin recognition; in the second part, the current understandings on the mechanism of nestmatelkin recognition are outlined; and in the third part, we discuss the ontogenetic development of nestmate recognition behavior and naturally mixed colonies. The study of the integration mechanism of social parasite may provide heuristic clues to the understanding of kin/nestmate recognition system.  相似文献   
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33.
The chemical reaction of cleavaging territrem B to give 3,4,5-trimethoxy benzoic acid by alkaline hydrogen peroxide was investigated. The method was applied for confirmation of the chemical structure of the aromatic moiety of territrem A, A’, B, and B’. The physicochemical properties of the aromatic cleavage product of territrem Aindicated the structure as 3,4-methylendioxy, 5-methoxy benzoic acid (or 4-methoxy, 6-carboxy, 1, 3-benzodioxole). The experiment also gave the evidences that territrem A and A’, on the other hand territrem B and B’ have the identical aromatic moieties on their structures.  相似文献   
34.
The ciliate protozoan Paramecium tetraurelia produces secretory granules (trichocysts) which release needle-like structures composed of small, acidic proteins. Using antibodies against isolated chromogranin A (CGA) and against trichocyst proteins, we found cross-reactive proteins in chromaffin granules and trichocysts. Four independently derived sera against isolated CGA stained bands of the Mr 15,000-25,000 family of trichocyst proteins on immunoblots. A positive response was also obtained with antiserum against chemically synthesized peptides (PL26 and GE25) corresponding to defined regions of the CGA amino acid sequence. In extracts of whole Paramecium, larger proteins (Mr 53,000 and 49,000) also reacted with antibodies against CGA and the related synthetic peptides. These larger proteins may represent unprocessed precursors to the smaller proteins of mature trichocysts. Antiserum to trichocysts recognized CGA in chromaffin granule lysates. Further evidence of a Paramecium protein related to CGA was provided by hybridization of Paramecium mRNA with cloned cDNA for bovine CGA. Our results suggest striking conservation in evolution of CGA-like proteins that may play some role, as yet unknown, in secretion.  相似文献   
35.
丘脑腹后外侧核的神经元对伤害性刺激的反应形式主要为以下三种类型:痛兴奋神经元、痛抑制神经元和痛无关神经元。痛相关神经元的放电活动可被吗啡类药物所抑制。电刺激尾核头部对痛相关神经元主要产生抑制作用,尾核头部背侧的作用强于腹侧,且受不同刺激参数的影响。本文就以上结果在镇痛中的意义进行了讨论。  相似文献   
36.
雄性水狼蛛生殖球顶部的扫描电镜研究   总被引:1,自引:0,他引:1  
本文对我国已知的十一种水狼蛛(蜘蛛目:狼蛛科)生殖球顶部用扫描电镜进行了研究。结果表明,水狼蛛属蜘蛛插入器细长,其后端位于顶突上一突起的凹槽内,顶突作为功能引导器保护着插入器,而无其他狼蛛属具有的次生真正引导器;顶突的形状和其上的突起、顶突与插入器的相互关系对于种的分类与鉴定,特别是对于近似种的区分有较大的参考价值,但仅根据插入器从顶部升起的位置来作为分新属的主要标准,笔者认为还值得商榷和进一步探讨。  相似文献   
37.
强壮水螅的特征及其与寡水螅的种间差别问题   总被引:15,自引:0,他引:15  
一种广泛分布于黑龙江省的大型具柄水螅被暂定为强壮水螅Hydra robusta(IT(?) 1947)。这一中国品系与IT(?)(1947)在日本报告的新种主要特征相同,包括具有精巢乳头。只是精巢乳头不稳定。在实验室条件下第一次有性生殖时每个雄体都发生精巢乳头,但第二次有性生殖时,同一群的后代可全部失去精巢乳头。这是介于强壮水螅与寡水螅Hydra oligactis Pallas(1766)之间的中间性状。从而导致作者做出结论,认为过去其他学者所主张的,以精巢乳头的有无做为鉴别特征来区分强壮水螅和寡水螅是不可靠的。因此,本文又检验了此种水螅的体细胞染色体,证明2n=30,其中第二对染色体上有明显近中位置的次缢痕,最小染色体的长度为最大染色体长度的二分之一以上。这些可做为此种水蝗的鉴别特征。对Niiyama(1944)和Datta(1970)在寡水螅上所做的染色体研究也做了比较及讨论。  相似文献   
38.
用液氮骤冻造成大白鼠交感节前神经变性后,通过神经末梢乙酰胆碱含量、胆碱酯酶活性测定以及电刺激交感干时外周反应等研究其再生规律。结果表明冻伤后3周内再生过程进展迅速,神经结构与功能均有相当程度的恢复;3周后再生过程转慢,直至一年时各指标仍远未达到正常。这证明交感节前神经的再生过程不同于中枢及其它外周神经而独具特征。  相似文献   
39.
兜兰胚胎学的研究   总被引:6,自引:0,他引:6  
云南兜兰花药壁有五层细胞,绒毡层细胞具双核,属分泌型。小孢子母细胞减数分裂为同时型。四分体中四个小孢子呈四面体或左右对称式排列。成熟花粉为二细胞型。单粒分散的花粉包裹于黄色粘性物质中。生殖细胞最初形成的壁为胼胝质的,待游离到营养细胞质中时,具一层很薄的 PAS 正反应的壁,直到花药开裂时这层壁仍存在。成熟花粉无特化的萌发孔,只具薄壁区。胚珠为薄珠心,具一层珠被,胚囊发育为葱型,成熟胚囊为6—8核,胚发育过程中,具2—4细胞胚柄。胚乳具二核。种子成熟时胚柄及胚乳核都消失。成熟种子只具单层细胞的种皮和一个未分化的球形胚。  相似文献   
40.
Two forms of inhibin (A and B), gonadal polypeptide hormones that selectively suppress the secretion of FSH from the anterior pituitary, have been characterized from the porcine and human species, each being composed of a common alpha-chain and one of two distinct, but homologous beta-chains, i.e. alpha beta A and alpha beta B. Using cDNAs encoding the porcine inhibin subunits we have cloned and sequenced the cDNAs encoding the alpha, beta A, and beta B chains of rat ovarian inhibin. Northern analyses of rat testicular RNA with rat ovarian cDNA probes show the presence of mRNAs encoding alpha and beta B chains, but no detectable mRNA encoding the beta A chain under our experimental conditions. This suggests that there may be specific and distinct physiological roles for inhibins A and B. In addition, if there is no extratesticular source of beta A mRNA, then the male rat may be devoid of the stimulators of the secretion of FSH, i.e. activin (beta A beta B) and homoactivin A (beta A beta A), which are derived from the beta subunits of the two inhibins.  相似文献   
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