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11.
Olfaction in Lepidoptera   总被引:14,自引:0,他引:14  
Odours play a very important role in the life of insects belonging to the order Lepidoptera. In the present paper, a review is given of the current knowledge of morphology, development and function of the olfactory system in larval and adult moths and butterflies. Research regarding both the antennal and accessory olfactory pathways, as well as both the pheromone and the host odour detecting systems, is reviewed.  相似文献   
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Summary Using the peroxidase-antiperoxidase immunohistochemical technique, carnosine-like immunoreactivity was demonstrated to localize specifically within the primary olfactory neuron.This study was supported by grants from the Ministry of Education, Science and Culture, Japan (No. 61218016). Reprint requests to I. N., Department of Anatomy, School of Medicine, Fujita-Gakuen Health University, Toyoake, Aichi 470-11, Japan.  相似文献   
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Acute emetic response to relatively low-doses of X-irradiation on suncus (Suncus murinus) was examined. The behaviors recorded for each subject, using a video-cassette recorder system, were (1) the number of emesis, during exposure to a dose of 3.0 Gy; (2) emesis threshold. Results showed that the emetic threshold was observed at 0.85 Gy, and the number of radioemesis during exposure was 29. However, the observed threshold dose became 2.22 Gy following olfactory bulbectomy. The emetic number decreased significantly (p<0.01), and reached a value one-fourth of the sham-control. The bulbectomized suncus showed a resistance to X-irradiation. Furthermore, I examined whether the animals could also acquire radio-resistance when they were subjected to a brief of dose X-ray (0.3 Gy) prior to a exposure to 3.0 Gy. Results showed that brief pre-exposure increased the observed threshold, a pattern that was exactly the same as shown in the bulbectomized animals. Increasing the pre-exposure dose further to 0.45–0.60 Gy, however, resulted in the complete disappearance of the effect. These results suggest that only the mice pre-irradiated with 0.30 Gy acquired resistance to radiation-induced emesis.  相似文献   
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为了获得被动型氢原子钟高、低能态氢原子经四极磁选态器偏转后在储存泡口的分布规律,建立了更加贴近实际情况的分布模型.利用统计学方法,一定温度下的氢原子出射速度采用麦克斯韦分布,出射角度近似采用均匀分布,并结合氢原子在四极磁选态系统中的运动规律,通过数值计算得到了距四极磁选态器出口一定距离处高、低能态氢原子的三维分布密度.应用该分布模型,计算得到收集高能态氢原子的泡口优化半径与聚焦距离之间的关系,为储存泡的加工和聚焦距离的设计提供了依据,可以使得高能态原子被最大程度聚集,低能态原子被偏离,从而提高谐振腔内跃迁信号的功率.  相似文献   
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Finding a mate is a crucial step in sexual reproduction. The mutualism between figs and their pollinators is exploited by many figwasps that develop within their galls and attain sexual maturity simultaneously. Male pollinators carry the specific burden of detecting and opening mating holes in galls containing conspecific females before mating with them. The mating behaviourand antennal sensilla of male pollinators associated with Ficus semicordata was investigated to understand mate recognition. Male Ceratosolen gravelyi located female-containing galls from a distance, but only attempted to chew a mating hole after antennal contact with the gall surface was made. They showed similar responses to females and body extracts but failed to respond to washed female bodies. This behaviour indicates that unidentified chemicals present on the body surfaces of females are sufficient to elicit olfactory attraction and tactile confirmation. Multiporous plate sensilla are candidates for olfactory reception from a distance while basiconic sensilla may be involved in contact chemoreceptor. All of the sensilla are highly localised, on the distal part of the terminal flagellomere, suggesting a response to selection for strong directionality in the complex odour environment of the fig in which messages produced by hundreds of females may confuse precise mate localisation.  相似文献   
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用嗅觉去感受世界--2004年诺贝尔生理学或医学奖成果简介   总被引:1,自引:0,他引:1  
嗅觉系统对我们的生活非常重要,人类和其它哺乳动物利用嗅觉系统可以识别环境中巨大数量的化学物质。嗅觉是如何产生的?为解开这个难题,美国两位科学家阿克塞尔和巴克从编码气味受体的基因入手,发现了识别气味分子的受体,并且证明了嗅觉系统的组织方式,从而告诉世界我们是如何感受气味的。为表彰两人的贡献,Karolinska医学院诺贝尔奖评审委员会决定授予他们2004年诺贝尔生理学或医学奖。介绍了两位科学家是如何破解这个难题的。  相似文献   
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量子点经嗅觉通道进入中枢神经系统的可视化过程   总被引:4,自引:0,他引:4  
模拟纳米颗粒呼吸道暴露及鼻腔给药模式, 给ICR雌性小鼠鼻腔滴注量子点溶液, 用动物活体荧光成像系统和荧光显微技术观察小鼠鼻腔、嗅球及大脑等组织中量子点分布随时间的变化情况. 动物活体荧光成像可见, 鼻腔滴注量子点30 min后, 量子点溶液扩散到嗅球, 2 h后鼻腔荧光强度逐渐变弱, 24 h仅在嗅球部位仍有可见荧光. 荧光显微镜观察组织切片可见, 滴注30 min时, 量子点仅存于嗅球前端边缘, 1 h后进入嗅球, 并向嗅球深层转移, 24 h后发现嗅球内量子点荧光变弱, 并在大脑组织切片内观察到量子点荧光. 结果表明, 纳米颗粒可以经过鼻黏膜进入脑组织, 分布于嗅球、大脑等部位.  相似文献   
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