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151.
巨尾阿丽蝇幼虫发育形态学及其在死者死亡时间推断中的应用 总被引:9,自引:4,他引:5
为了明确对于凶杀案件中死亡时间判断有重要意义的蝇类幼虫的形态特征变化规律,分别在12、16、20、24和28℃下饲养了巨尾阿丽蝇Aldrichina grahami (Aldrich)并定期取样,显微镜下观察其形态变化。结果表明:后气门形态、表皮、消化道等随时间而发生的规律性变化可作为幼虫日龄的标志。据此将幼虫期划分为:1龄期、2龄早期、2龄后期、3龄叠气门期、开环期、浅闭环期、深闭环期、圆锥期。到达上述各发育阶段的时间决定于温度。 相似文献
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八十年代以来以基因工程技术为主导的分子生物学研究大大丰富了人们对生命过程和本质的认识。基因工程技术在昆虫学研究中日益受到重视。一个新兴的学科─-昆虫分子生物学已经形成。在分子生物学研究中基因探针是必不可少的重要的工具。由于在系统进化上人和哺乳类遗传距离较近,其基因探针具有较大的通用性,所以医学发展起来的人基因探针为哺乳动物研究带来了许多方便。而无脊椎动物的分子生物学研究一向十分薄弱,因此可用于昆虫的基因探针来源困难,研究者常需在实验设计初期对已有的众多基因探针进行预选或自己制备。所以基因探针的选择和使用对昆虫分子生物学研究至为关键。本文就昆虫学常用的基因探针的类型,标记方法,特别是应用等方面选择若干典型实例作一些介绍和评述。 相似文献
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155.
Khesller P.O. Name Karine B. Barros‐Cordeiro José B. Gama Filho Marta Wolff José R. Pujol‐Luz Sônia N. Báo 《Journal of morphology》2012,273(2):160-172
Morphology of male internal reproductive organs, spermatozoa, and spermiogenesis of the blow‐flies Lucilia cuprina, Lucilia eximia, and Lucilia peruviana is first described here, using light and transmission electron microscopy. Spermiogenesis follows the characteristics described for others insect species. The spermatozoa of L. cuprina are similar to those described for other Brachycera. However, in L. eximia and L. peruviana, some differences were found. In L. cuprina and L. eximia species, the spermatozoa are long and thin, measuring about 211 μm and 146 μm in length, of which the head region measures approximately 19 μm and 17 μm, respectively. A polymorphism was observed in L. cuprina and L. eximia spermatozoa. In all three species, the head includes a monolayered acrosome with electron‐lucent material. The shape of the nucleus, in cross sections, varies from circular to oval with completely condensed chromatin. Implantation of the axoneme was observed in the middle region of the nucleus, known as the “peg” region. In the next region, the beginning of two mitochondrial derivatives of similar diameter and different lengths in L. cuprina and only one in L. eximia and L. peruviana was observed. In the overlap region, the following structures were observed: nucleus, centriolar adjunct, mitochondrial derivatives, and axoneme. The axoneme is of a conventional insectan type with a 9 + 9 + 2 microtubular arrangement. The male internal reproductive tract consists of testis, deferent ducts, a strongly developed seminal vesicle, accessory glands, and ejaculatory duct. These features are consistent with the structural diversity of the dipteran reproductive tract and spermatozoa, comprising an essential tool for understanding the complex variations found in the Diptera. J. Morphol. 2011. © 2011 Wiley Periodicals, Inc. 相似文献
156.
用致死剂量盐酸吗啡注射家兔,处死后用其肌肉在恒温25℃条件下饲养大头金蝇Chrysomyia megacephala初孵幼虫,研究吗啡对大头金蝇生长发育的影响,及其用于法医学中推断死者死后间隔时间(Postmortem interval,PMI)方面的初步探讨.结果 显示,在25℃下孵化64 h后,处理组大头金蝇的体长、体重及蛹长、蛹重明显大于对照组幼虫(P<0.05),这种趋势一直持续到羽化.吗啡缩短了大头金蝇的发育历期,根据大头金蝇发育历期进行PMI推断时,吗啡可使PMI推断值缩短14.7 h. 相似文献
157.
María Prez‐Marcos Elena Lpez‐Gallego María Isabel Arnaldos Dolores Martínez‐Ibez María Dolores García 《Entomological Science》2020,23(3):297-310
The Formicidae are considered crucial components of the entomosarcosaprophagous fauna because they can delay the decomposition process, cause tissue postmortem damage and produce bloodstain patterns that may confuse investigations. Moreover, some studies suggest that the Formicidae can act as environmental and seasonal indicators. However, studies on this group on vertebrate carcasses are scarce, especially in the Iberian Peninsula and the southwest of Europe. Thus, comparative studies at different altitudes in a protected wild mountain area could provide useful information on its composition in such environmental conditions, their role as environmental indicators and their forensic implications. For this reason, the Formicidae sarcosaprophagous community was studied at three different altitudes, between 400 and 1,500 m, in a wild mountainous area in the southeast of Spain using a modified Schoenly trap, with two pitfall traps inside, baited with 5 kg piglets (Sus scrofa L.). This work illustrates an approach to the community of the Formicidae, as a representative of the sarcosaprophagous community in an altitudinal gradient, showing a great variability in its composition. Furthermore, when comparing our results with other studies carried out in the Iberian Peninsula, we are able to suggest certain species with a potential utility as geographic and environmental indicators. Thus, Iberoformica subrufa, Lasius brunneus, Lasius cinereus and Camponotus sylvaticus are species of special interest as they appeared in either one of the sampled areas or in the same region. 相似文献
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The occurrence of precocious egg development in forensically important calliphorid species has previously been reported; however, the frequency of occurrence in both wild and captive colonies, and the consequent effects on developmental studies and post-mortem interval (PMI) estimates, are largely unknown. A PMI estimate based on samples developed from precocious eggs could be extended by the entire period of embryogenesis, which at 22 °C would result in a significant error of around 24 h. This study examined the occurrence of precocious egg development in Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae) wild-caught and captive-bred adults by investigating the presence of larvae in the adult female genital chamber and by monitoring hatching times of entire batches of eggs throughout embryogenesis, respectively. A total of 8.82% of gravid wild-caught females contained a larva in the genital tract (i.e. a precocious egg). This indicates that all specimens collected should be considered potentially precocious for the purpose of PMI estimation. Less than 2.55% of a batch of eggs laid by captive females were precocious; protocols for minimizing the effect of precocious eggs on developmental studies are suggested. 相似文献
160.
2006—2010年5年来,我国昆虫学工作者获得了国家自然科学基金736项、国家科技支撑计划2项19个课题,公益性行业科研专项34项,"973"项目6项;共发表与昆虫有关的学术论文13772篇,其中SCI收录论文2625篇,Science6篇,Nature1篇,PNAS6篇,Annual Review of Entomology1篇,Nature Bioteachnology4篇;获得了国家科技进步奖二等奖13项。本文分析了2006—2010年我国昆虫学研究项目、研究成果在不同昆虫学分支学科和不同研究区域的分布特征,透视了我们昆虫学研究前沿,旨在为制定我国昆虫学未来发展战略提供基础信息。 相似文献