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161.
贵州省尸食性蝇类的种类和分布   总被引:2,自引:0,他引:2  
陈禄仕 《昆虫学报》2004,47(6):849-952
2000~2002年在贵州不同地区和不同海拔高度,设置采样点12个,在每个季度中间月份的中旬日用诱饵法采集一次尸食性蝇类标本,分析了贵州地区与尸体有关的蝇类及其分布。采集到的尸食性蝇类经鉴定隶属于5科15属25种,其中12种是在贵州首次发现,文中列出了尸食性蝇类名录,分析了它们在贵州的地理分布和季节变化,丰富了昆虫学和法医昆虫学的内容,为法医学推测死者的死亡时间提供了参考依据。  相似文献   
162.
Changing attitudes to nature conservation: the entomological perspective   总被引:1,自引:0,他引:1  
Unlike some other kinds of wildlife, insects have little attraction for the public. Insects tend to be a specialist interest, partly because the numbers of species are so large. This concentrates attention on insect identification and the impossibility of accomplishing this in the field except in a few cases. Some conflict between economic entomologists and conservationists has been apparent. Conservation organizations, including those specifically interested in insects, have influenced attitudes, as has the development of ecology, applied biogeography, and other scientific disciplines. Legislation for insect conservation is not satisfactory; not enough emphasis is laid on habitat conservation and the concepts of protected and endangered species are confused. Better cooperation and understanding between legislators and field entomologists are desirable. Species conservation in Britain emphasises butterflies. Many of the species thought to be threatened with extinction in 1925 are also of priority concern today. Better habitat management and re-establishments, both national and local, are important conservation activities. In the Third World, conservation is closely linked with utilization of the resource. This rational and sustainable use is in accordance with the World Conservation Strategy and benefits the rural poor in areas where attitudes to conservation in the developed world are inappropriate.  相似文献   
163.
昆虫学相关电子期刊资源简介   总被引:1,自引:0,他引:1  
王雁  沈佐锐 《昆虫知识》2004,41(5):495-497
随着文献信息资源的数字化发展 ,网络文献信息以其多方面的优势正渐渐成为教学、科研所依赖的重要资源 ,了解和掌握与学科专业相关的电子资源分布状况是非常重要的。本文着重简述与昆虫学相关的国内外电子期刊资源。  相似文献   
164.
用盐酸吗啡注射家兔,处死后用家兔的不同组织饲养大头金蝇 Chrysomya megacephala初孵幼虫,研究吗啡剂量对大头金蝇幼虫生长的影响及其在法医学中推断死者死亡时间方面的应用。结果显示,在28℃下,取食处理组兔肉和肝脏的大头金蝇幼虫的体长和体重均于孵化后28 h开始在不同程度上大于对照组幼虫,这种趋势一直持续到幼虫末期。在实验的剂量范围内(2.67~10.66 mg/kg),吗啡可促进大头金蝇幼虫的生长。根据大头金蝇幼虫体长和体重推断死者死亡时间时,吗啡的这种影响可使推断值产生的最大偏差达18h。  相似文献   
165.
Chrysomya albiceps is a blowfly of great medical, sanitary and forensic importance widely distributed in the Afrotropical, southern Palaearctic, northern Oriental regions and, recently, in Central and South Americas. Here, we report the characterization of 13 polymorphic microsatellite markers for C. albiceps. The number of alleles ranged from three to 13 alleles with expected heterozygosities ranging from 0.4668 to 0.8408. These markers will be extremely useful for investigating many important aspects of this species such as population structure, dispersal and colonization dynamics.  相似文献   
166.
167.
The spatio-temporal variability of necrophagous fly assemblages in a linear series of habitats from central London to the rural surroundings in the south-west was studied using bottle traps between June 2001 and September 2002. A total of 3,314 individuals in 20 dipteran families were identified from 127 sampling occasions. Calliphoridae accounted for 78.6% of all the dipteran specimens, with Calliphora vicina Robineau-Desvoidy, being the most abundant species (2,603 individuals, 46.9%). Using canonical correspondence analyses (CCA) on 72 fly taxa, six sampled sites and 36 environmental variables, three habitat types corresponding to three groups of flies were identified. These were an urban habitat characterized by C. vicina, Lucilia illustris (Meigen) and L. sericata (Meigen), a rural grassland habitat, characterized by L. caesar (Linnaeus) and a rural woodland habitat characterized by Calliphora vomitoria (Linnaeus), Phaonia subventa (Harris), Neuroctena anilis (Fallén) and Tephrochlamys flavipes (Zetterstedt). Intermediate species (L. ampullacea Villeneuve and P. pallida (Fabricius), located between the three habitats, were also found. Temporal abundance of the 10 most abundant species showed fluctuations between seasons, having low numbers of captured individuals during winter. Correspondence analysis showed clearly seasonal patterns at Box Hill site. The species-habitat associations suggest habitat differentiation between necrophagous guilds in this area and may be of ecological value.  相似文献   
168.
  • 1 Extensive variation to damage by the invasive gall‐forming wasp Leptocybe invasa Fisher & LaSalle (Hymenoptera: Eulophidae) is known to exist amongst Eucalyptus genotypes.
  • 2 In the present study, 30 of the 50 tested genotypes were susceptible to gall formation and development of the wasp. Gall development on the petiole and leaves of plants was compared to calculate the percentage of infestation per plant and per genotype.
  • 3 A positive correlation between galls on petioles and leaves indicated an absence of specificity at this level, and also that either leaves or petioles could be used to obtain an accurate estimate of the level of infestation.
  • 4 Genotypes of E. nitens×E. grandis and E. grandis×E. camaldulensis were most susceptible, with a maximum damage index value for leaves and petioles of 0.52 and 0.39, respectively. Eucalyptus dunii, E. nitens, E. smithii, E. urophylla and E. saligna×E. urophylla showed little or no infestation.
  • 5 The results obtained in the present study suggest that the selection and planting of resistant/less susceptible genotypes will be an important aid in managing damage from L. invasa invasion.
  相似文献   
169.
目的:探讨前交通动脉瘤手术夹闭与介入栓塞两种治疗方法对前交通动脉瘤患者认知功能的影响。方法:采用简易精神状态量表(MMSE)对206例前交通动脉瘤患者进行分析对照,其中开颅动脉瘤夹闭患者125例,介入栓塞患者81例,另取正常组40例作为对照组。结果:前交通动脉瘤患者术前即有认知功能障碍发生,术后患者认知功能障碍发生率增高(P<0.01)。患者组的术后认知功能障碍发生率明显高于对照组,而患者组中的介入组的术后认知功能障碍发生率明显小于手术夹闭组(P<0.05)。结论:前交通动脉瘤患者术前既有认知功能障碍发生,两种治疗手段对术前即出现的认知功能障碍无改善作用,并且可能增加认知功能障碍的发生率及加重认知功能障碍的程度,而介入栓塞术在认知障碍的发生率及出现认知功能障碍的程度方面都优于开颅动脉瘤夹闭术。  相似文献   
170.
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   
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