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101.
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103.
KARSTEN NEUMANN STEFFEN MAAK PETER FRITZSCHE ROLF GATTERMANN 《Molecular ecology resources》2005,5(4):876-878
Ten polymorphic microsatellites were developed for the golden hamster (Mesocricetus auratus), a widely used model organism in biological and medical researches. All loci were used to analyse the microsatellite variability in wild golden hamsters from Syria and in a sample of domestic animals comprising different strains. Average mean expected heterozygosity (HE) and mean allele number (A) of domestic hamsters measured 0.279 ± 0.058 and 2.6 ± 0.306, respectively, compared to 0.809 ± 0.019 and 8.3 ± 1.075 found for wild hamsters. Cross‐species application in other Mesocricetus species proved conservation of most loci throughout the genus. 相似文献
104.
1. Releases of non‐native fish into the wild is an increasing problem posing considerable ecological and genetic threats through direct competition and hybridisation. 2. We employed six microsatellite markers to identify first generation hybrids and backcrosses between native crucian carp (Carassius carassius) and introduced goldfish (C. auratus) and common carp (Cyprinus carpio) in the U.K. We also investigated the genetic characteristics of the taxonomically controversial gibel carp (Carassius spp.) from sites across Europe. 3. Natural hybridisation between goldfish and crucian carp occurs frequently, although hybrids between all other species pairs were observed. Only 62% of British crucian carp populations (n = 21) consisted exclusively of pure crucian carp. In some populations hybrids were so frequent, that no pure crucian carp were caught, indicating a high competitive ability of hybrids. 4. Most hybrids belonged to the F1 generation but backcrossing was evident at a low frequency in goldfish × crucian carp hybrids and goldfish × common carp hybrids. Furthermore, some local populations had high frequencies of backcrosses, raising the opportunity for introgression. 5. Gibel carp from Germany and Italy belonged to two triploid clonal lineages that were genetically closely related to goldfish, whereas all individuals identified from British populations proved to be crucian carp × goldfish hybrids. 6. Our study suggests that the release of closely related exotic cyprinids not only poses a threat to the genetic integrity and associated local adaptations of native species, but may also contribute to shifts in community structure through competitive interactions. 相似文献
105.
Hydrodynamic Analysis of C-start in Crucian Carp 总被引:2,自引:0,他引:2
JunJing XiezhenYin XiyunLu 《仿生工程学报(英文版)》2004,1(2):102-107
The kinematics of turning maneuvers of startled Crucian Carp (Carassius auratus) are presented. All escape response observed are C-type fast-starts. The position of the center of mass and the me,merit of inertia of the fish are calculated. The results show that the position of the center of mass is always at 35% of the length of the fish from the head and the position of the center of mass and rroment of inertia can be considered unchanged during C-start of Crucian Carp. Hydro-dynamic analysis of the C-start is given based on the kinematics data from our experiments. The C-start consists of three stages. In stage 1, the tail fin of fish rapidly flaps in one direction, and a large moment acts on the fish‘s body, which rotates around the center of mass with an angular acceleration. In stage 2, the tail fin flaps more slowly in the opposite direction at slower speed, the fish‘s body rotates around the center of mass with angular deceleration and the center of mass of the fish moves along an are. In stage 3, the moment approximately equals zero, the fish‘s body stops rotating and the center of mass the moves along a straight line. 相似文献
106.
正常与感染粘孢子虫鲫鱼主要组织可溶性蛋白质电泳比较 总被引:2,自引:0,他引:2
采用SDS-聚丙烯酰胺凝胶电泳技术,对正常和感染粘孢子虫的鲫鱼动脉球、肝脏、鳃、脑、肠、肌肉、眼、鳍8种组织可溶性蛋白质进行分析比较。结果表明:病鱼的动脉球、肝脏、鳃、脑、肠5种组织的蛋白质电泳谱带与正常鱼相比有较大变化,动脉球缺失1条谱带同时又诱导出1条新谱带;肝脏有9条谱带缺失;鳃有2条谱带缺失的同时诱导出3条新谱带;脑中新增3条谱带;肠中有5条谱带缺失同时产生3条新谱带。这些变化可作为辅助疾病诊断的生化指标,为从生化水平上揭示该病的致病机理及开展有效的早期防治研究奠定基础。 相似文献
107.
G. E. Nilsson 《Journal of fish biology》1990,36(2):175-179
The tissue distribution of aldehyde dehydrogenase (ALDH) and alcohol dehydrogenase (ADH) in summer-acclimatized crucian carp showed almost the same exceptional pattern as previously found in winter-acclimatized specimens. There was a nearly complete spatial separation of ALDH and ADH; in other vertebrates these enzymes occur together. This exceptional enzyme distribution is probably an adaptation to the extraordinary ability of Carassius to produce ethanol as the major metabolic end product during anoxia. Since the crucian carp is less likely to encounter anoxia during the summer, the present results suggest that the crucian carp is unable to switch over to a 'normal' ALDH and ADH distribution in the summer. However, it is also possible that there is an advantage for the summer-acclimatized crucian carp in keeping ALDH and ADH separate, because of occasional anoxic periods. 相似文献
108.
细菌性败血症引起鲫凝血障碍的研究 总被引:7,自引:0,他引:7
以嗜水气单胞菌感染体重70g左右的鲫并检测了感染鱼和对照鱼的血液学及播散性血管内凝血判定指标等参数。结果表明细菌性败血症病鱼严重贫血,存在明显的凝血障碍,在疾病发展过程中存在播散性血管内凝血现象。这一些象导致了病鱼全身性出血,并在疾病的病理生理过程中起了重要作用。 相似文献
109.
本实验采用辣根过氧化物酶(HRP)逆行追踪技术对鲫鱼尾部神经分泌系统进行了研究,结果表明,尾部神经分泌细胞可分为大(60-70μm)、中(40-50μm)、小(20-30μm)三种类型,在尾部脊髓的背侧面和腹侧面都有分布,HRP的引入采用Griffin(1979)提出的缓释胶法,结果证明这种方法在鱼类神经解剖的束路示踪方而是可行的。 相似文献
110.
采用聚丙烯酰胺圆盘电泳方法,分析了金黄地鼠血清,肝脏,心脏和骨骼肌4种组织的碱性磷酸酶同工酶。结果表明,在同种动物中不同组织的碱性磷酸酶谱具有明显的组织特异性,并且各部门酶带有重叠现象。在不同组织中碱性磷酸酶具有特异性,这是与各组织的生理功能相适应的结果。 相似文献