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61.
62.
2015年7月,于四川省若尔盖县采集到亚洲蝮属蛇类标本2号,雌雄各1号,经形态学比对和基于线粒体基因ND4片段的单倍型网络分析,证实该蛇为阿拉善蝮(Gloydius cognatus),系四川省蛇类新纪录。  相似文献   
63.
Evaluation of damage to physic nut (Jatropha curcas) by true bugs   总被引:4,自引:0,他引:4  
The type of injury and amount of damage to the fruits and seeds of physic nut (Jatropha curcas L., Euphorbiaceae) caused by two species of fruit feeding true bugs, Pachycoris klugii Burmeister (Heteroptera: Scutelleridae) and Leptoglossus zonatus (Dallas) (Heteroptera: Coreidae), and the flower feeding true bug, Hypselonotus intermedius Distant (Heteroptera: Coreidae), were assessed using field cages. The parameters analysed were infructescence, fruit, seed and seed kernel weight, seed length, fruit and seed abortion, seed malformation and oil and protein content of the seed kernels. All three species reduced overall yield. The two members of the fruit feeding guild led to premature fruit abortion and malformed seeds. Reduction of fruit, seed and seed kernel weight as well as seed length could be expressed as linear regressions of adult population densities. The oil content of the seeds was slightly reduced by the bugs, but protein content remained unchanged. Damage increased with the developmental stage of the larvae. Whereas adult L. zonatus of both sexes produced more damage than the nymphs, female P. klugii caused less damage than nymphs, and male P. klugii no significant damage at all. H. intermedius is a pollinator of this entomogamous plant. At high densities, however, it reduced the number of fruits maturing.  相似文献   
64.
Streptococcus intermedius is well known to produce severe infections in various areas of the body. In this study, we evaluated the ability of S. intermedius to utilise human transferrin as a source of iron and investigated the mechanism by which iron can be obtained from this plasma protein. Adding either ferrous sulfate or holotransferrin to an iron-deficient culture medium allowed growth of S. intermedius. Cultivation of S. intermedius under an iron-poor condition was associated with the over expression of a 58 kDa cell surface protein. Neither siderophore activity nor reductase activity could be detected. Moreover, cells of S. intermedius did not show transferrin-binding activity or proteolytic activity toward transferrin. It was found that S. intermedius could rapidly decrease the pH of the medium during cell growth, resulting in a release of iron from holotransferrin. When the buffering capacity of the culture medium was significantly increased, the holotransferrin could not support growth of S. intermedius. It is suggested that under certain circumstances, S. intermedius may migrate from its normal niche (oral cavity), reach a particular site and create a localised environment where the pH can be lowered with the subsequent release of iron from transferrin. This would allow bacterial growth and initiation of the infectious process.  相似文献   
65.
Activation of the dopamine type-D2 receptor in late gastrula of sea urchins is known to decrease the growth rate of post-oral arms of larvae, and, as a result, the phenotype of these larvae mimics that of larvae developing in the abundance of food. Our data indicate that the effect of dopamine on sea urchin larvae is stage-dependent. In our experiment, the early four-armed plutei (96 hours post fertilization, hpf) of Strongylocentrotus intermedius had substantially shorter post-oral arms if they developed from the larvae treated with dopamine at the early pluteus stage (48 hpf), when they had already formed the first dopaminergic neurons, as compared to the plutei from the larvae treated with dopamine at the mid to late gastrula stage (24 hpf), when they did not have any neurons yet. The pre-treatment of larvae in 6-hydroxydopamine, a neurotoxic analog of dopamine that specifically disrupts activity of dopaminergic neurons, prevented the development of the short post-oral arms phenotype in larvae. These results confirm the assumption that dopaminergic neurons play an important role in the development of the short post-oral arms phenotype in sea urchin larvae. Another finding of our study is that the dopamine treatment also affects the growth of the body rods and the overall larval body growth. Based on these observations, we suggest researchers to carefully select the developmental stage, pharmacological agents, and incubation time for experimental manipulation of sea urchin larvae phenotypes through dopaminergic nervous system.  相似文献   
66.
Chondroitin 6-sulfate depolymerizing activity was examined in the culture supernatant of Streptococcus intermedius ATCC 27335. 2-Acetamido-2-deoxy-3-O-(beta-D-gluco-4-enepyranosyluronic acid)-6-O-sulfo-D-galactose was split from the substrate. The enzyme(s) was not active upon chondroitin 4-sulfate or dermatan sulfate, which indicated that the enzyme responsible for the depolymerization is chondroitinase C.  相似文献   
67.
目的对雪貂分离菌株进行鉴定。方法通过菌落、菌体形态、生化特征等细菌学检测方法和药敏实验对所分离菌株进行鉴定。结果根据生物学特性和药敏实验确定所分离菌株为金黄色葡萄球菌和中间葡萄球菌。结论分离菌株为金黄色葡萄球菌和中间葡萄球菌。  相似文献   
68.
69.
冯庆  王应祥 《动物学研究》1996,17(4):443-450
本文报道了笼养条件下出生的20胎41仔(26♂♂,15♀♀)间蜂猴的生长发育的研究,其研究内容及结果如下:(1)体重,体长,前肢长,后肢长,耳长和尾长的生长方程及头骨的瞬时增长率,表明间蜂猴属快速生长的早熟类群。(2)幼猴的成猴毛色有一个由浅变深的过程,面部皮肤(包括耳,鼻,眼圈)及手足皮肤从幼猴到成猴有一个明显的变化,幼猴为浅粉红色,成猴为黑色,(3)初生幼仔门齿,犬齿,第1前臼齿已被龈萌发,1  相似文献   
70.
长江中下游地区的短尾蝮分类地位的确定   总被引:1,自引:0,他引:1  
王湘君  赵尔宓 《四川动物》2007,26(2):250-254
长江中下游地区的短尾蝮的鼻间鳞形状与斑纹和短尾蝮(Cloydius brevicaudus)和日本蝮(G.blomhoffii)相似,鳞片变化范围也有很大重合。尽管不少学者对此进行过研究,至于它们的分类地位尚有争议。作者对中国产蝮亚科(Crotalinae)亚洲蝮属(Gloydius)短尾蝮(Gbrevicaudus)、乌苏里蝮(G.ussuriensis)和长江中下游短尾蝮共3个居群9个个体测定了825bp线粒体ND4基因序列,并从GeneBank下载了日本产日本蝮(Gblomhoffii)2个个体的ND4基因序列,以原矛头蝮属(Protobothrops)的菜花原矛头蝮(P.jerdonii)序列为外群,以亚洲蝮属的高原蝮(G.strauchii)序列为姐妹群,用MEGA3.1软件构建最大简约分子系统树。结果显示,长江中下游地区的短尾蝮与东北地区的短尾蝮聚集,而乌苏里蝮与日本蝮聚集,支持长江中下游地区的短尾蝮不是日本蝮的结论。还对其体长和鳞片(背鳞、腹鳞和尾下鳞)数据做了统计学分析,并和东北短尾蝮的数据比较。运用75%法则,两者所有数据的差异系数均小于1.28,认为长江中下游地区的短尾蝮是东北地区短尾蝮的南方居群,而不是其亚种。  相似文献   
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