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1.
亚成体中华蟾蜍端脑形态学与组织学的初步研究   总被引:1,自引:1,他引:0  
为了探讨亚成体端脑的形态学和组织学特点,充实比较发育神经生物学的研究资料,本文采用脊椎动物神经标本制作技术和常规HE染色法,初步研究了亚成体中华蟾蜍端脑的形态学和组织学结构.结果表明:嗅球位于大脑半球的腹前外侧,细胞从外到内大致可分为7层结构;大脑半球内原始海马较原始梨状区发达;隔区位于原始海马的下方,有外侧隔核和内侧隔核之分;侧脑室的侧壁有内侧界沟区将始海马和隔区分开,也有外侧界沟作为原始梨状区和纹状体的分界;少量脉络丛伸入侧脑室;杏仁核是位于第三脑室两侧的两个细胞核团;纹状体是位于原始梨状区下方和侧脑室底部的细胞团,在两个侧脑室连通时较明显.此外,亚成体端脑内细胞形态和大小分化较为单一.本实验在一定程度上填补了有关无尾两柄类神经系统资料的空白.  相似文献   

2.
Green sturgeon, Acipenser medirostris, are the most marine-oriented of North American sturgeons. However, their estuarine/marine distribution and the seasonality of estuarine use are largely unknown. We used acoustic telemetry to document the timing of green sturgeon use of Washington estuaries. In the summers of 2003 and 2004, uniquely coded acoustic transmitters were surgically implanted in green sturgeon captured using commercial gillnets. All sturgeon tagged were greater than 1.2 m total length. They were caught, tagged, and released in both Willapa Bay (n = 49) and Columbia River (n = 11) estuaries. We deployed an array of four fixed- site acoustic receivers in Willapa Bay to detect the estuarine entry and exit of these and any of over 100 additional green sturgeon tagged in other systems during 2003 and 2004. Green sturgeon occurred in Willapa Bay in summer when estuarine water temperatures exceeded coastal water temperatures by at least 2°C. They exhibited rapid and extensive intra- and inter- estuary movements and green sturgeon from all known spawning populations were detected in Willapa Bay. We hypothesize that green sturgeon optimize their growth potential in summer by foraging in the relatively warm, saline waters of Willapa Bay and we caution that altering the quality of estuarine habitats could negatively affect this species throughout its range.  相似文献   

3.
爪鲵消化系统的解剖学和组织学初步研究   总被引:5,自引:0,他引:5  
本文报道了爪鲵消化系统的形态学和组织学结构特点。爪鲵口腔底部具有肌肉质的舌,食管很短,胃是呈纺锤形的长囊,胃壁较厚,粘膜厚,胃腺发达。消化管肌层皆为平滑肌,环肌明显多于纵肌。肝脏较大,分左、中、右三叶;有胆囊;胰腺长带状,胰管与胆管汇合后与小肠最前部的十二指肠相连。  相似文献   

4.
以透明骨骼双色法对挂榜山小鲵(Hynobius guabangshanensis)成体和亚成体舌器的形态特征进行观察和详细描述。结果表明,在成体中,下舌软骨中部交叉;角舌软骨末端被第一下鳃骨和第一角鳃骨的愈合体遮盖;具有基鳃软骨角状突;第二角鳃骨骨化;尾舌骨骨化,呈"一"字形。在亚成体中,下舌软骨中部未交叉;第一下鳃骨和第一角鳃骨单独存在;无基鳃软骨角状突;第二角鳃骨未骨化;具有第三、第四对角鳃骨,且均为软骨;尾舌骨未骨化,成"1"字形。这些形态特征的改变可能由舌器在成体和亚成体阶段的功能所引起。  相似文献   

5.
对成年日本新糠虾(Neomysis japonica)雄性生殖系统的解剖特征和组织结构进行了观察,结果表明,日本新糠虾雄性生殖系统由精巢、输精管和交接器组成,整体似“n”形。精巢左右对称,由一条“n”形的精索和其外侧延伸形成的19~21个精母细胞囊及与之相连的19~21个精子细胞袋组成,精子细胞袋位于精母细胞囊背部偏外侧的位置,通过一个短窄的通道与输精管相连。输精管是一个“n”形的管子,位于精索的背面,其前段连着精巢,后段逐渐变细,直至第8胸节向腹部弯曲变得更细,随后膨大形成壶腹,壶腹向后通入交接器中并在末端膨大。交接器位于身体的腹中线附近,其壁由外层的角膜层和内层的上皮细胞层组成,具有防御和保护功能;其内的肌肉层加厚,外层为环肌层,内层为纵肌层。从精索,经精母细胞囊,到精子细胞袋依次分布着不同发育阶段的精细胞。成熟精子有头部和尾部两部分,头部较短,尾部相当长,且头尾之间有一个15°的转角。精子呈簇分布形成精子束,精子束通过精子细胞袋与输精管间的通道被输送到输精管中,并沿输精管向交接器运输。  相似文献   

6.
Adult zebrafish have an amazing capacity to regenerate their central nervous system after injury. To investigate the cellular response and the molecular mechanisms involved in zebrafish adult central nervous system (CNS) regeneration and repair, we developed a zebrafish model of adult telencephalic injury.In this approach, we manually generate an injury by pushing an insulin syringe needle into the zebrafish adult telencephalon. At different post injury days, fish are sacrificed, their brains are dissected out and stained by immunohistochemistry and/or in situ hybridization (ISH) with appropriate markers to observe cell proliferation, gliogenesis, and neurogenesis. The contralateral unlesioned hemisphere serves as an internal control. This method combined for example with RNA deep sequencing can help to screen for new genes with a role in zebrafish adult telencephalon neurogenesis, regeneration, and repair.  相似文献   

7.
8.
This article focuses on the differential diagnosis of pathologic lesions recorded on the limbs and crania of 17 subadults from two pre-European burial mounds in Tonga, western Polynesia. All affected subadults were between the ages of 6 months and 3 years at death. The lesions described consist primarily of subperiosteal new bone deposition on the limbs and endocranial surface. However, the presence of cribra orbitalia in a number of individuals indicates concurrent iron-deficiency anaemia. A differential diagnosis of haematogenous osteomyelitis, congenital syphilis, yaws, scurvy, hypervitaminosis A, trauma, Caffey's disease, and iron-deficiency anaemia is discussed. It was concluded that the most likely cause for the lesions observed is a synergistic relation between infection (weanling diarrhoea, yaws) and metabolic disease (scurvy and possibly hypervitaminosis A). Trauma is not ruled out as contributing to the development of some pathologic lesions. It is concluded that, in the Pacific Islands at least, multiple causes for skeletal pathology in subadults should be considered rather than a single aetiology.  相似文献   

9.
During a four-year period at Tanjung Puting Reserve, Central Indonesian Borneo, subadult males were observed for 670.5 observation hours, 463 hours of which were as focal individuals. Subadult males were quite gregarious, participating in groupings for 40.9% of the time they were observed as targets. Subadult male sociality centered around females; 83% of the time subadult males spent in groupings was exclusively with females, as compared to 3% of contact time spent exclusively with other males. Much subadult male sociality can be understood in terms of male-male competition for females. Interactions between adult and subadult males were almost entirely determined by the presence or absence of females. Adult males were more belligerent when females were present. Twenty-two copulations or attempted copulations occurred during 16 subadult male-female encounters, two of which were consortships. The majority of subadult male copulations (86%) were resisted matings. Outside of consortship, resisted matings (or the first in a series of resisted matings or attempts) usually took place at encounter or shortly thereafter. Subadult males also surreptitiously followed adult males and their consorts. Subadults frequently located receptive females before adult males did but were replaced by adult males when these appeared. Subadult male reproductive strategy consisted of both sneak/“rape” and consort tactics with sneak/“rape” predominating.  相似文献   

10.
爪鲵呼吸器官的胚后发育   总被引:1,自引:0,他引:1  
应用石蜡切片和扫描电镜技术,对爪鲵(Onychodactylus fischeri)幼体、亚成体和成体3个不同发育阶段的皮肤、外鳃、咽等呼吸器官进行了显微观察与比较分析,旨在揭示爪鲵不同发育阶段各呼吸器官的演化规律.结果表明,爪鲵的皮肤随年龄的增长而逐渐增厚,幼体阶段其背腹皮肤厚度相差不大,亚成体及成体背部皮肤明显厚于腹部;外鳃是幼体和亚成体爪鲵呼吸器官的重要组成部分,随着发育外鳃逐渐完善,到亚成体阶段达到顶峰,随后逐步退化;咽部是爪鲵的重要呼吸器官,幼体期口腔和咽发育不完善,亚成体咽部逐渐发育,至成体时发育完善.  相似文献   

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