共查询到19条相似文献，搜索用时 546 毫秒
1.
为了深入了解斑马鱼端脑的微细形态和超微结构,采用光镜和电镜技术对斑马鱼端脑进行观察研究。斑马鱼端脑由左、右嗅球和左、右大脑半球构成。嗅球前方有一对嗅神经,后端伸出嗅茎与大脑半球联系。光镜下,嗅球组织结构从外向内依次为上皮层、神经纤维层、小细胞层和内部细胞层。大脑半球外部覆盖很薄的大脑皮,基部为纹状体,两者之间的腔隙为公共脑室。纹状体由神经核团和神经纤维构成。神经核团分布于纹状体周缘,主要有连前核、背嗅核、侧嗅核、视前核和脚内核等。神经纤维包括横行的前连合,纵行和斜行的中央嗅束和侧嗅束。电镜下,嗅球分层明显,可观察到僧帽细胞、神经胶质细胞和众多突触。大脑半球中可见神经胶质细胞、突触以及血脑屏障系统等。斑马鱼端脑形态结构与大多数硬骨鱼相似,但有个别核团存在差异。实验结果可为斑马鱼神经生物学模型的建立与应用提供有效的理论基础。 相似文献
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中国对虾循环系统的发生 总被引：1，自引：0，他引：1
采用组织学方法。研究了中国对虾循环系统的发生过程，在无节幼体第3期，起源于头胸甲皱褶部位的腹侧中胚层细胞通过增殖向背面迁移，在中肠的背面形成一中胚层板，此板两侧向背面上卷，合拢而成心脏，与此同时，该中胚层板两侧周围的中胚层细胞向两侧迁移，与体壁接触形成围心腔，心孔出现在无节幼体第5期，是由该处的心壁细胞直接内陷形成；心脏的形态结构随着幼体的发育而不断完善，至蚤状幼体第1期以后，组成心壁的细胞分化为单层的心肌细胞，随后其外包被一层由结缔组织细胞形成的心外膜，至仔虾期，心脏的外形和结构已与成虾的相似；背腹动脉发生的方式与时间和心脏的相同；中背动脉的发生包括两部分；心脏近端的中背动脉由心脏前端延伸而成，心脏远端的中背动脉则由幼体前端背部中胚层细胞形成，血细胞最早出现在无节幼体第1期。 相似文献
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虹鳟消化器官的显微结构观察 总被引：1，自引：0，他引：1
将体质健壮的虹鳟解剖,取出胃、肠、肝脏和胰脏等消化器官,经Bouin氏液固定、石蜡包埋、切片、H.E染色和显微摄像。经仔细观察:虹鳟胃膨大,胃壁横纹肌发达,幽门垂多而长;肠壁薄,明显分为黏膜层、黏膜下层、肌肉层和浆膜层,其中黏膜层薄而长,黏膜下层富含血管,肌肉层内环肌由较厚的平滑肌细胞交叠而成,外纵行肌相对较薄,细胞密集,浆膜层细胞结实。肝脏和胰脏细胞较大,胰脏是单独的器官,不与肝脏混杂在一块。 相似文献
4.
皱纹盘鲍心脏,肾脏,粘液腺和足的组织学研究 总被引：2，自引：0，他引：2
对锼纹盘鲍心脏、肾脏、粘液腺和足的组织学结构进行了研究，观察发现，鲍心室壁和心耳壁由外膜层和心肌层组成，心耳外膜形成囊泡状结构；肾实质由众多的肾小管及集合管组成；粘液膜由位于外套膜凹陷处的粗大粘液腺组织组成；足由外至里的组织结构依次是麦皮，皮下组织和肌组织、足底部和四周边缘的组织结构不尽相同。 相似文献
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《水产科学》2015,(7)
应用组织病理学方法,对感染小瓜虫草鱼幼鱼的脑、心脏、鳃、鳍、头肾、中肾、上颌、皮肤肌肉及内脏团等组织器官进行观察。观察结果表明,各组织器官均有明显的组织病理学变化,鳃丝、上颌、胸鳍及背鳍等组织器官可见小瓜虫寄生;脑组织淤血;心耳、心室及动脉球内发生淤血;鳃丝淤血并有炎细胞浸润,部分鳃小片结构消失,呼吸上皮细胞脱落;头肾淤血;中肾肾小管、连接小管的上皮细胞内出现脂肪样变及玻璃样变,肾小球肿大导致肾小囊囊腔消失,肾间质淤血;腹皮下致密层胶原纤维发生玻璃样变,静脉淤血;肠道黏膜层部分上皮细胞脱落,严重者上皮细胞溶解消失,黏膜下层可见炎细胞浸润;肝胰脏内肝血窦、静脉淤血,肝脏局灶性坏死;脾脏内静脉淤血。 相似文献
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用大体解剖和光镜技术对暗纹东方鲀幼鱼的消化道进行了形态学和组织学观察。暗纹东方鲀消化道可分为口咽腔、食道、胃、小肠和直肠5部分,食道与胃、胃与小肠、小肠与直肠间均存有明显的缢缩。咽后消化道的管壁组织可分为4层:粘膜层、粘膜下层、肌层和浆膜层。食道的粘膜上皮为复层扁平上皮细胞,上皮层内含有大量杯状分泌细胞。胃、小肠和直肠的粘膜上皮均为单层柱状上皮,具纹状缘。胃明显膨大,呈"J"型,胃长约占整个消化道长的1/5,未见胃腺存在。胃体中底部粘膜褶明显增多,并多次回复折叠。小肠粘膜褶发达呈多分支状,直肠粘膜褶向肠腔突起呈乳头状。 相似文献
7.
弗氏柠檬酸杆菌感染诱导斑马鱼皮肤免疫相关基因的差异表达 总被引：2，自引：1，他引：1
从草鱼肠道中分离到1株细菌,通过形态学观察、生理生化特征和16S rDNA序列分析等鉴定为弗氏柠檬酸杆菌,动物试验结果表明,该菌对斑马鱼有致病性;从感染诱导的斑马鱼皮肤组织中提取总RNA,经Biotin荧光标记与拥有15 617个cDNA片段的斑马鱼基因芯片(affymetrix)杂交筛选分析,获得斑马鱼皮肤免疫相关差异表达基因88个,其中有74个上调表达基因和14个下调表达基因;进一步根据基因功能聚类(GO)分析,初步将88个差异表达基因分为8个生物学功能,其中主要参与补体激活、急性期反应、应激防御反应、细胞凋亡、抗原加工提呈、细胞迁移粘附、凝血因子和血小板激活等免疫应答过程;同时进行信号通路(pathway)分析,结果表明MAPK(hsp70、daxx、nfkbiab)、JAK/STAT(ifn1)和TGF-β(thbs1)等信号通路参与斑马鱼皮肤抗弗氏柠檬酸杆菌感染免疫应答。采用基因芯片方法筛选与鱼类皮肤免疫相关的功能基因,为将来以斑马鱼为模型研究鱼类皮肤局部免疫应答的分子机制提供科学依据。 相似文献
8.
暗纹东方纯幼鱼消化道的形态学和组织学研究 总被引：2，自引：0，他引：2
用大体解剖和光镜技术对暗纹东方鲍幼鱼的消化道进行了形态学和组织学观察。暗纹东方纯消化道可分为口咽腔、食道、胃、小肠和直肠5部分，食道与胃、胃与小肠、小肠与直肠间均存有明显的缢缩。咽后消化道的管壁组织可分为4层：粘膜层、粘膜下层、肌层和浆膜层。食道的粘膜上皮为复层扁平上皮细胞，上皮层内含有大量杯状分泌细胞。胃、小肠和直肠的粘膜上皮均为单层柱状上皮，具纹状缘。胃明显膨大，呈“J”型，胃长约占整个消化道长的1／5，未见胃腺存在。胃体中底部粘膜褶明显增多，并多次回复折叠。小肠粘膜褶发达呈多分支状，直肠粘膜褶向肠腔突起呈乳头状。 相似文献
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Atlantic cod, Gadus morhua , averaging 100 g, were experimentally challenged by intraperitoneal injection of nervous necrosis virus (NNV) originating from Atlantic halibut. Cod tissues, including blood, gill, pectoral fin, barbel, ventricle, atrium, spleen, liver, lateral line (including muscle tissue), eye (retina) and brain, were sampled at day 25 and 130 and investigated by real-time RT-PCR for the presence of NNV. Relative quantifications at day 130 were calculated using the 2−ΔΔCt method. Immunosuppression by injection of prednisolone-acetate was introduced for a 30-day period, and tissue sampled at day 180 and relative quantification estimated. No mortality or clinical signs of disease were observed in the challenged group. The challenge resulted in detection of NNV in blood, spleen, kidney, liver, heart atrium and heart ventricle at day 25, and by the end of the experiment NNV showed a clear increase in brain and retina, suggesting these to be the primary tissues for viral replication. There was no increase in the relative amount of NNV in blood, atrium, ventricle, spleen, liver and kidney. Corticosteroid implants resulted in a weak increase in virus RNA in spleen, kidney, liver and brain. These findings suggest that Atlantic cod is susceptible to infection with NNV from halibut. The observed tissue tropism patterns suggest an initial viraemic phase, followed by neurotrophy. Head-kidney is the best tissue identified for possible NNV detection by non-lethal biopsy, but detection was not possible in all injected fish. 相似文献
12.
An isolated, perfused gill pouch preparation and myography were used to determine responses of the branchial vasculature of a hagfish to the mammalian natriuretic peptides, rANP and CNP. In the isolated gill pouch preparation afferent perfusion pressures increased in the first 5 min of exposure to low concentrations (10–14 to 10–10M) of ANP and CNP and then decreased below starting values by 15 min. At higher concentrations the depressor response prevailed and natriuretic peptides switched the flow away from the efferent artery to the venous route, which would fill the peribranchial sinus in vivo. At low concentrations ANP increased circumferential tensions in afferent branchial arterial rings. At higher concentrations afferent and efferent branchial arteries relaxed in response to ANP and CNP. 相似文献
13.
How Zostera marina L. adapts to environmental stresses is of major interest to researchers wanting to obtain a better understanding of how to
preserve this ecologically important seagrass. We have examined the structure and chemical properties of the cuticle and epidermal
walls of Z. marina cotyledons at the pre-germination stage by microscopy, histochemistry, and chemical analyses. The epidermal cells, which
have a smooth plasma membrane and slight wall-ingrowth, are surrounded by thickened outer tangential walls consisting of cellulose
and pectic substances. The thick cuticle layer covers the outer surface of the outer tangential walls; the former were observed
here to be much thicker than has been reported earlier for the leaves and sheaths of Z. marina. Chemical analysis of the isolated cuticle by attenuated total reflectance–infrared Fourier transform spectrometry and gas
chromatography–mass spectrometry detected C16 and C18 fatty acids, ω-hydroxy fatty acids and β-sitosterol as components of the wax and cutin. The outermost cuticle layer was also
observed to be covered with a slimy layer consisting of some polysaccharides. These results suggest that the extremely thick
cuticle and slimy layer could play a significant role in protecting the cotyledons from environmental stresses at the pre-emergence
stage and just after emergence. 相似文献
14.
刀额新对虾 (Metapenaeusensis)采自福建沿海 ,体长约 14cm。活体解剖、取样、固定 ,于OlympusBH 2显微镜下观察 ,其生殖管道分为前输精管、中输精管、后输精管和端壶腹 4部分。前输精管上皮为单层柱状上皮 ,其分泌物呈嗜碱性 ;中输精管分泌物为嗜酸性 ,前段为高柱状上皮 ,后段则为柱状上皮 ,至后段共出现 2处上皮隆起 ,隆起间为扁平上皮 ;分泌管出现于中输精管前段 ,其分泌物呈嗜酸性 ,开口于中输精管后段 ,分泌物由此处流入中输精管腔 ;后输精管腔结构与中输精管腔相似 ,但管径缩小 ;端壶腹共分 3个腔 ,其中 2个由后输精管腔延续形成 ,精荚 1个。精荚由精子团和精荚壁组成。精荚壁分 2层 ,内层为均匀的嗜碱性初级精荚壁 ,精子团位于初级精荚壁中央 ;外层为次级精荚壁 ,呈嗜酸性 ,略呈“C”形包被于初级精荚壁之外。整个精荚横切面的外形似柳叶状 ,分为光滑区和皱折区 2部分 ,光滑区由次级精荚壁包被 ,皱褶区则为裸露的初级精荚壁。精荚形成于中输精管后段 ,它是由前输精管的嗜碱性分泌物、中输精管嗜酸性分泌物以及分泌管上皮细胞分泌物经复杂的化学变化形成 相似文献
15.
中国七种水生动物源无乳链球菌的分子特征及其对斑马鱼的致病性 总被引：1，自引：1，他引：0
为了解中国水生动物源无乳链球菌的分子流行特征,揭示其传播和流行规律,本实验对分离得到并鉴定的10株7种水生动物源无乳链球菌通过分子血清型、多位点序列分型(MLST)分型、毒力基因型和前噬菌体分型等方法进行分子分型;其次,通过斑马鱼评价7种水生动物源无乳链球菌的致病性。分子血清型分析结果表明,10株无乳链球菌可分为3种血清型,即Ⅰa、Ⅰb和Ⅲ型;MLST分型结果表明,Ⅰa型无乳链球菌均为ST7型,Ⅰb无乳链球菌均是ST261型,只有Ⅲ型无乳链球菌是ST739型。进一步分型结果表明,10株无乳链球菌可分为3种毒力基因型和4种前噬菌体基因型。根据4种分型结果可知,10株水生动物源无乳链球菌可分为4种类型,其中虎纹蛙源无乳链球菌具有独立的分子血清型、MLST型、毒力基因型和前噬菌体基因型,即Ⅲ-ST739-V1-P3;罗非鱼源无乳链球菌的基因型有3种,即Ⅰa-ST7-V2-P1、Ⅰa-ST7-V2-P2和Ⅰa-ST7-V3-P4;红尾皇冠鱼、鳙和罗非鱼源无乳链球菌的基因型相同:Ⅰa-ST7-V2-P2;卵形鲳鲹、宝石鲈和罗非鱼源无乳链球菌具有相同的基因型:Ⅰa-ST7-V2-P1;鲮和罗非鱼源无乳链球菌的基因型相同,即Ⅰb-ST261-V3-P4。致病性研究表明,7种水生动物源无乳链球菌对斑马鱼均有强致病性。研究表明,两栖类虎纹蛙源无乳链球菌和鱼源无乳链球菌的基因型明显不同,它们之间遗传变异较大,因此,无乳链球菌在两栖类和鱼类之间相互传播的可能性较小。鱼源无乳链球菌有3种基因型,且这3种基因型均在罗非鱼中流行,这表明无乳链球菌在鱼类中相互传播的可能性较大,尤其是在罗非鱼与其他鱼类之间。 相似文献
16.
应用石蜡切片及HE染色的方法对美洲鲥(Alosa sapidissima)早期发育过程中眼睛的发生、分化和形成过程进行了系统的观察.结果显示,受精后21 h 13 min,视泡出现;受精后26h 23 min,视泡发育成视杯;受精后35 h 44 min,原始视网膜和晶状体形成;受精后60h 15 min,角膜在视网膜前缘处形成,由单一的立方上皮构成;2日龄仔鱼,巩膜分化完成,由软骨组织和弹力纤维构成,脉络膜出现;3日龄仔鱼,虹膜出现,视网膜分化完全,由外向内的色素层、视觉细胞层、外界膜、外核层、外网膜层、内核层、内网膜层、视神经节细胞层、视神经纤维层和内界膜10层构成,此时视觉细胞层中视杆细胞出现;14日龄仔鱼,角膜分化完全,由自外向内的复层扁平上皮、前弹性层、基质层、后弹性层和内皮层5层构成;22日龄仔鱼,脉络膜腺出现;26日龄稚鱼脉络膜分化完全,由外向内依次为银膜层、血管层和色素层,虹膜也完全分化,由外向内依次为虹膜内皮层、前缘层、基质层、后缘层和色素层;45日龄幼鱼,视网膜内核层分化成两层水平细胞.此时美洲鲥眼睛的各个结构均发育完善. 相似文献
17.
Olli Arjamaa Olli Vuolteenaho Elina Kivi Mikko Nikinmaa 《Fish physiology and biochemistry》2014,40(1):67-73
Our aim was to study the effects of hypoxia on the release of salmon cardiac peptide (sCP) from an isolated heart ventricle of trout during a constant mechanical load. Trout heart ventricles were studied in vitro. The ventricle was placed in an organ bath at 12 °C in which a constant mechanical load could be imposed on the ventricle while buffer solution was circulating. Ventricles were field-stimulated with a supramaximal voltage pulse at a rate of about 0.3 s?1. Samples of 1 ml were collected at an interval of 10 min for 200 min from the organ bath and assessed with a radioimmunoassay for sCP. After a control period of 20 min, ventricles were exposed to hypoxia produced with N2 gassing (n = 9) or to hypoxia with 20 mM BDM, a nonselective myosin ATPase inhibitor locking cross-bridges in a pre-power-stroke state inhibiting force production with normal electrical activity (n = 10). In this model and setup, hypoxia stimulated the release of sCP, but the interindividual variation in the response was large. At the end of hypoxia exposure, the concentration of sCP in the organ bath was about sixfold higher than at the start of the exposure (P < 0.05, one-way ANOVA for repeated measurements, followed by Dunnett’s multiple comparison test). When BDM was introduced into the bath, the ventricle still secreted sCP but the hypoxic response was smaller than in the experiments without BDM. In the trout heart ventricle, there is a hypoxia-sensitive component in the release mechanism of sCP which is independent of contraction. 相似文献
18.
The structure of the chorion and plasma membranes of gastrula‐stage zebrafish Brachydanio rerio embryos were studied using field emission scanning electron microscopy (FE‐SEM) and transmission electron microscopy (TEM). These studies confirm the outer chorion membrane complex to be 1.5–2.5 μm in thickness and to consist of three layers, electron‐dense outer and innermost layers (0.2–0.3 and 1.0–1.6 μm in thickness respectively) separated by an electron‐lucent middle layer (0.3–0.6 μm in thickness). The middle and inner layers are pierced by pore canals. A granular to farinaceous nature of the thin outer surface of the outer layer of the chorion has been revealed for the first time. The study provides original TEM images of the plasma membrane structures of gastrula‐stage embryos, and FE‐SEM and TEM images showing the plasma membrane to have three morpohologically distinct regions, being prominently ridged and folded at the surface of the blastoderm, smooth over the syncytial layer at the vegetal pole and with an intermediate region between the animal and vegetal pole where folding develops in advance of the expanding blastodermal disc of cells. FE‐SEM and TEM studies reveal details of the syncytial layer (1–4 μm thick) beneath the smooth plasma membrane at the vegetal pole, containing cytoplasmic organelles and small yolk globules. The significance of the structural detail shown in these studies is considered in the light of the difficulties experienced in cryopreservation of the embryo resulting from the inability of achieving cryoprotectant penetration of the yolk mass. 相似文献
19.
海蜇生殖腺的组织学及发育研究 总被引：3，自引：0，他引：3
在人工控制下，将海蜇的碟状幼体培养性成熟，对其生殖腺发育过程的组织学构造及精卵发生进行了系统的观察，阐明了生殖的起源与发生过程，结果表明：伞径为１３０～１５０ｍｍ时，生殖腺开始发生，最初在紧靠胃丝外侧的中胶层出现细胞聚集，进而形成原始的胚原基础细胞，系由胃内胚层迁移而来，进一步的分化，使生殖腺形成，纤毛内胚层，中胶层，生殖上皮，生殖腔腺，生殖腔腺下伞面上皮，薄的中胶层，外胚层。 相似文献