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1.
香鱼消化道及肝脏的形态结构特征   总被引:2,自引:0,他引:2  
采用解剖及石蜡切片显微技术观察了香鱼消化道及肝脏的组织学结构。香鱼消化道由口咽腔、食道、胃及肠构成。口咽腔大且狭长,其底壁前部有一对粘膜褶,两颌边缘着生宽扁梳状齿,腭骨及舌骨具齿,犁骨无齿;舌由基舌骨突出部分覆盖粘膜构成,舌粘膜上皮为复层扁平上皮,含有较多的杯状细胞和味蕾。食道、胃及肠均由粘膜层、粘膜下层、肌层及外膜构成。食道粘膜层上皮为复层扁平上皮,杯状细胞发达。胃呈V形,由贲门部、胃体部及幽门部组成,胃壁粘膜上皮为单层柱状上皮,贲门部与胃体部的固有层中有胃腺。肠较短,由前、中、后肠构成,肠壁粘膜上皮为单层柱状上皮,其游离面具微绒毛;上皮细胞间有杯状细胞。幽门盲囊有350~400条,其组织学结构与肠相同。肝脏单叶,外被浆膜;肝细胞形态不规则,肝小叶界限不明显。  相似文献   

2.
Elasmobranchii shows particular characteristics that make them susceptible to the impacts caused by fishing pressure, especially bottom trawling, which mostly affect rays, as they have demersal habits. Based on food availability and feeding ability, Polychaeta and Sipunculiforme are the bases of Brazilian electric ray Narcine brasiliensis diet. Morphologically, the digestion starts in the oesophagus with acid mucines action. The existence of acid and neutral mucines in the posterior intestine prevents lesions in the mucosa and favours the passage of faeces and shell residues. Thus, this study shows the interaction between their habitat, the organisms and their morphophysiology.  相似文献   

3.
In amphioxus (Branchiostoma belcheri), calcitonin‐immunoreactive cells of the digestive tract were distributed concentrically in a 1‐mm region of the latter half of the mid‐gut. In the mid‐gut caecum these cells were also present, but were dispersed throughout the length. The total number of cells in both parts ranged from 280 to 1157, varying from individual to individual, although the number in the mid‐gut caecum was only 100–200. These cells were morphologically typical gut endocrine cells. Considering their morphology and the characteristics of their distribution pattern, these cells may be related to some phenomena of digestive processes.  相似文献   

4.
5.
This study reports a detailed anatomical and histological study of the digestive system of Octopus vulgaris. Emphasis was placed on characterising the glands and glandular cells and their distribution throughout the digestive tract. The use of classic histological and histochemical techniques revealed two morphological types of glandular cells: granular and mucous. Moreover, the histochemical analysis indicated specialisation of mucous glandular cells in the buccal mass, the submandibular gland and the caecum for secreting acid and neutral glycoconjugates. The cells of the anterior salivary glands are specialised for secreting neutral glycoproteins, and those of the posterior salivary glands are specialised for granular and mucous secretion. The oesophagus, crop and stomach lack glandular cells, but both granular and mucous glandular cells are found in the intestine. An unusual structure resembling the typhlosole of bivalves is described for the first time in the intestine of O. vulgaris. The highly ciliated epithelium and location of the structure in the anterior part of the intestine suggest a possible role in bypassing the caecum, stomach and intestine. We discuss how these cells and organs contribute to the process of digestion in the light of the present histological and histochemical data and of previously published information on the morphology and physiology of digestion in the octopus.  相似文献   

6.
The lifespan of herbivorous Rana pipiens larvae is ~3 months, while that of carnivorous Ceratophrys ornata larvae is only about 2 weeks. During metamorphic climax, the larval gut shortens dramatically, especially in R. pipiens, and its luminal epithelium is replaced by adult‐type epithelium. To determine when programmed cell death occurs during the metamorphic restructuring of the gut, we prepared cross‐sections of the stomach, small intestine, and large intestine from representative larval stages and from juvenile frogs of both species. The sections were incubated with monoclonal antibody against active caspase‐3, one of the key enzymes in the apoptotic cascade. We observed apoptosis in some luminal epithelial cells in each of the three regions of the larval gastrointestinal tract of both species. However, apoptotic cells appeared earlier in larval stages of R. pipiens than C. ornata and few were seen in juvenile frogs of either species. The results demonstrate the occurrence of apoptosis in the metamorphic remodeling of the gut of both R. pipiens larvae and C. ornata larvae. J. Morphol., 2011. © 2011 Wiley Periodicals, Inc.  相似文献   

7.
鳜鱼消化道黏液细胞和6种酶的组织化学定位   总被引:1,自引:0,他引:1  
采用阿利新蓝-过碘酸雪夫氏(AB-PAS)染色和酶组织化学方法对鳜鱼消化道各部位黏液细胞和6种酶的分布与定位进行了研究。结果显示,黏液细胞可为分为4种类型,食道黏液细胞多数为Ⅲ型和Ⅳ型,未见Ⅰ型和Ⅱ型;胃贲门和胃幽门黏膜上皮仅有Ⅰ型黏液细胞;胃体黏膜上皮则以Ⅲ型细胞为主;幽门盲囊中主要为Ⅱ型细胞;前肠和中肠中Ⅳ型黏液细胞最多,Ⅰ型最少;后肠黏液细胞则以Ⅳ型和Ⅱ型为主。酸性磷酸酶(ACP)主要分布于幽门盲囊和前肠的黏膜上皮;碱性磷酸酶(ALP)主要分布于食道、幽门盲囊和整个肠道黏膜上皮;非特异性酯酶(NSE)主要分布于胃幽门、中肠和后肠黏膜上皮;过氧化物酶(POX)在胃幽门黏膜上皮中活性较高;琥珀酸脱氢酶(SDH)主要分布于胃腺中;腺苷三磷酸酶(ATPase)在消化道各部位均有较多分布。鳜鱼消化道黏液细胞和酶的分布型与其它动物有相似之处,也有其一定的特异性,与消化道不同部位的消化吸收机能相适应。  相似文献   

8.
At hatching, the yolk-sac matrix of Siberian sturgeon Acipenser baeri contained neutral glycoconjugates, glycogen, proteins rich in arginine, lysine, tyrosine, cysteine and cystine, glycoproteins containing mannose (Man) and/or glucose (Glc), N -acetyl-D-galactosamine (GalNAc), L-fucose (Fuc), sialic acid and/or N -acetyl-D-glucosamine (GlcNAc) residues, as well as neutral and acidic lipids. Buccopharyngeal and anterior oesophageal goblet cellls produced a combination of neutral and acid sialoglycoproteins, while those from the posterior oesophagus secreted only neutral glycoproteins; both types of secretions contained tryptophan and -S-S- groups and were unreactive to lectin techniques. Most intestinal goblet cells secreted mainly carboxylated and sulphated sialoglycoproteins with some rests of neutral glycoconjugates, while few of them produced only acid or neutral glycoproteins. Intestinal glycoproteins were rich in GalNAc, GlcNAc and sialic acid residues. Close relationships between digestive enzymes and morphological development of digestive organs were observed. Histochemistry of enzymes revealed that just after hatching, alkaline and acid phosphatase, ATP -ase and non-specific esterase activities were detected in the yolk sac. From the onset of exogenous feeding to the juvenile stage (30 days post-hatch), an enhancement of enzymatic activities was observed, as alkaline and acid phosphatase, ATP -ase, aminopeptidase M and nonspecific esterase sharply increased. However, lipase activity decreased in the liver and brush border of enterocytes by 13–14 days post-hatch. Two types of lipase were detected in the alimentary canal, a non-pancreatic lipase that was secreted in the cardiac stomach by gastric glands, and a pancreatic lipase, which activity was mainly detected in the brush border of the intestinal epithelium.  相似文献   

9.
The histological development and mucous histochemistry of the alimentary tract in larval yellowtail flounder were studied using light microscopy. Samples were taken when the larvae were first offered food at 3 days post-hatch, then at 7, 10, 29, 36, and 46 days post-hatch, at which time they were metamorphosing. Regional partitioning of the digestive tract into the buccal cavity, pharynx, oesophagus, post-oesophageal swelling (PES), intestine, and rectum was complete by day 10. Goblet cells were present only in the buccal cavity, pharynx and intestine by day 7, but increased in number and distribution as development continued. By day 29, the posterior zone of the oesophagus had a marked increase in goblet cell density and mucosal folding. At the transition from oesophagus to PES/stomach stratified epithelium with goblet cells changed abruptly to a columnar epithelium with no goblet cells. Multicellular glands in the PES of 36-day larvae allowed it to be defined as a stomach. The distinct brush border of columnar epithelium and the presence of goblet cells characterize the intestine and rectum. All goblet cells throughout the digestive tract were strongly positive for acid mucins as was the luminal layer of the stratified epithelia lining the buccal cavity, pharynx and oesophagus. The PES/stomach epithelium stained weakly for neutral mucins. No mucin staining was associated with the gastric glandular epithelium. The brush borders of the intestine and rectum were strongly positive for combinations of neutral and acid mucins.  相似文献   

10.
and 1992. Ultrastructure and histochemistry of the digestive tract of juvenile Paramphistomum epiclitum (Paramphistomidae: Digenea) during migration in Indian ruminants. International Journal for Parasitology 22: 1089–1101. The digestive tract of juvenile Paramphistomum epiclitum consists of a foregut with a highly muscular terminal pharynx and an oesophagus, which leads to a pair of unbranched and blind-ending intestinal caeca. A syncytium lining the foregut is continuous with the external tegument and displays similar sensory papillae and secretory bodies (T1 and T2). A third type of secretory body (T3) is confined to the oesophageal cytons of newly excysted juveniles and is first evident in the syncytium by day 14 of migration. An epithelium lining the caeca is composed of a single layer of morphologically uniform cells whose apical surface is amplified by microvilli. Dense secretions synthesized in the caecal epithelium of mature cercariae are released during migration by a mechanism resembling modified apocrine discharge. The caecal epithelium of migrating juveniles undergoes a 10-fold increase in surface amplification (irrespective of growth) during its transition from a primarily secretory tissue to one apparently specialized for absorption.  相似文献   

11.
为探讨农药马拉硫磷对东亚飞蝗Locusta migratioria manilensis(Meyen)消化系统的影响,文中以喂食形式给药,不同喂食时间点蝗虫处死后固定、石蜡包埋、连续切片、HE染色并观察蝗虫消化系统不同部位形态学的病理变化。结果表明马拉硫磷对东亚飞蝗嗉囊、前胃、胃盲囊、中肠、回肠、结肠、直肠等各消化道部位均能造成明显的形态学改变,包括内膜完整性被破坏、上皮细胞死亡、纵肌、环肌、结缔组织等病变和坏死等,且呈时间依赖性。故马拉硫磷的作用可以影响到东亚飞蝗对食物贮存、研磨、消化、养分吸收的每一个环节,最终导致蝗虫的死亡。本文研究结果对蝗虫防治研究具有重要意义。  相似文献   

12.
The gross anatomy and microanatomy of the digestive system of Ichthyophis supachaii were investigated. The microscopic structures of the digestive system are similar to those in other caecilians. Functional and developing teeth are present in adults. The tongue contains the genioglossus muscle. The digestive tract is elongated and consists of the mucosa, submucosa, muscularis and adventitia/serosa. The oesophagus contains longitudinal folds and lacks oesophageal glands. We report for the first time the caecilian gastric rugae and specific localization of oxynticopeptic cells in the anterior gastric region. The intestinal folds are exclusively present in the anterior intestinal region. The liver comprises 30–40 incomplete hepatic lobes, lying in an imbricate manner. Each lobe is enveloped by haematopoietic tissue that produces and delivers blood cells into sinusoids. Hepatic parenchyma is organized into anastomosing, two‐cell‐thick plates, having sinusoids at the basal domain and bile canaliculi at the apical domain of hepatocytes. Pigment cells are scattered inside sinusoids. The pancreas contains pancreatic acini interspersed with islets of Langerhans. The gallbladder proper is thin and continuous with the cystic duct wall. Neutral and carboxylated acid mucosubstances are secreted along the digestive tract, while sulphated mucosubstances are not produced by the stomach and anterior intestinal regions.  相似文献   

13.
粉尘螨消化系统的形态学观察   总被引:1,自引:0,他引:1  
光镜下观察了粉尘螨Dermatophagoides farinae消化系统结构,其组成包括:口前腔、前肠、中肠、后肠、肛门和唾液腺。口前腔由颚体围绕而成;前肠包括一个肌肉的咽和食道,食道从脑中穿过;中肠分为前中肠(包括一对盲肠)和后中肠,中肠的上皮细胞呈现多种形态; 后肠包括相对大的结肠和狭窄的直肠;消化腺为不规则形,位于脑前方。本文阐述了消化道的分支情况、显微结构及细胞形态。  相似文献   

14.
中华稻蝗消化道内分泌细胞的鉴别与定位   总被引:1,自引:0,他引:1  
采用整块组织Grimelius银染法和过氧化物酶标记的链霉亲和素免疫组织化学技术,结合生物统计学分析,对中华稻蝗Oxya chinensis消化道内分泌细胞进行鉴别与定位。结果表明:嗜银细胞分布于中华稻蝗的胃盲囊、中肠和后肠各段,以中肠和直肠中最多(P<0.05), 前肠中未见分布。免疫组织化学法检测出了五羟色胺(5-hydroxytryptamine, 5-HT)、 胃泌素(gastrin, Gas)、 胰高血糖素(glucagon, Glu)和胰多肽(pancreatic polypeptide, PP)细胞, 未检出生长抑素(somatostatin, SS)细胞。免疫阳性细胞分布于中肠和后肠中, 前肠中未见分布。5-HT细胞和Gas细胞均主要分布于胃盲囊、中肠及直肠中,且均以直肠中最多(P<0.05)。Glu细胞在胃盲囊及整个中、后肠均有分布, 在中肠和直肠中最多(P<0.05)。PP细胞主要分布于中肠、回肠和直肠中,中肠中分布密度最大(P<0.05)。本研究显示中华稻蝗消化道中存在多种内分泌细胞,它们的分布情况与其他节肢动物相比存在一定的共性,也有其一定的特异性,可能与中华稻蝗特定的消化道结构和消化生理功能有关。  相似文献   

15.
The aim of this study is to explore the morphology and histochemistry of the digestive tract of Acipenser dabryanus (Duméril, 1869). The digestive system of the Dabry's sturgeon contained an oropharyngeal cavity, esophagus, stomach, pyloric caeca, duodenum, valvula intestine, and rectum. Both the pyloric caeca, and the valvula intestine, which belonged to elasmobranch, were present simultaneously in the digestive system of the Dabry's sturgeon, which indicated that it was an archaic species. According to the results, we found four types of mucous cells exist in the digestive tracts of the Dabry's sturgeon. The statistical results showed that there were various types and densities of mucous cells in different parts. In comparison, large quantities of mucous cells existed in intestines. The difference in type and distribution of mucous cells are closely related to the functions of the organs where they are found; 5‐hydroxytryptamine were used to identify the endocrine cells in the digestive tract of the Dabry's sturgeon.The 5‐hydroxytryptamine immunoreactive cells were distributed throughout the digestive tract except the esophagus.  相似文献   

16.
运用解剖学和组织学方法对宽体金线蛭消化道的结构进行了组织学研究。结果表明,宽体金线蛭的嗉囊向两侧伸出11对侧盲囊,第6对侧盲囊狭长并延伸到直肠两侧;咽主要由黏膜层、肌层和外膜构成,外膜几乎不可见;食道、嗉囊、肠和直肠管壁由黏膜层、黏膜下层、肌层和浆膜构成;咽和直肠的上皮具纹状缘。除肠外,其他消化道的上皮细胞均无发达的纤毛,且黏膜上皮皆为单层柱状上皮;除肠和直肠外,腺体及导管较少;直肠的黏膜肌层为内环外纵两层,其他各部均为纵行肌一层;消化道各部黏膜下层较发达;外膜为浆膜,与黏膜下层分界不明显。  相似文献   

17.
Various studies address the morphology of the gastrointestinal tracts (GITs) of insectivorous bat species. However, detailed morphometric studies including mucin histochemistry are scarce. This study compares various GIT measurements as well as the quantification of intestinal mucin secreting cells in four insectivorous bat species representing four different families of Chiroptera. Alcian blue/Periodic acid Schiff's stain was used to differentiate between acid and neutral mucin-secreting cells while the Aldehyde fuchsin/Alcian blue stain further differentiated between two acid mucins, namely sialo-, and sulphomucins. The number of cells was quantified and statistically analysed. All species had a simple GIT morphology represented by a simple, completely glandular stomach and the absence of a cecum. The exception was R. hardwickii, where a small cecum was observed which had histological mucosal features of both the small and large intestine. In R.hardwickii, distal to the cecum, typical colonic mucosal features such as the absence of villi and an abundance of goblet cells were observed. In all four species, the total number of goblet cells increased from the proximal to the distal intestinal regions. Mixed (acid and neutral) mucins dominated the entire GIT of all species. Neutral mucin-secreting cells were observed in the gastric pylorus and proximal intestinal regions in all species. Brunner's glands stained positive for neutral mucins. Exclusively acid mucin-secreting cells were seen in the distal intestinal regions of all species except N. thebaica. Sulphomucin-secreting cells were the most prominent acid mucin cell-type towards the distal intestine. The distribution of different mucin secreting cells indirectly provides information regarding the quality of the intestinal biofilm in the species studied.  相似文献   

18.
A study of the histology of the digestive tract of the Nile tilapia   总被引:8,自引:0,他引:8  
The digestive tract of Oreochromis niloticus is described, in order to resolve discrepancies found between previous accounts. Two types of goblet cells were found in the oesophagus, which differed in size, and in staining characteristics with periodic acid-Schiff and alcian blue. A region with tubular glands consisting of large mucous cells was continuous from the entry of the oesophagus, across the anterior part of the stomach to the pyloric valve, essentially providing a bypass circumventing the sac-like portion of the stomach. This region, which is lined with striated muscle, may be a means of disposing of unwanted material, either by regurgitating it, or by passing it rapidly along to the intestine. Large mucus cells in the tubular glands and the neck cells of the gastric glands probably protect the mucosa from the very acid contents of the stomach. An ileorectal valve was present. There is therefore a separate intestine and rectum in O. niloticus , as in most teleosts.  相似文献   

19.
消化系统真菌感染是指真菌感染食管、胃肠、肝胆、胰或消化系统的其他组织或器官,该文对消化系统真菌感染的病原菌、临床表现、病理特征和治疗措施进行综述。  相似文献   

20.
采用解剖及石蜡切片显微技术,观察研究了光唇鱼消化道的形态结构特征。消化道由口咽腔、食道、肠构成。口下位、马蹄形,无颌齿,具咽齿,齿式为4/4。舌较小,前端游离,舌粘膜表层为复层鳞状上皮,有较多的杯状细胞和味蕾。食道及肠均由粘膜层、粘膜下层、肌层及外膜构成。食道内皱襞发达,粘膜层有大量杯状细胞。肠道盘曲,由前、中、后肠组成,肠长/体长为1.84±0.24;前肠管腔较大,中、后肠管腔渐变小;前、中肠皱襞及纹状缘比后肠发达;前肠及后肠杯状细胞较少,中肠杯状细胞较多。光唇鱼消化道的形态结构特征与其食性相适应。  相似文献   

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