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许氏平鮋消化道中部分消化酶的研究 总被引:1,自引:0,他引:1
对许氏平 (Sebastesschlegeli)消化道内的 5种与消化吸收有关的酶进行分布和活性测定。结果表明 ,(1)肠道各段均具很高碱性磷酸酶活性 ,最适 pH为 9.7。食道和胃几乎没有碱性磷酸酶活性。 (2 )消化道各部位均含酸性磷酸酶 ,肠道活性最高 ,自幽门盲囊起依次递降。食道和胃酸性磷酸酶活性明显低于肠 ,胃和肠酸性磷酸酶的最适 pH均为 5 .3。 (3)肠道中羧酸酯酶活性明显高于胃 ,且 2者羧酸酯酶最适 pH差别较大 ,分别为 8.4和 6 .8。(4)胃蛋白酶活性明显高于肠道 ,胃蛋白酶最适pH为 2 .6 ,肠蛋白酶最适 pH为 9.4。 (5 )胃淀粉酶活性明显低于肠道 ,胃淀粉酶最适 pH为 4 .6 ,肠道淀粉酶最适pH为 7.0。这表明许氏平对蛋白质的初步消化在胃中进行 ,在肠中进一步消化和吸收 ,而对糖类和脂类的消化和吸收主要在肠道进行 相似文献
64.
采用显微解剖和测量、光镜和扫描电镜观察方法,系统观测全长为5.6~330.0mm的青鱼标本370尾,描述了鳃耙、咽齿、角质垫和肠等消化器官数量性状在胚后发育过程中的变化规律;论述了青鱼的摄食特性、消化器官数量性状胚后发育的阶段性及其相关性、消化器官数量性状发育与食性转化,为制订培育青鱼苗种和饲养成鱼的生物学技术提供了可靠依据 相似文献
65.
N. Arcamone L. D’Angelo P. de Girolamo C. Lucini A. Pelagalli L. Castaldo 《Research in veterinary science》2014
This study reports the immunohistochemical localization and distribution of orexin A and B-like and their receptors-like peptides in the gastroenteric tract of chicken. The immunoreactivity is distributed in endocrine cells, nerve fibers and neurons, both in the stomach and intestine, and shows a discrete conformity with the data till now reported for Mammals. Our study suggests a possible participation of orexin-like peptides in the modulation of chicken gastroenteric activities and the preservation of their main distribution compared to Mammals. Western blot analysis has confirmed the presence of prepro-orexin and both receptors in the examined tissues. 相似文献
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目的评价1例全骨盆以下离断伤消化道重建术患者远期生活质量。方法 1例全骨盆以下离断伤患者行消化道重建术,术中保留右半结肠,行横结肠造瘘建立人工肛门。术后1、2、3个月及1、2、3、5、9 a记录14项消化道重建术后随访内容,采用3级评分标准。结果患者住院616 d,借助下肢康复材料生活基本自理。术后6个月时饮食类型、饮食量、进食时间、饭后腹胀、烧心感、失眠、体质量减轻、吞咽困难、呕吐和头晕项均达3分,术后2 a起患者消化道重建术后随访内容的评分为42分,达正常成人水平。结论全骨盆离断伤后消化道重建可为患者的长期生存提供保障。 相似文献
68.
采用大体解剖和光镜技术研究了海鳗(Muraenesax cinereius)消化道形态学和组织学。海鳗消化道分化为明显的食道、胃和肠。食道皱襞多且粗大,黏膜为复层上皮,部分区域为单层柱状上皮。上皮中含两种类型的杯状细胞,以杯状细胞层次多为显著特征,此外还有嗜酸性细胞。肌层厚。浆膜中纤维发达,伸人肌层并与黏膜下层相连。胃“Y”形,分为贲门部、盲囊部和幽门部,盲囊部发达。胃上皮为单层柱状上皮,贲门部和盲囊部胃腺发达,至幽门部胃腺逐渐消失。肠短,由具微绒毛的单层柱状上皮构成,小肠前段绒毛分支多且相互吻合,毛细血管丰富,平滑肌多。直肠单层柱状上皮与假复层纤毛柱状上皮共存。海鳗消化道组织结构特点反映了其凶猛、食肉、食量大的食性特点。 相似文献
69.
A.G. Becker J.F. Gonçalves L.O. Garcia E.R. Behr F.J.K. Mallmann D.L. Graça B. Baldisserotto 《Fish physiology and biochemistry》2006,32(2):105-112
The levels of various ions (Na+, Cl−, Ca2+, Mg2+, K+) in the fluid phase of the gastrointestinal contents and of the plasma were determined in four teleosts with different feeding habits: traira (Hoplias malabaricus), hassar (Hoplosternum littorale), silver catfish (Rhamdia quelen), and grass carp (Ctenopharyngodon idella). The results showed that most ionic levels in the fluid phase of the gastrointestinal tract seem to be affected by feeding habit and that these levels can be different from those found in the plasma. In practical terms, these results suggest that ionic levels of the gastrointestinal contents should be considered when preparing solutions for studies of intestinal absorption in fishes. 相似文献
70.
Two carbohydrases (cellulase, lysozyme), three proteases (trypsin, aminopeptidase and non-specific protease), a non-specific lipase, and semiquantitative tests of 19 digestive enzymes were assayed in different gut sections of juvenile red abalone, Haliotis rufescens, in order to identify the regions where digestion takes place and investigate the extent to which diet composition can modify the digestive capacity of abalone. The abalone were fed either fresh kelp (K) or balanced diets containing 25 or 38% crude protein for 6 months. Enzyme assays were carried out on different sections of the abalone's gut at the end of this period. On a weight-specific basis, the digestive gland was the site containing most of the enzymes. On a protein-specific basis, two main digestion regions were identified: the digestive gland-stomach region that is characterized by high activities of cellulase and lysozyme, chymotrypsin and protease, and the mouth-intestine region with a typically high activity of lipase and amino peptidase. Significant dietary effects were observed on the activity of enzymes, especially in the digestive gland. Abalone fed with 25 and 38% crude protein diets exhibited higher cellulase (39.8 ± 4.6 and 14.2 ± 0.8 mU mg− 1 protein, respectively) and lysozyme activities (88.0 ± 20.4 and 56.6 ± 15.7 U, respectively) than those fed with fresh kelp (5.5 ± 0.7 mU mg− 1 protein and 17.1 ± 1.8 U). In contrast, higher protease activity was found in kelp-fed organisms (234.1 ± 20.4 μg product/mg protein) than those fed the 25 and 38% crude protein diets (109.5 ± 20.7 and 119.5 ± 20.5 μg product/mg protein, respectively). Semiquantitative API ZYM assays resulted in no clear food-specific effects on the activity of carbohydrases, proteases, ester hydrolases or phosphohydrolases, yet organ-specific differences were conspicuous in various cases, and generally agreed with quantitative results. It is suggested that the increased carbohydrase activity exhibited by organisms fed the balanced diets resulted from a combination of an increased number of resident bacteria in the abalone's gut and facilitated contact between dietary substrates and digestive cells. The present results indicate that H. rufescens can adjust their enzyme levels in order to maximize the acquisition of dietary protein and carbohydrates. This characteristic can be advantageously used to search for suitable diets in abalone aquaculture. 相似文献