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1.
A new tissue isolation technique was used to create intact midgut epithelial wholemounts from three Trichoplusia ni (Lepidoptera: Noctuidae) larval instars. The protease, dispase, removed the basal lamina and associated connective tissue and allowed for high resolution light microscopy of entire epithelia. Columnar, goblet, differentiating, and stem cells were characterized by double fluorescent labelling of f-actin and nuclei. A comparison of cell populations by digital image analysis revealed significant regional and temporal changes in the density and number of differentiating and stem cells. Growth of the midgut epithelium from third to fourth instar, and from fourth to fifth instar, was accomplished by both cell differentiation and cell division. Cell division however, was greatly reduced from fourth to fifth instar with a concomitant sharp decrease in the stem cell population.  相似文献   
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The larval midgut of the silkmoth Hyalophora cecropia was examined using scanning electron microscopy. Goblet cells were observed to contain within their cavities a matrix plug. This matrix material was extruded onto the lumen side of the epithelium when the tissue was stretched. The rôle of this matrix material in maintenance of the capacity of the midgut to transport ions in vivo and in vitro is discussed.  相似文献   
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The ingestion of Bacillus thuringiensis crystal endotoxin by Manduca sexta causes the destruction of both goblet and columnar cells of the midgut. One hour after ingestion, the microvilli show pathological effects. Nearly complete destruction of the goblet and columnar cells has taken place after 4 hr exposure to the toxin.  相似文献   
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This study aimed to evaluate the microbial compositions and gene expression related to inflammation in dextran sodium sulfate (DSS)-induced acute colitis and the effect of mulberry supplementation. Male BALB/c mice received a diet supplemented with mulberry juice freeze-dried powder (MFP) or not for 3 weeks. After 3 weeks, the mice received water containing 5% (w/v) DSS or not for 1 week. The disease activity index score in mice fed MFP was significantly decreased. A significant decrease in Bifidobacterium spp. and the Clostridium perfringens subgroup was observed in mice not fed MFP. The number of goblet cell and NLRP6 expression were observed in mice fed a diet supplemented with MFP compared with mice not fed MFP. These results may indicate that mulberry mitigates DSS-induced acute colitis by a changing the gut microbial flora and by improving mucosal conditions.  相似文献   
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The effects of anti-allergic drugs on intestinal mastocytosis and the expulsion of Neodiplostomum seoulense were observed in Sprague-Dawley rats, after oral infection with 500 metacercariae. The drugs used were hydroxyzine (a histamine receptor H1 blocker), cimetidine (a H2 blocker), cyclosporin-A (a helper T-cell suppressant), and prednisolone (a T- and B-cell suppressant). Infected, but untreated controls, and uninfected controls, were prepared. Worm recovery rate and intestinal mastocytosis were measured on weeks 1, 2, 3, 5, and 7 post-infection. Compared with the infected controls, worm expulsion was significantly (P < 0.05) delayed in hydroxyzine- and cimetidine-treated rats, despite mastocytosis being equally marked in the duodenum of all three groups. In the cyclosporin-A- and prednisolone-treated groups, mastocytosis was suppressed, but worm expulsion was only slightly delayed, without statistical significance. Our results suggest that binding of histamine to its receptors on intestinal smooth muscles is more important in terms of the expulsion of N. seoulense from rats than the levels of histamine alone, or mastocytosis.  相似文献   
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A reduction of epidermal club cells and an increase of goblet cells were found in Carassius gibelio during spawning when compared to postspawning. A significantly lower proportion of club cells at spawning was found in diploid males and triploid females than in diploid females. It could be linked to male efforts to avoid a fright reaction and the potential adoption of this strategy by gynogenetic females, or alternatively to a higher parasite infection or immunosuppression during spawning.  相似文献   
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南方鲇消化道杯状细胞分布及类型探讨   总被引:13,自引:0,他引:13  
本研究应用阿利新蓝-过碘酸雪夫氏(AB-PAS)染色方法对南方鲇(Silurus meridionalis)消化道杯状细胞的分布特点进行了分类研究,结果表明:南方鲇消化道杯状细胞的数量从肠前段、肠中段到肠后段,呈现递增趋势,有杯状、囊状和梨形三种不同的形态,AB反应阳性,PAS反应阴性,分泌物主要含酸性粘多糖,属Ⅱ型粘液细胞。  相似文献   
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目的:探讨干预气道杯状细胞CLCA的表达与功能,对ARDS小鼠肺脏损伤程度的影响,并通过体外细胞研究探讨其机制。方法:制备LPS诱导的ARDS小鼠模型(ARDS组),并在此模型上分别进行干预,包括气道雾化吸入CLCA非特异性阻断剂尼氟灭酸(NFA)(NFA+ARDS组)、气道滴注CLCA特异性抗体(ab-CLCA3)(ab-CLCA3+ARDS组)。HE染色观察各组小鼠肺部病理及炎症特征,计算肺损伤评分。运用hCLCA1-siRNA抑制人正常支气管上皮细胞系16HBE中h CLCA1的表达,采用real-time RT-PCR法验证抑制效果后,检测各组细胞合成多种炎症因子m RNA水平的差异。结果:HE染色显示,ARDS组与NFA+ARDS组相比,肺部病理改变及炎症细胞浸润程度无明显差异,肺损伤评分也没有统计学差异(正常组:2.0±0.71;ARDS组:6.8±0.45,NFA+ARDS组7.4±0.89,P0.05)。与ARDS组相比,ab-CLCA3+ARDS组肺部病理损伤及炎症细胞浸润程度明显加重,肺损伤评分也升高(正常组:1.8±0.83;ARDS组:7.6±0.55,ab-mCLCA3+ARDS组9.8±0.83,P0.05)。real-time RT-PCR检测证实成功构建hCLCA1低表达的16HBE细胞系,同时real-time RT-PCR结果显示TNF-α和IL-1β的m RNA表达水平升高(P0.05)。结论:阻断气道CLCA功能区域,可以加重ARDS小鼠肺部病理损伤程度及炎症细胞浸润水平,提示气道杯状细胞CLCA在ARDS小鼠肺部炎症形成过程中发挥抑制性调节作用。  相似文献   
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