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231.
Summary Somatostatin-immunoreactive nerves and endocrine cells were localized by use of immunohistochemistry in human stomach, small and large intestine. The nature of the immunoreactivity in acid extracts of separated layers of intestine was determined with separation by high pressure liquid chromatography followed by detection with radioimmunoassay; authentic somatostatin-14 was found in the external musculature, which contains nerves, and in the submucosa and mucosa, which contain both nerve fibres and endocrine cells.The distribution of somatostatin nerves in the gastric antrum, duodenum, jejunum, ileum, ascending and sigmoid colon, and rectum is described. In the intestine many positive perikarya and fine varicose fibres were seen. Mucosal fibres formed a sub-epithelial plexus and a looser network in the lamina propria; this nerve supply was less dense in the large intestine. Submucous ganglia contained positive perikarya and terminals; many terminals formed pericellular baskets, mainly around non-reactive cells. A small number of nerve fibres were associated with submucosal blood vessels. The innervation of the circular and longitudinal muscle was sparse. Positive nerve terminals were seen in the myenteric plexus, although fewer than in the submucous ganglia; positive perikarya were scarce in myenteric ganglia. Somatostatin-immunoreactive nerves were found in the muscle layers and myenteric plexus of the gastric antrum, but were not detected in the antral mucosa and all layers of the gastric body.The distribution of human enteric somatostatin nerves is compared to that in small laboratory animals, and possible roles for these nerves are discussed.  相似文献   
232.
Summary The avian stomach is subdivided into two parts, the proventriculus and the gizzard. It has been shown that the gizzard epithelium can express embryonic chick pepsinogen (ECPg) antigen, a marker protein of the proventricular epithelium, as well as normal proventricular epithelium, under the appropriate experimental conditions. To study the possible mechanisms involved in the suppression of ECPg synthesis in the gizzard epithelium during normal development, we carried out heterotypic and heterochronic recombination experiments of the epithelium and mesenchyme of these two organ rudiments. When recombined and cultured with 6-day proventricular mesenchyme, gizzard epithelium of 3.5- to 12-day embryos expressed pepsinogen at all stages tested. However, the ratio of ECPg-positive cells to total epithelial cells in the gizzard epithelium decreased rapidly when epithelium older than 7 days was cultured with proventricular mesenchyme. In contrast to proventricular mesenchyme, 6-day gizzard mesenchyme did not allow ECPg expression in associated proventricular epithelium of 3.5- to 7-day embryos. These results indicate that gizzard epithelium does not express pepsinogen in normal development because of both a decrease in ability to express the enzyme in itself in the course of development and a repressive influence of gizzard mesenchyme.  相似文献   
233.
Summary The ultrastructure of endocrine-like cells of the human lung was compared to the ultrastructure of endocrine-like cells of the stomach and pancreas in both adult and foetal material.Three types of endocrine-like cells were found in the human foetal lung. Type 1 or P1 cells contained very small granules (about 110 nm) of two varieties, cored and vesicular; type 2 or P2 cells with cored granules measuring about 130 nm; and type 3 cells with cored granules of about 180–190 nm. In the adult lung only one type Pa cells with cored granules could be found.Cells resembling foetal P1 cells were not found in foetal or adult gastric mucosa, or in the pancreas. In the gastric mucosa cells resembling pulmonary Pa or P2 cells were moderately represented and often difficult to distinguish from each other. Thus, they were grouped together as gastric P cells. Cells with granules resembling those of pulmonary type 3 cells were found most numerous in the adult oxyntic mucosa. Cells resembling gastric P cells (and pulmonary P2 cells) were rather numerous in foetal pancreas, but very rare in adult pancreas. Few cells containing granules somewhat resembling those of pulmonary type 3 cells were present in both foetal and adult pancreas.The results were discussed in respect to 1) the similarities between some gastric or pancreatic carcinoids and lung carcinoids, 2) the gastro-pancreatic P cells as a separate cell population, 3) the possible secretion by the lung endocrine-like cells of active substances, either amines or peptides, 4) the similarity between the secretory granules of Pa and P1 cells and neurosecretory granules of the hypothalamus and between P2 cells and some endocrine cells of the pituitary.Supported in part by the Italian National Research Council (Grants N. 75.00630.04 and N. 76.01558.04)  相似文献   
234.
235.
Conditions in vitro producing high rates of evagination of the cysticercus of Taenia hydatigena were obtained with an enzyme mixture of either 100 nig trypsin or 100 mg pancreatin and 5 ml whole dog bile made up to 100 ml with Hanks' balanced salt solution (BSS). Single enzyme solutions, or whole bile, in Hanks' BSS were not efficient. A pretreatment with an acid pepsin solution had little effect, on the rate of evagination. Evagination in vivo took place in the small intestine where a large portion of the larval tissue was shed almost immediately. There was no significant relationship between the mean weight of cysticerci fed to dogs AND the mean weight of scoleces recovered after 24 hr or 20 days.  相似文献   
236.
We found an association between tonsillectomized patients and subsequent appendicitis. We also observed that MALTectomy significantly decreased secretory IgA levels in serum of patients, being this decrease more pronounced when both operations (tonsillectomy and appendectomy) had been performed. The elevated humoral responses detected previously by us in BALB/c mice immunized with Kudoa sp. pseudocyst extracts and the high IgG1 and IgE levels induced by the oral administration of Kudoa sp. pseudocysts to BALB/c mice showed the possible immunopathological effects in man from the ingestion of Kudoa sp. infected fish. We use the ELISA method to investigate the possible relationship between MALTectomy (tonsillectomy and appendectomy) and specific antibody levels to Kudoa sp. Both anti-Kudoa sp. specific antibody levels and the number of patients that recognized Kudoa sp. antigens were greater in tonsillectomy patients when compared to the control and the other studied groups (appendectomized and appendectomized + tonsillectomies patients). Tonsillectomy was associated to a switch in the class of immunoglobulins involved in these responses and these responses may be abrogated by appendectomy. Tonsils and appendix may respond in different ways to Kudoa sp. antigens and these different reactions may be involved in some immunopathological reactions.  相似文献   
237.
前期研究证实在凝胶堵塞循经络的低流阻通道能够降低小型猪模型的痛阈,并引起一系列的行为异常、证候、内脏剖检等变化,本文对这些变化开展了病理学研究。将小型猪随机分为胃经不通组(SBG, n=8)、肾经不通组(KBG, n=8)和对照组(CG, n=6)。用凝胶注射法分别堵塞胃经和肾经低流阻通道,饲养7-9周,观察相关指标。血液肌酐检测结果显示,三组造模后均有增长,但KBG显著低于SBG(13.76%,p<0.05)和CG(14.51%,p<0.01)。脏器切片显示,CG的心脏、SBG的肝脏及KBG的肾脏和睾丸半数以上显示异常。肠切片显示,SBG十二指肠隐窝深度、结肠黏膜及大肠黏膜总厚度较对照组显著增加,空肠V/C值和回肠隐窝深度较KBG显著减小,回肠V/C值较KBG极显著增加。与对照组比较,KBG十二指肠隐窝深度和结肠黏膜厚度极显著增加。回肠隐窝深度较SBG极显著增加,胃泌素阳性面密度极显著高于其他两组。以上结果表明,堵塞胃经或肾经的低流阻通道可以出现不同的病理变化,为进一步研究经脉不通导致的病候群提供科学依据。  相似文献   
238.
目的:探讨针刺疗法对胃肠实热型单纯性肥胖症的治疗效果。方法:纳入近5年新加坡广惠肇留医院中医门诊中心符合胃肠实热型单纯性肥胖症标准的病例共67例,遵循中医"辨证施治"原则制定治疗方案,采用腹部围针法加体针进行治疗,每周治疗两次,10次为一个疗程,共治疗三个疗程,观察三个疗程针刺对单纯性肥胖症(胃肠实热型)体重及体重指数(BMI)的影响。结果:(1)男女两组患者BMI分布明显不同,超重和1度肥胖的女性患者明显多于男性,有显著性差异(P<0.05);(2)单纯性肥胖病患者经针刺治疗三个疗程后,治愈率68.7%,显效率23.9%,总有效率92.6%;患者体重显著降低(P<0.01),且两个疗程显著优于l疗程(P<0.01),三个疗程疗效显著优于两个疗程(P<0.01)。结论:针灸可明显降低体重及体重指数(BMI),且辨证论治是提高针刺疗效的关键环节,同时治疗时间越长,效果越显著。  相似文献   
239.
A monoclonal antibody, CP11, has been produced which is directed against the ureas of Campylobacter pylori. This antibody has been used to look for antigenic cross-reactivity, in other ureolytic and non-ureolytic campylobacters, by immunohistological techniques. It has also been used to investigate the helical-shaped organisms found in the stomach of the human, monkey and cat (CS1) and the ileum of the rat (ST1). Interestingly the antibody cross-reacted with the gastric helical organisms from the human, monkey and cat but not with the rat helical organism. No cross-reactivity was observed with C. mustelae or the other ureolytic campylobacters, C. nitrofigilis and the urease positive thermophilic campylobacters. These results are discussed in relation to the phylotaxonomy of these organisms.  相似文献   
240.
为更好地弄清草鱼(Ctenopharyngodon idella)肠道纤维素降解细菌的种类,采用羧甲基纤维素(CMC)作为唯一碳源的选择性培养基,分别从草鱼肠道内容物和肠道黏膜中分离到了40株产纤维素酶细菌。16S rRNA基因序列的分析结果显示,大多数产纤维素酶细菌为气单胞菌属(Aeromonas)的种类,其次为肠杆菌属(Enterobacter)的细菌以及未经分离纯培养的细菌(Uncultured bacterium)。进一步研究细菌产纤维素酶能力发现,纤维素酶活性显著性高于其他菌株的分别是A.veronii MC2、A.veronii BC6、肠杆菌科(Enterobacteriaceae)中一种未经分离纯培养的细菌BM3(Uncultured bacterium BM3)和A.jandaei HC9。草鱼肠道中简答气单胞菌(A.jandaei)、类志贺邻单胞菌(Plesiomonas shigelloides)、阴沟肠杆菌(E.cloacae)以及产气肠杆菌(E.aerogenes)是被作为产纤维素酶细菌的首次报道。  相似文献   
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