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51.
Lucini C Maruccio L Tafuri S Bevaqua M Staiano N Castaldo L 《Anatomy and embryology》2005,210(4):265-274
Glial-derived neurotrophic factor (GDNF), neurturin (NRTN), persephin (PSPN), and artemin (ARTN) are a group of proteins belonging
to the GDNF family ligands (GFLs). GDNF, NRTN, and ARTN support the survival of central, peripheral, and autonomic neuron
populations, while PSPN supports the survival of only several central neuron populations. A common receptor, RET, modulates
the action of this family and a co-receptor, GFRα, determines RET ligand specificity. GDNF and NRTN appear to be essential
for enteric nervous system (ENS) development in mammals, zebrafish, and other teleostean species. GFLs are also essential
for the maintenance and plasticity of adult mammalian ENS. In this study, the distribution pattern of GFLs in the intestine
of five adult fish (bass, gilt-head, scorpionfish, trout, and zebrafish) was evaluated by immunochemical and immunocytochemical
analysis. The results demonstrated the presence of GDNF, NRTN, and ARTN in the gut of all species studied. They appeared to
be spread in the ENS and/or endocrine cells of the intestine. These findings suggest that the presence of GFLs in fish gut
is not only limited to developmental period, but could be also involved in the enteric physiology of adult species. 相似文献
52.
53.
Expression of oncogene products, anti-oncogene products and oncofetal antigens in intraductal papillary-mucinous neoplasm of the pancreas 总被引:1,自引:0,他引:1
A few previous studies have demonstrated the expression or mutations of oncogenes and anti-oncogenes as well as that of oncofetal antigens in intraductal papillary-mucinous neoplasm of the pancreas. In this study, we have investigated the immunohistochemical expression of oncogene (ras and c-erbB-2) and anti-oncogene (p53 and retinoblastoma [Rb]) products and oncofetal antigens (CEA, CA19-9 and DUPAN-2) in nine such tumours of the pancreas. In normal pancreas (5 cases), the Rb gene product and CA19-9 were expressed in all cases, while ras and c-erbB-2 gene products, p53 protein, CEA and DUPAN-2 were not expressed. In intraductal papillary-mucinous tumours (n = 9), ras, c-erbB-2, p53 and Rb gene products were present in 4/9 (44%), 7/9 (78%), 0.9 (0%) and 6/9 (67%) cases, respectively. CEA, CA19-9 and DUPAN-2 were expressed in 8/9 (89%), 9/9 (100%) and 2/9 (22%) cases respectively. In invasive ductal adenocarcinoma of the pancrease (7 cases), ras, c-erbB-2, p53 and Rb gene products were expressed in 3/7 (43%), 6/7 (86%), 2/7 (29%) and 3/ & (43%) cases respectively. CEA, CA19-9 and DUPAN-2 were expressed in 7/7 (100%), 7/7 (100%) and 6/7 (86%) cases, respectively. The extent and intensity of the expression of these antigens was greater in invasive ductal adenocarcinomas. These data suggest that activation of ras and c-erbB-2 oncogenes and inactivation of Rb anti-oncogene may contribute to the development and progression of intraductal papillary-mucinous tumours of the pancreas and that there is neo-expression of CEA and DUPAN-2 during the development and progression of these tumours. 相似文献
54.
Anne Mellon Mogensen Esther Hage Steffen Bülow 《Virchows Archiv : an international journal of pathology》1989,414(4):321-324
Summary Electron microscopical studies on endocrine cell hyperplasia of duodenal adenomas from five patients with familial adenomatous polyposis were performed. All the endocrine cell types normally found in the duodenal mucosa were identified. A constant feature was proliferation of duodenal-enterochromaffin cells but an increase in the number of all other endocrine cell types apart from pyloricgastrin cells and somatostatin cells, was also observed. Certain types of intestinal endocrine cells (the intestinal enterochromaffin cell and the glicentin cell) are rare cells in the normal duodenal mucosa. The finding of these cells may indicate increased biological aggressivity. 相似文献
55.
G. Paraskevas B. Papaziogas C. Lazaridis P. Gigis T. Papaziogas 《Surgical and radiologic anatomy : SRA》2002,23(6):437-442
Abstract: Three cases (two male, one female) of annular pancreas are presented, which were found and operated on within the last three decades. Diagnosis was made using imaging techniques, especially ultrasonography and computed tomography. In two cases there was incomplete obstruction, while in the other obstruction was complete. It is characteristic that in the case of complete obstruction the annular portion of the pancreas attached to a circular band of connective tissue, while in the two cases of incomplete obstruction there was a complete ring of pancreatic tissue. In all cases surgical intervention was needed in order to create a bypass. In the first case gastroenterostomy and truncal vagotomy was performed, in the second latero-lateral duodeno-jejunostomy and in the third latero-lateral antropyloroduodeno-jejunostomy. The embryology and morphology of the annular pancreas, the morphology of its duct system, diagnosis, differential diagnosis and the surgical treatment of this rare condition are reviewed. 相似文献
56.
57.
胆总管的矢状断层解剖研究 总被引:1,自引:0,他引:1
在30套成人腹部连续矢状断层标本上,胆总管与下腔静脉主要出现于R2-R3断层;胆总管胰腺段与胰头的关系有部分包埋,完全包埋及胰腺后型;十二指肠大乳头集中出现于R3断层;胆总管的行程有4种形式。文内还探讨了矢状断层里胆总管各段的毗邻及识别标志。 相似文献
58.
Branches of the splenic artery and splenic arterial segments 总被引:2,自引:0,他引:2
Daisy Sahni A Indar Jit B Gupta CN Gupta DM Harjeet E 《Clinical anatomy (New York, N.Y.)》2003,16(5):371-377
In 200 adult autopsy specimens, the arterial supply to the pancreas and spleen was studied radiologically and by manual dissection. The splenic artery divided into two or three lobar arteries, which supplied its corresponding lobe; each lobar artery subsequently divided into two to four lobular branches. Six to twelve lobular branches were observed entering the splenic substance at the hilum. Lobar arteries did not anastomose with each other, hence, the lobes of the spleen are also termed segments. The lobules, however, were not found to be independent segments and the arteries of one lobule anastomosed with those of other lobules. The branching pattern of the splenic artery varied from one specimen to another, so much so that a prevailing pattern could not be identified. Polar arteries, particularly to the superior pole, arose quite proximal to the hilum in 51% of cases and were occasionally missed. In 45% of males and 40% of females, the posterior gastric artery arose from about the middle of the splenic artery. The splenic artery was not found to be tortuous in fetuses, newborns, and young children. Tortuosity was seen in only 10% of adults; thus, the characteristic tortuosity of the splenic artery appears to develop with age. 相似文献
59.
Masafumi Hara Yutaka Tsutsumi 《Virchows Archiv : an international journal of pathology》1986,408(4):385-394
Summary Twenty-one specimens of heterotopic pancreas were investigated using the indirect immunoperoxidase method for insulin, somatostatin, glucagon, pancreatic polypeptide (PP) and gastrin. Ten specimens showed ducts, acini and islets, seven showed ducts and acini, and four showed a ductal component alone. Pyloric gland-like mucous glands were occasionally identified in association with the ductal component. In eight of ten lesions containing islets, the islets were round and had a clearly defined outline with many glucagon cells and either none or a modest number of PP cells (dorsal type). In the remaining two lesions, the islets showed varying sizes and irregular outline with many PP cells and a few or no glucagon cells (ventral type). In either type of islets, insulin and somatostatin were detected, but gastrin cells were absent. Some isolated endocrine cells were also present among the acinar and ductal components. Their occurrence in ducts was more frequent in lesions or areas mainly composed of the ductal compoment than in those with less prominent ductal tissue. In eight lesions a few gastrin cells were found in the ductal component which showed goblet cell metaplasia and pyloric gland metaplasia. An intimate relationship between goblet cell metaplasia and appearance of G cells is noteworthy. 相似文献
60.
肝肾胰器官簇移植临床解剖学研究 总被引:1,自引:3,他引:1
目的:为了开展肝肾胰器官簇移植提供应用解剖学资料和术式设计方案。方法:对24具成人尸体进行解剖观察,了解其主要血管分布,胆管、输尿管、胰管的位置以及腹腔内空腔脏器的相互关系。结果:测得主要血管腹主动脉平均长度19.20cm,上端外径2.21cm;下腔静脉平均长度19.42cm,上端外径2.60cm;门静脉长5.59cm,宽度1.49cm;肝固有动脉长3.85cm,宽0.64cm;胆总管长4.19cm,宽度0.78cm;在输尿管平均长度为27.11cm,右输尿管平均长度为25.93cm。对器管簇移植的整体切取、修整、安放和吻合提供多种方案。结论:肝肾胰器官簇移植手术有应用解剖学依据的可行性,按形态学规律有多种合理的术式设计方案 相似文献