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141.
142.
Unlike acetylcholine, caffeine was much more effective in releasing catecholamine in the absence of extracellular Ca2+ than in its presence in perfused cat adrenal glands. The intracellular Ca2+ antagonist, TMB-8 (10−4 M), inhibited reversibly the catecholamine secretion evoked by caffeine (40 mM) and that induced by acetylcholine (10−4 M) in the presence of hexamethonium (10−3 M) during perfusion with Ca2+-free Locke solution containing EGTA (10−5 M). These results support our view that muscarinic receptor activation causes catecholamine secretion by mobilizing Ca2+ from an intracellular pool just as caffeine does. 相似文献
143.
144.
Isao Nishimori Kazuichi Okazaki Yasuro Yamamoto Masanori Morita Satoru Tamura Yasutake Yamamoto 《Journal of clinical immunology》1993,13(4):265-271
The specific cellular immune response to the partially purified pancreatic antigen was studied by the peripheral blood lymphocyte proliferation assay in patients with chronic pancreatitis, Sjögren's syndrome, and primary biliary cirrhosis. A significant positive result (stimulation index >2.0) was observed in 7 of 21 patients with idiopathic chronic pancreatitis (33%;P<0.05), 6 of 7 patients with Sjögren's syndrome-associated chronic pancreatitis (86%;P<0.0005), and 6 of 11 patients with Sjögren's syndrome (55%;P<0.01), compared to normal controls whose stimulation index was 0.94±0.28 (mean ± SD;n=14; range, 0.56–1.60). On the other hand, patients with alcoholic chronic pancreatitis (17%;n=12), stone-related chronic pancreatitis (0%;n=7), primary biliary cirrhosis-associated chronic pancreatitis (33%;n=3), primary biliary cirrhosis (0%;n=4), systemic lupus erythematosus (17%;n=6), and autoimmune thyroiditis (0%;n=6) showed no significant difference from normal controls. Furthermore, in patients with idiopathic chronic pancreatitis who had positive results, a lymphocyte proliferative response to the pancreatic antigen was observed in T cells, especially in the CD4+ T cell subpopulation. These results suggest that the pancreatic antigen plays a role in the pathogenesis of a part of idiopathic chronic pancreatitis and Sjögren's syndrome in association with T cell responses and, also, suggest that autoimmunity may be a possible etiological factor in chronic pancreatitis. 相似文献
145.
Morphogenesis of nonpolypoid colorectal adenomas and early carcinomas assessed by cell proliferation and apoptosis 总被引:4,自引:0,他引:4
Nomura M Watari J Yokota K Saitoh Y Obara T Kohgo Y 《Virchows Archiv : an international journal of pathology》2000,437(1):17-24
Nonpolypoid neoplasms, as well as ordinary polypoid tumours, are occasionally found in the colorectum. To clarify whether
cell kinetic status affects the macroscopic morphology of colorectal neoplasms, we investigated proliferative indices (PI),
apoptotic indices (AI), and the expression of apoptosis-related gene products. We examined 110 colorectal neoplasms comprised
of 36 polypoid, 38 flat elevated and 36 depressed tumours. According to WHO’s criteria these tumours consisted of 61 adenomas
with low grade dysplasia (LGD), 30 adenomas with high grade dysplasia (HGD) and 19 carcinomas with submucosal invasion. Apoptotic
cells were detected by TUNEL staining. Proliferating cells and apoptosis-related gene products were assessed by immunohistochemistry
for Ki-67, p53, Bcl-2, and Bax antigens. AI were closely associated with macroscopic morphology in adenomas but not in carcinomas.
PI were relatively constant among the three macroscopic types in adenomas and carcinomas. Median AI values of polypoid, flat
elevated and depressed tumours were 1.8%, 2.1% and 4.6% for adenomas with LGD, 0.8%, 2.4% and 6.2% for adenomas with HGD and
2.9%, 4.0% and 3.6% for carcinomas, respectively. Overall PI were significantly higher in carcinomas than in adenomas with
LGD, whereas AI were not different. Although the incidence of expression was significantly higher in carcinomas for p53 and
in adenomas for Bcl-2 than the others, the expression of apoptosis-related gene products (p53, Bcl-2 and Bax) was similar
among polypoid, flat elevated and depressed tumours. Macroscopic morphology of colorectal adenomas is determined by the apoptosis
not by proliferation, and high apoptosis found in depressed adenomas implies their low net growth.
Received: 1 July 1999 / Accepted: 17 January 2000 相似文献
146.
Crawford Anderson David R. Knibbs Steven J. Abbott Carl Pedersen David Krutchkoff 《Ultrastructural pathology》1990,14(3):263-271
Previous immunocytochemical studies of pleomorphic adenomas have demonstrated consistent labeling with glial fibrillary acidic protein (GFAP). Cross-reactivity with other intermediate filaments of similar structure and chemical composition has been suggested to account for this seemingly inappropriate pattern of immunoreactivity. To investigate further this phenomenon, we examined five pleomorphic adenomas by immunoelectron microscopy. Ultrastructural features were similar to those described by other investigators, with ductal epithelium being surrounded by myoepithelial cells and modified cells becoming detached to form the isolated stellate and spindle cells of the stroma. As part of this process, many neoplastic myoepithelial cells appeared to lose their specialized ultrastructural features, assuming a rather undifferentiated appearance. Single and double immunoelectron microscopic labeling showed vimentin filaments in all these neoplastic myoepithelial cells. In contrast, GFAP filaments were identified only in the most undifferentiated cells. Such restriction of GFAP filaments to an ultrastructurally definable subset of neoplastic cells provides strong evidence against nonspecific staining due to cross-reactivity. Given the previously described coexpression of vimentin and GFAP by neoplastic cartilage, it appears likely that this immunophenotype in neoplastic myoepithelial cells reflects early chondroid differentiation. 相似文献
147.
孕期四氯二苯对二噁英处理对子鼠颌下腺表皮生长因子和表皮生长因子受体的影响 总被引:1,自引:0,他引:1
目的 研究孕期四氯二苯对二噁英(TCDD)处理对子鼠颌下腺表皮生长因子(EGF)和表皮生长因子受体(EGFR)的影响。方法 孕15d大鼠给予TCDD(5μg/kg)灌胃1次,采用免疫组织化学方法,对不同发育阶段的子鼠颌下腺进行了观察。结果 在PND32,PND49d,TCDD组颌下腺EGF和EGFR的免疫反应阳性产物比对照组丰富,有显著性差异。结论 孕期TCDD暴露促进了青春期和青春前期子鼠颌下腺EGF的生成和EGFR的表达。 相似文献
148.
目的:对耳大神经及腮腺筋膜解剖进行再认识,由此改良腮腺切除手术方法。方法:解剖成人尸体10侧,术中活体解剖20侧,对耳大神经和腮腺筋膜的解剖要素进行观察。根据观察结果进行改良腮腺切除术14例,即在腮腺筋膜表面翻瓣后,由前向后另翻腮腺筋膜瓣,切除腮腺后将筋膜瓣复位缝合,完整保留耳大神经和腮腺筋膜。结果:耳大神经在下颌角水平之上0-2cm依次分耳后、耳垂、耳前支,神经主干末段和分支起始段均分布于腮腺筋膜浅层表面,后者致密,其致密纤维包裹在神经周围。改良手术后2例(14.3%)发生轻度Frey’s综合征,无1例发生术区皮肤长期麻木、长期面瘫、涎瘘及肿瘤复发。结论:耳大神经各分支和腮腺筋膜具有不可代替的解剖生理功能,改良术式能将两者完好保留,显著降低术后并发症。 相似文献
149.
A. Hagedorn P.-G. Germann U. Junker-Walker A. Tomovic W. Seewald A. Polkinghorne A. Pospischil 《Experimental and toxicologic pathology》2005,57(2):418-159
Fms-like tyrosine kinase 1 (Flt-1) performs a subordinate effector role in mesenchymal angiogenesis and potentially serves an equally important functional role as a self-contained receptor in epithelial cells. In both endothelial cells and epithelial cells, Flt-1/vascular endothelial growth factor receptor 1 (VEGFR1) downstream signalling is involved in regulating cellular processes such as cytoskeletal changes and cellular survival protection. Cellular renewal of the gastrointestinal mucosa is based on these processes and might involve Flt-1/VEGFR1 pathway activities; the molecular mechanisms regulating these cellular dynamics remain unclear. This study was performed to investigate the presence and distribution of Flt-1/VEGFR1 in epithelial cells of the gastrointestinal tract by immunohistochemistry (IHC). Gastrointestinal tissues were taken from eight anatomical sites from mouse, rat, dog, swine and monkey. Present results revealed a cytosolic Flt-1/VEGFR1 staining pattern in mucosal epithelial cells for all investigated species. Non-epithelial structures also displayed a distinct Flt-1/VEGFR1 positivity and included vascular smooth muscle walls, enteric smooth muscle layers, the enteric nervous system and capillary endothelial cells. Diverse intensities of the Flt-1/VEGFR1 binding reaction within each species were observed in the intestinal mucosa with a strong immunoreaction in enterocytes and with a low protein expression in the ileum in most species. Crypt cells in the large intestine were mostly negative for Flt-1/VEGFR1. A peculiar and mainly intranuclear antibody binding reaction was found in Brunner's gland epithelial cells of mouse and rat whereas Brunner's glands of dog, swine and monkey remained completely negative. These results indicate a potential involvement of Flt-1/VEGFR1 in normal restitution of gastrointestinal structures in the species studied. Additionally, intranuclear Flt-1/VEGFR1 antibody binding in Brunner's glands of rodents may suggest a nuclear translocation of the transmembrane VEGFR1 which has not previously been described. 相似文献
150.