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61.
Shigeru Furuhata Toru Kameya Shigco Toya Anthony Frankfurter 《Acta neuropathologica》1993,86(5):518-520
Pituitary adenomas surgically resected from 61 consecutive patients and 9 normal pituitary glands were studied by immunohistochemistry to determine the localization of the class III-tubulin isotype (neuron-specific) which is recognized by the monoclonal antibody TUJ1. In normal pituitary glands only a few cells were weakly immunopositive for TUJ1, whereas, in 43(73%) of 61 adenomas, more than 5% of tumor cells were immunopositive. The result may indicate that this neuron-specific -tubulin isotype may be either expressed de novo or enhanced under the transformation of pituitary acinar cells to tumors.Research fellow of the Department of Pathology, Kitasato University School of Medicine where the work was conducted 相似文献
62.
W. Bonicki A. Kasperlik-Załuska W. Koszewski W. Zgliczyński J. Wisławski 《Acta neurochirurgica》1993,120(3-4):118-122
Summary Authors analised retrospectively the incidence of pituitary apoplexy in a series of 799 pituitary adenomas with respect to the long term follow-up of the patients.Focal vascular abnormalities in histological specimens of tumours, regarded as morphological suggestion of past apoplexy (heamorrhage, ischaemic infarction or necrosis), were established in 113 out of 783 surgical cases (14.4%).Acute clinical onset, justifying the clinical diagnosis of pituitary apoplexy, occurred in 39 patients only (5% of the whole series), 19 of them were subjected to urgent surgical decompression due to severe neurological deficit. The haemorrhagic character of apoplexy was established in most cases requiring immediate surgery.The detailed clinical picture of this condition and its management are discussed with respect to the long term prognosis.On this basis the authors suggest the necessity of surgical treatment in every case of pituitary apoplexy, taking into account not only neurological recovery, but also endocrine and oncological aspects of the disease. The observation that pituitary apoplexy may be a marker of tumour invasiveness (even in small, enclosed adenomas) is highlighted. 相似文献
63.
Unusual lung tumors are not simply pathological curiosities. They demonstrate features of major significance in diagnosis, treatment, and prognosis. Six of these tumours are discussed: (1) Carcinosarcoma is rarely found in the lung. The histogenis of the lesion is unclear and the prognosis is poor. (2) Only three cases of pleomorphic adenoma have previously been described. Differentiation from other "mixed tumours" of the lung is essential. (3) A rare case of bronchial adenoma producing ectopic ACTH is described. Early recognition of these polypeptide hormone-secreting tumours is stressed. (4) Oat cell carcinoma with the myasthenic (Eaton-Lambert) syndrome shows the clinical features which should permit early tumour diagnosis. The hazards of muscle relaxants must be recognized. (5) Prostatic carcinoma with endobronchial metastases is is discussed. The importance of localization of the primary tumour is emphasized. (6) An example of double primary carcinoma is presented. The rarity of this finding may be related to the poor prognosis of patients with bronchogenesis carcinoma. 相似文献
64.
Hirohito Yano Takashi Funakoshi Jun Shinoda Noboru Sakai George Kokuzawa Kuniyasu Shimokawa 《Brain tumor pathology》1997,14(1):75-78
A 35-year-old woman had an intradural tumor in the posterior fossa adjacent to the posterior wall of the left pyramidal bone,
which was totally removed and histologically diagnosed as a pleomorphic adenoma. Follow-up examination for 2 years showed
no recurrence of the tumor. There was no primary lesion in any other gland of the body, and therefore there is no alternative
but to conclude a “migration” of some gland cells. The pathogenesis of this tumor remains unclassified. 相似文献
65.
P de Lonlay-Debeney JC Fournet D Martin F Poggi C Dionisi Vicci M Spada G Touati J Rahier F Brunelle C Junien JJ Robert C Nihoul-Fékété JM Saudubray 《Archives de pédiatrie》1998,5(12):1347-1352
Persistent hyperinsulinemic hypoglycaemia of infancy (PHHI) is the most frequent cause of hypoglycaemia in infancy. Clinical presentation is heterogeneous, with variable onset of hypoglycaemia and response to diazoxide, and presence of sporadic or familial forms. Underlying histopathological lesions can be focal or diffuse. Focal lesions are characterised by focal hyperplasia of pancreatic islet-like cells, whereas diffuse lesions implicate the whole pancreas. The distinction between the two forms is important because surgical treatment and genetic counselling are radically different. Focal lesions correspond to somatic defects which are totally cured by limited pancreatic resection, whereas diffuse lesions require a subtotal pancreatectomy exposing to high risk of diabetes mellitus. Diffuse lesions are due to functional abnormalities involving several genes and different transmission forms. Recessively inherited PHHI have been attributed to homozygote mutations for the beta-cell sulfonylurea receptor (SUR1) or the inward-rectifying potassium-channel (Kir6.2) genes. Dominantly inherited PHHI can implicate the glucokinase gene, particularly when PHHI is associated with diabetes, the glutamate dehydrogenase gene when hyperammonaemia is associated, or another locus. 相似文献
66.
Genetic Alterations of Mixed Hyperplastic Adenomatous Polyps in the Colon and Rectum 总被引:1,自引:2,他引:1
Hiroyuki Uchida Hiroshi Ando Keiji Maruyama Hiroshi Kobayashi Hiroshi Toda Hiroshi Ogawa Takachika Ozawa Yasuhide Matsuda Haruhiko Sugimura Takashi Kanno Shozo Baba 《Cancer science》1998,89(3):299-306
Some mixed hyperplastic adenomatous polyps (MHAPs) contain dysplastic lesions or even carcinomas. These polyps are considered to be different from ordinary hyperplastic polyps and may have a preneoplastic potential. We investigated APC and K- ras mutations in MHAPs of the colon and rectum, and also in colorectal adenomas and hyperplastic polyps to identify molecular differences between MHAPs, adenomas and hyperplastic polyps, using direct sequencing of mutation cluster regions (MCR) in APC and K- ras . No APC mutations were identified in 12 MHAPs and 8 hyperplastic polyps, whereas 10 of 27 (37.0%) adenomas showed somatic mutations. K- ras mutations were identified in one of 12 (8.3%) MHAPs, one of 8 (12.5%) hyperplastic polyps, and 10 of 27 (37.0%) adenomas. p53 mutation was found in a carcinoma arising in an MHAP. Mutations other than APC mutations may play a role in the development of MHAPs. 相似文献
67.
目的研究垂体腺瘤(pituitary adenoma)中细胞粘附分子(CD44)的表达,探讨CD44蛋白在垂体腺瘤侵袭性生长中的意义.方法用免疫组化(SP)的方法检测38例垂体腺瘤中CD44s、CD44v5蛋白的表达.结果20例侵袭性垂体腺瘤中CD44s、CD44v5阳性率分别为75%、35%.18例非侵袭性垂体腺瘤中CD44s、CD44v5阳性率分别为27.8%、22.2%.CD44s在侵袭性垂体腺瘤中表达的阳性率明显高于非侵袭性垂体腺瘤,其差异具有显著性(P<0.01),CD44v5在侵袭性垂体腺瘤中和非侵袭性垂体腺瘤中的表达率均较低,无显著性差异(P>0.05).结论CD44s在侵袭性垂体腺瘤中呈高表达,与垂体腺瘤的侵袭性生长有关,在垂体腺瘤的侵袭性生长过程中起重要作用.CD44v5在垂体腺瘤中的表达较低,与垂体腺瘤生长方式无关. 相似文献
68.
HSV-tK与IL-2基因对涎腺多形性腺瘤细胞的杀伤作用 总被引:1,自引:0,他引:1
目的:观察腺病毒介导的单纯疱疹病毒胸苷激酶基因(HSV-tK)和白细胞介素-2基因(IL-2)联合杀伤人涎腺多形性腺瘤细胞的效果.方法:采用腺病毒介导的HSV-tK基因和IL-2基因联合转染人涎腺多形性腺瘤细胞;采用逆转录聚合酶链式反应(RT-PCR)检测转染后细胞的基因表达;采用四唑盐比色(MTT))法测定tK与IL-2基因对肿瘤细胞的杀伤作用及旁观者效应:采用光镜观察基因治疗后肿瘤细胞的形态学变化.结果:单独转染HSV-tK/GCV及IL-2基因5天后,涎腺多形性腺瘤细胞的存活率分别为37.7%和66.0%:联合转染5天后,细胞的存活率降至21.5%,与前二者相比差异有显著性(P<0.05).结论:HSV-tK和IL-2基因联合使用对涎腺多形性腺瘤的杀伤作用高于上述基因单独使用的杀伤作用. 相似文献
69.
Proliferation, Vascular Endothelial Growth Factor Expression and Cavernous Sinus Invasion in Growth Hormone Secreting Pituitary Adenomas 总被引:4,自引:0,他引:4
Summary Surgical cure of growth hormone producing pituitary adenomas (GHomas) becomes difficult when they invade the cavernous sinus
(CS). Tumour proliferative activity and angiogenesis are thought to be required for tumour growth and invasion, and vascular
endothelial growth factor (VEGF) activates neovascularization around tumours. In this study, the mechanism and clinical significance
of CS invasion is analysed. In 25 surgically treated GHomas, the extent of CS invasion was classified as high (Knosp's grade
3 and 4), and low (grade 0, 1 and 2) MR grades, and the MR grades were compared with tumour proliferative potential (Ki-67
expression), angiogenetic demand (VEGF expression), volume of adenomas and serum hormone levels.
The Ki-67 index of high MR grade adenomas (1.17±0.62%) was significantly higher than that of low MR grade adenomas (0.55±0.42%,
p=0.027), whereas VEGF expression showed no significant correlation with MR grades (p>0.999). Tumour volume also showed a
significant correlation with MR grade (p=0.002). VEGF expression was not correlated with serum hormone level and volume, but
was correlated with tumour proliferative potential. Proliferative potential and tumour volume were two independent factors
related to CS invasion. Although VEGF expression was not a direct factor related to CS invasion, it may indirectly play a
role in activation of tumour aggressiveness, which is required in CS invasion.
Our results show that high MR grade adenomas have higher proliferative ability. In order to improve the surgical outcome,
pre-operative medical debulking is indicated, particularly, in such adenomas. 相似文献
70.
Summary Background. Microsurgical selective adenomectomy is the best established method available for the treatment of Cushing's disease. However,
this surgical method warrants still more efforts to improve the results in minute microadenomas. In this paper the authors
evaluate a method of intraoperative cytological investigations during transsphenoidal surgery.
Method. Between January 1997 and September 1999, transsphenoidal surgery was performed in 75 patients with the diagnosis of Cushing's
disease. Fifty-one cases of proven microadenomas were reviewed.
Findings. Of 51 cases, 33 tumors were 3 mm or less in diameter, here after called minute adenomas. In 49 of 51 (96.1%) microadenomas,
adenoma tissue was identified by intraoperative cytological techniques. Postoperatively, only 35 of 51 ACTH-secreting microadenomas
(68.6%) were confirmed by immunostaining methods. This lower percentage was most probably due to the small amount of tissue
obtained. Therefore, in 14 cases (including 12 minute adenomas) the presence of the adenoma was only proven by cytological
preparation and clinical outcome. The sensitivity of cytological preparations in cases of confirmed Cushing's disease was
100%.
Interpretation. The method described here was particularly well suited for the intraoperative discrimination and documentation of minute
adenomas. Cytological preparation appears to be effective in improving the adenoma finding rate and the surgical outcome in
cases of Cushing's disease. 相似文献