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101.
This report concerns one case of a sphenoid sinus mucocele occurring 17 years after transsphenoidal surgery for acromegaly. In 1979, a 51-year-old man was successfully operated by the transnasal transsphenoidal approach for a growth hormone (GH) adenoma 1 cm in diameter. In 1996, the patient was hospitalized for headaches and diplopia. He presented a loss of right visual acuity with paralysis of the right oculomotor nerve. The basal GH level was normal with a satisfactory decrease after oral glucose ingestion. Pituitary sellar radiography showed a disappearance of the posterior clinoid while magnetic resonance imaging revealed the existence of a bilocular, circular, homogeneous lesion of the sphenoid sinus 3 cm in diameter with a posterior and lateral extension. The diagnosis of mucocele was confirmed by surgical treatment, allowing drainage of the mucocele through a transsphenoidal approach. The drained material was composed of sinus epithelium containing many polynuclear and resorptive cells. Postoperatively, the symptoms decreased dramatically, leading to full recovery of visual function and disappearance of the headaches. Apart from the tumor recurrence, the mucocele of the sphenoid sinus can be evoked as a possible long term complication of transsphenoidal sugery for pituitary adenoma. Received: 2 June 1998 / Accepted: 23 February 1999  相似文献   
102.
Adenohypophyses of human newborns contain characteristic psammoma bodies. Their numbers are maximal within 2 weeks of the neonatal period and diminish thereafter. They are very rare in infant pituitaries, seeming to disappear by shrinkage in that there is a significant direct correlation between their number and size. The bodies were found to contain a high concentration of endogenous peroxidase, thus suggesting that the enzyme may be responsible for their disappearance. A statistical majority of psammoma bodies were located within follicular lumens. By immunohistochemistry, the follicular epithelium surrounding psammoma bodies showed immunoreactivity for various pituitary hormones. Light microscopy demonstrated that adenohypophysial cells surrounding psammoma bodies contain randomly, scattered granules or globules exhibiting peroxidase activity. Extrusion of such granules into follicular lumens may play a role in the genesis of the concretions. The conspicuous lamellar nature of the calcified psammoma bodies suggests that waves of calcium deposition occur during their morphogenesis. Despite histologic similarities, the histochemical characteristics of this type of psammoma body differ from those in other organs as well as from the calcification encountered in prolactin (PRL)-producing pituitary adenomas.  相似文献   
103.
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   
104.
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   
105.
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   
106.
Patch-clamp recording techniques were applied to thin slices of the rat pituitary gland in order to study synaptic transmission between hypothalamic nerve terminals and neuroendocrine cells of the intermediate lobe. Inhibitory postsynaptic currents (IPSCs) could be evoked by electrical stimulation of afferent neuronal fibres in the surrounding tissue of the slice. The IPSCs could be evoked in an all-or-nothing mode depending on the stimulus intensity, suggesting that single afferent fibres were stimulated. They had a chloride-dependent reversal potential and were blocked by bicuculline (K d=0.1 M), indicating that they were mediated by -aminobutyric acid A (GABAA) receptors. In symmetrical chloride solutions the current/voltage relation of the IPSC peak amplitudes was linear. The IPSCs were characterized by a fast (1–2 ms) rise time and a biexponential decay, with time constants of 21±4 ms and 58±14 ms at a holding potential of –60 mV (n=6 cells). Both decay time constants increased with depolarization in an exponential manner. Spontaneously occurring IPSCs had a time course that was similar to that of evoked IPSCs. These miniature IPSCs, recorded in 1 M tetrodotoxin, displayed an amplitude distribution that was well fitted by single Gaussian functions, with a mean value of its maxima of 18.1±2.3 pA (n=4 cells). Amplitude histograms of evoked IPSCs were characterized by multiple peaks with a modal amplitude of about 18 pA (n=6 cells). These findings indicate the quantal nature of GABAergic synaptic transmission in this system, with a quantal conductance step of about 280 pS. Single-channel currents underlying the IPSCs were studied by bath application of GABA to outside-out patches excised from intermediate lobe cells. Such GABA-induced currents revealed two conductance levels of 14 pS and 26 pS. In conclusion, GABAergic synaptic transmission in neuroendocrine cells of the pituitary has properties that are quite similar to those observed in neurones of the central nervous system.  相似文献   
107.
目的:检测垂体腺瘤组织中垂体肿瘤转化基因(PTTG)、bFGF mRNA的表达,分析其与垂体腺瘤侵袭性的关系及临床意义。方法:应用逆转录PCR(RT—PCR)方法检测30例垂体腺瘤组织标本中PTTG、bFGF mRNA的表达,分析二者与垂体腺瘤侵袭性的关系。结果:侵袭性垂体腺瘤组的PTTG、mRNA表达、bFGF mRNA表达均较非侵袭性腺瘤组增高,其差异具有统计学意义。结论:垂体腺瘤侵袭性的发生与垂体肿瘤转化基因(PTTG)表达增高及其上调血管生成正调节因子bFGF并表达、促进血管生成有关,  相似文献   
108.
目的 探讨大垂体肿瘤立体定向放射治疗(stereotatic radiotherapy,SRT)的效果和视力保护问题。方法 11例大垂体肿瘤患者,肿瘤中位直径为4 cm,2例垂体肿瘤距视神经或视交叉的距离≥2 mm,其余患者肿瘤则紧贴视神经或视交叉。本组患者用X线分次立体定向放射治疗,每次剂量为5~7 Gy,每周2~3次,总剂量为40 Gy。做计划时使80%等剂量线避开视神经或视交叉。结果 肿瘤经分次SRT后体积明显缩小90.9%(10/11),视力有改善者占90.9%(10/11)。结论 SRT治疗大垂体肿瘤是有效的,对于肿瘤距视神经或视交叉的距离≤2 mm的垂体肿瘤,只要掌握好合适的分割剂量和次数,不会出现视力障碍。  相似文献   
109.
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   
110.
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   
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