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71.
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   
72.
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   
73.
Summary In a case of congenital paramyotonia a muscle biopsy was performed and studied morphologically, histochemically and ultrastructurally. A clearcut pattern of changes has been observed with ATPase and oxidative enzymes. On electron microscopy special changes known as tubular aggregates were found. The relationship between the two findings, as well as the significance of such alterations in the range of periodic paralyses and myotonic phenomena, are discussed.
Zusammenfassung Bei einem Fall von kongenitaler Paramyotonie wurde eine Muskelbiopsie lichtmikroskopisch, histochemisch und elektronenoptisch untersucht. Typische Veränderungen ergaben sich in der ATPase-Färbung und in bezug auf oxydative Enzyme. Bei der elektronenoptischen Untersuchung wurden sogenannte tubuläre Aggregate festgestellt. Es wird die Beziehung der zwei Gruppen von Veränderungen zueinander diskutiert sowie auch die Bedeutung derselben im Rahmen der periodischen Lähmungen und der myotonen Phänomene.
  相似文献   
74.
This study investigated whether focal atrophy is a degenerative process of a whole tubule or tubular blockade as partial intratesticular degeneration. Serial section analyses of testicular tissue from 19 men with different andrologic diseases were examined. From every fifth section of any series, defined areas were viewed under a light microscope, and tubule sections were drawn. Three-dimensional reconstructions were made from these materials. Reconstructions of the seminiferous tubules showed tubular blockade as partial degeneration of the tubules. Transition from an intact portion to a blockade was accompanied by an increase in the thickness of the lamina propria. The blockade was a cell cord that contained Sertoli cells and, at most, spermatogonia, or it was a completely atrophied tubule, a so-called tubular scar. In a given tubule, defined areas of atrophy and areas of spermatogenic activity were both found. Occurrence of tubular blockade increased with age. Serial section analyses of testicular tissue showed tubular blockade as the partial degeneration of seminiferous tubules. In focal atrophy, a given tubule can have defined areas of atrophy and areas of spermatogenic activity. Received: 25 August 1999 / Accepted: 21 April 2000  相似文献   
75.
The outcome of patients with acute renal failure (ARF)due to acute tubular necrosis (ATN) was evaluated inthis study. Two hundred and twenty-two patients witha mean age of 55.l ± 17.7 years (range 19–97years; male 153, female 69) who developed ATN in theperiod from July 1991 through January 1997 werestudied. Patients were divided into four groupsaccording to their APACHE II scores at the time of thediagnosis of ATN. Group I included patients with anAPACHE II score of 14 or less (n = 70), Group II with ascore of 15–18 (n = 52), Group III with a score of 19–23(n = 58), and group IV with a score of 24 or above(n = 42). The mean APACHE II score for each of the fourstudy groups was 11 ± 0.4, 16 ± 0.2, 20 ±0.2, and 29 ± 0.7, respectively. Patient survivalwas evaluated by the Kaplan-Meier analysis withcensorship at 12 months. Survival rates at 180 dayswere 67%, 47%, 39%, and zero%, for group I through IV respectively, χ2 = 27.99, p < 0.0001,with a median survival of >365, 120, 31, and 11days, for groups I through IV, respectively. For patients with oliguria (n = 88) survival at 180days was 23% vs. 58% for patients without oliguria(n = 134), p < 0.0001, median survival 13 vs. 364 d.Six months survival of those who required dialysis(n = 79) was 25% vs. 58% for those whom dialysis wasnot needed (n = 143), p = 0.001, median survival 15 vs.364 d, respectively. In patients with sepsis (n = 58),6 months survival was 35% vs. 50% for those withoutsepsis (n = 164), p = 0.013, median survival 14 vs. 169 d. In patients who required mechanical ventilation(n = 72), 6 months survival was 17% vs. 62% for those whodid not need respiratory support (n = 150), p = 0.0001,median survival 13 vs. > 365 d, respectively. Finally, 6 months survival in patients with one(kidney only), two, three, and four organ failure was76, 30, 11, and zero percent, respectively, p = 0.0001,median survival > 365, 16, 11, and 12 days,respectively. We conclude that the use of the APACHE II score forthe stratification of the severity of illness could beof clinical utility in predicting mortality inpatients with ATN. Other predictors of poor prognosisinclude the need for dialysis, the presence ofoliguria, the need for mechanical ventilation, thepresence of sepsis, and the number of failed organs. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
76.
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   
77.
Abstract A male infant with bilateral small kidneys associated with both proximal and distal tubular dysfunction, who showed chronic renal failure soon after birth, is reported. He was also noted to have both proximal and distal type of renal tubular acidosis. The small kidneys were thought to be due to renal hypodysplasia associated with bilateral severe vesicoureteral reflux, by radiological findings. An alkalization therapy with chemo-prophylaxis seemed to be of benefit in slowing the progression of renal failure in this case.  相似文献   
78.
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   
79.
We report a neonate with neonatal hemochromatosis (NH), renal tubular dysgenesis (RTD), and hypocalvaria. NH is a fatal condition of the newborn, characterized by severe idiopathic liver failure of intrauterine onset and siderosis, intra- and extrahepatic, with sparing of the reticuloendothelial system. RTD is characterized by short, abnormally developed cortical tubules that lack proximal tubule differentiation. Although both NH and RTD have been reported as entities with a genetic component, similar findings can be secondary to in utero insults. Hypocalvaria has been reported in association with fetal hypoxia including that secondary to angiotensin converting enzyme inhibitors. This 38-week-old infant died at 8.5 h. The small nodular liver weighed 44 g. Grossly, the kidneys were normal. Hypocalvaria was present. Microscopically, the hepatic parenchyma was distorted by fibrous tracts, proliferation of bile ducts, and abundant iron deposition in hepatocytes. Extrahepatic siderosis in the pancreas, myocardium, and other organs was consistent with NH. Proximal convoluted tubules were not seen on routine stains and markers for proximal tubules were negative. Previous reports have linked NH with RTD and RTD with hypocalvaria. This infant had all three of these rare conditions, which have been hypothesized or shown to be due to genetic factors, hypoxia, or drugs. The etiology in this case is unknown. Received May 20, 1997; accepted August 15, 1997.  相似文献   
80.
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   
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