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81.
A 51-year-old woman underwent orthotopic liver transplantation because of a small-duct primary sclerosing cholangitis associated with chronic ulcerative colitis and a hepatoportal arteriovenous fistula. Arteriograms before liver transplantation and specimen arteriograms revealed a convolution of arteries in the right hepatic lobe which communicated with a massively dilated and partly thrombosed portal vein branch. The lesion was probably the result of a previous liver biopsy. Microscopic examination of the fistula and of specimens taken at a distance from the fistula showed prominent intimal fibroplasia of portal vein branches. The vascular changes were so severe that hepatic artery and portal vein branches closely resembled each other on routine sections. We are unaware of such a finding in other conditions and therefore believe that recognition of the described vascular abnormalities in liver biopsy specimens should lead pathologists to comment that an arterioportal fistula might be present.  相似文献   
82.
We often see perilobular necrosis of the pancreas in patients with liver disease at autopsy. This study was undertaken to determine the frequency and the mechanism of development of pancreatic perilobular necrosis in patients with liver disease. Pancreatic perilobular necrosis was seen in 21 per cent of 261 autopsied patients: in 41 per cent of 73 autopsied patients with liver disease and in 13 per cent of 188 autopsied patients without liver disease. Moreover, splanchnic congestion was present in 90 per cent of 30 pancreatic perilobular necrosis patients with liver disease. These data indicate that patients with liver disease develop perilobular necrosis of the pancreas more often than patients without liver disease, and that the high frequency may be a sequela of splanchnic congestion; that is, congestion of the pancreas and endotoxaemia due to congestion of the gut.  相似文献   
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85.
Formalin-fixed paraffin-embedded hippocampal sections of brains with early-onset and late-onset Alzheimer's disease were studied immunohistochemically with antisera against cathepsin D and cathepsin B. In addition to the staining of neuronal perikarya, some of the senile plaques visualized by Bielshowsky silver staining and some of reactive astrocytes were positively stained with the antisera against cathepsin D and cathepsin B in brains with Alzheimer's disease. Abnormal localization of cathepsin D and cathepsin B immunoreactivity in neuronal perikarya was observed in brains with early-onset Alzheimer's disease. These findings demonstrate that the distribution of lysosomal proteases was altered in brains with Alzheimer's disease, suggesting the primary and/or secondary involvement of the lysosomal proteases in the pathological process of Alzheimer's disease.  相似文献   
86.
Summary Activities of glycolytic enzymes in the aorta were investigated in female Wistar rats. There were two groups of rats; one served as the control (sedentary rats), while the other group was forced to run on a treadmill for 10 weeks. In the control animals, the activities of hexokinase, phosphofructokinase and aldolase were relatively lower than those of the other glycolytic enzymes (phosphoglucose isomerase, lactate dehydrogenase and pyruvate kinase). After exercise, the activity of phosphofructokinase increased by 15%, whereas the other enzymatic activities were much the same as in the controls. Within the limits of the experiments, the increased percentage of phosphofructokinase was statistically significant (p<0.05). Since phosphofructokinase is a putative rate limiting enzyme, this enzymatic activation may indicate that glycolytic activity in the rat aorta is enhanced during and after running exercise.  相似文献   
87.
Athymic BALB/c-nu/nu (nu/nu) mice were inoculated i.p. with Coxsackie virus B3. The infected nu/nu mice were studied histopathologically, virologically and serologically in comparison with BALB/c-nu/+ (nu/+), BALB/c-+/+(+/+) and conventional ddY/S mice inoculated with the same virus. The virus titre in the hearts of nu/nu mice was roughly similar to that of nu/+ or +/+ and was higher than that of ddY/S. The neutralizing antibody titre in nu/nu mice was slightly lower than that of nu/+ or +/+ mice and somewhat lower than that of ddY/S mice. Histopathologically, there was a lack of mononuclear cells in myocarditis produced by Coxsackie virus B3 in athymic nu/nu mice. In contrast, myocarditis with mononuclear cell infiltrations were found in nu/+, +/+ and ddY/S mice. The lack of mononuclear cell reaction was a distinguishing difference in the myocardial changes of athymic nu/nu mice from those in nu/+, +/+ and ddY/S mice. The incidence in the myocardial lesions of nu/nu mice was about the same as those in nu/+, +/+ and ddY/S mice. However, the intensity of the myocardial changes of nu/nu mice was significantly less than that of other three groups. From the histopathological viewpoint, it is suggested that inflammatory response in the myocardium of mice infected with Coxsackie virus B3 is thymus-dependent.  相似文献   
88.
We studied a sensitivity of HPV DNA detection by in situ hybridization method using 3H labeled HPV DNA. The materials were CaSki cells and SiHa cells which were derived from as a negative control. The total cellular DNAs extracted from these cell lines were estimated copy numbers of HPV 16 DNA using Southern blot hybridization. In our result, CaSki cell has 400 copies/cell, SiHa cell were appeared to have 1-5 copies/cell. Simultaneously these cells were fixed by periodate-buffered lysine-paraformaldehyde-glutaraldehyde (PLPG) and were detected HPV 16 DNA using in situ hybridization. We detected HPV 16 DNA in CaSki cells and SiHa cells by in situ hybridization also. We concluded that the sensitivity of our in situ hybridization technique is 1-5 copies/cell.  相似文献   
89.
Solitary fibrous tumor (SFT) occurring at various extrapleural sites is sometimes difficult to diagnose because of its histologic variability. Although a solitary fibrous tumor is usually a slow-growing tumor with favorable prognosis, a small number of malignant cases have been reported. In the present study, we examined the clinical behavior, histologic, immunohistochemical and molecular features of 17 cases of extrapleural SFT. Four tumors were located in the pelvic cavity, two in the nasal cavity, two were confined to the pulmonary parenchyma, and there was one each in the meninges, kidney, mediastinum, retroperitoneum, temporal region, neck, groin, buttock and thigh. Histologically, all the tumors were characterized by the presence of areas consisting of a proliferation of bland spindle cells with variable amounts of thick, often hyalinized or keloid-like intercellular collagen bundles. Highly cellular areas were observed in three tumors, frequent mitoses in two, and cellular pleomorphism and tumor necrosis in one each. All 17 tumors showed immunoreactivity to CD34 and 15 (88%) to bcl-2 protein. The labeling indices of p53, mdm2 protein and Ki-67 were generally low. PCR-SSCP and a subsequent sequence analysis of the p53 gene disclosed point mutation at codon 161 in exon 5 in one of the 13 cases analyzed. According to follow-up information, none of the patients had developed local recurrence or distant metastasis. Our results suggest that most extrapleural SFTs behave in a benign fashion even in a higher histologic grade group, and it is difficult to predict their clinical outcome. Complete surgical excision in order to obtain clear margins and long-term follow-up is advisable for patients with an extrapleural SFT.  相似文献   
90.
We evaluated a novel method of computed tomography (CT) analysis using formalin-fixed lungs of autopsy cases with mild emphysema. Eight formalin-inflated lungs (FILs) obtained at autopsy were examined using CT after draining off the formalin and air inflation with an air pump, and subjected to pathological study including pathological scoring of emphysema and microscopic image analysis (MIA). Satisfactory CT examination was carried out within 5 h of lung fixation. The mean alveolar area determined by MIA correlated highly with the lung volume (r=0.845) and CT score (r=0.722). This method is simple compared with conventional polyethylene glycol fixation for CT and enables CT examination of resected lungs without anxiety about biohazards. Mild emphysema can be detected by MIA.  相似文献   
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