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101.
Intrahepatic biliary tree with either florid duct lesions or a moderate to severe degree of the duct loss in four livers with chronic hepatic diseases other than primary biliary cirrhosis were studied with histometric and serial section observations. Florid duct lesions, distributed segmentally in the liver, were found in one case with incomplete septal cirrhosis and one case with idiopathic portal hypertension. The florid duct lesions including marked plasma cell infiltration and occasional periductal granulomas, were not associated with any bile duct loss in the two cases. The duct lesions were reversible in one case during a long clinical course. On the other hand, a moderate to severe bile duct loss with biliary epithelial degeneration and necrosis was associated with no or little periductal inflammatory cell infiltration in one other case with chronic intrahepatic cholestasis, probably drug-induced, and in one case with idiopathic portal hypertension. Although florid duct lesions and bile duct loss were important diagnostic features of primary biliary cirrhosis, one of them was observed to develop independently in severely diseased livers, not consistent with a diagnosis of primary biliary cirrhosis, sclerosing cholangitis or intrahepatic bile duct paucity syndrome.  相似文献   
102.
A patient who had disseminated vascular tumors involving the bilateral ovaries, bilateral lungs and pleura, pericardium, and mediastinum is reported. The tumors were histologically of the capillary, and partly the cavernous, type of hemangioma. However, endothelial cell growth was prominent in some areas, especially in the lung, and the histology of the lung tumor resembled epithelioid hemangioendothelioma or intravascular bronchiolo-alveolar tumor (IVBAT). In the endocardium of the right atrium, an endothelial tumorous projection was observed, and there were tiny foci of tumor cell nests in the abdominal venous wall. Small lymphangiomas were also found in the subcapsular region of the spleen. These findings suggest that there had been an abnormal proliferation of systemic endothelial cells and that tumors of endothelial cell origin with diverse histological patterns developed with this condition as a background. The autopsy finding of fibrin thrombi in multiple organs as well as laboratory data including thrombocytopenia suggest that this case belongs to the "Kasabach-Merritt syndrome."  相似文献   
103.
Step-sections of 96 whole kidneys from 50 chronic hemodialysis patients were subjected to a histopathological and quantitative investigation with regard to the development of renal neoplastic lesions. The range of hemodialysis duration was from 1 to 222 months. A total of 349 renal cell adenomas were found in 41 cases (82%). They were commonly multiple and present bilaterally. Renal cell carcinomas were evident in four cases (8%), with hemodialysis durations of 54, 57, 112 and 222 months. The incidence of adenomas increased in a hemodialysis duration-dependent manner, indicating a high risk of renal cell tumor development in chronic hemodialysis patients. Furthermore, acquired cystic disease of the kidney (ACDK) was also observed in 12 cases (24.0%), where the mean hemodialysis period was 143.4 ± 48.0 months. This value was significantly longer than that of non-ACDK cases (P < 0.001). There was, however, no clear relationship between the appearance of ACDK and renal cell tumors. The present results underline the necessity for attention to possible neoplasia of the kidney in patients on long-term hemodialysis.  相似文献   
104.
A 73-year-old Japanese man with a history of partial gastrectomy due to gastric cancer 4 years previously was admitted because of intermittent fever. The patient developed abdominal pain, erythema, and myalgia in addition to the fever during the final clinical course, and died of acute heart failure. Autopsy disclosed atrophy of the left lobe of the liver and acute myocardial infarction. Neither metastasis nor recurrence of the cancer was observed. Small and medium-sized arteries of the visceral organs showed various stages of necrotizing vasculitis with narrowing of the lumina. The vasculitis was most prominent in the left lobe of the liver and in the heart. Narrowing of the portal vein due to portal tract inflammation in addition to vasculitis of the hepatic arteries may have induced ischemia and infarction, which had resulted in atrophy of the left hepatic lobe. Acta Pathol Jpn 42: 662–666, 1992.  相似文献   
105.
A clone of NIH3T3 transformant (H3) can yield subcutaneous tumors and experimental pulmonary metastasis in nude mice. Compared to H3 in culture, the cells after in vivo tumor growth (H3-N) acquired enhanced tumorigenicity and metastatic ability. Also, indirect immunofluorescence revealed that cellular fibronectin (c-FN) of H3-N was decreased remarkably. We have studied the interactions between H3 and extracellular matrices to elucidate these phenomena. In the present study, we observed the effect of NIH3T3, H3, and H3-N cultured in type I collagen gel. Morphologically in the collagen gel, NIH3T3 assumed an extensive elongated fiber-like shape, H3 assumed a moderately elongated shape, and H3-N assumed a round or spindle shape with short pseudopodia. Compared to conventional cultures on dishes, cell proliferation of all three types was suppressed in collagen gel, but the degree of the suppression was least in H3-N. As a result, H3-N grew fastest in collagen gel. The variants which acquired growth advantage in the subcutaneum of mice also kept it in collagen gel. H3 cells were cultured in type I collagen gel for 4 weeks, a period comparable to that of tumor formation in nude mice. The cells after this long-term culture (H3-C) acquired enhanced tumorigenicity and metastatic ability nearly equal to that of H3-N. FACS analysis revealed that the c-FN of H3-C had decreased to a value comparable to that of H3-N. This means that type I collagen gel as well as subcutaneous tissues could select variants of H3 with less c-FN through proliferation. Moreover, it is suspected that lattices of type I collagen regulate cell proliferation of fibroblast via c-FN. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
106.
The 6-amino-6-deoxy-N-acetylmuramyldipeptides and their 6-acylamino derivatives were shown to be active as adjuvants on the induction of delayed-type hypersensitivity to azobenzenearsonate-N-acetyl-l-tyrosine in guinea pigs. However, 6-acylamino-6-deoxy-N-(acyl)muramyldipeptides were inactive as adjuvants.  相似文献   
107.
A bacterial lectinlike substance, which is considered to participate in the adherence of Eikenella corrodens to various host cells, was purified from E. corrodens cells. The substance was extracted in 1% Triton X-100 with sonication from the cell envelope of E. corrodens 1073 and partially purified by galactosamine affinity chromatography and gel filtration chromatography based on its hemagglutination (HA) activity. The lectinlike substance was purified about 256-fold as evaluated by its specific HA activity. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the partially purified lectinlike substance (PPL) produced a single protein band of large molecular weight when it was applied to the gel without the addition of beta-mercaptoethanol and heating. Chemical analysis showed that PPL contained 14.4 micrograms of hexose per 100 micrograms of protein and that it did not contain muramic acid, glucosamine, or 2,6-diaminopimelic acid, which are characteristic of peptidoglycans. The HA activity of PPL was inhibited by EDTA but restored by adding Ca2+. The HA activity was remarkably inhibited by sugars containing N-acetyl-D-galactosamine and D-galactose. These results indicate that the lectinlike substance on the E. corrodens cells is an essential factor for the adherence to host cells.  相似文献   
108.
Using the plasma membrane fraction isolated from rabbit liver (RLPM), we detected non-species specific IgG antibody against liver cell surface membrane in the sera from the patients with chronic liver diseases. The sea were treated with dithiothreitol and iodoacetamide, and absorbed with sufficient amount of actin isolated from rabbit striated muscles. The antibody was detected by incubation of RLPM with the treated and absorbed sera and subsequent determination of IgG bound to RLPM by 125I-staphylococcal protein A. It was found mainly in the patients with autoimmune hepatitis (12 of 28) and liver cirrhosis (eight of 24). It occurred more frequently in HBsAg negative liver cirrhosis than in HBsAg positive forms (six of 13 vs two of 11). The frequency of the antibody was low in chronic hepatitis except autoimmune hepatitis, and primary biliary cirrhosis. Thus the antibody against RLPM was an immunological marker of autoimmune hepatitis and HBsAg negative liver cirrhosis. The occurrence did not correlate with those of anti-smooth muscle antibody, anti-nuclear antibody and anti-mitochondrial antibody. In two cases of autoimmune hepatitis, the antibody against RLPM decreased with clinical improvement induced by corticosteroids.  相似文献   
109.
In the present study, small volumes of plasma were used for the measurement of bromvalerylurea (BVU), its metabolite, 3-methylbutyrylurea (MVU), and bromide in carbon tetrachloride (CCl4)-treated rats by HPLC-UV and energy dispersive X-ray spectrometry. A liquid-liquid extraction system was also investigated. BVU and MVU were extracted from 100 microl plasma samples in a single-step involving deproteination with 1 M hydrochloric acid using ethenzamide as internal standard. Samples were separated by HPLC in an acetonitrile-8 mM potassium dihydrogenphosphate buffer (35:65, v/v) mobile phase at a flow-rate of 0.4 ml/min on a 15 cm octadecylsilyl column at room temperature. Analytes were detected at a wavelength of 210 nm. The limits of quantitation for BVU, MVU and bromide are 0.1, 0.1 and 50 microg/ml, respectively. The intra-day accuracies over the range of concentrations were 95.8 to 121.1%, 97.2 to 119.7% and 96.2 to 105.8% for BVU, MVU and bromide, respectively. The inter-day accuracies were 97.7 to 115.1%, 98.3 to 111.6% and 98.3 to 102.9% for BVU, MVU and bromide, respectively. The absolute recoveries using tert.-butyl methyl ether are 96-98% for BVU and 95-98% for MVU. The decline in the plasma concentrations of BVU in olive oil-treated rats fitted a one-compartment model and the plasma MVU level reached a peak at around 1.5-2 h and then decreased gradually. The elimination of BVU in CCl4 (1 ml/kg)-treated rats was delayed and MVU production was less than that in the olive oil-treated group. However, there was no difference in the plasma levels of bromide between CCl4-treated rats and control rats. rights reserved.  相似文献   
110.
Very-long-chain acyl-CoA dehydrogenase (VLCAD) deficiency is clinically classified into severe, intermediate, and myopathic forms. We identified mutations in three unrelated Japanese patients with VLCAD deficiency: two with the myopathic form and one with the intermediate form, all compound heterozygotes of K264E/M437V, A416T/1798delA, and P89S/IVS16-3delAA, respectively. We characterized four missense mutations, K264E, M437V, A416T, and P89S, by transisent expression analysis, using SV40-transformed fibroblasts derived from a VLCAD-null patient, as recipient cells. In transient expression of the wild-type VLCAD cDNA, VLCAD activity at 30 degrees C was higher than at 37 degrees C. Moreover, this temperature-sensitive character is more evident in all the mutant proteins tested than in wild type. Based on characterization of the five missense mutations identified in four Japanese patients, including data on one patient with the myopathic form previously reported, patients with the nonsevere forms (intermediate or myopathic forms) have missense mutations with residual activities in at least one allele. Expression analysis at 30 degrees C may be more useful for evaluating these missense mutations, compared with that at 37 degrees C.  相似文献   
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