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11.
A case of renal angiomyolipoma with bone formation is reported. A 61-year-old woman was admitted to our hospital with one month history of fever. About 15 cm in diameter mass was palpated in her right lower abdomen. Plain abdominal roentgenography, ultrasonography and computed tomography showed marked calcification in the cephalic portion of the right kidney, tumors surrounding right kidney and another tumor in the right lower abdomen. All these tumors and the kidney constituted a big mass continuously, and no fatty component was demonstrated. Total excision of the mass including the kidney was performed. The mass was 30 X 24 X 10 cm in size and 3,240 g in weight. Histologically, the tumor was compatible to renal angiomyolipoma. But, radiopaque shadows which looked like calcification were disclosed to be bones, and fatty tissues were not seen so much. Therefore, the name "benign mesenchymoma" was thought to be more acceptable than angiomyolipoma in this case. Preoperative diagnosis of renal angiomyolipoma is the demonstration of fatty densities in the tumor, and the characteristic extrarenal development should also be taken into consideration. Furthermore, the bone formation of angiomyolipoma, which is very rare might be an important finding to angiomyolipoma.  相似文献   
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13.
Chromosome 1p36 deletion syndrome is characterized by hypotonia, moderate to severe developmental and growth retardation, and characteristic craniofacial dysmorphism. Muscle hypotonia and delayed motor development are almost constant features of the syndrome. We report a 4-year-old Japanese girl with 1p36 deletion syndrome whose muscle pathology showed congenital fiber type disproportion (CFTD) myopathy. This is the first case report of 1p36 deletion associated with CFTD. This association may indicate that one of the CFTD loci is located at 1p36. Ski proto-oncogene −/− mice have phenotypes that resemble some of the features observed in patients with 1p36 deletion syndrome. Because fluorescent in situ hybridization analysis revealed that the human SKI gene is deleted in our patient, some genes in 1p36, including SKI proto-oncogene, may be involved in muscle hypotonia and delayed motor development in this syndrome. Received: March 4, 2002 / Accepted: July 7, 2002  相似文献   
14.
A male case of Alagille's syndrome associated with a hamartomatous nodule of the liver is described. The patient developed jaundice soon after birth, and was diagnosed as the syndrome with signs such as paucity of the intrahepatic bile ducts, pulmonary stenosis and embryotoxon in the cornea at 15 years of age. The liver was examined in recurrent biopsies and other tests. However, no evidence of liver cirrhosis was confirmed until his 15th year. The patient died of hepatic dysfunction when he was 17 years old. At autopsy, a large hamartomatous nodule was found in the liver showing biliary cirrhosis. Morphology of the nodule resembled that of focal nodular hyperplasia. Abnormalities of the large vessels were noted around the liver. Vascular abnormalities were also seen in the mass. The relation of these vascular abnormalities to etiological background of the syndrome and occurrence of the nodular lesion is discussed.  相似文献   
15.
The influence of age and diet on the ultrastructure of hepatocytes is reported. The following dietary manipulations were investigated: Group 1, fed ad libitum a diet containing 21% protein; Group 2, fed a similar diet but restricted to 60% of the intake of Group 1 from 6 weeks of age onwards; Group 3, restricted from 6 weeks to 6 months of age and thereafter fed ad libitum; Group 4, restriction started at 6 months of age; Group 5, fed ad libitum a diet containing 12.6% protein. In all groups the size of hepatocytes was found not to increase during adult life. The size of hepatocytes in Groups 2 and 4 was the same as or larger than that of the other groups; thus food restriction resulted in a decreased number of hepatocytes. Changes in the structure of some organelles and the accumulation of lipofuscin granules occurred with advancing age and the extent of these age-related changes was less in Groups 2 and 4 than in the other groups. These morphologic findings in conjunction with our previously reported metabolic findings provide a new view of the action of food restriction on the aging process. ACTA PATHOL JPN 38: 1119∼1130, 1988.  相似文献   
16.
Recently developed immunohistochemical techniques are revolutionizing surgical pathology. Although much has been written describing sensitivity and specificity of reagents in the relationship to given diagnoses, little has been published regarding the evaluation in diagnostic histopathology. Of 4905 cases, immunohistochemical stains were done in our laboratory on 108 cases in 1988. Forty three markers of different kinds were used for 266 specimens. The mean number of markers used in one case was 2.5. Evaluation study of these cases revealed good to limited diagnostic value of immunohistochemical procedures in about 70% of those cases, but no diagnostic value in approximately 30% of the cases. Relationship between venous invasion and basement membrane was investigated to clarify the mechanism of liver metastasis of the colorectal carcinoma by histologically and immunohistochemically using the anti-laminin antibody. Ninety cases of colorectal carcinoma with liver metastasis were studied. Venous invasion was found in 60 of 66 cases of synchronous liver metastasis, and in 14 of 24 cases of metachronous liver metastasis. Venous invasion was considered highly significant to development of liver metastasis, though there was a definite difference in several aspects between the two groups. Well-defined laminin-containing basement membrane was found in the primary tumor in 35 of 90 cases and in metastatic foci in 15 of 28 cases in which examination was performed. It was most frequently seen in well differentiated adenocarcinoma, though statistically not significant compared to moderately differentiated adenocarcinoma. No definite correlation was found between development of liver metastasis and basement membrane associated tumor cells.  相似文献   
17.
Transmission electron microscopy of thin sections of the rat incisor pulp revealed that in the middle region of the incisor there were fenestrated capillaries in the “predentinal plexus” and that this region contained the tallest odontoblasts. The odontoblasts gradually became shortened in the incisal part of this region: the fenestrated capillaries in the predentinal plexus changed to continuous type capillaries. Almost all the odontoblasts had degenerated near the incisal end of the tooth. The predentinal plexus disappeared in this region, but the “subodontoblastic capillary plexus” persisted. In a specific region just beneath the worn incisal end, numerous macrophages and polymorphonuclear neutrophils appeared and scavenged the degenerating cells, possibly including the odontoblasts. © 1993 Wiley-Liss, Inc.  相似文献   
18.
Four types of lymphocyte chemotactic factor (LCF-a, -b, -c and -d) could be isolated from extract of 24-hr-old delayed-type hypersensitivity (DTH) skin reaction sites induced with purified protein derivative (PPD) in guinea-pigs by gel filtration on Sephadex G-100 followed by chromatography with DEAE-Sephadex. Partially purified LCF-b was thought to be a heat-stable protein with a molecular weight (mol. wt.) of about 14,000. LCF-c separated from LCF-d by chromatography with DEAE-Sephadex was highly purified by chromatography with CM-Sephadex, immunoadsorbent chromatography coupled with anti-IgG antibody, and chromatofocusing in that order. It was considered to be a heat-labile protein with a mol. wt. of about 160,000 and with pI of 8.1 +/- 0.2. LCF-d first separated from LCF-c was also highly purified by chromatography with CM-Sephadex followed by preparative isotachophoresis. The factor was considered to be a heat-labile protein with a mol. wt. of approximately 300,000 and with pI of 6.2 +/- 0.2. These factors were similarly active for non-adherent cells (mostly T cells) but not for cells (mostly B cells) adherent to anti-IgG antibody-coated petri-dishes. Since LCF-a was active for B cells as described earlier, it is thus suggested that LCF-b, LCF-c and LCF-d may be important for T cell migration in the DTH site to PPD.  相似文献   
19.
A new monoclonal antibody, PM-2K, was raised against 24-h cultured human peritoneal macrophages. Immunohistochemically, PM-2K recognized most tissue macrophages in lymphoreticular organs such as the thymus, spleen, lymph node, and tonsil. Kupffer cells of the liver, alveolar macrophages, and macrophages in the interstitial tissue of the kidney, pancreas, and many other organs were also positively labelled. On the other hand, PM-2K failed to recognize blood monocytes, freshly isolated peritoneal macrophages, microglial cells, osteoclasts, and dendritic cells such as Langerhans cells, interdigitating cells, and follicular dendritic cells. In various pathological conditions, PM-2K labelled a wide variety of proliferating macrophages. Reaction products of PM-2K were observed by immunoelectron microscopy on the cytoplasmic membrane of cultured peritoneal macrophages. The molecular weight of the antigen recognized by PM-2K was determined to be 150 kD by Western blotting. As no cells other than macrophages were reactive with PM-2K, this antibody is considered to be very useful not only in the investigation of macrophage differentiation and maturation, but also in the diagnosis of various proliferative disorders of macrophages.  相似文献   
20.
 We have already presented a two-dimensional cell motility assay using a highly metastatic variant (L-10) of human rectal adenocarcinoma cell line RCM-1 as a motility model of tumour cells of epithelial origin. In this model, L-10 cells showed locomotion as a coherent sheet when stimulated with 12-O-tetradecanoylphorbol-13-acetate (TPA), and we called this type of movement ”cohort migration”. Electron and immunoelectron microscopic study of the migrating cell sheets demonstrated localized release from cell–cell adhesion only at the lower portion of the cells with loss of E-cadherin immunoreactivity, and this change was associated with increased tyrosine phosphorylation of the E-cadherin–catenin complex, including β-catenin. Cell–extracellular matrix (ECM) interactions involved in this TPA-induced cohort migration and their effect on tyrosine phosphorylation of the E-cadherin-catenin complex have now been investigated. L-10 cell cohort migration was almost completely inhibited by addition of Arg-Gly-Asp (RGD) peptide into the medium, and thus RGD dependent. Cohort migration was stimulated on type I and IV collagens, fibronectin (FN)- and laminin-coated substratum, but was inhibited by RGD only on FN-coated surface. By using immunofluorescent techniques, FN was demonstrated preferentially around migrating cells, and a protein synthesis inhibitor, cycloheximide, inhibited the migration by about 75%. FN produced by L-10 cells were found to be mostly EDA+ FN when analysed by RT-PCR. Moreover, anti-FN antibody, but not anti-vitronectin antibody, inhibited the TPA-induced cohort migration almost completely. Thus, it was likely that L-10 cells produced FN themselves and moved on the FN substrate in an RGD-dependent manner. However, stimulation of migration by type I collagen coating and inhibition by RGD treatment did not affect the tyrosine phosphorylation of the E-cadherin–catenin complex induced by TPA, indicating that cell–cell interactions were adjusted to suit cell migration, irrespective of the condition of cell–ECM adhesion, during TPA-induced cohort migration. Received: 31 December 1997 / Accepted: 2 April 1998  相似文献   
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