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61.
Summary Normal oesophagus specimens taken from 65 autopsy cases and surgical specimens from 127 oesophageal carcinoma cases were examined histopathologically to determine melanocyte incidence and distribution. Melanocytes were found in the epithelio-stromal junction in 7.7% of normal oesophagus specimens examined at autopsy, and in 29.9% of surgical cases with oesophageal carcinoma. Positive specimens in the latter groups, especially from pre-operatively irradiated individuals, showed a more remarkable increase of melanocytes than was evident in any of the normal oesophageal samples. There were no significant differences in incidence between males and females, or between age groups. In cases where the cancer invaded into deeper stroma, the melanocytes were mainly observed in the normal epithelium around the carcinomas. Epithelial and stromal elements of the melanotic mucosa commonly showed hyperplastic changes such as acanthosis or basal cell hyperplasia, and chronic oesophagitis. Melanocytes were observed most commonly in the lower part of the oesophagus, the site where malignant melanoma of the oesophagus, most often originates. These results strongly suggest that the melanocyte increase observed in areas of hyperplastic epithelium and chronic oesophagitis may play an important role as a precursor lesion for malignant melanoma in the oesophagus.  相似文献   
62.
We examined 12 Japanese patients with metaphyseal chondrodysplasia (MCD) for mutations in the ribonuclease mitochondrial RNA processing gene (RMRP), and identified four novel mutations in two patients with typical and atypical cartilage-hair hypoplasia (CHH), a form of MCD characterized by extra-skeletal manifestations including hypoplastic hair and defective immunity. A patient with typical CHH had a 17-bp duplication at +3 and a de novo 182G > A. The other patient with atypical CHH had a 17-bp insertion at -20 and a 218A > G. Expression analysis revealed that the allele with this insertion mutation in the promoter region silenced the gene. Spectrum analysis of the mutations and polymorphisms in RMRP showed marked difference between the Japanese and other ethnic groups. Such ethnic and phenotypic difference should be taken into account in mutation analysis of the gene.  相似文献   
63.
Summary Distal deletion of chromosome 1q has been reported in nearly 30 patients, all being associated with a deletion ranging from the 1q42 or q43 band to 1qter region. Here, we describe a girl with 1q terminal deletion resulting from an unbalancedde novo translocation t(1;D or G)(q44; p11), as revealed by the presence of a satellited feature and an NOR-stained region at the tip of 1q. We suggest that most of the phenotypic abnormalities seen in patients with 1q distal deletion are attributable to the monosomy for band 1q44.  相似文献   
64.
We describe a case of hepatocellular carcinoma in which a tumor embolus in the portal vein and 3 of 4 intrahepatic metastases were necrosed completely by Lipiodol transcatheter chemo-embolization (Lipiodol-TCE). Tumor emboli in the portal vein and intrahepatic metastases usually cannot be necrosed by conventional transcatheter chemo-embolization alone, because small nodules such as intrahepatic metastases and tumor emboli in the portal vein are supplied blood from the portal vein. However, in this case, Lipiodol-TCE was effective against tumor emboli in the portal vein and intrahepatic metastases. ACTA PATHOL JPN 38: 1363-1367, 1988.  相似文献   
65.
We present the case of a 69-years-old man who was admitted to hospital with multiple myeloma. IgG-kappa type monoclonal protein was detected in the serum. When we separated the serum obtained from blood sample of the patient and the lid of the collecting tube was opened, the patient's serum became gelled immediately. When the lid of the collecting tube remained closed, the patient's serum did not become gelled even at 4 degrees C. Moreover, the gelled serum of the patient did not resolve at 56 degrees C. Taken together, these results indicated that gel formation of the patient's serum may not be due to cryoglobulin. It was found that the pH of the patient's serum elevated to pH 8.0 quickly after exposed to air. It was also found that the patient's serum, but not the sera of other IgG-kappa multiple myeloma patients, became gelled as soon as PBS of pH 8.0 was added. These results highly suggest that the patient's serum becomes gelled at pH 8.0. However, the isoelectric focusing of isolated precipitation in the patient showed fractions around the pH 8.5-8.7 zone, which was different from the pH at which the precipitation began to form. We think that this may be the first report of a multiple myeloma patient whose serum becomes gelled after exposed to air.  相似文献   
66.
The cationic, ring-opening copolymerization of 1,6-anhydro-2,3,4-tri-O-benzyl-ß-D -glucopyranose with epichlorohydrin, 3,3-bis(chloromethyl)oxetane and 1,3-dioxolane was investigated with phosphorus pentafluoride as catalyst at low temperatures. Besides, copolymerization of 1,6-anhydro-2,3,4-tri-O-methyl-ß-D -glucopyranose with epichlorohydrin was studied. Structure and composition of the copolymers were determined by 1H and 13C NMR spectroscopy, indicating that copolymerization occurred in each combination of monomers. Number-average molecular weights of copolymers were in the range of 1 400 to 22 800. From the specific rotation and 13C NMR spectrum of copolymers, it was revealed that the ring-opening copolymerization of the benzylated 1,6-anhydro-glucopyranose with the cyclic monomers occurred in a stereoregular manner to give the C-1 carbon of glucose unit with α-configuration. Debenzylation of a copolymer prepared from 1,6-anhydro-2,3,4-tri-Obenzyl-ß-D -glucopyranose and 1,3-dioxolane gave a copolymer composed of free sugar units in the polymer main chain. Assignment of 13C NMR spectra of 2,3,4-tri-O-benzyl-ß-D -glucopyranan and of a copolymer of 1,6-anhydro-2,3,4-tri-O-benzyl-ß-ß-glucopyranose with 1,3-dioxolane was attempted.  相似文献   
67.
Human saliva chromogranin A (CgA) is clinically promising as a psychological stress marker. However, expression of CgA is poorly understood in humans, although salivary gland localization of CgA in other mammals, such as rodents and horses, has been demonstrated. In the present study, we investigated the expression and localization of CgA in the human submandibular gland (HSG) using various methods. CgA was consistently localized in serous and ductal cells in HSG, as detected by immunohistochemistry and in situhybridization. Reactivity was stronger in serous cells than in ductal cells. In addition, strong immunoreactivity for CgA was observed in the saliva matrix of ductal cavities. Western blotting gave one significant immunoreactive band of 68 kDa in the adrenal gland, HSG and saliva. Finally, CgA was detected in secretory granules of serous and ductal cells by immunoelectron microscopy. In conclusion, CgA in humans is produced by HSG and secreted into saliva.  相似文献   
68.
The question was asked whether a predicted envelope protein, considered to be processed from the polyprotein precursor encoded by the putative E2/NS1 region of the hepatitis C virus (HCV) genome, may be observed in HCV-infected humans. Two polyclonal antibodies against recombinant E2/NS1 proteins were prepared and their reactivity tested against liver extracts from HCV-infected patients by immunoblotting analysis. A band corresponding to a size of 44 kDa was detected in liver extracts from patients who were positive for the HCV-specific antibody anti-C100-3 but not in liver extracts from patients who did not have anti-C100-3 antibody. Additionally, no band was detected using preimmune sera or antisera which had been preabsorbed with recombinant E2/NS1 proteins. Deglycosylation studies demonstrated that the 44 kDa protein was a glycosylated form of a 38 kDa protein which corresponds to the predicted molecular weight of the putative E2/NS1 protein. These results suggest that the 44 kDa protein is a product of the E2/NS1 region. Frequent observation of the 44 kDa band in cases of chronic active hepatitis C suggests a correlation between the expression of this protein and the progression of hepatitis. © 1994 Wiley-Liss, Inc.  相似文献   
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