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41.
BACKGROUND: Cultures of human endometrial tissue are useful for analysing the mechanisms underlying the menstrual cycle. However, long-term culture of endometrial tissue is difficult in vitro. Xenotransplantation of normal human endometrial tissue into immunodeficient mice could allow prolonged survival of the transplanted tissues. METHODS: Proliferative-phase endometrial tissue samples from three women were transplanted into the subcutaneous space of ovariectomized, immunodeficient, non-obese diabetic (NOD)/severe combined immunodeficiency (SCID)/gammaC(null) (NOG) mice. The mice were treated with 17beta-estradiol (E2) for the first 14 days after transplantation, followed by E2 plus progesterone for the next 14 days. The transplants were investigated morphologically and immunohistochemically at various times after implantation. RESULTS: The transplanted tissues contained large numbers of small glands, pseudostratification of the nuclei and dense stroma after treatment with E2 alone. After treatment with E2 plus progesterone, subnuclear vacuolation, luminal secretion and decidualization of the stroma were observed. When the hormone treatment ceased, tissue destruction occurred and the transplants returned to the proliferative phase. Lymphocytes were identified immunohistochemically: the numbers of CD56-positive and CD16-negative cells increased significantly in the stroma during the late secretory phase (day 28). CONCLUSIONS: Human endometrial tissue transplanted into NOG mice showed similar histological changes to eutopic endometrial tissue during treatment with sex steroid hormones for 1 month. Moreover, lymphocytes were produced in the transplanted human endometrial tissue. This system represents a new experimental model of the human endometrium in vivo.  相似文献   
42.
DNA was extracted from formalin-fixed and paraffin-embedded tissues of 85 patients with pediatric malignant solid tumors which had been resected at surgery or obtained at autopsy during a 24-year period. The tumors examined included 25 rhabdomyosarcomas, 12 Wilms' tumors, 10 hepatoblastomas and 37 neuroblastoma group tumors. Neuroblastoma group tumors were subclassified into 25 neuroblastomas and 12 ganglioneuroblastomas among which 6 composite ganglioneuroblastomas were included. Sample blocks were selected from both tumors and normal tissues in the majority of cases. We were able to reliably detect N- and c-myc gene amplification in tumor DNA by dot blot-hybridization. The N-myc gene showed approximately from 3- to 500-fold amplification in 19 of 33 cases of stage IV neuroblastoma group tumor. All of these 33 patients had been intensively treated with chemotherapy and/or radiotherapy. The c-myc was amplified 8-fold in 1 case of rhabdomyosarcoma, but neither N-myc nor c-myc was amplified in any cases of Wilms' tumor or hepatoblastoma. We retrospectively examined the association among N-myc gene amplification, prognosis, and histologic subtype in 33 patients with stage IV neuroblastoma group tumors. The survival of the patients with N-myc gene amplification was shorter than that of the patients without amplification of N-myc (p less than 0.05). There was no significant difference in prognosis between the 2 histologic subtypes; neuroblastoma and ganglioneuroblastoma, and the cases of tumors with amplified N-myc showed shorter survivals for each subtype (p less than 0.05). In every case of neuroblastoma group tumor, the copy number of the N-myc gene was the same among primary site and multiple metastatic tumors, even when the lesions showed differences in histologic subtype like neuroblastoma and ganglioneuroblastoma.  相似文献   
43.
We report an autopsy case of mixed ductal-endocrine carcinoma of the pancreas presenting as gastrinoma with Zollinger-Ellison syndrome. A 38-year-old Japanese male was found to have Zollinger-Ellison syndrome and pancreatic gastrinoma, and gastrectomy and resection of the pancreatic tumor were performed. However, hypergastrinemia persisted, and the patient died of disseminated carcinomatosis at 62 years of age, 24 years after the onset of Zollinger-Ellison syndrome. At autopsy, the main tumor was present in the residual pancreas, and metastases were noted in many organs. In the pancreas and other organs, ductal and endocrine carcinoma areas were mixed and there was a gradual transition between the two. No acinar differentiation was noted. The ductal elements were positive for mucins and carcinoembryonic antigen but negative for neuroendocrine markers, while endocrine elements were positive for chromogranin A and synaptophysin and to a lesser extent for gastrin, but negative for mucins and carcinoembryonic antigen. The ductal elements comprised about 30% of the tumor cells, and endocrine elements 70%. According to the revised World Health Organization classification, our case was diagnosed as mixed ductal-endocrine carcinoma. Our case is rare because the tumor manifested as gastrinoma with Zollinger-Ellison syndrome and the patient survived for 24 years. To the best of our knowledge, no such case has been reported. Our case suggests that pancreatic endocrine tumors may evolve into mixed ductal-endocrine carcinomas. Received: 14 April 1999 / Accepted: 7 July 1999  相似文献   
44.
The presence of centromeric DNA was studied in micronuclei isolatedfrom the blood of male ddY mic after five weekly intraperitonealinjections of mitomycu C (MMC), 1-ß-D-arabinofuranosylcytosine(Ara-C), colchi cine (COL) or vinblastine sulfate (VBL). Inagreement with our earlier findings, about half of the micronucleiisolate* from vehicle control mice showed centromere signalsa analyzed by fluorescence in situ hybridization (FISH) witha mouse major (gamma) satellite DNA probe. In an earlie experimentwith mice acutely exposed to the same chem icals, the clastogensMMC and Ara-C did not reduce thi proportion of micronuclei withcentromere signals. In the present study, however, MMC and Ara-Cdecreased the proportion of micronuclei with centromeres. Incontrast the spindle poisons COL and VBL increased the proportionof micronuclei that contained centromeres. 3To whom correspondence should be addressed  相似文献   
45.
The effect of polyanions on the formation of mixed dimers of methylene blue ( 1 ) and trypaflavine ( 2 ), methylene blue ( 1 ) and phenosafranine ( 3 ), and methylene blue ( 1 ) and pyronine G ( 4 ) was investigated spectrophotometrically. The following polyanions were used: poly(potassium styrenesulfonate) (PSS), poly(potassium vinyl sulfate) (PVS), and poly(sodium acrylate) (PAA). On addition of polyanions, the formation of mixed dimers was enhanced largely. Thermodynamic parameters inferred that the enhancement of the formation of mixed dimers in the presence of polyanions resulted from an entropic factor.  相似文献   
46.
The structural effect of polyanions on the binding type of methylene blue ( 1 ) was investigated spectrophotometrically. 1 was bound to poly(potassium styrenesulfonate) (PSS) and poly(sodium 4-vinylphenylsulfate) (SVS) in the dimeric or slightly aggregated form and to poly(sodium vinylsulfonate) (SVF) and poly(potassium vinyl sulfate) (PVS) in the highly aggregated (polymeric) form. It was found that the flexibility of polyanions plays an important rǒle in the aggregation of bound 1 and that the difference between ? SO and ? OSO as binding site is not a significant factor.  相似文献   
47.
We performed molecular analysis of a germline interstitial deletion of chromosome 4 [del(4)(q21.22q23)], which had been observed in a male infant manifesting early-onset hepatoblastoma (HBL). The chromosomal anomaly in this child was associated with a unique congenital syndrome including HBL, atrial septal defect, ventricular septal defect, patent ductus arteriosus, mental retardation, and seizures. However, the patient did not exhibit a megalencephaly typical of 4q21-22 deletions. His HBL was associated with an increasing serum alpha-fetoprotein level and rapid growth. To define the chromosomal deletion at the molecular level in this child, we analyzed his lymphoblasts with fluorescence in situ hybridization, using as probes a panel of BAC/PAC genomic clones containing STS markers covering the 4q12-27 region. The analysis revealed that the affected chromosome had an 8-cM deletion within 4q21-q22, flanked by markers D4S2964 and D4S2966. This microdeletion overlaps with the commonly deleted region at 4q21-q22 that was recently defined in adult hepatocellular carcinomas.  相似文献   
48.
A 69-year-old man in whom idiopathic enlargement of the right atrium was revealed at autopsy is described. The patient had had cardiomegaly of at least 19 years' duration prior to his death, even though cardiac symptoms were absent. Cause of death was pancreatic carcinoma. Postmortem examination revealed marked and diffuse dilatation of the right atrium and moderate dilatation of the left atrium. Measurement of the cardiac chambers showed that the right and left atria were 7.6 and 4.7 times as large as those of normal hearts, respectively. The volume of either ventricle was about twice the normal value. Histologically, widespread cardiac muscular degeneration and necrosis, diffuse fibrosis, and focal lymphocytic infiltration were found in the right atrium and also, to a lesser degree, in the left atrium. Such pathologic changes were not found in either of the ventricles. The etiology of these muscular changes, which might have been related to atrial enlargement, was unclear. The present case was thought to be consistent with idiopathic enlargement of the right atrium, and a brief review of the literature is given.  相似文献   
49.
Carcinoma arising from Rokitansky–Aschoff sinus (RAS) is extremely rare; only eight cases have been reported in the literature. Herein is reported a case of minute adenocarcinoma arising in RAS. A 77‐year‐old Japanese man with gallbladder stones underwent cholecystectomy. A tiny submucosal tumor (1 cm × 1 cm) was incidentally recognized. Histologically, the submucosal tumor was located in the subserosa and, to a lesser extent, in the fibromuscular layer. It was adenocarcinoma. RAS were recognized within the tumor, and there was a gradual transition between RAS and the adenocarcinoma. Mucin histochemistry indicated neutral and acidic mucins in the cytoplasm and lumens of the adenocarcinoma cells. Immunohistochemistry showed that the adenocarcinoma cells were positive for cytokeratin, epithelial membrane antigen, carbohydrate antigen 19‐9, K‐i67 (labeling = 80%), MUC1, MUC5AC and MUC6. In contrast, the adenocarcinoma cells were negative for CEA, c‐erbB2, p53 protein, MUC2 and CD10. In summary, minute subserosal adenocarcinoma, which arose in RAS, was found incidentally; therefore careful examination of resected gallbladders is necessary.  相似文献   
50.
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