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41.
42.
Abstract Background: Yolk sac tumors (YST) exhibit several different histological subtypes and the mechanisms of cellular differentiation and prognosis of each subtype remain unknown.
Results: We report two infants with sacrococcygeal YST; one represented a typical histological subtype and the other showed a hepatoid subtype with uniform histology. The isoform of alpha-fetoprotein (AFP) in the patient with the hepatoid pattern was examined by lectin-affinity Immunoelectrophoresis and represented as a YST. but not hepatocellular, subtype. The patient with typical YST responded well to VAB-6 combination chemotherapy. However, this regimen was only partially effective to the patient with the pure hepatoid histological subtype, and an etoposide with ifosfamide and cisplatin (VIP) regimen as a salvage chemotherapy combined with complete tumor resection was useful to achieve complete remission (CR). Both of the patients have been in CR for more than four years.  相似文献   
43.
Cells of the human tumor cell line RMG-1, derived from a clear-cell adenocarcinoma of the ovary, were injected intraperitoneally into nude mice, and the cells obtained from the tumor nodules in the mesenterium were found to form a larger number of, and larger-sized, tumor nodules than the original RMG-1 cells. The RMG-1-h cells, transferred into culture from the tumor nodules after a 4th in vivo passage, showed a dissemination potential as high as that of cells disseminating directly from the tissues, and exceedingly higher than that of RMG-1 cells. To assess the molecular bases of the different biological properties of RMG-1 and RMG-1-h cells, we compared the content and expression of various carbohydrate antigens in both cells. The chromosomal profile of RMG-1-h cells revealed their human origin and was identical to that of the original RMG-1 cells. In contrast to the broad histogram for the Lex-bearing cells among RMG-1 cells in flow cytometry, the weakly and moderately positive cells toward anti-Lex antibody were found to be eliminated from the histogram for the RMG-1-h cells, resulting in the enrichment of cells strongly expressing Lex, which may account for the high dissemination potential. In addition, the adhesion of RMG-1 cells to mesothelial cells was found to be significantly inhibited by pretreatment of the cells with anti-Lex antibody, indicating Lex-mediated cell-to-cell interaction between ovarian cancer cells and mesothelial cells. By TLC-immunostaining, two Lex-glycolipids, III3Fucα-nLc4Cer and V3Fucα-nLc6Cer were detected in both RMG-1 and RMG-1-h cells, and their total concentrations were not significantly different from each other. However, the hydrophobic moieties of Lex-glycolipids in RMG-1-h cells were different from those in RMG-1 cells, suggesting that a difference in the structure of the hydrophobic moieties of Lex is partly involved in the enhanced reactivity of RMG-1-h cells toward anti-Lex antibody. Thus, the high dissemination potential of ovarian cancer cells was shown to be mediated by the Lex-determinant and the Lex-bearing cells are enriched by repeated in vivo passage of the cells into nude mice.  相似文献   
44.
Abstract Background : Use of balloon angioplasty or stent implantation has been reported to be effective in relieving coarctation of the aorta. However, restenosis frequently occurs after balloon angioplasty for native aortic coarctation in small infants, and sometimes develops after stent implantation because of vessel growth. The causes of restenosis remain uncertain. The purpose of this study was to assess the histologic differences in vascular responses to angioplasty using conventional balloon, radiofrequency thermal balloon (RFTB), or stent for experimental aortic coarctation. Methods : The authors surgically created an aortic coarctation model using 14 puppies. Angioplasty using conventional balloon, RFTB, or stent was performed 1 month after the initial operation. At the acute or chronic phase after angioplasty, the animals were killed and histologic studies were performed. Results : More vascular injuries were noted in the specimens from animals undergoing conventional angioplasty than in those with RFTB or stent. However, neointimal hyperplasia was seen more often after RFTB or stent because of the proliferation of smooth muscle cells from the tunica media, caused by secretion of growth factors. Apoptosis reached a peak 1?2 weeks after angioplasty, regardless of the type of intervention. Conclusions : The authors conclude that angioplasty with RFTB or stent can provide relatively small injuries in the vessel wall for aortic coarctation, but care must be taken to prevent restenosis caused by intimal hyperplasia, because neointima hyperplasia is more frequent after RFTB or stent.  相似文献   
45.
Surgery Today - Postoperative pneumonia affects the length of stay and mortality after surgery in elderly patients with colorectal cancer (CRC). We aimed to determine the risk factors of...  相似文献   
46.
Mucinous cystadenoma of the appendix is a type of appendiceal mucocele and a rather rare condition usually found incidentally in the course of other abdominal surgery. A previous evaluation of 73 appendiceal mucoceles showed that this disease was often associated with adenocarcinoma and other epithelial atypia. This observation suggested that patients with mucinous cystadenoma of the appendix also have some underlying disorders. However, non-epithelial changes associated with appendiceal mucocele have not been reported so far. In this study, we presented for the first time a mucinous cystadenoma of the appendix associated with muscular and neuromatous hyperplasia.  相似文献   
47.
A 63-year-old man was referred to our institute for the treatment of squamous cell carcinoma of the upper lobe of his right lung. A right upper lobectomy of the lung was performed with a mediastinal lymph node dissection. The postoperative pathological examination of the dissected specimens revealed one of the superior mediastinal lymph nodes to be morbid with micrometastasis of occult thyroid cancer, while no node involvement was seen due to lung cancer. A right lobectomy of the thyroid gland with a modified radical neck dissection was done 4 years later after the confirmation of the absence of any recurrent sign of lung cancer. In the resected specimen, papillary thyroid microcarcinoma was observed with several intraglandular metastases and right regional lymph node involvement. Eight months later, a new primary lung cancer developed in the left lung, and a left upper lobectomy of the lung with a mediastinal lymph node dissection was performed. At that time, the absence of mediastinal lymph node metastasis from lung cancer or thyroid cancer was confirmed. Mediastinal lymph node involvement as the initial manifestation of occult thyroid cancer in surgical treatment for lung cancer is rare, but it is important to be aware of the possibility of incidentally detecting occult thyroid cancer in surgical dissections in this area for lung cancer. The appropriate surgical treatment should be determined while carefully considering the prognosis of the lung cancer as well as that of any coexisting malignancy.  相似文献   
48.
In August 1997, a 68-year-old man presented with right pelvic pain. Pelvic computed tomography (CT) and bone scintigraphy showed a huge tumor of the right iliac bone. No other lesion was detected, in spite of a high serum carcinoembryonic antigen level (CEA, 963ng/ml). In October 1997, the iliac bone tumor was widely resected, and thereafter was diagnosed to be a metastatic adenocarcinoma of unknown origin. After a resection, the serum CEA level dropped as low as 6.4ng/ml, but gradually went up to 80ng/ml in October 1999. Next, a lung tumor in the left upper lobe was detected by routine chest CT. In January 2000, a left upper lobectomy was performed, and based on not only the pathological findings but also on an immunohistochemical analysis for napsin A expression, the tumor was diagnosed to be lung adenocarcinoma. The histological and immunohistochemical findings in the previously resected bone lesion were completely compatible with those in the pulmonary tumor, which was finally regarded as M1 lung cancer. In October 2002, the patient was alive without any symptoms, although the serum CEA level was elevated again. We consider this case worthy of presentation because of its unique clinical course as well as the successful long-term survival after surgical treatment alone, for both the primary and metastatic lesions.  相似文献   
49.
A 42-year-old obese woman with a history of liver cirrhosis and diabetes mellitus was admitted because of chest pain. Coronary balloon angioplasty and stenting were performed on the left anterior descending artery (LAD), which was 90% stenotic. She developed moderate shock about 6h later, and about 15 h after the procedure, she died from excessive bleeding from the right femoral artery because of removal of the catheter sheath by herself. Autopsy disclosed haemorrhagic cardiac tamponade and extensive haemorrhage into the epicardial adipose tissue, however, neither coronary perforation nor myocardial rupture was recognized. Histological examination of the dilated coronary segment revealed extensive dissection with an eccentric intimal thickening and the disruption of the adventitia. It was thought to be the origin of the haemorrhage. Although coronary dissection is a well-known complication during cardiac catheterization procedures, this report describes a rare fatal case with delayed onset of shock due to coronary dissection caused by balloon angioplasty and stenting in the presence of eccentric hyperplasia of the vessel wall.  相似文献   
50.
The cerebellum is a crucial structure for cognitive function as well as motor control. Benign brain tumors such as schwannomas, meningiomas, and epidermoids tend to occur in the cerebellopontine angle cisterns and may cause compression of the posterior lateral cerebellum near the superior posterior fissure, where the eloquent area for cognitive function was recently identified. The present study examined cognitive impairment in patients with benign cerebellar tumors before and after surgical intervention in order to clarify the functional implications of this region in humans. Patients with cerebellar tumors showed deficits in psychomotor speed and working memory compared with healthy controls. Moreover, these impairments were more pronounced in patients with right cerebellar tumors. Functional magnetic resonance imaging during performance of a lure task also demonstrated that cerebellar tumors affected pattern separation or the ability to distinguish similar experiences of episodic memory or events with discrete, non-overlapping representations, which is one of the important cognitive functions related to the hippocampus. The present findings indicate that compression of the human posterior lateral cerebellum affects hippocampal memory function.  相似文献   
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