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171.
Dissection of the sinus of Valsalva is an extremely rare accident during percutaneous coronary intervention (PCI), but it can lead to serious complications such as dissection of the ascending aorta. We experienced a localized dissection of the right coronary cusp without coronary artery involvement that was induced by a guiding catheter during PCI in a patient with acute myocardial infarction. The localized dissection showed pooling of the contrast medium in the acute phase, but it subsided spontaneously after 12 days without any sequelae. Manipulation of the guiding catheter should be performed with great caution not only in the coronary artery but also in the sinus of Valsalva.  相似文献   
172.
Summary The effects of -difluoromethylornithine (DFMO), radiation and the therapy of their combination were investigated in rats bearing G-XII glioma. DFMO treatment as well as radiation therapy prolonged the survival period when compared to the results in non-treated control rats. The combination therapy showed a greater effect on the survival rate than the single therapies, the effect being additive. The concentration of putrescine, spermidine, andN 1-acetylspermidine in tumor tissues was lowered by DFMO, while that of spermine was slightly elevated. Radiation decreased the concentration of all the polyamines, putrescine, spermidine, spermine andN 1-acetylspermidine. The concomitant treatment with DFMO and radiation further decreased the concentrations of putrescine andN 1-acetylspermidine in tumor tissues. The survival period of glioma-bearing rats is inversely correlated with the tissue levels of putrescine plusN 1-acetylspermidine.Abbreviations DFMO -difluoromethylornithine - BrdUrd bromodeoxyuridine  相似文献   
173.

Background

Endoscopic resection is recommended for rectal neuroendocrine tumors <?1 cm in diameter; the three techniques (mucosal resection, submucosal dissection, and mucosal resection with variceal ligation device) of endoscopic resection of neuroendocrine tumor were reported; however, the optimal endoscopic technique remains unclear.

Purpose

We compared the efficacy and safety of three endoscopic rectal neuroendocrine tumor resection methods.

Methods

We retrospectively enrolled 52 patients with rectal neuroendocrine tumors treated by endoscopy at Aichi Medical University Hospital and Nagoya City University Hospital between May 2003 and June 2017. We compared clinical outcomes in three groups based on the endoscopic treatment method.

Results

Fifty-two patients underwent endoscopic rectal neuroendocrine tumor treatment (mucosal resection, 14; submucosal dissection, 19; mucosal resection with an endoscopic variceal ligation device, 19). In the endoscopic mucosal resection, submucosal dissection, and mucosal resection with variceal ligation device groups, R0 resection occurred in 50.0, 94.7, and 89.5%, respectively (mucosal resection vs. mucosal resection with variceal ligation device, p <?0.05; mucosal resection vs. submucosal dissection, p <?0.01), while the median procedure times were 6.5, 43, and 6.0 min, respectively (submucosal dissection vs. mucosal resection with variceal ligation device procedure times, p?<?0.01; mucosal resection vs. submucosal resection procedure times, p <?0.01). Postoperative bleeding occurred after endoscopic mucosal resection (1/14) and endoscopic submucosal dissection (4/19), but not after endoscopic mucosal resection with a ligation device.

Conclusion

Endoscopic mucosal resection with an endoscopic variceal ligation device was a safe, effective treatment for rectal neuroendocrine tumors.
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PURPOSE: The developmental process of serrated adenomas is obscure, and the importance of genetic alterations has not been elucidated clearly. The possibility that the developmental process and genetic alterations of serrated adenomas could differ from those of ordinary tubular adenomas was explored in this work. METHODS: Serrated adenomas were obtained by endoscopic resection (n = 57) and divided into two groups: flat (n = 10) and nodular (n = 47). Mutation of the K-ras gene was analyzed by enriched polymerase chain reaction–enzyme-linked mini-sequence assay, which can detect not only the presence of a mutation but also the mutation type of K-ras codon 12 with high sensitivity. Methylation-specific polymerase chain reaction was performed with specific primers for the DNA repair gene O6-methylguanine-DNA methyltransferase. RESULTS: Serrated adenomas located in the rectum were more likely to have a K-ras mutation (9/12, 75 percent), whereas serrated adenomas of the flat type were less likely to have one (1/10, 10 percent). Furthermore, nodular serrated adenomas that occurred in the rectum possessed a high frequency of K-ras gene codon 12 point mutation (8/10, 80 percent) despite an overall frequency of 46.8 percent (22/47). A mutation of the K-ras codon 12 gene was detected in 23 (40.4 percent) of 57 serrated adenomas. Three types of point mutations of codon 12 were detected, with the mutation of GAT being observed most frequently. CONCLUSIONS: This study shows that development of nodular serrated adenomas may depend on the mutation of the K-ras codon 12 gene, whereas development of flat serrated adenomas may not. Additionally, serrated adenomas that occur in the rectum are closely related to the mutation of the K-ras codon 12 gene. K-ras mutations in serrated adenomas may be unaffected by the epigenetic silencing of O6-methylguanine-DNA methyltransferase by promoter hypermethylation.  相似文献   
176.
We endoscopically measured pressures of the pancreatic duct (PP) and the sphincter of Oddi (SO) in patients with alcoholic (ALCP, n = 10), gallstone-associated (GSCP, n = 7), and idiopathic chronic pancreatitis (ICP, n = 21), and in 20 controls. The PP was significantly higher in the patients with ALCP (55.7 +/- 28.9 mm Hg), GSCP (33.6 +/- 16.2 mm Hg), or ICP (44.5 +/- 25.8 mm Hg) than in the controls (16.2 +/- 8.7 mm Hg), but there was no significant difference between ALCP, GSCP, and ICP. There was no significant difference between control subjects and ICP in the motility of SO. In ICP, there was no correlation between the PP and the motility of SO. In ALCP and GSCP, the frequencies of the papillary sphincter waves were significantly higher than in normal subjects, and there were correlations between the PP and the motility of SO. These data suggest that increased pancreatic ductal pressure in GSCP with papillitis or ALCP may be due in part to papillary dysfunction, but not in ICP.  相似文献   
177.
Summary We report on a patient with splenic lymphoma of B-cell origin who developed autoimmune hemolytic anemia (AIHA). IgM M-protein, IgM anticardiolipin antibody (ACA), and lupus anticoagulant (LA) were detected in the serum, and direct Coombs' test showed autoantibodies of the IgG1 and IgG2 subclasses on red blood cells (RBC). In in vitro culture, tumor cells isolated from the spleen produced only IgM ACA, which was enhanced by IL-6 but not by IL-4 or IL-5. The levels of ACA and LA decreased after splenectomy and chemotherapy; the strength of the direct Coombs' test, however, did not change. These findings indicated that in this patient the lymphoma cells produced IgM. ACA, but not autoantibodies of the IgG1 and IgG2 subclasses against RBC. It was also suggested that IL-6 might at least partially stimulate the production of ACA.  相似文献   
178.
A fractionated pancreatic antigen was prepared using a monoclonal antibody, SP3-1, which reacts with the duct cells of various exocrine organs. The cell-mediated immune response to this antigen was studied by the leukocyte migration inhibition test (LMT) in patients with chronic pancreatitis (CP), Sj?gren's syndrome (SjS), and chronic sialoadenitis (CSA). The migration index (MI) for the LMT was 0.97 +/- 0.07 in normal controls (mean +/- SD, n = 11, range: 0.88-1.08). A positive LMT result (MI less than 0.82 = mean -2 SD in controls) was obtained in 7/8 (88%) SjS patients, 4/22 (18%) CP patients, 2/3 CP patients with SjS, and 0/3 CSA patients. These results indicated sensitization against the pancreatic antigen in most SjS patients and some CP patients, and may suggest that an immune response to a common antigenic determinant of the duct cells of exocrine glands plays a role in the pathophysiology of both diseases.  相似文献   
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