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71.
Background  Endoscopic resection is an adequate treatment for subgroups of patients with early gastric cancer. Endoscopic submucosal dissection (ESD) represents a recent advance and leads to good results when adequately indicated. There is great experience with this technique in Japan and it is gaining acceptance among Western endoscopists. We present the first gastric ESD series performed in Brazil. Methods  Patients with well-differentiated adenocarcinomas macroscopically classified as early cancer, less than 30 mm with no ulcer or scar, were included. ESD was performed with an insulated-tip knife and electrosurgical unit with endocut mode. Clinicopathological aspects and morbidity were evaluated. The study was approved by the local ethics committee and informed consent was obtained from all participant subjects. Results  From October 2005 to July 2007, 160 patients received surgical treatment for gastric cancer; 44 patients (27.5%) had early gastric cancer. In this latter group, 15 procedures (ESD) were performed in 12 patients. The mean size of the lesions was 16.8 mm. Almost half of the lesions were located in the proximal third of the stomach and the mean elapsed time for the procedure was 140 min. In 80% of the cases resection was en bloc and 80% of the resections were considered curative. We had three perforations, which were managed clinically, and no bleeding. Conclusion  When adequately indicated, ESD is a safe and feasible technique.  相似文献   
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One of the resistance mechanisms to folate-based thymidylate synthase (TS) inhibitors is the increase in TS activity in tumor cells. Human B lymphoblastoid cell line (W1L2) was made resistant to a lipophilic non-polyglutamatable TS inhibitor (ZM249148), and the subline (W1L2:R179) showed a 20-fold increase in TS enzyme activity with concomitant overexpression of TS mRNA. To overcome the resistance, we designed a ribozyme that can cleave the CUC sequences in a triple tandemly repeated sequence of TS mRNA. Expression of this ribozyme in W1L2:R179 cells transfected with Epstein Barr virus-based expression vector resulted in sensitization to TS inhibitors concomitantly with a decrease of TS expression. The ribozyme expressed in transfectants was shown to be functional in cleaving artificial TS RNA in vitro.  相似文献   
74.
OBJECTIVE: Our study was undertaken to determine whether increased platelet activation occurs in patients with obstructive sleep apnea syndrome (OSAS) and whether a therapy with nasal-continuous positive airway pressure (N-CPAP) alters this activation. METHODS: We measured the positive rate of activated platelets using activation-dependent monoclonal antibodies (MoAb) and flow cytometry in whole blood from 94 patients with OSAS, and from 31 age-matched controls. Thrombotic vascular diseases were surveyed as a background of alternative of platelet activation. RESULTS: The positive rate for activated platelets was significantly higher in patients with OSAS ( PAC1 52.6 +/- 22.9 %, CD62P 6.8 +/- 7.1%, mean +/- SD), as compared with healthy control subjects ( PAC1 16.7 +/- 8.6 %, CD62P 0.7 +/- 0.5 %, p < 0.001). The activation indexes were significantly reduced after 1 month with N-CPAP treatment as a whole (PAC1; from 52.6 +/- 22.9 to 44.2 +/- 22.4, p < 0.05, CD62P; from 6.8 +/- 7.1 to 5.3 +/- 5.5, p < 0.05). In nearly 60 % of patients, platelets activation remained high despite significant improvement of sleep apnea-episodes after N-CPAP. These patients had significantly higher incidence of previous myocardial infarction and/or cerebral infarction and abnormalities of head MRI and carotid sonograpy; indicating that the platelet activation appears to be induced by existing atheroma plaque and not by sympathetic activity in OSAS. CONCLUSION: In conclusion, patients with OSAS have increased percentages of activated platelets as assessed by flow cytometrical analysis of activation dependent surface markers, and were divided into two groups, one group with response to N-CPAP treatment in the reduction of platelet activation and the other without. One possible reason of no response to N-CPAP treatment in the reduction of platelet activation was suggested to be thrombotic diseases.  相似文献   
75.
The relationship between infection with the Borna Disease Virus (BDV) and the clinical symptoms of schizophrenia and mood disorders (DMS-IV) was investigated. Western blotting techniques were used to examine anti-p10-BDV antibodies in serum from 32 patients with schizophrenia and 33 patients with mood disorders in Japan. The results showed that 1 out of 25 controls (4.0%), 7 out of 32 patients with schizophrenia (21.9%) and 9 out of 33 patients with mood disorders (27.3%) were positive for anti-BDV-p10 antibodies. Compared with levels of anti-BDV-p10 antibodies in controls, the production of anti-BDV-p10 antibodies failed to show a statistically significant relationship with schizophrenia but did show a significant relationship with mood disorder. The subgroup of schizophrenia patients with positive syndromes had a non-significantly higher frequency of anti-BDV-p10 antibodies than the subgroup of patients with negative syndromes. Similarly, the production of anti-BDV-p10 antibodies was non-significantly higher among patients with the unipolar subtype of mood disorder than in those with the bipolar subtype.  相似文献   
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This report presents a case of endometrioid adenocarcinoma arising from endometriosis of the mesenterium of the sigmoid colon following total abdominal hysterectomy and bilateral salpingo-oophorectomy for leiomyoma of the uterus and infiltrating pelvic endometriosis, and hormone replacement therapy. A 62-year-old woman presented with an abdominal tumor. Based on the diagnosis of mesocolonic tumor, sigmoidectomy with lymph node resection was performed. The tumor cells were immunopositive for cytokeratin 7, but negative for cytokeratin 20, and the tumor was histologically diagnosed as endometrioid adenocarcinoma of the mesocolon. Hyperestrogenism has been implicated as a risk factor for the development of cancer from endometriosis. The patient had been receiving high-dose unopposed estrogens for 14 years after a total abdominal hysterectomy and bilateral salpingo-oophorectomy. Physicians should recognize that endometriosis-associated neoplasms are able to cause symptoms or signs such as abdominal and/or pelvic pain, pelvic mass, and vaginal bleeding, especially if the patient has been treated with hormone replacement therapy. It is important to recognize the possibility of tumors arising from endometriosis when evaluating intestinal or mesenteric neoplasms in women, even in the patient who has previously undergone total abdominal hysterectomy and bilateral salpingo-oophorectomy, particularly if the patient has a history of endometriosis and has received hormone replacement therapy.  相似文献   
78.
A 50-year-old woman presented with rare multiple dissecting aneurysms that appeared first in the anterior cerebral artery (ACA) and shortly afterwards in the vertebral artery (VA). She initially suffered sudden motor weakness in the left lower limb due to acute brain infarction. Angiography revealed diffuse string sign in the right ACA. Conservative treatment resulted in resolution of the deficits. Follow-up angiography performed 1 year later revealed recovery of the ACA stenosis. Fourteen days later, she complained of sudden headache and became comatose. Computed tomography showed diffuse subarachnoid hemorrhage. Angiography revealed a new right VA dissecting aneurysm involving the posterior inferior cerebellar artery (PICA). The orifice of the dissection was not apparent in the operative field and the dissection extended to the median. The patient underwent extracranial right VA ligation, clipping of the proximal PICA, and revascularization between the right occipital artery and distal PICA. Her postoperative course was uneventful and she was discharged without neurological deficits. VA dissecting aneurysms involving the PICA without evident orifice or extending over the median can be treated by extracranial ligation with clipping of the PICA, followed by revascularization.  相似文献   
79.
The association of clubbing with miscellaneous diseases and its diagnostic implications are such that its detection should prompt consideration of the underlying etiology. We encountered a 48-year-old woman with clubbed fingers and a cauliflower-like gingival swelling on the hard palate of the upper jaw. There were no conventionally well-known causes for clubbing. Histological examination of gum biopsy specimen revealed a diagnosis of inflammatory gingival hyperplasia. As an etiology of clubbed fingers, gingivitis was suggested, since clubbing was regressed in parallel with remission of the gingivitis after the treatment by extraction of anterior teeth. Possible involvement of an autoimmune process in the pathogenesis was also considered, because of concomitant elevation of serum anti-double strand DNA antibodies. We recommend examination of the oral cavity for search of an inflammatory disease in cases with clubbed fingers, particularly when other common causes are not apparent.  相似文献   
80.
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