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61.
A 57-year-old man with a history of renal cell carcinoma presented with presyncope. He underwent nephrectomy years earlier followed by HLA-matched allogeneic peripheral-blood stem-cell transplantation. Echocardiographic investigation revealed a solitary right ventricle mass without contiguous vena caval or right atrial involvement. The mass was pathologically confirmed to be metastatic carcinoma in the right ventricular cavity. This case highlights the need to consider an underlying neoplastic syndrome in patients presenting isolated right ventricle mass by echocardiography.  相似文献   
62.
The goal of endoscopic mucosal resection (EMR) is to allow the endoscopist to obtain tissue or resect lesions not previously amenable to standard biopsy or excisional techniques and to remove malignant lesions without open surgery. In this article, we describe the results of conventional EMR and EMR using an insulation‐tipped (IT) electrosurgical knife (submucosal dissection method) for large colorectal mucosal neoplasms and discuss the problems and future prospects of these procedures. At present, conventional EMR is much more feasible than EMR using IT‐knife from the perspectives of time, money, complication, and organ preservation. However, larger lesions tend to be resected in a piecemeal fashion; and it is difficult to confirm whether EMR has been complete. For accurate histopathological assessment of the resected specimen en bloc EMR is desirable although further experience is needed to establish its safety and efficacy. Further improvements of in EMR with special knife techniques are required to simply and safely remove large colorectal neoplasms.  相似文献   
63.
Abstract: A cell line, BAD05, derived from B lymphocytes of an adenosine deaminase (ADA; EC 3,5,4,4)-deficient patient could not proliferate in a serum-free medium containing 100 μmol/l deoxyadenosine. When BAD05 was cultured with ADA-positive fibroblasts, the proliferation of BAD05 was improved. BAD05 cell density increased when the initially mixed ratio of fibroblasts/BAD05 was 1/10 or higher, but decreased when the ratio was 1/20 or lower. Deoxyadenosine concentrations in the medium and ATP and deoxyATP (dATP) levels in the BAD05 were measured after 4 hours of coculture at initial BAD05 cell densities of 1 × 105and 1 × 106cells/ml. Deoxyadenosine concentrations in the medium decreased as the density of fibroblasts increased. The dATP level decreased as the mixed ratio rose. The ratio of fibroblasts/BAD05 rather than the cell density of fibroblasts had a larger effect on the dATP levels in BAD05. Under our experimental conditions, ADA-negative cells proliferated well when the ratio of ADA-positive cells/ADA-negative cells was over 1/10.  相似文献   
64.
Primary leiomyosarcoma of the thyroid gland   总被引:1,自引:0,他引:1  
Primary leiomyosarcoma of the thyroid gland is extremely rare, and to the best of our knowledge only five well-documented cases have been reported in the world literature. We herein report a 58-year-old female patient with primary leiomyosarcoma of the thyroid who was successfully treated by total thyroidectomy with a modified neck dissection. Immunohistochemically, the tumor cells showed positive reactivity to α-smooth muscle actin and vimentin. Radical surgery was thus considered to be essential in the treatment of this rare but rather aggressive malignancy.  相似文献   
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Helicobacter pylori (HP) has been shown to possibly be a pathogen of gastric carcinoma. HP has urease activity and produces ammonia in the stomach. In this study, the role of ammonia on gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) were investigated in rats. After 24 weeks pretreatment with MNNG (83 mg/l), 0.01% ammonia or tap water as a drinking water was administered for 24 weeks. The ammonia-treated rats showed a significantly higher incidence of gastric cancer (percent of animals with tumors and number of tumors per rat). Ammonia would thus appear to have an important role in HP-related human gastric carcinogenesis.  相似文献   
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69.
The patient was a 48-year-old male who was diagnosed with unstable angina. He had worsening cardiogenic shock during coronary angiography. Emergency coronary artery bypass grafting (CABG) was performed. He had a methicillin-resistant Staphylococcus aureus (MRSA) mediastinitis on day 22 after CABG. Drains were placed in the anterior mediastinum, left thoracic cavity, and abscess cavity, and another drain was placed in the mediastinal space for continuous cleansing with povidone iodine, oxydol. For antibiotics, teicoplanin (TEIC) was administered intravenously and to the local site via the cleansing drain for about one month. No MRSA was detected by culture in discharges from the mediastinal drain. Inflammatory findings were improved, and the patient was discharged and resumed everyday life without recurrence of inflammation as of eight months. Although the number of cases of MRSA mediastinitis is small and accumulation of cases is necessary to investigate therapeutic methods and selection of antibiotics, our department will select closed continuous cleansing and TEIC for antibiotics as the first choice for MRSA mediastinitis, and accumulate cases to investigate its efficacy.  相似文献   
70.
Summary We recorded visual evoked potentials (VEPs) elicited with high or low imaginable Chinese characters (HIC or LIC), representing concrete objects or absolute concepts, respectively. A closed circle (CC) acts as control stimulus. These were displayed (at 1.6° visual angle) for 35 ms on a TV monitor. Twenty-one channel VEPs (band-pas filter: 0.05–60 Hz), using balanced non-cephalic electrodes, were recorded from –100 to 924 ms for 11 right-handed male volunteers. The VEPs were analyzed by multivariate analysis of variance (MANOVA) and comparison of topographies at four remarkable peaks (P110, N160, P230 and N320). MANOVA showed significant differences (p< 0.001) for both conditions of channel and stimuli (HIC, LIC or CC). P100 for the CC-VEPs, N160 for the HIC-and LIC-VEPs, P230 for the CC-VEPs, and N320 for the HIC-VEPs were remarkable in the posterior scalp regions. Topographies at P100 and N160 showed no difference between the HIC-and LIC-stimuli. However, those at N320 showed difference between the HIC-and LIC-stimuli over the occipital and posterior temporal areas. Those results suggest that the responses at P100 and N160 might segregate Chinese characters from non Chinese characters. N320 suggested certain processes in imagery on recognizing Chinese characters over the occipital and posterior temporal areas.We are grateful to Dr. Yoshiji Kojima of Hamamatsu University for helpful comments.  相似文献   
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