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1.
This is the second reported case of a malignant fibrous histiocytoma of the heart that metastasized to the brain. A 33-year-old woman developed headache, nausea, and ataxic gait 9 months after removal of the tumor from the left atrium of the heart. Computed tomographic and magnetic resonance imaging scans disclosed multiple metastatic tumors in the brain. Although dramatic improvement in her symptoms and signs followed the removal of the brain tumors, she died of tumor recurrence in the left atrium 3 months after the removal of the metastatic brain tumors.  相似文献   
2.
Although the glucocorticoid receptor (GR) facilitates the xenobiotic-induced expression of CYP2B in rodents, its role in the regulation of human CYP2B6 is unclear. In this report, the role of human GR in the regulation of CYP2B6 was evaluated using primary human hepatocytes and transfection assays with Huh7 cells. CYP2B6 expression was not induced in primary hepatocytes treated with dexamethasone (DEX) concentrations (0.01-1 microM) known to activate GR. In contrast, treatment with 0.1 microM DEX enhanced CYP2B6 induction by different pregnane X receptor (PXR) activators, including rifampin, phenytoin, clotrimazole, and phenobarbital. In Huh7 cells, cotransfection of human (h)GR and hPXR with CYP2B6-phenobarbital-responsive enhancer module (PBREM) reporter constructs revealed that all hPXR ligands induce CYP2B6 reporter gene activity, and this ligand-dependent activation is greatly enhanced by activated hGR. CYP2B6 reporter gene expression was not induced in the presence of hPXR ligands when hGR alone was cotransfected with CYP2B6 reporter construct. In hGR and human constitutive androstane receptor (hCAR) cotransfection assays, activated hGR increased the constitutive activation of PBREM reporter constructs by hCAR in the absence of inducers. In the presence of activated hGR and known inducers of CYP2B6, only PB treatment caused a further 2-fold activation of hCAR compared with control. These studies show that hGR is involved synergistically in the xenobiotic-responsive regulation of human CYP2B6 by hPXR and hCAR. Moreover, the results suggest that the GR-enhanced expression of CYP2B6 is mediated through an indirect mechanism that does not require increased expression of nuclear receptor.  相似文献   
3.
Objective: The purpose of this experimental study was to investigate whether aortic stent grafting can be applied to the treatment of an esophageal cancer involving the thoracic aorta. Methods: The canine thoracic aorta was partially resected without aorta being clamped after emplacement of an endovascular stent graft. Study I; The aortic whole layer of 1 cm in length and 1/4 of the circumference was resected and was covered by a free fascia patch of the abdominal rectal muscle immediately after stent graft placement. Study II; The aortic adventitia and the outer half of the media of the same size was resected on day 3, 7,14, 21, and on day 28, after the stent graft placement. The resected portion was covered by the free fascia patch in half experimental dogs, and was uncovered in the others. Study III; The aortic adventitia and the outer half of the media of 1 cm in length and 1/2 of the circumference was resected and was uncovered on day 7 after stent graft placement. Histological examinations were performed on day 28 and at one year after aortic resection. Results: The aortic wall could be resected in all cases with no complication, except in resection of 1/2 the circumference where the aorta had become narrow. There was no difference in healing of the resected portion of the aorta between with and without fascia covering. Conclusion: An aortic endovascular stent graft could be applied to surgery for an esophageal cancer involving the aorta.  相似文献   
4.
Effects of the number of transplanted bone marrow cells and splenectomy performed before the transplantation on delayed type graft-versus-host disease (GVHD) were investigated in mice. The relation between delayed type GVHD and suppressor cells was also studied. Bone marrow cells (1 x 10(5)-1 x 10(7) cells) from CBA/N mice were transplanted to lethally irradiated (10 Gy) C57BL/6 mice, and the same type of transplantation was performed in other mice that underwent splenectomy. Suppressive effects of spleen cells from chimera mouse were measured by the percentage of suppression against alloantigen specific mixed lymphocyte reaction (MLR). The survival rate decreased with the number of grafted cells. However, survival rate was high in the splenectomy group even when the number of grafted cells was small. The incidence of delayed type GVHD was 0% in the 1 x 10(7) cell transplanted group, but that was more than 50% in the 1 x 10(5) cell transplanted group. There was no significant difference in the incidence of delayed type GVHD between the splenectomy group and non-splenectomy group. Spleen cells from chimera mouse without delayed type GVHD had greater suppressive effect against MLR than those with GVHD. These results suggest that alloantigen specific suppressor cells in the spleen of chimera mice inhibit delayed type GVHD.  相似文献   
5.
6.
To investigate the adequate extent of esophagectomy and lymphadenectomy for an esophageal cancer localized at the cervicothoracic junction, the mortality and morbidity rates, survival rates, and patterns of recurrence were retrospectively analyzed in two groups—14 patients who underwent total esophagectomy with or without laryngectomy and 15 patients who underwent proximal esophagectomy with or without laryngectomy—at Kurume University Hospital from 1981 to 1996. Proximal esophagectomy with or without laryngectomy resulted in a lower hospital mortality rate and better overall survival for patients who underwent curative esophagectomy compared with total esophagectomy with or without laryngectomy. Multivariate analysis indicated that the extent of esophagectomy (total esophagectomy versus proximal esophagectomy) was not a prognostic factor. The incidence of recurrence was not different between the two groups. Lymph node metastasis or recurrence from such esophageal cancers was localized to the neck and upper mediastinum. For an esophageal cancer localized at the cervicothoracic junction, therefore, proximal esophagectomy with or without laryngectomy and with cervical and upper mediastinal lymphadenectomy could be better indicated for preselected patients.  相似文献   
7.
8.
Serial changes in N-isopropyl-p[125I]-iodoamphetamine (125I-IMP) in mouse lungs were observed with a confocal laser scanning microscope. Male mice were intravenously injected with 125I-IMP and subjected to autoradiographic procedures 20 minutes, and 3 and 24 hours after injection. Differential interference contrast (DIC) images and confocal images were obtained with a confocal laser scanning microscope, and superimposed images were evaluated. Large numbers of silver grains were observed in the interstitium, bronchioles, and alveolar sacs 20 minutes after the injection, and lamellar distribution of the grains was observed on the ciliary surface. The numbers of silver grains in the interstitium and bronchioles had decreased 3 hours after the injection of 125I-IMP, but the numbers of silver grains in the alveolar spaces had not. Although small numbers of silver grains remained in both the bronchioles and alveolar sacs 24 hours after the injection, most of them had washed out. Confocal laser scanning microscopy is considered to be a useful procedure for studying the distribution of radioisotopes by microautoradiography, because it allows clear autoradiographs to be obtained in which tissues and silver grains are perfectly matched and all silver grains are in focus.  相似文献   
9.
PURPOSE: The purpose of this work was to assess the scan delay and the effect of flow rates on arterial phase scanning of hepatic CT. METHOD: One hundred twenty patients suspected of having hepatocellular carcinoma were examined by three-phase helical CT using computer-assisted bolus-tracking technology. We set the region of interest (ROI) in the abdominal aorta at the level of the celiac artery as a baseline. The triggering threshold was set at 100 HU. A volume of 100 ml of iomeprol (350 mg of I/ml) was administered at 2, 2.5, or 3 ml/s i.v. RESULTS: In all cases, helical CT scanning began after reaching the ROI threshold. Then, portal venous phase scanning was initiated 50 s after arterial phase initiation. The mean delay time from the initiation of contrast agent administration to the beginning of arterial phase scanning was 29.2 +/- 3.8 s (mean +/- SD, range 22-39 s). A faster injection rate significantly shortened the scan delay (p < 0.01). In portal venous phase scanning, calculated areas under the hepatic enhancement curves were almost equal among different injection rates. CONCLUSION: The computer-assisted bolus-tracking technology is a useful method for determining an individual scan delay of arterial phase CT.  相似文献   
10.
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