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Few studies have reviewed the roles of perfusion magnetic resonance (MR) imaging in the histopathological examination of meningiomas. We analyzed the relationships between radiological findings on perfusion MR imaging and pathological characteristics such as origin of the tumor, mitotic activity, pathological subtype, and perifocal edema formation. The subjects were 21 surgical cases of meningioma preoperatively evaluated by perfusion MR imaging. A region of interest (ROI) was set inside of the tumor, and perifocal edema of the same size, cerebral blood volume (CBV), and cerebral blood flow (CBF) on perfusion MR and diffusion-weighted (DW) imaging were analyzed. These radiological data were evaluated in comparison with histopathological characteristics. On perfusion MR imaging, the average ratio of CBV against the contralateral side was 6.43 (1.13–20.0) and that of CBF was 7.73 (1.34–11.3). There was no significant relationship with perfusion MR imaging data, tumor volume, or perifocal edema volume. However, the large peritumoral edema group often had a higher CBV and CBF than the non-large peritumoral edema group. The skull base group had a significantly higher CBV and lower signal intensity on DW images than the non-skull base group. Signal intensity on DW images was higher in grade II or III than in grade I. Perfusion MR imaging data revealed that the higher ratio of peritumoral edema against tumor size was associated with higher blood flow and blood volume under intratumoral circulatory conditions, and that skull base meningioma had a higher blood volume than non-skull base meningioma.  相似文献   
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Thirteen patients with gastric metastasis were examined endoscopicallyand their diseases were diagnosed histologically at the NationalCancer Center Hospital from 1962 to 1980. Their endoscopic findings were analyzed. The metastatic lesionwas solitary in 10 of the 13 cases and multiple (9 lesions)in three. Although 12 of the 13 cases showed elevated lesionsendoscopically, ulcerated hemispherical nodules, which correspondto the "bull's-eye sign" of Pomerantz roentgeno-graphically,were observed in only four cases. In the remaining nine casesthe endoscopic findings were submucosal tumor without centraldepression (2 cases), a cancer-like appearance (6 cases) orextragastric compression (1 case). The majority of these metastatic lesions (9 of the 19; 47.3%)were located along the greater curvature of the stomach. Fromthese results, the elevated lesion of the greater curvaturemight suggest a metastatic tumor regardless of the conventionalcriteria (multiplicity or ulcerated hemispherical nodule) whenthe patient has cancer in other organs.  相似文献   
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Neovascularization of the outer membrane plays a critical role in the development and enlargement of chronic subdural hematomas (CSHs) and vascular endothelial growth factor (VEGF) may promote their progression. However, the precise mechanisms remain to be determined. We focused on the signaling pathway upstream of VEGF, transforming growth factor β (TGF-β), and activin receptor-like kinase 1 (ALK-1) to identify the mechanisms underlying the neovascularization of the outer membrane of CSH. Retrospective comparative study was conducted on 15 consecutive patients diagnosed as CSH with burr-hole drainage. Dura and the outer membrane were collected. We immunohistochemically examined the expression of VEGF, integrin-α, TGF-β, and ALK-1 on the outer membrane and dura of CSH and compared our findings with control samples and the signal intensity of hematomas on computed tomography (CT) scans. VEGF and integrin-α expression was markedly up-regulated in both the dura and outer membrane of CSH, the expression of TGF-β and ALK-1 in the dura was slightly increased in the dura and markedly up-regulated in the outer membrane. There was no significant correlation between their expression and CT density. Here we first report the expression of TGF-β and ALK-1 in the outer membrane and dura mater of CSH. We suggest that the TGF-β–ALK-1 pathway and VEGF affect neovascularization and the progression of CSH.  相似文献   
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Primary stent implantation in acute myocardial infarction (AMI) is defined as the intentional (not rescue) implantation of intracoronary stent(s) to the culprit lesion of AMI during emergency catheterization. All available data showed that this strategy has favorable short- and long-term clinical effects compared to primary balloon angioplasty.  相似文献   
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Persistent perfluorinated organic compounds, such as perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) are used in a variety of industrial applications. They are very stable in the environment, distribute widely in the global environment and in wild life, and are detected in human sera.  相似文献   
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Abstract The production rate of leukotriene B4 (LTB4) was measured using peripheral blood mononuclear cells (PBMC) in patients with fulminant hepatitis (FH) or other liver diseases. LTB4 in the culture media of PBMC under stimulation with Ca-ionophore was fractionated by HPLC and measured by radioimmunoassay. The production rate of LTB4 was elevated in 16 of 17 FH patients (3.3 ± 0.2 ng/106 cells for 5 min), while the production was below detectable level in patients with acute or chronic hepatitis and in healthy controls. In FH patients, the highest production rate of LTB4 was observed in the initial period of the disease. Enhanced LTB4 production may indicate the primed state of PBMC — the primed mononuclear cells are regarded as participating in the development of massive liver necrosis and of other organ failures in FH.  相似文献   
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