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51.
We examined whether macrophage infiltration is associated with angiogenesis in cutaneous melanoma. The numbers of macrophages and microvessels increased significantly with increasing depth of tumor and with tumor angiogenesis. Macrophage infiltration thus appeared to provide a useful diagnostic marker for the progression of cutaneous melanoma. We further examined whether human melanoma cells produce angiogenic factors in response to macrophage-derived cytokines, tumor necrosis factor alpha (TNFalpha) and interleukin-1 alpha (IL-1alpha). Treatment of melanoma cells with TNFalpha and IL-1alpha in vitro enhanced the production of interleukin-8 (IL-8) and vascular endothelial growth factor (VEGF), and of basic fibroblast growth factor (bFGF) to a lesser degree, in human melanoma cells. Lipopolysaccharide (LPS)-activated human monocytes enhanced production of IL-8, VEGF, TNF alpha, as well as IL-1alpha, but not bFGF. Co-culture of human monocytes and human melanoma cells was also found to significantly enhance production of IL-8 and VEGF in the absence and presence of LPS, compared with either monocytes or melanoma cells alone. The production of IL-8 and VEGF from co-cultured melanoma cells and LPS-activated monocytes was blocked when anti-TNF-alpha antibody or anti-IL-1alpha antibody was co-administrated. This is direct evidence that production of the potent angiogenic factors IL-8 and VEGF from melanoma cells is up-regulated through TNFalpha and/or IL-1alpha secreted by activated monocytes/macrophages, influencing both tumor growth and angiogenesis in melanomas.  相似文献   
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A follow-up survey of survivals (Oct. 1 '80 to May 1, '84) in a randomized controlled study (Aug. '79 to Sept. 30' 80) of lentinan in combination administration with chemotherapeutic agents such as 5FU + mitomycin C or tegafur on patients with advanced or recurrent gastrointestinal cancer has shown that lentinan has been effective in such cases with regard to the following facts: 1) A life span prolongation effect at the end-point has been observed with statistical significance in lentinan treated patients as was found in the phase III study. 2) Using the life table analysis method, a higher rate of survival has been observed in the lentinan treated group, especially in combination with tegafur for gastric cancer, clearly showing such high survival rates as 12.97% (P less than 0.05) at two years after, and 9.51% (P less than 0.05) and 3.81%, at three and four years after respectively, and for colorectal cancer, 9.10% and 4.55% at two years and three years after, respectively.  相似文献   
54.
Single photon emission computed tomography (SPECT) is useful for detecting brain tumors. In this study, we evaluated the utility of simultaneous dual SPECT with 201Tl-Chloride (Tl) and 99mTc-MIBI (MIBI) for diagnosis of brain tumors. We evaluated 20 cases, including 2 glioblastomas, 7 anaplastic astrocytomas, 2 oligodendrogliomas, 2 anaplastic ependymomas, 2 medulloblastomas, 2 meningiomas, 1 malignant meningioma, 1 pituitary adenoma, and 1 craniopharyngioma. We analyzed the uptake ratio (T/N ratio) of tracers in both Tl and MIBI at max counts/pixels ratio in the region of interest. The T/N ratios in early and delayed images were described as early ratios (ER) and delay ratios (DR), respectively. The retention index (RI) was calculated as the DR/ER ratio. Significant correlations were found between ER and DR for both Tl (DR = 0.797 * ER + 0.359, r = 0.871), and MIBI (DR = 0.961 * ER - 0.191, r = 0.784). Next, we analyzed the correlations between Tl and MIBI SPECT, for ER, DR, and RI. ER values for the two were strongly correlated (r = 0.791), DR values were weakly correlated (r = 0.556), and RI exhibited no correlation between them (r = 0.328). There were no correlations between tumor volume and T/N ratio for the two (ER-Tl; r = 0.0095, DR-TI; r = 0.0050, ER-MIBI; r = 0.036, DR-MIBI; r = 0.254). Lastly no correlation was found between RI-Tl and RI-MIBI (r = 0.328). We discuss the difference in the mechanism of accumulation of two tracers and the significance of simultaneous dual SPECT using them for the differential diagnosis of pituitary tumors, regrowth of oligodendrogliomas, and multidrug resistance of chemotherapy. Dual SPECT with Tl and MIBI appears to be useful for the diagnosis of brain tumor.  相似文献   
55.
BACKGROUND AND PURPOSE: Membrane constituents may play a key role in the magnetization transfer (MT) effect. In lamprey spinal cord, axonal diameters range from <1 microm in the dorsal region to 20-40 microm in the ventral region. There is a corresponding range of axonal, and hence cell membrane, density. These characteristics permit determination of the effect of cell membrane density on MT. The purpose of this study was to characterize regional MT effects in lamprey spinal cord. METHODS: Excised spinal cords from eight sea lampreys were measured with a 9.4-T MR imaging system. MT saturation was applied for spin-echo sequences. The MT ratio (MTR) was calculated in each location (dorsal, lateral, and ventral columns). Spinal cords from five other lampreys were prepared with an antibody to lamprey glial keratin (LCM 29). The percentage of area staining with LCM29 was calculated for each location. RESULTS: Mean MTR (+/- SD) for the dorsal, lateral, and ventral columns were 62.4 +/- 4.2, 59.2 +/- 2.7, and 56.9 +/- 3.0, respectively; all differences were significant (P < .05). Mean LCM29-positive areas for the dorsal, lateral, and ventral columns were 85.1%, 69.7%, and 50.9%, respectively. MTR and percentage LCM29-positive area were significantly correlated (r(2) = 0.98). CONCLUSION: Regional differences in MT effect exist in the lamprey spinal cord. MTR is well correlated with percentage LCM29-positive area. These results support the hypothesis that membrane constituents are at least partly responsible for regional variations in MT effect.  相似文献   
56.
Encapsulated fat necrosis is a degenerative process involving various mature adipose tissues. We report on a case of abdominal encapsulated fat necrosis which mimicked abdominal liposarcoma, and we discuss its imaging findings on computed tomography (CT).  相似文献   
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58.
Gastrointestinal stromal tumor of the retroperitoneum: CT and MR findings   总被引:5,自引:1,他引:4  
Gastrointestinal stromal tumor (GIST) is a non-epithelial neoplasm arising from the wall of the gastrointestinal (GI) tract. Although the majority of GISTs are located in the GI tract, some GISTs occur in the omentum, mesentery and retroperitoneum. GIST arising in the retroperitoneum is extremely rare, and its radiological findings have not been well described. We report a case of primary retroperitoneal GIST and discuss its imaging findings.  相似文献   
59.
A 14-year-old girl with rapidly progressive glomerulonephritis was transferred to our hospital because of acute renal failure. A diagnosis of Wegener granulomatosis was made according to the symptom triad of a renal biopsy demonstrating crescentic glomerulonephritis, severe sinusitis, and serological findings of raised proteinase 3 anti-neutrophil cytoplasmic antibody level. In spite of combination therapy with methylprednisolone, cyclophosphamide, and plasma exchange, her renal function gradually deteriorated. Thereafter, she suffered a severe headache and generalized seizures. Brain computed tomography (CT) scan revealed bilateral low-density areas in the parieto-occipital lobes. Magnetic resonance imaging (MRI) disclosed a high-intensity area on T2-weighted images and a low-signal intensity area on T1-weighted images in the same lesion. Follow-up brain CT scan 3 weeks and MRI 2 months after the first studies showed complete resolution of the abnormal lesions, which indicated reversible posterior leukoencephalopathy syndrome. In addition to renal failure, hypertension, and cyclophoshamide, the primary disease may have played a role in the development of this uncommon syndrome in our patient.  相似文献   
60.
Bacterial control in poultry processing plants is very important, but the swab method for estimating bacterial contamination is somewhat troublesome in routine work. We compared the Desoxycholate Agar Nissui Food Stamp (DA-NFS) based on the agar contact method with the swab method to estimate coliform organisms from various equipments in four poultry processing plants after cleaning. Overall 104 surfaces for coliform organisms were evaluated. The results from 98 (94.2%) surfaces for coliform organisms were equivalent by the DA-NFS and swab methods and there were no significant differences between two methods (P > 0.05). The correlation coefficient between the DA-NFS and swab methods was 0.91. We conclude that the DA-NFS could be useful for routine coliform organisms examination in poultry processing plants after cleaning in Japan.  相似文献   
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