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41.
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Angiomyomatous hamartoma is a rare disease with a predisposition for the inguinal lymph nodes. A 51-year-old male patient visited a local hospital because of a right inguinal mass, measuring 3 x 4 cm in size, which was resected. The resected specimen showed irregularly distributed thick-walled vessels in the hilum, extending into the medulla and focally into the cortex of the node, eventually becoming more dispersed and associated with smooth muscle cells splaying into sclerotic stroma. These findings are compatible with an angiomyomatous hamartoma. Another tumor-like mass appeared shortly after the resection at the same location, but was not an angiomyomatous hamartoma, rather it was composed of edematous stromal tissue with proliferating smooth muscle cells. The stromal component included thick-walled blood vessels and lymphatics. Although it could not be determined whether these associated changes in the surrounding stroma are a cause or an effect of angiomyomatous hamartoma, they indicate the clinical difficulty in determining an appropriate area of resection and may provide clues to the pathogenesis of angiomyomatous hamartoma.  相似文献   
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We investigated whether saber sheath-type tracheomalacia could be treated by the slow release of bone morphogenetic protein (BMP)-2 from a gelatin sponge. A 1 cm gap was made in the middle portion of each of 10 consecutive tracheal cartilage rings in the canine cervix (control group, n = 3), then a gelatin sponge containing 12 microg of BMP-2 solution was implanted in the gap (12 microg group, n = 3). In another group (120 microg + P group, n = 3), the implanted gelatin sponge contained 120 microg of BMP-2 solution, and the gap was covered with periosteum. All of the control dogs developed saber sheath-type tracheomalacia, whereas tracheomalacia was not observed in the 12 microg and 120 microg + P groups. In the 12 microg group, fibrous cartilage was observed at the ends of the cartilage stumps. In the 120 microg + P group, newly formed bone and cartilage were observed to form a bridge between the cartilage stumps. The regeneration of cartilage or bone induced by the slow release of BMP-2 from a gelatin sponge might be useful for treatment of tracheomalacia.  相似文献   
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Dendritic cell-like cells (Mo-DCs) generated from peripheral blood monocytes with interleukin-4 (IL-4) and granulocyte-macrophage colony-stimulating factor (GM-CSF) have been used as tools to treat cancer patients (DC-vaccines). Because Mo-DCs have multiple antigen presentation-related functions, including phagocytosis, migration, cytokine production, and T cell stimulation, establishment of a method for simultaneously evaluating the various functions of Mo-DCs is important. We developed a new in vitro three-dimensional two-layer collagen matrix culture model that consists of a collagen gel containing Mo-DCs as the lower layer and a collagen gel containing necrotic GCTM-1 tumor cells and/or T cells as the upper layer. We used this system to observe simultaneously multiple functions of Mo-DCs by phase-contrast or fluorescence microscopy and to assess IL-12 secretion during more than 2 weeks of culture. We also observed interactions between Mo-DCs and necrotic GCTM-1 or T cells on an individual cell basis by time-lapse videomicroscopy. In addition, we collected Mo-DCs from the collagen gels by collagenase treatment and analyzed the expression of antigen presentation-related molecules such as HLA-DR, CD80, CD83, and CD86 on Mo-DCs. This model may be a useful tool for evaluation of the various functions of Mo-DCs used as DC vaccines and for studies of the complex behaviors of Mo-DCs in vivo.  相似文献   
47.
In hepatitis C virus (HCV)-associated hepatocellular carcinoma (HCC), serum alanine aminotransferase (ALT) is frequently sustained on a high level after hepatectomy, with the formation of recurrent HCC tumors during follow-up periods. We investigated whether or not postoperative serum ALT level affects the interval before recurrence in hepatitis C virus-associated HCC. The subjects studied were 50 hepatectomized HCC patients who were HCV-Ab(+), and underwent a curable surgery in our Hospital from June 1990 to December 1999. We assessed the significance of the postoperative serum ALT level affecting tumor-free survival rates, as compared with other clinicopathological parameters, using univariate and multivariate Cox proportional hazard analysis. Thereafter, tumor-free and overall survival rates after hepatectomy were compared between high and low ALT groups, using Kaplan-Meier plotting and a log-rank test. The factor of ALT levels (a high or low ALT group) was most strongly associated with a tumor-free survival rate. Both tumor-free and overall survival rates were significantly poorer in the high ALT group than in the low ALT group among HCV-associated HCC cases (p<0.05). The results in this study suggest that postoperative hepatitis, which is indicated by sustained high ALT levels, may shorten the interval before recurrence in HCV-associated HCC. We should take care to control postoperative hepatitis to improve the prognoses of HCV-associated HCC cases.  相似文献   
48.
RANEY metals (Ni, Fe, Co), URUSHIBARA metals (Ni, Co) and ULIMANN cu initiate the polymerization of methylmethacrylate. Diamines, diols or organic halides enhance their reactivity. In the presence of CCl4, the polymerization rate (Rp) is proportional to the square root of the amount of both metals and CCl4, and to the first power of the monomer concentration, but Rp becomes constant and independent of the concentration of CCl4 when there is a great excess of CCl4. We concluded that this polymerization follows the free radical mechanism and the participation of a zero-valent metal atom in the initiation reaction including complex formation between metal and CCL4 is suggested.  相似文献   
49.
Cytologic examination of 3H-thymidine-labeled mesothelial cells in the pleural fluid revealed that single and small-sized cells with slight basophilic cytoplasm scarcely stainable by PAS and colloidal iron are in the DNA-synthetic phase and that these are exfoliating cells from the pleural surface. While abnormal labeling in a few arranged and binuclear cells suggesting accelerated or disturbed mesothelial mobilization was frequently found in congestive cardiac failure, liver cirrhosis, and uremia, it never occurred in single and large-sized activated cells possessing rich PAS-positive granules, cells in large clusters or sheet-like arrangements, or multinuclear giant cells. Transmission electron microscopical observation of these labeled cells proved that a smooth cellular surface and scant intracytoplasmic organelles, by which undifferentiated cells are generally characterized, are essential for DNA-synthesizing mesothelial cells. Probably as a result of some pleural irritation, surface lining cells immediately enter the cell cycle and at once revert to an undifferentiated form capable of DNA synthesis, after which they may be released as a single form, and differentiate and transform into mature, activated cells with a bleb-like surface structure or microvilli, and finally may proliferate in the fluid. ACTA PATHOL. JPN. 36: 1279–1296, 1986.  相似文献   
50.
Pulmonary granulomas were induced in BALB/c mice by the intratracheal injection of Sephadex G-50 and latex beads. Very large granulomas developed around Sephadex G-50 beads. Minimal inflammation was produced in mice given latex beads. Aqueous extracts prepared from pulmonary granuloma lesions induced in mice by Sephadex G-50 beads contained high levels of interleukin-1 (IL-1) activity but not interleukin-2 (IL-2) activity. IL-1 activity in the extracts correlated with granuloma size. In a subsequent step, large granulomas were induced by the intratracheal injection of Sepharose 4B beads coupled to fractions of the extracts containing IL-1 activity (ie, granuloma-derived IL-1) prepared from Sephadex G-50-induced granulomatous lungs. In addition, large granulomas were induced by the intratracheal injection of recombinant IL-1-coated Sepharose 4B beads. In contrast, very small granulomas were seen when IL-2-coated or plain Sepharose 4B beads were injected into mice. These results indicate that IL-1 participates in the induction and/or expression of granulomas.  相似文献   
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