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91.
92.
An 18-year-old male was admitted to our Emergency Department with a traumatic abdominal wall hernia (TAWH) of the left lower quadrant (LLQ) after suffering hypogastric blunt injury and urogenital lacerations in a motorcycle accident. Upright chest X-ray showed a small amount of right infradiaphragmatic free air, and a computed tomographic (CT) scan demonstrated an abdominal wall hernia. At surgery, no impairment was found in the digestive tract, and an abdominal herniorrhaphy was performed. It is suggested that the free air had passed through a connection between the scrotal laceration and the contralateral abdominal defect via the subcutaneous space and was palpated as emphysema. This is a new type of TAWH, which suggests that blunt abdominal trauma may result in negative pressure in the subcutaneous and peritoneal cavity, and this could reflect the pathophysiology of TAWH.  相似文献   
93.
To improve low-pitched voices in cases with polypoid vocal cords, YAG laser irradiation combined with a mucosal suturing technique was attempted in 9 female cases with severe polypoid changes in their vocal cords. A YAG laser beam (5 to 10 W) was used to irradiate the upper surface of the polypoid vocal cord. The polypoid content of the cord was gradually coagulated, and the free edge of the cord appeared to slide up toward the burned area. The polypoid content was then removed and squeezed through an open wound made in the burned area using a conventional method. Bleeding was successfully controlled using the laser. After the excessive mucosal margin was trimmed and the contour of the vocal cord was adjusted, the wound was closed by 7-0 monofilament absorbable suture. Suturing was relatively easy because the mucosal edge was also coagulated. Postoperative evaluations of voice quality revealed an improvement in the GRBAS scale of voice quality as well as an elevation in voice pitch and an upwards shift in the voice range in all cases.  相似文献   
94.
PURPOSE: The E-cadherin-mediated cell adhesion system is frequently inactivated by multiple mechanisms and is involved in tumor progression in many types of cancer. Recently, we reported the cloning and characterization of dysadherin and showed that it downregulated E-cadherin and promoted metastasis. The aim of this study was to investigate the clinical significance of dysadherin expression and the relationship between dysadherin expression and E-cadherin expression in pancreatic ductal adenocarcinoma. PATIENTS AND METHODS: We examined dysadherin and E-cadherin expression in 125 surgically resected pancreatic ductal adenocarcinoma patients using immunohistochemistry. RESULTS: Dysadherin was expressed at the cell membrane of cancer cells, but not in nontumor duct and acinar cells. Its expression was stronger in infiltrative and poorly differentiated nests compared with well-differentiated nests. Although the correlation between the expression of dysadherin and E-cadherin was not significant, a group of patients showed reduced E-cadherin expression with dysadherin overexpression. Increased dysadherin expression was significantly correlated with distant metastasis (P =.047), high tumor grade (P =.006), positive tumor margins (P =.024), and infiltrative type of growth pattern (P =.014). A survival advantage was observed in patients with 0% to 20% dysadherin-positive cells compared with patients with 51% to 100% dysadherin-positive cells, independent of tumor-node-metastasis classification, and World Health Organization tumor grade (P =.019). A combination of increased dysadherin expression and reduced E-cadherin expression (< 90%) further worsened the prognosis. CONCLUSION: In pancreatic ductal adenocarcinoma, dysadherin expression seems to reflect tumor aggressiveness and to be a positive marker of poor prognosis when considered both alone and in combination with downregulation of E-cadherin.  相似文献   
95.
The mechanism of macrolide therapy in chronic sinusitis patients is unclear. The authors studied the effect of macrolides on interleukin (IL)-8 secretion from cultured human nasal epithelial cells. Epithelial cells harvested from the nasal polyps of patients with chronic sinusitis were primary-cultured, and secreted IL-8 in culture media was measured by enzyme immunoassay. The cells secreted considerable amounts of IL-8 constitutively and in response to lipopolysaccharide. The secretion was significantly inhibited by 10?5 M of erythromycin, clarithromycin, roxithromycin, and josamycin. 10?6 M erythromycin still showed the inhibitory effect, whereas the same concentration of josamycin did not. These results indicate that macrolide antibiotics may act as an immunomodulator to reduce IL-8 in inflammatory sites and, at least partially, account for the clinically discrepant effects between 14- and 16-membered ring macrolides in long-term low-dose therapy for chronic sinusitis.  相似文献   
96.
97.
Urinary bladder cancers occurring after prolonged cyclophosphamide therapy are being increasingly reported. Cyclophosphamide-induced cancer in the upper urinary tract is not, however, generally recognized. We report a case of asynchronous development of transitional cell carcinoma in the bladder and renal pelvis, after prolonged cyclophosphamide therapy for non-Hodgkin's lymphoma. To date, at least 8 cyclophosphamide-related cancers have been reported in the upper tract. These cases are reviewed briefly.  相似文献   
98.
Induction of antitumor immunity to T-9 rat glioma by intracellular hyperthermia using functional magnetic particles was investigated. Magnetite cationic liposomes (MCLs), which have a positive surface charge, were used as heating mediators for intracellular hyperthermia. Solid T-9 glioma tissues were formed subcutaneously on both femurs of female F344 rats, and MCLs were injected via a needle only into the left solid tumors (treatment side). The rats were then divided into two groups, which received no irradiation, or irradiation for 30 min given three times at 24-h intervals with an alternating magnetic field (118 kHz, 384 Oe). On the treatment side, the tumor tissue disappeared completely in many rats exposed to the magnetic field. The tumor tissue on the opposite side also disappeared completely, even though MCLs were not injected into the right solid tumors. To examine whether a long-lasting and tumor-specific immunity could be generated, the rats that had been cured by the hyperthermia treatment were rechallenged with T-9 cells 3 months later. After a period of transient growth, all tumors disappeared. Furthermore, immuno-cytochemical assay revealed that the immune response induced by the hyperthermia treatment was mediated by both CD8+ and CD4+ T cells and accompanied by a marked augmentation of tumor-selective cytotoxic T lymphocyte activity. These results suggest that our magnetic particles are potentially effective tools for hyperthermic treatment of solid tumors, because in addition to killing of the tumor cells by heat, a host immune response is induced.  相似文献   
99.
To search for the signaling events in colorectal carcinoma relevant to its tumorigenesis, we investigated the activity of mitogen-activated protein kinase (MAPK) in human colorectal carcinoma tissues and paired normal tissues. Of 64 cases examined, approximately 75% (48 cases) showed tumor-specific activation of MAPK by in situ kinase renaturation assay, as well as in vitro kinase assay with immunoprecipitated MAPK. In addition, tumor-specific activation of MAPK was associated with the activation of MAPK kinase in the cases we examined. However, no clear correlation of MAPK activation with lymph node involvement, metastatic rate, stage, histological classification, age or sex was observed. These results suggest that the MAPK pathway is involved in colorectal tumor development, but its activation alone is not sufficient for malignant conversion. In contrast to colorectal carcinoma, gastric carcinoma tissues showed a lower rate of MAPK activation, suggesting that the signaling pathway activated in colorectal carcinoma tissues may differ in part from that of gastric carcinoma.  相似文献   
100.
Cells of the human tumor cell line RMG-1, derived from a clear-cell adenocarcinoma of the ovary, were injected intraperitoneally into nude mice, and the cells obtained from the tumor nodules in the mesenterium were found to form a larger number of, and larger-sized, tumor nodules than the original RMG-1 cells. The RMG-1-h cells, transferred into culture from the tumor nodules after a 4th in vivo passage, showed a dissemination potential as high as that of cells disseminating directly from the tissues, and exceedingly higher than that of RMG-1 cells. To assess the molecular bases of the different biological properties of RMG-1 and RMG-1-h cells, we compared the content and expression of various carbohydrate antigens in both cells. The chromosomal profile of RMG-1-h cells revealed their human origin and was identical to that of the original RMG-1 cells. In contrast to the broad histogram for the Lex-bearing cells among RMG-1 cells in flow cytometry, the weakly and moderately positive cells toward anti-Lex antibody were found to be eliminated from the histogram for the RMG-1-h cells, resulting in the enrichment of cells strongly expressing Lex, which may account for the high dissemination potential. In addition, the adhesion of RMG-1 cells to mesothelial cells was found to be significantly inhibited by pretreatment of the cells with anti-Lex antibody, indicating Lex-mediated cell-to-cell interaction between ovarian cancer cells and mesothelial cells. By TLC-immunostaining, two Lex-glycolipids, III3Fucα-nLc4Cer and V3Fucα-nLc6Cer were detected in both RMG-1 and RMG-1-h cells, and their total concentrations were not significantly different from each other. However, the hydrophobic moieties of Lex-glycolipids in RMG-1-h cells were different from those in RMG-1 cells, suggesting that a difference in the structure of the hydrophobic moieties of Lex is partly involved in the enhanced reactivity of RMG-1-h cells toward anti-Lex antibody. Thus, the high dissemination potential of ovarian cancer cells was shown to be mediated by the Lex-determinant and the Lex-bearing cells are enriched by repeated in vivo passage of the cells into nude mice.  相似文献   
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