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121.
Background The purpose of this study was to assess the accuracy of contrast-enhanced magnetic resonance imaging (dynamic MR imaging) in the evaluation of preinvasive and early invasive cancer of the cervix. Methods Twenty-nine women with untreated squamous cell carcinoma of the cervix with either no stromal invasion or early stromal invasion underwent pretreatment MR imaging and dynamic MR imaging within 4 weeks of surgical evaluation. The images were evaluated for tumor detection and compared with results of histologic examination of the surgical specimens. Results The lesions in 17 cases with histologically proven stromal invasion of 4 mm or greater were detected with dynamic MR imaging, whereas lesions in only 8 of these cases were detected with T2 imaging. In 9 cases with stromal invasion between 4.0 mm and 5.0 mm, lesions were represented as early phase focal enhancement on dynamic MR images, but not detected on T2-weighted images. In the 12 cases with less than 4 mm stromal invasion, no lesions were visualized on either T2-weighted images or dynamic MR images, except in 1 case of glandular involvement without stromal invasion that appeared as enhancement on early-phase dynamic MR imaging. Conclusion Dynamic MR imaging detected more lesions of early stromal invasion in pretreatment imaging for cervical cancer than nonenhanced MR imaging.  相似文献   
122.
Paclitaxel and irinotecan are important new anticancer agents. The combination of these two agents has been considered for use against a variety of advanced solid tumors. Since the schedule-dependent effects of this combination may be crucial to its use, we studied the interaction of paclitaxel and SN-38 (the active metabolite of irinotecan) in various schedules in four human cancer cell lines in culture. Cell growth inhibition after 5 days was determined using an MTT assay. The effects of drug combinations at the IC80 level were analyzed by the isobologram method. Simultaneous exposure to paclitaxel and SN-38 for 24 h produced antagonistic (subadditive and protective) effects in the human lung cancer cell line A549, the breast cancer cell line MCF7, and the colon cancer cell line WiDr, and produced additive effects in the ovarian cancer cell line PA1. Sequential exposure to paclitaxel for 24 h followed by SN-38 for 24 h, and the reverse sequence, produced additive effects in all four cell lines. These findings suggest that sequential administration, not simultaneous administration, may be the appropriate schedule for the therapeutic combination of paclitaxel and irinotecan. Continued preclinical and clinical studies should provide further insights and assist in determining the optimal schedule for this combination in clinical use. Received: 25 February 1997 / Accepted: 6 November 1997  相似文献   
123.
To identify virological parameters (serostatus of hepatitis B surface antigen [HBsAg] and antibodies to hepatitis C virus [anti-HCV], HCV genotypes and HCV-RNA titer) and other clinico-biological and lifestyle variables that may influence or predict the development of hepatocellular carcinoma (HCC) in cirrhosis, we followed 100 cirrhotic patients without HCC, who visited Kyushu University Hospital between 1985 and 1987, until the end of 1995 (follow-up rate: 98%; average follow-up period: 5.3 years). After elimination of 4 patients who developed HCC or were censored within the initial 6 months, 37 (39%) out of 96 patients developed HCC during follow-up. As compared with HBsAg(+) patients, anti-HCV(+) HBsAg(-) patients demonstrated significantly elevated HCC risk (adjusted hazard ratio [HR] = 5.85, 95% confidence interval [CI] 1.65-20.67). Genotype 1 HCV infection was not associated with increased risk compared with genotype 2 (HR = 0.64, 95% CI 0.21-1.99). For genotype 1 HCV infection, patients with HCV-RNA levels < 1 Meq/ml tended to present lower risk than patients with > or = 1 Meq/ml (P = 0.03). Male sex, advanced Child's class, lower serum albumin, and higher serum aminotransferase and alpha-fetoprotein were also found to be strong predictors. Overall, drinking and smoking habits were not associated with significantly elevated risk. Among virological parameters, anti-HCV positivity and, possibly high HCV-RNA titer, were predictive of HCC occurrence in cirrhosis in our clinical setting.  相似文献   
124.
Objective: To evaluate the effect of prednisolone plus low-dose aspirin (PSL/LDA) in women with autoimmune conditions who were enrolled in an IVF-ET program.

Design: A retrospective clinical study.

Setting: In vitro fertilization unit, Niigata University Hospital, Niigata, Japan.

Patient(s): Three hundred seven women who underwent IVF-ET between January 1996 and December 1997.

Intervention(s): Prednisolone (10 mg/d) and aspirin (81 mg/d) were administered to the women with autoantibodies who chose to participate.

Main Outcome Measure(s): Pregnancy and implantation rates with IVF-ET.

Result(s): Women undergoing IVF who had positive antinuclear antibodies, with or without antiphospholipid antibodies, had significantly lower pregnancy and implantation rates than did women without autoantibodies (14.8% versus 21.7% and 6.8% versus 10.4%, respectively). The administration of PSL/LDA to women with antinuclear antibodies significantly improved the outcome of IVF-ET (40.6% pregnancy rate and 20.3% implantation rate).

Conclusion(s): A high proportion of women who are undergoing IVF-ET have autoantibodies, which are associated with poor IVF outcomes. The administration of PSL/LDA to these women may improve their implantation rate.  相似文献   

125.
AIM: Although thallium-201 (201Tl) has been used for the diagnosis of lung cancer, its detectability of small pulmonary nodules is not known. The aim of this study was to evaluate the ability of 201Tl SPECT for the differential diagnosis for the pulmonary nodules 20 mm in diameter or smaller. METHODS: 201Tl SPECT was performed in 31 patients suspected of having primary lung cancer. The final diagnosis was established by histology, and tumor size was 10 to 20 mm in diameter. Twenty of 31 patients had malignant tumors, including squamous cell lung cancer (n = 5), adenocarcinoma (n = 14) and small cell lung cancer (n = 1), but in none of them was there mediastinal lymphnode involvement. RESULTS: Ten of 20 malignant tumors and 1 of 11 benign lesions demonstrated significant 201Tl uptake, so that the positive predictive value, negative predictive value, sensitivity and specificity for the diagnosis of lung cancer were 90.9% (10/11), 50.0% (10/20), 50.0% (10/20) and 90.9% (10/11), respectively. CONCLUSION: These data suggest that sensitivity for detecting lung cancer 20 mm or less in diameter may be insufficient, but even in patients with small pulmonary nodules, a positive 201Tl result is highly predictive of lung cancer.  相似文献   
126.
Nutrients such as glucose stimulate insulin release from pancreatic beta-cells through both ATP-sensitive K+ channel-independent and -dependent mechanisms, which are most likely interrelated. Although little is known of the molecular basis of ATP-sensitive K+ channel-independent insulinotropic nutrient actions, mediation by cytosolic long-chain acyl-CoA has been implicated. Because protein acylation might be a sequel of cytosolic long-chain acyl-CoA accumulation, we examined if this reaction is engaged in nutrient stimulation of insulin release, using cerulenin, an inhibitor of protein acylation. In isolated rat pancreatic islets, cerulenin inhibited the glucose augmentation of Ca2+-stimulated insulin release evoked by a depolarizing concentration of K+ in the presence of diazoxide and Ca2+-independent insulin release triggered by a combination of forskolin and phorbol ester under stringent Ca2+-free conditions. Cerulenin inhibition of glucose effects was concentration dependent, with a 50% inhibitory concentration (IC50) of 5 microg/ml and complete inhibition at 100 microg/ml. Cerulenin also inhibited augmentation of insulin release by alpha-ketoisocaproate, a mitochondrial fuel. Furthermore, cerulenin abolished augmentation of both Ca2+-stimulated and Ca2+-independent insulin release by 10 micromol/l palmitate, which causes palmitoylation of cellular proteins. In contrast, cerulenin did not attenuate insulin release elicited by nonnutrient secretagogues, such as a depolarizing concentration of K+, activators of protein kinases A and C, and mastoparan. Glucose oxidation, ATP content in islets, and palmitate oxidation were not affected by cerulenin. In conclusion, cerulenin inhibits nutrient augmentation of insulin release with a high selectivity. The finding is consistent with a prominent role of protein acylation in the process of beta-cell nutrient sensing.  相似文献   
127.
Chemotherapyremainsoneofthemosteffectivetreatmentsfordisseminatedneoplasia[1 ] .However,theef ficacyofmanychemotherapeuticagentsislimitedbytheirtoxicitytonormaltissues,resultinginanarrowtherapeuticindex.Myelosuppressionisthemostfrequentacutedose limitingsideeffectresponsiblefordelaysindrugadminis trationordoseattenuationwithdecreasedantitumorre sponse[2 4] .Particularly,thrombocytopeniaremainsasig nificantcauseofmorbidityincancerpatientsundergoingallogenicorautologousbonemarrow/bloodstemcellt…  相似文献   
128.
Calpain inhibitor inhibits secretory granule maturation and secretion of GH   总被引:2,自引:0,他引:2  
Clathrin- and AP-1-coated buds are present on immature secretory granules of endocrine cells that mature into clathrin-uncoated granules. The mechanism of clathrin and adaptor protein uncoating has remained obscure. Benzyloxycarbonyl-L-leucyl-L-leucinal (ZLLal), a calpain inhibitor, reduced growth hormone (GH) secretion with intracellular accumulation, in a GH-secreting rat pituitary tumor cell. Pulse and chase demonstrated that ZLLal retarded the turnover of clathrin (Clt.H) and adaptins. ZLLal-treatment co-immunoprecipitated the increased amounts of GH with Clt.H and adaptins compared to control cells, suggesting the intracellular accumulation of immature secretory granules. Clt.H and adaptins were limited-proteolyzed by m-calpain in vitro, indicating that calpain may be involved partly in the maturation of secretory granules in endocrine cells via the process of clathrin uncoating.  相似文献   
129.
The hepatotoxic effects of alcohol have been described in detail, but factors responsible for its hepatotoxicity have only partially characterized. It now appears that Kupffer cell derived TNF-alpha participates in several aspects of alcoholic liver injury. On the other hand, protease inhibitors have been used successfully for treatment of intractable diseases in which TNF-alpha is involved in the pathogenesis, including ulcerative colitis and Crohn's disease. Here, we will review new evidence for the proposal that serine protease inhibitors prevents alcoholic liver injury via mechanisms dependent on Kupffer cell derived TNF-alpha.  相似文献   
130.
Cancer immunotherapy by fusion of antigen-presenting cells and tumor cells has been shown to induce potent antitumor immunity. In this study, we characterized syngeneic and allogeneic, murine macrophage/dendritic cell (DC)-cancer fusion cells for the antitumor effects. The results showed the superiority of allogeneic cells as fusion partners in both types of antigen-presenting cells in an in vivo immunotherapy model. A potent induction of tumor-specific CTLs was observed in these immunized conditions. In addition, the immunization with DC-cancer fusion cells was better than that with macrophage-cancer fusion cells. Both syngeneic and allogeneic DC-cancer fusion cells induced higher levels of IFN-gamma production than macrophage-cancer fusion cells. Interestingly, allogeneic DC-cancer fusion cells were superior in that they efficiently induced Th1-type cytokines but not the Th2-type cytokines interleukin (IL)-10 and IL-4, whereas syngeneic DC-cancer fusion cells were powerful inducers of both Th1 and Th2 cytokines. These results suggest that allogeneic DCs are suitable as fusion cells in cancer immunotherapy. To further enhance the antitumor immunity in the clinical setting, we prepared DCs fused with IL-12 gene-transferred cancer cells and thus generated IL-12-secreting DC-cancer fusion cells. Immunization with these gene-modified DC-cancer fusion cells was able to elicit a markedly enhanced antitumor effect in the in vivo therapeutic model. This novel IL-12-producing fusion cell vaccine might be one promising intervention for future cancer immunotherapy.  相似文献   
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