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81.
Cytotoxic treatment of adrenocortical carcinoma   总被引:4,自引:1,他引:3  
Adrenocortical carcinoma (ACC) is a rare, aggressive tumor that is often detected in an advanced stage. Medical treatment with the adrenotoxic drug mitotane has been used for decades, but critical prospective trials on its role in residual disease or as an adjuvant agent after surgical resection are still lacking. The concept of a critical threshold plasma level of the drug must be confirmed in controlled studies. Because individual responsiveness cannot be predicted, the use mitotane is still advised for nonresectable disease. In case of cortisol or other steroid overproduction, several drugs (e.g., ketoconazole or aminoglutethimide) may be used. Chemotherapy with single agents (e.g., doxorubicin or cisplatin) have been disappointing, with low response rates (< 30%) and a short response duration. Part of this refractoriness may be explained by the fact that ACC tumors express the multidrug-resistance gene MDR-1. Chemotherapy with multiple agents has been tested in smaller series and has resulted in significant side effects. The best results were achieved by the combination of etoposide, doxorubicin, and cisplatin associated with mitotane, achieving a response rate of 54%, including individual complete responses. To be able to make progress in treating advanced ACC disease, adjuvant multicenter trials must be encouraged. When mitotane-based therapies are used, monitored drug levels are mandatory.  相似文献   
82.
There are conflicting reports in the literature as to whether palmitoylethanolamide affects the function of mast cell-related cell lines in vitro, in contrast to the well-documented effects of this compound upon mast cell function in vivo. In the present study, we have reinvestigated the effects of palmitoylethanolamide upon antigen-induced release of [3H]serotonin and beta-hexosaminidase from rat basophilic leukemia RBL-2H3 cells and compared these effects with those of 2-arachidonoylglycerol, anandamide and R1-methanandamide. RBL-2H3 cells were sensitized with a monoclonal anti-DNP IgE, after which they were stimulated with antigen (DNP-HSA). Palmitoylethanolamide produced a small, but significant reduction in antigen-stimulated [3H]serotonin release at high concentrations, whereas anandamide was without effect. In contrast, 2-arachidonoylglycerol and methanandamide increased the antigen-stimulated release of both [3H]serotonin and beta-hexosaminidase. It is concluded that in RBL-2H3 cells, these cannabimimetic fatty acid derivatives do not have potent stabilizing effects upon antigen-induced degranulation.  相似文献   
83.
Masked monosomy 7, i.e. detected by FISH but not by conventional cytogenetics, has been reported in varying frequency in MDS. To establish the prevalence and possible clinical significance of the aberration, we studied the 123 previously karyotyped MDS patients using FISH and a DNA probe specific for chromosome 7. Metaphase cytogenetics revealed ten patients (8%) with monosomy 7 (6 RAEB and 4 RAEB-t). FISH confirmed this result and detected four more cases (4%) with masked monosomy 7 (3 RA and 1 RARS). Thus, masked monosomy 7 is less common than has been suggested, and does not seem to carry the same prognostic weight as monosomy 7 diagnosed by metaphase cytogenetics.  相似文献   
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Seventeen patients with probable Alzheimer's disease (AD), 7 patients with frontal lobe dementia (FLD) and 19 control subjects (NOR) were examined by (99m)Tc-d,l- hexamethylpropylene amine oxime ((99m)Tc-HMPAO) SPECT. Images were standardised in the same 3D space and averaged within each group. After normalisation, the three sets of images were analysed in all cerebral lobes, hippocampus, thalamus and basal ganglia. In AD, the (99m)Tc-HMPAO uptake values were significantly reduced, as compared to NOR, in the parietal, temporal and insular lobes. In patients with FLD, the uptake was altered in all lobes with the exception of the parietal lobe. The uptake in the nucleus caudatus decreased significantly in both AD and FLD as compared to NOR. The uptake in the anterior cingulate cortex was significantly reduced in FLD. Subtraction images highlighted all significantly decreased areas. In conclusion, standardising SPECT in a common space and subtracting data from a control group improves the visual interpretation of images. In this study, the typical temporo-parietal and fronto-parietal (99m)Tc-HMPAO uptake reductions were found in AD and FLD, respectively. The uptake in the nucleus caudatus was found to decrease significantly in AD and FLD and the one in the anterior cingulate cortex was reduced in FLD.  相似文献   
86.
OBJECTIVE: To correlate cervical and amniotic fluid cytokines and macrophage-related chemokines to the development of histological chorioamnionitis (HCA) in patients with preterm labor (PTL) and preterm prelabor rupture of the membranes (PPROM). STUDY DESIGN: Cervical and amniotic fluid interleukin (IL)-6, IL-8, IL-18, monocyte chemotactic protein (MCP)-1, MCP-2, and MCP-3 from pregnant women (at 相似文献   
87.
OBJECTIVES: To study and describe how a group of senior researchers and a group of postgraduate students perceived the so-called "grey zone" between normal scientific practice and obvious misconduct. DESIGN: A questionnaire concerning various practices including dishonesty and obvious misconduct. The answers were obtained by means of a visual analogue scale (VAS). The central (two quarters) of the VAS were designated as a grey zone. SETTING: A Swedish medical faculty. SURVEY SAMPLE: 30 senior researchers and 30 postgraduate students. RESULTS: Twenty of the senior researchers and 25 of the postgraduate students answered the questionnaire. In five cases out of 14 the senior researchers' median was found to be clearly within the interval of the grey zone, compared with three cases for the postgraduate students. Three examples of experienced misconduct were provided. Compared with postgraduate students, established researchers do not call for more research ethical guidelines and restrictions. CONCLUSION: Although the results indicate that consensus exists regarding certain obvious types of misconduct the response pattern also indicates that there is no general consensus on several procedures.  相似文献   
88.
BACKGROUND: To evaluate the efficacy and toxicity of cisplatin/etoposide continuous infusion chemotherapy for cancer of unknown primary site in Taiwan, a region with a high prevalence of endemic viral infections. METHOD: Between April 1994 and February 1996, 20 patients with a diagnosis of CUPS were treated, including 15 males and five females, of average age 63.3 years (range 41-83 years). Continuous intravenous infusion of etoposide 80 mg/m2 and cisplatin 25 mg/m2 was given for 3 days every 3 weeks. Pretreatment tumor marker and viral serology studies were performed for baseline evaluation. Nearly two-thirds of the patients had poorly differentiated carcinoma. The average number of metastatic sites was 2.65 (range 1-4), with liver and lymph node involvement predominating. RESULTS: The overall response rate was 25% (95% CI 17.7-32.3%); 30.7% for poorly differentiated cancers and 25% for well differentiated cancers. Median survival was 4 months (range 1-12 months), 4.8 months for patients attaining partial response. Toxicity was moderate, grade 3 and 4 neutropenia occurred in 55% and grade 3 and 4 thrombocytopenia in 40%; other toxicities were mild. CA125 and CA199 were elevated in more than 50% of patients. Viral serology studies were not significantly different from those of the indigenous population. CONCLUSION: Etoposide and cisplatin combination chemotherapy has modest activity in patients with extensive CUPS and, at the schedule and dosage given, it is associated with moderate toxicity.   相似文献   
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