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Summary We enrolled children with acute lymphoblastic leukemia (ALL) in a Pediatric Oncology Group (POG) pilot study to monitor erythrocyte (RBC) methotrexate (MTX) and folate (F) levels before and during treatment. The mean value for RBCF at diagnosis was 0.86±0.46 nmol/ml RBC in the 214 patients who achieved remission and 1.21±0.74 nmol/ml RBC in the 10 patients who did not (P=0.020). Folate levels tended to increase during remission induction, but they dropped following an intensive consolidation with methotrexate to levels that were sustained throughout chemotherapy treatment. Methotrexate levels reached mean values of approximately 0.15 nmol/ml RBC at the end of an intensive methotrexate consolidation, then fell to levels that were sustained throughout maintenance therapy. There was a weak correlation between improved event-free survival and higher RBCMTX levels after consolidation, but no correlation was found between improved survival and the level of RBCMTX or RBCF during maintenance therapy. A larger study with more complete data is needed to determine whether RBCMTX or RBCF might be useful in predicting event-free survival in patients with ALL.This work was supported in part by grants from the National Cancer Institute and the National Institute of Health (CA-30969, CA-28476, CA29139, CA-159-89, and CA-33587)  相似文献   
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BACKGROUND AND AIMS: Functional gastrointestinal disorders are diagnosed by the presence of a characteristic set of symptoms. Aims of this study were to validate the Rome symptom criteria by factor analysis and to determine whether symptoms cluster in the same way in different cultures. METHODS: One thousand forty-one gastroenterology clinic patients in the US (response rate 53%) and 228 family members accompanying clinic patients in Italy (84%) completed a previously validated symptom questionnaire. Factor analysis identified clusters of symptoms which are highly correlated with each other, and these were compared to the Rome diagnostic criteria. RESULTS: In the US, 13 factors were identified. The irritable bowel factor was composed of three core symptoms corresponding to the Rome II classification system. Two dyspepsia factors were identified which correspond to the ulcer- and motility-like subtypes proposed in the Rome I classification system. All symptoms of constipation formed a single cluster as proposed in the Rome II classification system. Symptom clusters in the US agreed well with symptom clusters identified in Italian subjects. CONCLUSIONS: Empirically derived symptom clusters agree in most respects with the Rome II classification system and support their validity. These symptom clusters are independent of cultural differences in diet and behaviour.  相似文献   
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This paper presents some of the findings from the Smoking in Pregnancy study of attitudes towards smoking among pregnant women, mothers of young children and their partners in East Surrey. As part of the study, respondents completed a General Health Questionnaire to identify mental health difficulties and, if they were smoking at the time of the study, they also completed the Fagerstrom nicotine addiction test. Eleven female respondents had high scores on the General Health Questionnaire, suggesting symptoms of depression, anxiety and/or social dysfunction for these women. There was no evidence that smokers were suffering from greater mental health difficulties than ex-smokers or non-smokers. However, the General Health Questionnaire scores of smokers were positively associated with their level of nicotine dependence. Furthermore, when General Health Questionnaire scores of all respondents were compared with self-reported health status there was a marked discrepancy suggesting under-reporting of symptoms by women.  相似文献   
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