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Chronic Azithromycin (AZM) is a common treatment for lung infection. Among adults at risk of cardiac events, AZM use has been associated with cardiovascular harm. We assessed cardiovascular safety of AZM among children with CF, as a secondary analysis of a placebo-controlled, clinical trial, in which study drug was taken thrice-weekly for a planned 18 months. Safety assessments using electrocardiogram (ECG) occurred at study enrollment, and then after 3 weeks and 18 months of participation. Among 221 study participants with a median of 18 months follow-up, increased corrected QT interval (QTc) of ≥30 msec was rare, at 3.4 occurrences per 100 person-years; and incidence of QTc prolongation was no higher in the AZM arm than the placebo arm (1.8 versus 5.4 per 100 person-years). No persons experienced QTc intervals above 500 msec. Long-term chronic AZM use was not associated with increased QT prolongation.  相似文献   
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PURPOSE: To evaluate the acceptability and feasibility of using the new transdermal contraceptive patch in adolescents. METHODS: A 3-month longitudinal trial using the Ortho Evra transdermal contraceptive patch in 50 adolescent girls. All healthy girls aged 15-18 years were invited to participate from two San Francisco Bay Area teen clinics. Participants were followed after 1 month and 3 months of treatment. Data were collected on patch detachments, perceived advantages and disadvantages, side effects, and compliance. Data were analyzed using Student's t-test (SPSS). RESULTS: Forty participants (80%) completed 1 month of treatment and 31 (62%) completed all 3 months of the study. There were no pregnancies during treatment. At the 3-month follow-up, 87.1% of participants reported perfect compliance. Ease of use, the fact that it does not require daily attention, and the ease of concealment were among the main reported advantages. Roughly 77% of participants who completed the study were planning to continue using the patch. The 35.5% rate of complete or partial detachment of at least one patch was considerably higher than reported in previous studies of adults. As in adults, the most commonly reported complaints were application site reactions and breast discomfort. CONCLUSIONS: This evaluation found an overall positive impression of the new transdermal contraceptive patch, with good rates of short-term compliance and few side effects among adolescents. However, the high degree of detachment unique to this sample of adolescents is concerning and requires further evaluation.  相似文献   
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PURPOSE: The clinical objective of this trial was to evaluate gefitinib in patients with metastatic colorectal cancer that had progressed despite prior treatment. Serial tumor biopsies were performed when possible and analyzed for activation of the epidermal growth factor receptor (EGFR) signaling pathway. Serial serum samples were measured for amphiregulin and transforming growth factor-alpha (TGFalpha). PATIENTS AND METHODS: One hundred fifteen patients were randomly assigned to receive gefitinib 250 or 500 mg orally once a day. One hundred ten patients were assessable for clinical efficacy. Biologic evaluation was performed on paired tumor samples from 28 patients and correlated with clinical outcome. RESULTS: Median progression-free survival was 1.9 months (95% CI, 1.8 to 2.1 months) and 4-month progression-free survival rate was 13% +/- 5%. One patient achieved a radiographic partial response (RR = 1%; 95% CI, 0.01% to 5%). Median survival was 6.3 months (95% CI, 5.1 to 8.2 months). The most common adverse events were skin rash, diarrhea, and fatigue. In the biopsy cohort, expression of total or activated EGFR, activated Akt, activated MAP-kinase, or Ki67 did not decrease following 1 week of gefitinib. However, a trend toward decreased post-treatment levels of activated Akt and Ki67 was observed in patients with a PFS higher than the median, although these did not reach the .05 level of significance. CONCLUSION: Gefitinib is inactive as a single agent in patients with previously treated colorectal cancer. In tumor samples, gefitinib did not inhibit activation of its proximal target, EGFR. Trends were observed for inhibition of downstream regulators of cellular survival and proliferation in patients achieving longer progression-free survival.  相似文献   
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Lower incidence and mortality rates from prostate cancer(PCa)have been shown in Asian men in general compared to Westerners.This is the first study detailing th...  相似文献   
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