原文：路透社纽约4月25日电《上夜班降低患帕金森病风险》
译文：《参考消息》2006年04月27日第7版
Working nights may lower Parkinson's disease risk
Tue Apr 25, 2006 1:43pm ET
NEW YORK (Reuters Health) - People who work rotating night shifts appear to have a lower risk of Parkinson's disease, the results of a study published in the American Journal of Epidemiology indicate. （1）Conversely, an increased risk of developing this condition is linked to a longer average duration of sleep.
"Working rotating night shifts disrupts circadian rhythms and may have a wide range of physiologic and psychological effects on shift workers," Dr. Honglei Chen, of the National Institutes of Health, Research Triangle Park, North Carolina, and colleagues write.
"In previous studies, shift work has been linked to higher risks of some chronic diseases, including cardiovascular disease and certain types of cancers," they note, （2）but any effect on the risk of developing Parkinson's disease has not been investigated.
The researchers therefore evaluated data from the U.S. Nurses' Health Study, which enrolled 84,794 female nurses, to see if there was an association between working rotating night shifts and Parkinson's disease risk. The risk of Parkinson's disease was 50-percent lower among women who had at least 15 years of night shift work compared with those who never worked rotating night shifts.
After accounting for differences in age and smoking status, the investigators found that a longer sleep duration was associated with a higher risk of Parkinson's disease. Compared with nurses who slept no more than 6 hours per day, those who slept 9 or more hours per day had a 84-percent increased risk.
（3）Plausible biologic explanations for these results are lacking, Chen's team points out. They note that shift work has been associated with modest increases in blood levels of estradiol and uric acid, "both of which may be protective against Parkinson's disease."
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2006年04月27日参考消息7版《上夜班降低患帕金森病风险》全文如下：
【路透社纽约4月25日电】《美国流行病学杂志》公布的最新研究结果表明，常上夜班的人患帕金森病的风险似乎较小。（1）相反，睡眠时间较长的人患这种病的可能性较大。
位于北卡罗来纳州“研究三角区”的国家卫生研究院的陈博士及其同事在研究报告中写道：“隔三岔五值夜班会打乱昼夜节律，这可能会对上夜班的人产生各种生理和心理影响。”
他们指出：“以前的研究表明，经常倒班的人患心血管疾病和癌症等慢性疾病的风险较大。”（2）但到底上夜班与患帕金森病的风险有什么关系，此前一直没有这方面的研究结果。
为了搞清楚上夜班与患帕金森病风险之间的关系，陈博士等研究人员对美国“护士健康研究”计划的资料和数据进行了仔细分析。“护士健康研究”计划对8万多名女护士进行了跟踪调查。至少在15年里交替上夜班的女性比从来不上夜班的女性罹患帕金森病的风险低50%。
研究人员发现，除去年龄和吸烟等因素，睡眠时间越长的人患帕金森病的风险越大。同每天睡眠不足6个小时的护士相比，每天睡眠超过9个小时的护士患这种病的风险高出84%。
陈博士的研究小组说，（3）现在还无法从生物学角度对这种研究结果作出解释。他们还说，上夜班会导致血液循环中雌二醇水平和尿酸含量增加，而“它们或许可以帮
