以前为了确定标准X射线胸透检查是否可以降低肺癌的死亡率的研究没有取得成功，主要是因为包含的参与人数太少了。
Previous studies to determine whether standard chest X-ray examinations can reduce lung cancer mortality have not been successful, primarily because of the small Numbers of participants enrolled.
治理指标表明，当治理出现一个标准偏差的改善，从长期看收入就会提高三倍，婴儿死亡率降低三分之二。
The indicators show that when governance is improved by one standard deviation, incomes rise about three-fold in the long run, and infant mortality declines by two-thirds.
世卫组织正在努力减少孕产妇死亡率，采取的手段是提供基于证据的临床和规划指导，制定全球标准，以及为会员国提供技术支持。
WHO is working to reduce maternal mortality by providing evidence-based clinical and programmatic guidance, setting global standards, and providing technical support to Member States.
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