Of 13 population clusters, seven were randomly allocated to three rounds of screening between 1996 and 2004, while standard care was provided in six (control arm).

在13个人口群中，7个被随机分配到1996年至2004年的3轮筛查，而另外6个（对照组）获得的是标准护理。

youdao

A city of northern Maryland on an arm of Chesapeake Bay northeast of Washington, D. C. it has been a busy port since the 18th century. Population, 736,014.

美国马里兰州北部一城市，位于华盛顿特区东北面的切萨皮克湾的一个分支处。自18世纪以来不断是忙碌的口岸。生齿736,014。

youdao

A city of northern Maryland on an arm of Chesapeake Bay northeast of Washington, D. C. it has been a busy port since the18th century. Population, 736, 014.

巴尔的摩马里兰州北部一城市，位于华盛顿特区东北面的切萨皮克湾的一个分支处。自18世纪以来一直是繁忙的港口。人口736,014。

youdao

In a unique economic experiment, 16 countries with a combined population of 329m have handed over monetary sovereignty to an entity at arm's length from national politics: the European Central Bank (ECB).

ECONOMIST: Holding together