There could also be "old" and "new" versions of one or more core systems in place to serve these different applications, along with different mid-tier services.

一或多个核心系统的“新”“旧”版本可能同时存在以服务于不同的应用程序，以及不同的中间层服务。

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While the EDS acquisition cemented HP's spot in the top tier of information technology services firms, trailing only IBM, analysts had anticipated big cuts as HP integrated EDS' offerings with its own services arm.

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Where services are collectively consumed, we will transfer power over those services to the lowest practical tier of government, opening up provision to social enterprises, private companies and community organisations.

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Third, and most important, patients may be harmed when services are prioritised economically in single-tier health-care systems like Canada's.

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