An HIV test reveals infection status by detecting the presence or absence of antibodies to HIV in the blood.
艾滋病毒检测通过检查血液中是否存在艾滋病毒抗体，显示感染状况。
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By contrast, in the absence of such a structure, each it initiative might naturally come to its own conclusion as to what Customer Tax Status means and how it should be defined.
It is the responsibility of our Ajax code to check for 304 status, and if found, simply not to change client application state based on the (absence of) data sent from the poll.