On an engine test bed, two selected exhaust purifiers with DOC type experienced comparison emission tests; the results validated the sizable effects of the outer purifier means.

在发动机试验台架上，选择了两种DOC型尾气净化器，进行了排放比对试验，验证了机外净化的效果。

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Another doc on the Lilly payroll was cited for doing unnecessary nerve tests on patients.

FORBES: Is Your Doctor On Big Pharma's Payroll?