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The rule, or measuring rod, which the behaviorist puts in front of him always is: Can I describe this bit of behavior I see in terms of "stimulus and response"?
丙型肝炎的挑战不仅在于找到病毒,还在于理解它是如何逃避免疫系统的。
Make it simple. Make it memorable. Make it inviting to look at. Make it fun to read.