a shot in the arm

基本解释

Richardson describes traveling alone as like “a shot in the arm”, which “unleashed a better more confident person that was ready to tackle anything”.
理查德森把独自旅行看作是“一剂强心针”，它“使你得到释放，成为一个更加自信的人，从而准备好应对任何情况。”
Confirmation of supersymmetry would be a shot in the arm for M-theory and help physicists explain how each force at work in the universe arose from one super-force at the dawn of time.
如果能证实超对称性的确存在，那无异于为M理论注入了一针强心剂，物理学家们可以借此来解释宇宙诞生之初，各种作用力是如何从一种超级作用力里诞生的
Confirmation of supersymmetry would be a shot in the arm for M-theory and help physicists explain how each forces at work in the universe arose from one super-force at the dawn of time.
如果能证实超对称性的确存在，那无异于为M理论注入了一针强心剂，物理学家们可以借此来解释宇宙诞生之初，各种作用力是如何从一种超级作用力里诞生的

The rollout of LTE or 4G will be a shot in the arm for most wireless vendors.
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Given the difficulties and delays involved in developing new drugs, microdosing could offer the industry a shot in the arm.
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Consumption has seen a secular improvement, but it is more of a stabilizing force rather than a shot in the arm.
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something that has a sudden and positive effect on something, providing encouragement and new activity