a shot in the arm

基本解釋

Richardson describes traveling alone as like “a shot in the arm”, which “unleashed a better more confident person that was ready to tackle anything”.
理查德森把獨(dú)自旅行看作是“一劑強(qiáng)心針”，它“使你得到釋放，成為一個更加自信的人，從而準(zhǔn)備好應(yīng)對任何情況。”
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.
如果能證實(shí)超對稱性的確存在，那無異于為M理論注入了一針強(qiáng)心劑，物理學(xué)家們可以借此來解釋宇宙誕生之初，各種作用力是如何從一種超級作用力里誕生的
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.
如果能證實(shí)超對稱性的確存在，那無異于為M理論注入了一針強(qiáng)心劑，物理學(xué)家們可以借此來解釋宇宙誕生之初，各種作用力是如何從一種超級作用力里誕生的

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.
FORBES: China Outlook Improving; Time For A Rebound?

something that has a sudden and positive effect on something, providing encouragement and new activity