Nerve injury, which can be due to diabetes or seat belt injury after a motor vehicle accident, for example, also can cause meralgia paresthetica.

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"If you are going to try and make fatigue sleepiness a criminal legal issue in a motor vehicle accident, you have a lot, lot more to prove, " said Patrick Bruno, who defended Williams in the bus crash case.

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Here is the setup of these studies: Take people who have just had something very bad happen to them, like a motor vehicle accident or a rape, and within a few hours or a day or two at most, flip a coin and put half these people on a beta blocker and half on an inactive substance that looks the same (i.e. placebo).

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According to the Insurance Institute for Highway Safety, 35 percent of all deaths among 16-19 year-olds are motor-vehicle related, with the risk of getting into an accident among teenage drivers being particularly high during the first months after obtaining their licenses.

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