However, with long term use of caffeine, your brain responds by creating more adenosine receptors, which means more caffeine is required to elicit the same response.

然而，长期摄入咖啡因，大脑就会制造更多腺苷受体来回应，如果要达到同样的效果，你就需要更多的咖啡因。

It says any possible harm from long term use is likely to be very small and it concludes fears that e-cigarettes are a gateway to smoking are unfounded.’

长期吸食电子烟的危害非常小，而且没有发现电子烟会导致人们吸烟更加频繁的证据。

Medications like phenytoin, an anticonvulsant, uses liver and kidney hydroxylase enzymes for its own metabolism, so especially with long term use, there's not enough vitamin D being generated.

苯妥英，一种抗惊厥药物，会占用肝肾的羟化酶用于药物代谢，所以对于尤其是长期用该药的患者，其维生素D生成可能不足。

The family's pharmaceutical firm is facing civil lawsuits in the United States over claims that Purdue Pharma pushed doctors to prescribe the drug and misrepresented the risks of addiction associated with its long term use.

萨克勒家族的药厂面临着美国的民事指控。普度制药公司被指控迫使医生开该药的药方，并且没有如实说明长期服用该药的副作用。