《黄帝内经·素问·病能论》
左脉主要的病症在肾脏，次要的病症在肺脏，所以当有腰痛的症状。
在左当主病在肾，颇关在肺，当腰痛也。
The main cause of the left pulse lies in the kidneys, while the secondary cause lies in the lungs. Hence, there should be symptoms of pain in the lumbar region.
<s>[INST] Kindly elucidate the central themes in this passage in English: 在左当主病在肾，颇关在肺，当腰痛也。 [/INST] The main cause of the left pulse lies in the kidneys, while the secondary cause lies in the lungs. Hence, there should be symptoms of pain in the lumbar region.</s>
Kindly elucidate the central themes in this passage in English: 在左当主病在肾，颇关在肺，当腰痛也。
user
The main cause of the left pulse lies in the kidneys, while the secondary cause lies in the lungs. Hence, there should be symptoms of pain in the lumbar region.
assistant