1. The main issue of The Lancet is the top medical journal in the world, and the sub-issue of The Lancet is the sub-issue of the main issue of The Lancet.

2. The main journals of The Lancet cover many fields and publish many important academic papers, which play an important role in the global health cause. Focus on medical research in a specific field. For example, The Lancet Oncology is the world's leading journal of clinical oncology, and The Lancet Child and Adolescent Health and other sub-magazines cover medical research in different fields.