The extent of a focal tendon abnormality was intrasubstance in none (0%) of 16 patients with full-thickness tears, one (20%) of five patients with bursal surface partial-thickness tears, two (20%) of 10 patients with articular surface partial-thickness tears, and two (15%) of 13 patients with tendons without tear.
1 Adequate Intake (AI), where no RDA has been established, but the amount established is somewhat less firmly believed to be adequate for everyone in the demographic group.  Tolerable upper intake levels (UL), to caution against excessive intake of nutrients (like vitamin A) that can be harmful in large amounts.
A risk assessment model for establishing upper intake levels for nutrients (1998b) and in the relevant nutrient chapters of the DRI publications. The uses of the various NRVs are summarised in the table below that was adapted from the FNB:IOM (2000b) publication, Dietary Reference Intakes.