Hair coloring by lay people may not be sufficiently accurate. Hair that has been damaged by excessive exposure to chemicals is considered "over-processed". This results in dry, rough and fragile hair. In extreme cases, the hair can be so damaged that it breaks off entirely. The main cases of hair breakage are: Lack of moisture and oils, poor diet, stress, over processing or illness. Skin and fingernails are made of a similar type of keratinized protein as hair. That means that drips, slips and extra hair tint around the hairline can result in patches of discolored skin. This is more common with
Protein–protein interaction Known and Predicted Protein–Protein Interactions (STRING-db), and Unified Human Interactive (UniHI). The aforementioned computational methods all depend on source databases whose data can be extrapolated to predict novel protein-protein interactions". Coverage" differs greatly between databases. In general, primary databases have the fewest total protein interactions recorded as they do not integrate data from multiple other databases, while prediction databases have the most because they include other forms of evidence in addition to experimental. For example, the primary database IntAct has 572,063 interactions, the meta-database APID has 678,000 interactions, and the predictive database STRING has 25,914,693 interactions. However, it is important