Table 2. Measurement of collagen fibrils, interfibrillar spacing, and proteoglycans mean area of tree shrew and human cornea fixed in cuprolinic blue in 2.5% glutarldehyde and embedded in spur resin.

Animals	Diameter minimum (nm)	Interfibrillar spacing (nm)	Proteoglycan mean area (nm2)
Tree shrew cornea	39.00±4.25	52.91±6.07	390±438*
Human cornea	38.65±4.37	52.52±5.36	93±74

*Statistically significant difference with p<0.05.