Artificial lens

The polysulfones are biologically inert and resistant to steam sterilization and y-radiation what avails people to use them in medicine when implanting artificial lens instead of removed due to a surgical intervention and when producing medical tools and devices (inhalers bodies, ophthalmoscopes, etc.). 

Food materials, cosmetics, culture substrates Artificial lens, optical lenses, display materials Cell cultures, artificial skins, contact lenses Artificial muscles, actuators, switch elements, shape memory materials Sensors, electrodes... 

Sail, K. N., Cohen, S. M., Christensen, M.T., and Stein, J. M. (2006), An evaluation of the efficacy of a cyclosporine-based dry eye therapy when used with marketed artificial tears as supportive therapy in dry eye, Eye Contact Lens Sci. Clin. Pract., 32, 21-26. 

Dry eye symptoms and significant ocular surface disease frequently occur in patients taking isotretinoin.The associated symptoms may be accompanied by blepharocon-jimctivitis. The presence of isotretinoin in tear fluid decreases stability (and tear break-up time) of the lipid layer of the tear film but may also cause a decrease in aqueous production, leading to ocular surface dryness. These effects could be responsible for the dry eye symptoms, contact lens intolerance, superficial punctate keratitis, and conjunctival irritation accompanying isotretinoin therapy. Use of artificial tear preparations may help to alleviate the associated discomfort. 

Figure 26.31 depicts the same measuring procedure applied to a contact lens material sheet (A) untreated, (B) (CH4 + air) plasma treated, and (C) (CH4 + air) plasma treated and then O2 plasma treated. Characterizing aqueous film stability on untreated and plasma-modified contact lens materials using artificial tear fluid by... 

Dyed shell may have an artificially bright colour. Viewed with a lOx lens the dye can be seen to accumulate in patches. This is especially noticeable in the areas of organic matrix on the surface of dyed abalone or paua shell (Fig. 10.15). 

Methylcellulose is a vehicle used in eye-drops and contact lens solutions (SEDA-1, 369). It is non-irritant and has a good refractive index. A 1% solution is well retained in the conjunctival sac. Corneal cultures have been stimulated by methylcellulose, resulting in increased growth of cells (2) tear-film break-up time was increased four-fold with 2% methylcellulose. Hydroxypropyl methylcellulose is also used as artificial tears for people with dry eyes (3). 

Most of the damage to the eye caused by direct irradiation from the sun or artificial sources is from ultraviolet radiation. However, in the presence of a light-activated (photosensitized) diagnostic dye or drug, patients are in danger of enhanced ocular injury from ultraviolet and visible light. The extent to which a particular photosensitizer will affect the human cornea, lens, and/or retina in vivo depends upon ... 

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