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What is In psoriasis, the following are seen except: and explain in detail?
Psoriasis is characterized by red, scaly, sharply demarcated indurated plaques present paicularly over extensor surfaces and scalp. Nail involvement is seen with all types of psoriasis and is frequently present with psoriatic ahropathy. An inflammatory ahritis is associated with psoriasis of skin and/or nails with a negative serological test. CNS involvement is not seen with psoriasis.