15713
Introduction : Sigma receptors are involved in several central nervous system ( CNS ) disorders , including mood disorders ( depression and anxiety ) , psychosis , schizophrenia , movement disorders ( i . e . , Parkinson ' s disease ) and memory deficits ( i . e . , Alzheimer ' s disease ) .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
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