7584
Relative to plasma - derived fibrinogen ( pdFI ) , rFI predominately contained a simplified , neutral carbohydrate structure and > 4 - fold higher levels of the gamma ' - chain transcriptional variant that has been reported to bind thrombin and Factor XIII .
 carbohydrate
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 carbohydrate