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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Heparin inhibits Xa by
assistant
The correct answer is  Heparin contains pentasaccharide unit that activates Antithrombin III & inhibits factor Xa (Thus it is a indirect thrombin inhibitor).
Unfractionised heparin also contains a heteropolysaccharide unit that inhibits factor II a.
LMWH lacks this heteropolysacchoride unit and therefore inhibitors factor Xa only.