This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
[{'content': 'The following statements regarding streptokinase are true, except: \nSelect and explain. \nA. It is a protein produced by streptococci., B. Its complex with plasminogen is inhibited by aIpha2-anti plasmin., C. It may rarely produce anaphylaxis, D. It is initially given as a loading dose.', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Streptokinase is a 47-kDa protein produced by beta-hemolytic streptococci. It forms a stable complex with plasminogen, which is not inhibited by antiplasmih. A large loading dose is given intravenously to overcome antibodies that may be formed from prior streptococcal infections. Being a foreign protein it may rarely cause anaphylaxis.', 'role': 'assistant'}]