1. age<18 years, 2. In the processing of treatment of tumor, 3. in the period of pregnant or lactation, 4. known allergy to low molecular weight heparin, 5. involved in other clinical trial, 6.refuse to signed the informed consent.

1. age<18 years, 2. In the processing of treatment of tumor, 3. in the period of pregnant or lactation, 4. known allergy to low molecular weight heparin, 5. involved in other clinical trial, 6.refuse to signed the informed consent.