Study of Beraprost sodium Tables combination with Aspirin for prevention of type 2 diabetes patients’ atherosclerosis progress

INTERVENTION: A:Beraprost sodium Tables combination with Aspirin ;B:Aspirin; CONDITION: Arteriosclerosis PRIMARY OUTCOME: The change rate of IMT; SECONDARY OUTCOME: ABI, PWV, SOD, Nitro tyrosine;VCAM‐1, TNF‐alpha;vascular event; INCLUSION CRITERIA: 1. T2DM patients between the age of 50 and 75; 2. At least one site IMT>=1.1mm; 3. AST, ALT, SCr<=1.5 times normal value; 4. No ischemic vascular events in 3 months, include myocardial infarction, unstable angina pectoris, stable stenocardia, cerebral arterial thrombosis and hemorrhagic apoplexy; 5. SBP<160 mmHg, DBP<100 mmHg; HbA1c<8.0%; 6. No anti‐thrombus drug and antiplatelet drug in last 3 months; 7. Informed consent.