What is the earliest and quickest response of blood vessels after an injury? () A: Vascular endothelial cell contraction B: Platelet aggregation C: Clot retraction D: The wound callus E: Blood flowing retarding

What is the earliest and quickest response of blood vessels after an<br/>injury?() A: Vascular endothelial cell contraction B: Platelet aggregation C: Clot retraction D: The wound callus E: Blood flowing retarding

The following statements , _____, illustrate the functions of calcium. A: nerve cells need calcium for nerve impulse conduction B: muscle needs calcium to contract C: blood needs calcium to clot D: bone needs calcium to make itself hard

In patients with thrombocytopenia, spontaneous bleeding spots and<br/>purpura often appear on the skin and mucosa, mainly due to () A: Not easy to form antithrombus<br/>[B].<br/>Blood vessels do not constrict easily B: Failure to maintain the integrity of vascular endothelium C: Blood clot retraction disorder D: Blood clotting disorders

Where do the clots come from? Blood flow slow down. A sudden change in heart rhythm leads the upper chambers to contract abnormally. Platelets, clotting factors, and fibrin stick together. The clot can be carried up towards the arteries and blood vessels supplying the brain until getting to one it can't squeeze through. A: ①②③④ B: ②①③④ C: ②③①④ D: ①③④②

How is the embolism of a thrombotic stroke formed? ① Blood flow slows down. ② A sudden change in heart rhythm prevents the upper chambers of the heart from contracting normally. ③ Platelets, clotting factors, and fibrin stick together. ④ The clot can be carried up towards the arteries and blood vessels supplying the brain until it can’t squeeze through. A: ②④③① B: ②①③④ C: ②①④③ D: ①②④③

产妇，28岁，孕1产0，宫口已开全。阴道检查：胎头矢状缝与骨盆横径一致，小囟门在1点处，大囟门在7点，为何种胎方位（ ） A: ALOA B: BROT C: CLOT D: DROA E: ELOP