[Retracted] Changes of Serum D-Dimer, NT-proBNP, and Troponin I Levels in Patients with Acute Aortic Dissection and the Clinical Significance

Table 2

Comparison of symptoms and signs.

	n	Chest pain	Back pain	Abdominal pain	Syncope	Shock	No arteries in the upper extremities	Asymmetry of upper extremity blood pressure
Observation group	40	38	25	7	8	8	2	2
Control group	40	35	19	5	6	5	0	0
χ ^2		1.409	1.818	0.392	0.346	0.827	2.051	2.051
		0.235	0.178	0.531	0.556	0.363	0.152	0.152