[Retracted] Efficacy of Xiyanping in the Treatment of Elderly Patients with Chronic Obstructive Pulmonary Disease and Its Effect on the Expression of GDF-15 and HIF-1α in Serum

Table 2

Comparison of expectoration between the two groups.

Group		Expectoration () (mL)
		Before therapy	Treatment 3 d	Treatment 7 d
Control group	43
Observation group	43
		0.443	10.297	19.342
		0.659	<0.001	<0.001

Compared with before treatment, .