Effect of berberine on expression of transforming growth factor-β1 and type Ⅳ collagen proteins in mesangial cells of diabetic rats with nephropathy Effect of compound Rhizoma Coptidis capsule on expression of transforming growth factor-β1 and type Ⅳ collagen proteins in renal tissue of diabetic rats with nephropathy Effects of Fuzheng Huayu recipe on MMP-2 activity and type Ⅳ collagen expression at fibrotic lung