1 ) , the stenosis was classified according to the Stanford classification [ 7 ] system into 4 types : ( i ) type I describes a partial obstruction of the SVC ( up to 90 % ) with remaining patency and antegrade perfusion of the azygos vein ; ( ii ) type II shows increasing obstruction ( 90-100 % ) ; ( iii ) type III is complete obstruction with ...
The tulip tree is a deciduous tree with a moderate to rapid growth rate. It has a tendency to produce a strong central leader that forms a tall, straight trunk. When young, this tree tends to have a canopy with an upright pyramidal growth habit, As it ages, the tree becomes columnar or more spreading and open.
In 1947 the tulip poplar was designated as the official state tree of Tennessee. The General Assembly act stated that it was chosen because it grows from one end of the state to the other and was extensively used by the pioneers of the state to construct houses, barns, and other necessary farm buildings..