Leading stocks rose to new highs, but some pared their gains after reports of heightened Russia-Ukraine tensions sent the broad market reeling. Akorn (AKRX) vaulted as much as 9% early in the session before giving up nearly all its gains to close 0.60 higher at 34.93. The stock is 39% above a 25.19 cup-with-handle buy point initially cleared in late April.