The femtosecond laser has a number of advantages,.such as short pulse time,.high instantaneous power,.high repetition rate, low monopulse energy, and small ther
Purpose:.Cholesterol granuloma is usually associated with chronic middle ear disease..Involvement of the ethmoid sinus by cholesterol granuloma is rare..We desc
The principle, imaging condition and experimental method for obtaining high resolution composition contrast in secondary electron image were described. A new te