Madison Police say they arrested a 23-year-old man as he came out of an apartment early Thursday morning with a knife in his hand.  When officers responded to a call at about 2:20 A-M they found a bloody woman outside of that apartment, apparently trying to hold the door shut.  Tomas Campos-Aguilar came out carrying the knife, but he immediately dropped it when he saw the officers — and he was taken into custody.  A neighbor had called 9-1-1 after hearing yelling and screaming.  Campos-Aguilar faces tentative charges of domestic strangulation, disorderly conduct, battery, false imprisonment and criminal damage to property.