First quarter profits at the US owner of Miller Brewing, Philip Morris Cos, were up almost 6% percent, as its tobacco business performed strongly and Miller beer showed improvements.   Earnings were at US$2.47 billion, or US$1.14 per share on an underlying basis, up from US$2.34 billion, or $1.05 cents, in the same periods last year. The figures were at the top end of analysts' expectations.