IBM Corp shares, which have been making new lows all over the place in the past couple of weeks, reversed the trend yesterday in style, and were up $1.125 at $83.375 at noon yesterday at a time when the market was following Tokyo’s plunge with the Dow Jones Industrial Index off another 48.3 points at 3,165, after Merrill Lynch analyst Daniel Mandresh raised his opinion of the shares to 2-1, or above average, intermediate term and buy, long term from 3-1, or neutral, intermediate term and buy, long term; Mandresh, who is noted for calling changes in sentiment about individual stocks regardless of the underlying fundamentals, didn’t change his expectation of $7 a share in profits this year; $1 in the first quarter; in the first quarter of 1991, IBM did 93 cents.