It depends on how thick or thin the slices are, whether it is light meat from the breast, or dark meat from the leg, and whether the skin was removed or not before eating. Here is a variety of samples.
Cut from a home cooked (not deli) roast turkey there are:
approx 62 calories in a 1 oz, or 28g, slice of turkey dark meat including the skin
approx 52 calories in a 1 oz, or 28g, slice of turkey dark meat with the skin removed before eating
approx 38 calories in a 1 oz, or 28g, slice of turkey breast with the skin removed before eating
approx 53 calories in a 1 oz, or 28g, slice of turkey breast including the skin.