Preheat a grill for low heat. Combine the lemon juice and olive oil on a plate. Place asparagus on the plate, and roll around to coat.
Grill asparagus for about 5 minutes, turning at least once, and brushing with the olive oil mixture. Remove from the grill, and place back onto the plate with the oil.
In a large bowl, combine the spinach, Parmesan cheese, and slivered almonds. Cut asparagus into bite-size pieces, and add to the salad along with the lemon juice and oil from the plate. Toss to blend, then serve.
