In a bowl, combine the eggs, sugar, oil and vanilla; mix well. Combine flour, baking powder, cinnamon, baking soda and salt; stir into the egg mixture just until moistened. Toss pears with lemon juice. Stir pears and walnuts into batter (batter will be thick). , Spoon into 2 greased 9x5-in. loaf pans. Bake at 350° for 55-60 minutes or until a toothpick inserted in the center comes out clean. Cool for 10 minutes before removing from pans to wire racks.